Dlcockrum Yes I agree that damping may be required in some cases, and that running the paddle at the surface would be best. That is how I set the paddle with the Townsend TT. However, the application of damping should be a last resort. In my experience many folk have applied damping to cure a "resonance" that has resulted from poor set up eg VTA, tracking force, etc and could have been removed by careful set up and in the case of the ET tuning.. I have used electromagnetic damping on my ET2 as discussed earlier in this thread. The damping is created by eddy currents which are only generated when the arm moves relative to the magnet. I have run the ET2 for 25 years and found that the higher compliance cartirdges such as my Shure V15vmr benefitted most from electromagnetic damping. With lower compliance cartridges such as Madrigal Carnegie, Koetsu, Denon 103 and Benz Micro fluid damping slugs the sound in my experience. Bear in mind that I run a decoupled counterweight assembly rather than a sprung counterweight - this has the advantage of keeping the ET2 horizontal mass as low as possible. As your friend Frogman has found, running the counterweight decoupled has produced quicker, more transparent bottom end in his system.The set up procedure he described above is the same as I have used. A little history here - If you read Bruces manual and patents he starts with a low mass arm, and then brings the effective horizontal mass up very gently by providing variable spring rates on the decoupled counterweight. This is formulated to keep the differential resonances between horizontal and vertical in sync with the compliance of the cartridge and the Q of the system. The Q is related to the dampening of the oscillation - the use of magnetic dampening will shift this slightly. Very small adjustments can give quite dramatic changes to the sound, especially in speed, transparency and articulation. Krebs approach has been to load up his ET2 with 30+ grams of lead. He has also removed the decoupling spring from the I beam. Effectively he has added some 60g to the horizontal mass of the ET2. It is no wonder that he has changed his mind after 20 years and is now using fluid damping. Mass increases inertia and has no dampening properties. The high horizontal mass he is running has increased the side forces on the cantilever by over 300% when the arm moves back and forth increasing cantilever flex and distortion. Quote from Thigpen If the weight is coupled the system resonant frequency would be extremely low, a resonant frequency at 3Hz with a significant rise in response (6-12dB) results, which would affect tracking slightly because of the asymmetric position of the cantilever, we opt for splitting the horizontal resonance frequency into two points and lowering the "Q" which improves tracking.
More important than tracking, the intent was to reduce the modulation effects of low frequency energy (FM and AM) that increase distortion in the cartridge I note that DGarretson has been experimenting with his Terminator tonearm. The Terminator in standard form has a much higher horizontal effective mass than the ET. DGarretson has reduced the horizontal mass quite substantially by reproducing some of the parts and yielded significant improvements. |
12-01-13: Richardkrebs
H F Dover.
Still....relative to the groove.
Everyone else understood what I meant. Thank you for that feedback. I'm surprised the results from the Eksen Research survey were available so soon. |
Slaw - As I was curious I sent an email to Jun-Air on weekend when I saw your post. Their help desk was open this morning. I received a response. fyi. Just great customer service btw. Re: A Jun-Air 16-25 w the moisture trap/container option. When the compressor reaches it's max setting, it cuts off and immediately starts expelling air. Can you offer any advice in how to troubleshoot this problem. > > Hi It sounds like a unloader valve is sticking. Thanks, Garry Garry Unrath Technical Assistance/sales Ph. 269-926-6171 ext 1114 > > Thanks Gary How would you recommend fixing this ? Replacing a part or maybe opening it up - can the valve be lubricated in some way? Chris > > Hi Chris First I would try cleaning out with electrical contact cleaner. If that does not help I would suggest a new one, part number 6973080. Thanks, Garry Do you mean to tell us all, they have Home Depots in Canada??? yeah - you know the damn stores are everywhere - at least 70-100 in Ontario There are 10 within an hours of drive of me incl. one 7 mins away by car (or 45 mins away by horse & buggy) Regarding the Timeter pump - can't recall which model you have. Mine is the Aridyne 3000. There is no brass lip to wear. It has a hours counter on it that when reached - hospitals are required to replace them. They are cheap on ebay and the quality of air is the best I have ever experienced. Its a 50 psi pump that I steal 19 psi from and the rest going into the atmosphere. Because of this and with some of the funny posts hear lately, I am thinking of hooking up an extra line for myself this winter - you know - for when the posts crack me up to the point of having trouble breathing. Its around 60-65 db exposed and not closed in so it needs a separate room. |
“If the goal were to keep the cartridge still, then one would never reach the end of the record.
The record groove is not a straight line; it is a spiral with a decreasing radius that requires the cartridge to move to the center of the record as it plays.”
Mumbo Jumbo from Dover.
When you ran these same arguments months ago I suggested you drive quickly over speed bumps and see whether you need damping.
Better still: disconnect one end of the rear dampers of your car (not difficult to do) and drive quickly over speed bumps. Tell us whether you need dampers. Remember to fasten your seat belt! |
Something I have never seen before and here at audiogon. NIB Stock ET2 New in the box according to the ad. Not affiliated with the ad. hey - it even comes with a damping trough! I find the nice thing about this damping trough is that it gives you another option. (Be nice if my wife and kids came with options) I have found some records sound great no matter how you play them. Others contain great music but the way the record was made .... leaves something to be desired. All it takes is a quick turn of the paddle screw to engage and disengage it. the thing I don't like about the trough is it can be messy. If away for a few days I like to cover my table. you need to be careful with the fluid, even though there is only 1 cc of oil in it. |
12-04-13: John47
I suggested you drive quickly over speed bumps and see whether you need damping Your analogy does not apply. The goals are quite different. If a record has a warp, for example, the goal is to measure the groove modulations, not the size of the warp in the record. If the cartridge is impeded from moving up and down with the warp, then the measurement of the groove modulation will be grossly inaccurate. This also applies with lateral motion. Loading the tonearm with mass, as Richardkrebs has advocated, increases inertia, and as the groove moves in and out, the increased resistance to lateral movement means that the cantilever will flex more and the measurement of the groove modulation will be impaired and inaccurate. This is the fundamental principle upon which Bruce designed the LOW mass, decoupled counterweight ET2. Richardkrebs in this thread has advocated converting this tonearm into a very HIGH Mass arm. He also advocates removing the decoupling. These alterations add 60g to the effective mass of his ET2, increasing inertia and resistance to lateral motion by over 300% compared to a standard ET2. These gross alterations will result in destroying the inherent advantages that the LOW mass ET2 offers in superior tracking and minimising distortion. Numorous contributors to this thread have found that setting the arm up as per Bruces recommendations produces superior sound which is clearly audible. |
Dover
"Loading the tonearm with mass, as Richardkrebs has advocated, increases inertia, and as the groove moves in and out, the increased resistance to lateral movement means that the cantilever will flex more and the measurement of the groove modulation will be impaired and inaccurate.
This is the fundamental principle upon which Bruce designed the LOW mass, decoupled counterweight ET2. Richardkrebs in this thread has advocated converting this tonearm into a very HIGH Mass arm. He also advocates removing the decoupling. These alterations add 60g to the effective mass of his ET2, increasing inertia and resistance to lateral motion by over 300% compared to a standard ET2.
These gross alterations will result in destroying the inherent advantages that the LOW mass ET2 offers in
superior tracking and minimising distortion."
This is what you wrote on date xx ..... take your pick.
Repetition is the sincerest form of flattery. |
The HP manifold for my ET-Two 2.0 arm arrived from Bruce yesterday. After a much easier-than-anticipated swap out of the manifolds (simple thumb-push out and in), I cranked up the regulators to deliver 17 psi to the arm and settled in for a listening session that stretched into the wee hours of the morning and much of today.
To say that the HP manifold made a significant sonic improvement would be a colossal understatement. Each and every aspect of reproduction improved by a major step function. No need to specify micro/macro dynamics, impact of attack, clarity of decay, detail retrieval, low-frequency definition, warmth/richness, soundstage imaging/layering, space/air/transparency, or other descriptives. It simply improved them all and by a large margin. Night and day. REALISM!
Keep in mind that I had already recently upgraded the air supply system (Medo compressor, DIY surge tank, dual regulators, etc) and, while these were not revelatory until coupled with the HP manifold, surely all of those upgrades now contribute substantially to the overall result. I would be thrilled even had these upgrades cost 10 times what they actually did.
Many thanks to all of you on this thread, either by documenting these improvements here or by response to me directly, and especially to Frogman for providing advice, information, and the inspiration to achieve this elevated level of performance from my analog rig.
I am eager to rediscover the sound of my LP collection "as if for the first time".
Dave
|
Excellent! Congrats, Dave. Let me know when you are ready and I will send you the wire loom for a straight shot from cart clips to preamp to try. I think you will find that revelatory as well. |
My ET spring a leak, actually one of the o'rings failed. This necessitated disassembly. I took the opportunity to give it a spring clean and weigh it. Total weight excluding cartridge was 86 grams (95 grams with cartridge). I have on loan a standard I beam, counter weight assembly (thank you Grant) this weighs in at 47 grams, excluding the spindle clamp. This would put the total weight of a standard ET2 up to 77 grams with an aluminium wand and 85 grams with a magnesium wand. It is my intention to revisit the use of a sprung counterweight. I first did this test some 16 years ago and preferred a fixed counter weight. Before I made the decision to change, I considered the ramifications of such a move. One parameter which was looked at was tracking of eccentric records. I did not want to damage my cartridge and records with the stylus slewing about in the groove.
With this issue, resonance theory saved the day.
A way back in this thread, I posted a transmissibility graph. I had hoped that this would resolve the discussion. This shows structural movement for various excitation frequencies above and below a given resonance frequency. The resonance frequency of the counterweight assembly ranges from 2 to 5 hz. The excitation frequency from an eccentric record at 33 rpm is 0.55 hz.
If we apply this 0.55 hz input to the sprung counterweight arm, we can see what happens... transmissibility approaches 1. This means that the whole structure moves. The cartridge "sees" the counterweight.
Lets put this clearly. When tracking an eccentric record with a standard ET2, the stylus/cantilever is required to accelerate sideways, 1320 times per LP side, the TOTAL weight of the arm; wand, gooseneck, spindle, cartridge, PLUS I beam and counterweights. Depending upon the counterweights used and the weight of the cartridge, this total can approach 100 grams. The same ball park as my arm.
|
Just wanted to add a couple of thoughts re the HP manifold. In a couple of the previous posts there appeared to be the suggestion that the HP manifold was not necessarily a worthwhile upgrade over the original LP manifold. Dave has corroborated what I have always felt: that the HP version is very worthwhile and a very significant upgrade over the LP version. After living with the LP version for several years before upgrading to the HP, I am confident that Dave's experience mirrors mine. I bring this up since the 2.5 manifold is no longer available, so this is an interesting option for all owners of the ET2 for a very reasonable price. Of course, the pump/compressor has to be a suitable one. |
12-09-13: Richardkrebs
Depending upon the counterweights used and the weight of the cartridge, this total can approach 100 grams. The same ball park as my arm. You have stated in earlier posts that you added 30g of lead to your ET2 plus lead to the headshell and replaced the original plastic counterweight beam with an M10 threaded rod. You have strongly advocated adding more mass to the ET2. It is simply not possible to add 30 plus grams of lead and arrive at the same net weight to an unmolested ET2. With my low compliance Denon 103 weighing 9 gms I could balance the ET2 with 35g at the counterweight giving a total mass of around 79 grams. ( That would be about 43 gms using your maths ). Re your comments on transmissibility - 03-14-13: Richardkrebs
Shown here is a link to the Math on driven harmonic oscillators, a mathematical representation of an arm/ cartridge assembly. It shows in both formula and graphical terms what I have been trying to say. The Math is a bit of a struggle but fortunately the graphs show the results.
en.wikipedia#Driven_harmonic_oscillators I have pointed out before, the model you refer to applies to a harmonic oscillator like a pendulum. You are incorrect if you think that this represents a cartridge. The arm/cartridge/record interface has 2 fulcrum points - The stylus point around which the cantilever pivots, constrained by the groove. The cantilever suspension point, about which the cantilever also pivots, but which is partially constrained by the rubber suspension damping. The forces involved are double ended - you have the groove applying a force to one end of the cantilever via the stylus. The other end of the cantilever has forces being applied from the arm motion. The 2 forces are not in sync because there is a suspension joint between the cantilever and the arm. In order to conceptualise this, think of 2 people holding a pipe and each one trying to move it sideways out of sync with the other. That is what the cantilever experiences. It is not a pendulum and it is not a harmonic oscillator. The Wikipaedia example you have chosen does not apply. Rather than get lost in fanciful mathematics the bottom line is that the cantilever flexes when faced with an eccentric record, even more so with added lead mass. I quote Bruce Thigpen directly the cartridge will "see" .55Hz mounted in any tonearm, more so in one with higher horizontal inertia
I don't think Kuzma means the stylus does not deflect at all at .55Hz, that would defy physics Postulating that the cantilever does not flex with an eccentric record and that adding mass has no impact defies physics. |
I bring this up since the 2.5 manifold is no longer available Hi Frogman I guess the recent interest has cleaned Bruce out of his 2.5's . I know of another ET2 owner with an interest to upgrade so I emailed Bruce for him.
Bruce
re: ET 2.5 availability
is it still possible for someone with a 2.0 to upgrade to a 2.5 with you ?
they send u their 2.0 manifold and spindle and you return a 2.5 spindle and manifold.
Also can the 2.5 still be bought new from you ?
thanks Chris
Chris,
Both are not available right now, it is likely that we will have more in about 4 months, thank you very much.
brucet
So this is a temporary situation. I agree that a low pressure (LP) 2.0 upgraded to a HP is very worthwhile. The cost is about the price of two Canadian gas tank fill ups. Cheers |
Hi Richard " spring cleaning ? " I wish. its freezing here. where to put the Christmas tree for best room acoustics in a shared room ? I am interested in your I Beam testing/findings. Is your manifold a standard low pressure one ? If so consider including tests that use just enough PSI to make the spindle float and work as Bruce designed. I think Dave's recent observations on music presentation when PSI is run higher on a regular LP 2.0, show how much we change change things up with PSI. This will change your findings/results. I am also interested to know what your and others definition is of a really eccentric record ? I believe we are all different in what we will tolerate as far as this is concerned. Wouldn't it be nice if someone came up with a record making machine that could produce holes in vinyl - LIKE A CD. Looking at the way the groove looks. http://embrangleroot.files.wordpress.com/2012/08/tumblr_m7ob01afye1qlixleo1_1280.jpg?w=614Now add an off centered hole to that mess. |
Chris.
Yes spring has sprung here. BBQ's, Boating, Fishing, and company with great friends watching long sunsets over a glass of wine. I suspect that it was the change in temperature that precipitated the o"ring failure.
I am using a HP manifold at around 18 psi.
HF Dover.
I knew that you would bring up the added weight question inside the spindle. The 30 gm adder was a guess based on 16 year old memory. Clearly my guess was well overstated. I will be removing this when I do the swing arm counterweight test to bring the arm as close to stock as possible. The 95 gm total, arm and cart weight, is accurate. This depending upon c/weights and cart used by others, being more or less the same as a standard ET2 using a mag wand.
For further discussion on how every ET2 on the planet requires the cartridge to push sideways the total arm weight when tracing an eccentric record, please read below....
> Bruce.
> I have been thinking about the horizontal effective mass of your ET2 and have a question please.
> The horizontal effective mass calculation you give in the tech section of the manual shows an arm mass of 30 grams which is then added to the weight of the cartridge to give total horizontal mass. This calculation ignores the weight of the counter weight since it is decoupled via the leaf spring.
>
> My question is around the horizontal effective mass seen by the cartridge when tracing an eccentric record. The resonant frequency of the counterweight spring assembly is 2-5 hz and the lateral tracing frequency of an eccentric record at 33 rpm is 0.55 hz.
> At 0.55 hz the transmissibility would be approaching 1, even with a counter weight spring frequency of 2 hz.
>
> This would therefore mean that the cartridge "sees" all of the counterweight weight when tracing an eccentric record?
> Thus the effective mass at this low frequency, 0.55 hz, would be the total weight of the arm and cartridge including the beam and the weights it is carrying.
>
> Many thanks
>
> Richard.
>
>
Richard,
Below the counterweight decoupling frequency cutoff ~ 2hz, the effective mass becomes the total mass. Then you have another resonance freqeuncy to add to the mix which is typically much greater than .55Hz.
So yes, it sees all of the mass below 2Hz, but the combination of those masses results in a cantilever resonance above that frequency. You should see the arm move back and forth with the eccentricity of a record at .55Hz as opposed to deflection of the stylus.
I hope this helps and thank you very much for the interest.
brucet
|
Why do you keep (repeatedly) trying to prove the arm designer wrong? |
Chris,
We are children of the revolution, the swirling 1960´s and we "speak" the same language. We have certain respect to our past, and it´s music itself. The super groups we listened when we were kids will be our musical heritage till the end of time.
The turning point for me personally was in 1974 when I used to listen FM radio and I occasionally managed to record some strange and quite extraordinary music to my PHILIPS radiorecorder (at the time I didn´t have a record player !) I captured "Shine on Brightly" by Procol Harum, "Meddle" by Pink Floyd, "Brain Salad Surgery" by ELP and "Starless and Bible Black" by King Crimson on tape. And "Twin Peaks" by Mountain as well, probably the heaviest/fattest bass sound ever put on vinyl. Thanks to Felix Pappalardi, the great late producer, band leader & musician. Of course, we kids listened the pop music too.
But I hadn´t any idea where this all will lead in next year. My dear dad bought me my first stereo system. The finest part of the sale was a bonus, the double album "666" by APHRODITE´S CHILD, would you believe ! Oh yes, the mighty music composed by Vangelis & sung by Demis Roussos who has a very unique and beautiful voice. This stunning music blew this kid´s mind away and never looked back ever since.
But it still took 26 years to find another musical treasure hidden in time, the fantastic Classic Italian Progressive music. In 1973 Alphataurus the Mighty Dove abandoned manking in frustation & anger because of commersializing the music culture. But mankind still has hope as we saw the triumphant return of Alphataurus in 2011 as documented in "Alphataurus Live in Bloom"
http://www.ebay.co.uk/itm/LIVE-IN-BLOOM-ALPHATAURUS-VINYL-NEW-/370760653864?pt=UK_Records&hash=item56530e9c28
And resulting a Renaissance in Prog Music, especially in Italy after all the years ! Another gem:
http://www.btf.it/dvd/prog-exhibition.html
Another thing I regard you as a sir is your TT, The Platine & ET-2. I think it´s a very special combination. In fact, you are running a double air suspension system turntable truly.
This unique and very sophisticated techique you are using proves that you take audio and music VERY seriously and you truly respect the things you love.
Furthermore and as for an extra suspension, I would suggest you to try a Reso-Mat made by Vic himself. IME over the years it is a true bargain in audio. In my system the improvement in audio guality & quantity is really huge.
It´s due to it´s feature that vinyl sits freely and uncompressed on vinyl spikes that allow resonances vanish into air and not bouncing back to vinyl and rearching stylus. Many things in mechanics are simple, also this. It works !
http://www.ebay.co.uk/itm/RESO-MAT-TURNTABLE-PLATTER-MAT-FOR-TECHNICS-SL1200-GARRARD-401-/181111989567?pt=UK_AudioTVElectronics_HomeAudioHiFi_Turntables&hash=item2a2b1da53f
Btw, thaks us showing the way to the record groove, I actually haven´t seen it so clearly before ! What a revelation !
Cheers |
Harold-not-the barrel.
Absolutely agree with your eloquent post. You did forget to mention Jethro Tull though :-)
Although I have not met Chris, it is clear to us all that he is passionate in the extreme about his music and is a gentleman. |
Harold/Richard - thanks passionate in the extreme about his music imo - everyone here is equally passionate in the extreme about their music. I remember exactly the moment when I realized music was going to be something special. I was only a single digit in age and I heard "I wanna hold your hand" Beatles in 68 or 69 for the first time. right now I am hunkering down for lots of music because its cold outside and only going to get colder. the picture of that groove reminds me of bare cold and makes me think of Springsteen's song titled "Badlands" Poor man wanna be rich
Rich man wanna be king
And a king ain't satisfied
'Til he rules everything
Springsteen - Badlands So some are rich and even fewer are kings. Some folks are so passionate in the extreme about their music and have the resources to create concerts in their home for others to enjoy. If you scroll down you will see how the concert is taped and then those interested can go listen to the reproduced sound to compare. Harold - I don't know what it is about Italian music. I can't understand a word of it but I can listen to it for hours. Cheers Chris |
Richard, Unfortunately I don´t recall FM radio played a JT album in its entirety in this remote area LOL. But I do recall vividly as "Songs from the Wood" album was the only subject in one music lesson in high school in 1977. I felt huge respect for the teacher due to his knowledge/respect he had and he really played most of the album. |
Ct0517: Thanks for your going the extra mile on my compressor issue. This avenue would have been my next one. I have of late, been focused solely on very pointed issues and didn't take the time to inquire with the obvious source.
On another front. Regarding the end users preferred listening air pressure. I know you and a few others are set on 19 psi. I have varied but keep coming back to 18.5 psi. I find over & over again that I lose valued bass definition and weight. With my latest upgrade,a pair of Martin Logan Depth i, this is even more clearly defined. What is it you or others prefer going to 19 psi? There certainly could be the difference in system synergy/integration within one's room and end user's preference. |
Harold
My music awakening happened when our school music teacher played us side one of Aqualung. She refused to play side two because it criticized the Church of England and had a bad word "balls"
I remember being stunned upon first hearing this record.
I persuaded her to let me record the album, so I took my Sony radio cassette player and placed it in front of the single mono speaker of the school record player.
Typing this takes me right back in time to the feeling of excitement and thrill of hearing this music and being able to play it whenever I wanted.
The emotional power of music. |
12-13-13: Richardkrebs
I persuaded her to let me record the album, so I took my Sony radio cassette player and placed it in front of the single mono speaker of the school record player. So nothings changed then ! |
Speaking for myself and the pressure gauge that I use, I doubt very much that it is accurate to within .5 lbs. So, it is entirely possible (and probable) that my arm is seeing anywhere between 18.5 and 20 lbs. I say that based on the less-than-sota quality of the gauge and the fact that the check-valve in my surge tank (20 lbs max rating), on any given day, will inexplicably open or be audibly on the verge of doing so with the dial on the gauge set to 19, and will be fine on another day. I don't know if its possible for voltage fluctuations to affect the pumps output or perhaps humidity levels? Having said all that, I would say that the somewhat broad range of 17-20 lbs is what gives me the best sound IN MY SYSTEM and TO MY EARS. I am impressed that you can reliably hear a difference of .5 lbs. |
Slaw What is it you or others prefer going to 19 psi? My ET 2.5 was a custom build by Bruce designed for 19 psi. It will still work at 18 but below that it starts having problems. With no air on the spindle it is very tight in the manifold. I am using it as designed by Bruce. Now for why I had Bruce set it up for 19 psi this is another story and it is documented on the first couple pages here. It involved putting my portable regulator in my lap and raising/lowering the pressure with it while my older ET2 HP was playing music and listening. Here is something to consider especially for new owners. Lets say I just bought an ET2 on ebay or audiogon (or maybe five of them like Manitunc !) This is what I would do if the previous owner and yourself don't know what psi it was set up for. First the reference points we know about. From Bruce' website. ********************************************************** 3.6 PSI - 0riginal Takatsuki and ET-2 or 2.5 5.0- 7 PSI - WISA 300 air pump and ET-2 or 2.5 with high pressure manifolds >10 PSI - users with shop compressors and ET-2 or 2.5 high pressure manifolds NOTE; if the pressure readings are higher than those listed above, the manifold could be clogged, if the pressure readings are lower, this suggest that the pump may not be performing correctly. *********************************************************** That last sentence between the asterisks is very important and could be affecting your PSI. So unless you have an arm that is a custom build (meaning you told Bruce what PSI you wanted it set up for) then your LP & HP ET2 or ET 2.5 falls under one of those categories. I would select the best category that applies and do exactly what Dave did here if you read back. Lower the pressure to what your specific ET 2 or ET 2.5 will work properly at first - go up maybe one psi. Use this as a reference point in your system. Get to know its sound. Then start bumping up the pressure - if you like it great as this is all personal, room/gear dependent. Imagine Manitunc trying to figure this out with 5 ET2's. how's the leaf spring listening going Mani ? Cheers |
I took my Sony radio cassette player and placed it in front of the single mono speaker of the school record player.
excitement and thrill of hearing this music and being able to play it whenever I wanted. thanks for sharing this Richard. it reminded me of something I wanted to share also. as a kid my first music reproducer was a small hitachi am fm cassette player with a built in microphone. I discovered I could tape good songs from the radio onto cassette and play them back when I liked. Like you said - what power over the music. I was in control. So I filled a cassette tape and all I did for two weeks was play that tape. One day I decided to listen to the radio again. the same songs, when they came on the radio all of a sudden sounded..... not as good .... not like my cassette. they sounded slower and lethargic on the radio. I couldn't understand why. I would figure it out later when I was a teenager playing with turntables. Although the tape cassette player was speed stable and sounded good - it was running a little fast. so the music sounded more up beat. groovy, livelier than the slower radio version. the cassette tape was speed stable but not speed accurate. this is how I learned the difference between the two. Hi Harold - high school in 1977...me thinks you may be my lost twin ? |
Frogman: Your point is well taken and one that I failed to address: the possible differences in manufacturing processes of the wide variety of pressure guages. I do listen in a small room/nearfield which is conducive to my hypersensitivity on a wide range of issues. By the way, do you or does anyone remember the ET upgrades offered and reviewed in 1995 by Roger S.Gordon? He reviewed a (Montronix Acuflo Air Regulator). This is what I have, only the DIY version. It is way overdone for 'our' needs but the Montronix sold for I believe $400.00 then, I got the DIY for $150. In his review were the following:
Build-it-yourself-air pressure regulator
ET II Large diameter high pressure manifold
ET II Magnesium Tonearm
Damper trough
Bright Star Padded Cell
His conclusion for most Bang-for-the-Buck was the BIYS air pressure regulator. FWIW.
Ct0517: I ordered my 2.5 so many years ago and without the benifit of this forum that I couldn't tell you what mine is specifically built for. I actually emailed Bruce about this a couple of years ago and his only answer was that it is probably built for the way I'm currently using it. I guess this means no detailed maufacturer/sales info on file record. Anyway, all I know is what I hear and that's good enough for me.
Thanks again for your input on my compressor issue. By the way, as we exceed over 1000 hits here, I want the thank you for your vision and your extraordinary follow-through regarding this thread. It's easy for one's efforts to be overlooked. You are to be commended Sir! |
Slaw, I remember Gordon's article well; that's how long I have had my ET. I was always intrigued by the Motronix and a couple of years after the article appeared I searched for one without luck. What I remember the article did not make clear, other than the claimed benefits, was what exactly the Motronix did other than provide presumably more accurate control over xthe air pressure? I seem to recall some reference to it releasing some air in a controlled fashion with the supposed benefit of a smoother air supply to the arm. Can you shed some light on this? Thanks. |
Frogman and Slaw.
You planted a seed when talking about the Montronix regulator and controlled air bleed.
I have just teed off a 1/4" needle valve in between the compressor regulator and the second in line regulator.
The tee is configured such that the compressor output is fed straight to the needle valve and the second regulator is connected at right angles. Such that the air going to the arm has to turn 90 degrees.
The needle valve is just cracked open, bleeding only a tiny amount or air to atmosphere. This does not alter the pressure at the arm since there is a significant delta P between the two regulators.
If your regulators are of similar stability as mine you can expect greater solidity and dynamics and just plain better sound.
This test was done when the compressor was off so the air supply was ex the high pressure storage tank only.
Theory is that the regulator must be dithering about its setting. The needle valve, being non compensated clips the peaks of this pressure perturbation. |
I found a rare reprint or Myles Astor's TAS review of the Motronix Acuflow Air Regulator: http://www.whatsbestforum.com/showthread.php?5653-Linear-tracking-Turntables!/page3&highlight=motronixApparently, two of the people involved with designing and reviewing this unit are still involved in audio. Miles Astor, PhD is Senior Assistant Editor at Positive-Feedback Online and Marlen Mogilever, PhD, who is mentioned in the TAS article as being "of Motronix" is now the principal designer at Blueberry Hill Audio: http://blueberryhillaudio.com/index.htmlAfter reading the TAS article, I realize that this unit was more involved than what most of us are now using, i.e. two spring/diaphragm regulators with a surge tank in between. I wonder if we contacted one or both of them that they could/would give us enough detail to be able to reverse-engineer the Motronix unit or, at least, to mod our existing setups to duplicate the Motronix unit's functionality? Dave |
Received my ET package from Bruce yesterday.
Will post up pictures over the weekend of my air set up along with the ET-2.5 on my system page. |
Richardkrebs and readers of this thread, My apologies to all for not having responded earlier, neurosurgery has precedence. Richardkrebs has been advocating changes to the ET2 that include adding mass and removing the patented decoupled counterweight. These suggested changes take the ET2 outside of its designed operating parameters. In February Richardkrebs promulgated a theory that adding 30g+ of lead to the ET2. He also advocated removing the decoupled counterweight and changing it to a fixed counterweight assembly. He claimed that this was a big improvement on the performance of the ET2 with low compliance cartridges. Richardkrebs claimed to be the only authority on adding lead mass to the ET2. Richardkrebs claimed that adding lead mass and removing the decoupling gave a flat frequency response in his listening room. To recap… Richardkrebs on adding mass: 02-15-13: Richardkrebs
I have added a lead slug inside the bearing spindle 25 mm long with its OD equalling the ID of the tube…
This combined with the fixed counterweight means that the arm is HEAVY in the horizontal plane. I have tried magnetic dampening and oil troughs but prefer the pure mass approach. I run at around 12 psi, lower pressures may be problematic when adding so much mass.
03-03-13: Richardkrebs
For those of you who may be interested in adding mass. I would bring your attention to Morch's latest arm which uses massive weights to increase horizontal mass.....Extra weight like this would dwarf the 30 or so grams I have added to my ET. NOTE : This post demonstrates a lack of understanding. Removing the decoupling of the counterweight also increases that horizontal mass that the cartridge sees and therefore the total increase in mass would exceed the 30g claimed. 03-04-13: Richardkrebs
I have tried both light and heavy ETs. As far as I can tell, I am the only one who has done that. If so, I am the only person here who can speak with any authority on the subject. Richardkrebs now claims that he has NOT added 30g off mass after all, and that his arm is close to the standard weight. 12-09-13: Richardkrebs
My ET spring a leak, actually one of the o'rings failed. This necessitated disassembly. I took the opportunity to give it a spring clean and weigh it. Total weight excluding cartridge was 86 grams (95 grams with cartridge). I have on loan a standard I beam, counter weight assembly (thank you Grant) this weighs in at 47 grams, excluding the spindle clamp. This would put the total weight of a standard ET2 up to 77 grams with an aluminium wand and 85 grams with a magnesium wand. It is my intention to revisit the use of a sprung counterweight.
12-10-13: Richardkrebs
The 30 gm adder was a guess based on 16 year old memory. Clearly my guess was well overstated. I will be removing this when I do the swing arm counterweight test to bring the arm as close to stock as possible. The 95 gm total, arm and cart weight, is accurate. This depending upon c/weights and cart used by others, being more or less the same as a standard ET2 using a mag wand. It would appear that the sonic benefits Richardkrebs proclaimed, accompanied by much mathematical conjecture over the past 10 months, are not attributable to adding lead mass as Richardkrebs claimed, and that the benefits of adding lead mass, if any, exist only in his head, in theory, as they have not in fact been trialed. With regard to the Morch analogy, this is speculation and assumptive on his part by his own admission. Rotational inertia is quite different to linear inertia and I’m not sure how one could possibly use a pivoted arm model to explain the forces involved in a linear tracking tonearm. For what its worth, I too have experimented with lead mass. I made a lead slug, 25mm long and fitting the ID of the ET2 as per Richardkrebs suggestion. Excluding the string and glue, the mass varied from 26gm to 34gm depending on how tight the slug was wound. Richardkrebs now claims that his arm is only 7gm heavier than standard. I cannot replicate his new claim of a mass differential of 7g with the size of lead slug he advocated. 05-15-13: Richardkrebs
My calculation of weight delta was based on how much weight the air bearing has to carry Clearly Richardkrebs calculations were incorrect since he has not added anywhere near the amount of lead mass that he believed he had. Richardkrebs on removing the patented decoupling system on the counterweight: 03-25-13: Richardkrebs
I know that BT designed the arm to have the two spring systems, Cart and Counterweight. I just don't think that it is a good idea….
02-17-13: Richardkrebs
I did my initial tests on extra horozontal mass by disabelling the leaf springs on the counterweight beam
03-20-13: Richardkrebs
The thought that there may be more going on with the decoupled counterweight was triggered by your post where you quoted BT where he said that the ibeam had a natural frequency of 2-5 hz.
This is close to the resonant frequency of the arm itself. This could have performance implications.
03-21-13: Richardkrebs
If fixed, the counterweight beam must be very strong…. Three springs don't cut it.
It is no accident that other arm manufacturers have a rigid joint there....it simply sounds better.
03-25-13: Richardkrebs
Has anyone thought about why the CW spring(s) and their damping are so fussy to set up?
My prime reason for fixing the counterweight is to restore the full bass drive….
04-16-13: Richardkrebs
When I fixed the CW and added further mass and used a low compliance cart, there was an unexplained positive side effect. Focus and sharpness improved. Transients were better. It was some years ago when I made this change and while liking the improvement, I didn't put too much thought into 'why'.
I will not be degrading my arm by converting it back to standard form. From Richardkrebs posts it would appear that he removed the decoupling spring, but did not understand the implications. Bruce’s testing on the Eminent Technology website demonstrates a rise in low frequency resonances if the decoupling is removed. Despite this Richardkrebs clearly states that he disagrees with Bruces ET2 design goals of maintaining a low horizontal mass and using a bifurcated spring to split the resonant frequencies to minimize resonant peaks in the low frequencies. Here is an extract from Bruce’s patent on the ET2. The damped leaf spring 39 is oriented so as to allow horizontal motion but prevent vertical motion, i.e., decoupling, of the counterweight arm 37 and counterweights 38. Decoupling is necessary to reduce the effective mass seen by the cartridge 36 in the horizontal plane which allows the use of high compliance cartridges 36. The stiffness of the damped leaf spring 39 can be increased to allow higher horizontal mass to match low compliance cartridges 36. The damper material for the leaf spring 39 can be an elastomer. Damping provides the desirable quality of little or no rise in amplitude at resonance horizontally. Also separate horizontal and vertical resonant frequencies can be achieved by decoupling only in one plane of motion. Removal of the spring decoupling will increase the resonant peak – Bruce measures 6db plus. If you go though the Shure white papers on low frequency resonance, they confirm this – they measure resonant peaks of 6-20db that increase motion 2 to 10 times. From the Shure white papers - what happens at the resonance frequency? One important characteristic of resonance is that motions are magnified considerably, in this case, typically from 2 to 10 times.
In both situations, the output from resonance frequency signals in the groove will be increased from 6 to 20 dB. These numbers are just the dB equivalent of the magnification numbers previously mentioned. By itself, this may not be all bad, since this resonance peak determines the low-frequency response "limit" of the pickup and system, and a bit of boost here may not be unpleasant. This was certainly true fifteen years ago, when arm resonance frequencies of 30 to 50 Hz were common. However, with modern pickups and arms, these resonance frequencies are usually subsonic (below 20 Hz), so that reproduction by the loudspeakers may cause distortion. Additionally, preamp overload is most likely to occur at boosted low frequencies since the preamp clipping level is lowest here. Consequently, the arm resonance has lost whatever usefulness it once had and must now be regarded as a liability.
The most pernicious effect of the resonance is shown in Figures 1 and 2 by the "scrubbing" notion developed by the stylus in the groove. This causes program material to warble in pitch, just as if the turntable speed were fluctuating. In fact, the groove speed is changing (relative to the tip), because a fraction of the velocity of arm vibration is added to the groove velocity. (See Appendix I.) The effect is that about 1/3 of the arm vibration velocity is alternately added to and subtracted from the groove speed. For example, at arm resonance, total amplitudes of 1/32" are easily observed by eye. If the frequency is 8 Hz (typical for high compliance pickups and average arms), the resonance velocity will be about 2 cm/sec (see Appendix II). This velocity will produce a "scrubbing" velocity of 0.6 cm/sec along the groove axis. The groove speed at a 4.5 inch radius is about 40 cm/sec; so the frequency modulation will be about 0.6/40 = 1.5% and easily audible.
Another less obvious consequence of the arm resonance is that the stylus force is "used up" when the arm is vibrating. In the previous example, if the compliance of the pickup is assumed to be 20 x 10-6 cm/dyne, 2.0 grams of stylus force will be required to accommodate the arm vibration alone. This is larger than the usual stylus force, so mistracking is quite certain at the extremes of the vibration. Clearly the removal of the decoupling has negative impacts on both tracking and increased distortion in amplifiers and speakers from the infrasonic distortion generated by the cartridge/arm resonance. Use of Fluid Damping Again there are more contradictions in Richardkrebs posts - 02-18-13: Richardkrebs
I do not like the effect of the oil trough.
05-05-13: Richardkrebs
Twenty years ago I made a oil damping trough for the then standard ET2, mounted on a Goldmund Studio.
installed it on the current arm. Nice changes to the blackness of the background. The system is even quieter. As a result, it doesn't seem to extend dynamics upwards but downwards further into the low level detail. A very agreeable effect. Also greater presence and focus. It will be staying. . Richardkrebs on Stiffness of the Air Bearing 04-21-13: Richardkrebs
....the air bearing employed on these arms is effectively rigid at audio frequencies. So they should look elsewhere when looking for the cause of compromised note leading edge performance. . This is a very good example of conflating physics and mathematics. Frogman, Ct0517, DGarretson, Slaw, myself and many others hear significant differences in performance when adjusting the air pressure on the ET2. Having studied structural, mechanical and materials engineering and physics at university, my view is that altering the air pressure will alter the performance of the arm – either altering the rigidity and/or altering the resonances within the air bearing. I quote Ralph Karsten of Atmasphere producer of valve amplifiers, and who has considerable experience producing and cutting records. 01-17-12: Atmasphere
If LPs were perfectly concentric like they are supposed to be, I can imagine that having a high lateral tracking mass would have its advantages. But in real life, concentricity is something that we hope for and often come very close to getting, but its not perfect. IOW the arm does need to negotiate such imperfections in the LP. I imagine some of the issues can be tuned out with the leaf-spring device mentioned earlier- so does that mean that you have a different setting depending on the LP?
One other issue of air bearings I forgot to mention is the coupling that needs to occur from the platter surface to the arm tube of the arm. The idea is that the arm and the platter move together as a single unit. That is to say that if there is air-borne vibration, it affects the platter in the same amplitude and phase as it does the base of the tone arm. If there are differences between the two, this will be heard as some sort of artifact, IOW it becomes something that the cartridge can react to. This is why the plinth can have such an affect on the sound of the 'table.
When you have an air bearing, this coupling is not as profound as it should be. One of the demonstrations that this is a very real phenomena is the fact that as you increase air pressure in the bearing (increasing coupling to the base) the arm sounds better. When I questioned the stiffness of the bearing in relation to the added mass Richardkrebs advocates, he responded - 03-19-13: Richardkrebs
Re quality factor, Q. ... under, critically or overdamped systems, as they relate to the ET2. My running the arm at 12 psi is no accident. I addressed the Q factor of my arm years ago. And the bearing has no issues at all carrying the extra weight, even at this pressure. And yet now he says he is running 18psi. 11-05-13: Richardkrebs
The output is fed thru two regulators in series, bringing the pressure down to 18 psi for the arm. . In summary then, despite having owned the ET2 for over 25 years, it would appear that since February this year - Richardkrebs has advocated adding lots of lead mass, and claimed many benefits, but now claims that his ET2 arm mass is close to standard. Richardkrebs has proclaimed that Bruce’s decoupled counterweight is not a good idea, and stated in April that putting the arm back to standard will degrade the sound. Now, in December, Richardkrebs is not sure and is going to retrial the decoupled counterweight. For 25 years, Richardkrebs eschewed fluid damping, but now believes it is of benefit. Richardkrebs claims the ET2 air bearing is rigid at audio frequencies and 12psi was the optimum air pressure for his set up, having carefully calculated Q. Now he has moved up to 18psi without an explanation. These contradictions outlined above, demonstrate a lack of scientific rigour in testing and set up. It is not an approach that one would recommend. It would appear that Richardkrebs has much work to do to determine the optimum set up for his ET2. My suggestion would be for him to put his arm back to standard and set it up as per Bruce Thigpens’ ET2 manual, assuming he now has some understanding of how it works. For your reference here are links to the Manuals and Patent http://www.patexia.com/us-patents/04628500http://www.eminent-tech.com/main.htmlSeasons greetings to all.. Dover |
Richard, interesting comments. Eventhough I settled on 18.5 -19 psi (at the arm) based on what my ears tell me sounds best in my system and not simply what my HP manifold was designed for, that pressure is (coincidentally?) about .5 psi above the pressure at which the check valve on my surge tank starts to release some air without fully opening. As the pressure is increased further the released air increases until the spring loaded valve opens fully (at about 20.5 psi or so AT THE SURGE TANK). Makes me wonder if the reason the arm sounds best at that pressure is not only that it is the ideal pressure for my arm, but also that the released air has a similar effect as what the Motronix accomplishes. Thoughts? |
Frogman.
I suspect that the check valve you refer to is actually a safety relief valve. And yes it could be the same thing that I am hearing.
It may have an adjustment so you could, entirely at your own risk :-) increase its setting to see if the bleed flow could be stopped but still maintain the same pressure out of the regulator and on to the arm.
Obviously I don't know what your surge tank can take in terms of max pressure, so be careful should you decide to do this.
I read the TAS review and this could be a review of the changes I hear in my system. It is a significant jump in performance and ultra easy to do.
The dimensions given for Motronix unit would imply that any surge tank, if included, would be very small indeed. So maybe it is simply two high quality regulators with a central bleed?
It shows how sensitive the arm is to smooth air delivery. As per my earlier post, the compressor had cycled off, so the air supply was coming only from the reserve in the tank. The "noise" in the air stream could only be coming from the regulators and the associated hosing to the arm. |
Richardkrebs, yes, safety relief valve, I have always incorrectly referred to it as a check valve. Interesting proposition. My DIY PVC tank can handle the full output of my Medo compressor which although rated at 22psi can actually output close to 30psi. Dave has the same compressor and it outputs 32 psi. Prior to installing the relief valve I tried higher pressures (without controlled air bleed) but I did not like the sound which would take on an overly lean and rather tense quality. I settled on 18-19 psi for best sound. I don't think that the relief valve can be adjusted, but it would be interesting to hear what higher pressure with controlled air needing sounds like. |
Received my ET package from Bruce yesterday.
Will post up pictures over the weekend of my air set up along with the ET-2.5 on my system page. Hi Rugyboogie your Christmas present hath come early..no? You must have been really good this year But aren't you supposed to wait until the 25th to open the box ? :^) They say its better to give than to receive; if so BT must be feeling pretty good this year. Congrats and looking forward to your impressions. Cheers |
Dover: lack of response by yourself was not noted.
Further, whispers suggest all here join with you, and hope that any further neurosurgery you have is successful. |
Dlcockrum: Thank you for the posting of the MA article.
On a different note... My system is sounding absolutely awesome! I hope this is a sign for things to come in this new year. |
Hello gentlemen,
Very interesting thread.
I would like to ask, what kind of air pressure regulators are you using for the arm ?
Ultra fine air regulation (specially at low pressures) is better done with diaphragmatic regulators. They do have incorporated bleeding system. This is a nice one:
http://www.ebay.com/itm/SMC-ITV1050-311L4-X26-PNEUMATIC-ELECTRO-REGULATOR-/140916413771
But there are passive ones with same performance. |
Hi Cabbiendi I would like to ask, what kind of air pressure regulators are you using for the arm ? I hope others chime in as well. I use three regulators. The first two are inside the Timeter compressor pump. http://mercurymed.com/catalogs/RDR_Compressors_Accessories.pdf?phpMyAdmin=8bad005e4170814880e9a1aebf2262f1The main regulator in there, can be seen in the manual link below on page 5 - part no. 13. Part 21 is the tube that drains moisture like a cars ac system. http://www.alliedhpi.com/images/zs168-263-002.pdfIt is a 50 psi patient respirator and has been a top turnkey air system for me for many years. this compressor/pump runs all the time. I take 19 psi from it down the line 100 feet of tubing and the rest of the psi escapes into the air at the pump through a regulated T valve. The separate in room regulator is located next to the ET 2.5. http://cgim.audiogon.com/i/vs/i/f/1301961480.jpgThis one I know is a diaphramatic regulator / air filter and water container. I can say because of the quality of the timeter - I never see a drop of water in this regulators bulb. I have a choice to use this in room regulator, as an actual "regulator", or to open it (top knob) so it just acts as an air filter / water trap. Ultra fine air regulation (specially at low pressures) is better done with diaphragmatic regulators.
But there are passive ones with same performance.
Cummins Hydraulics - where I bought my in room regulator told me the industry considers anything up to 125 psi as low pressure. Are you in the hydraulics/pump business? Can you provide more info or insight ? Welcome to the thread. Cheers Chris |
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Hello Chris,
Thanks for your detailed answer.
I have always been in the ophthalmic industry. In this field some processes are very delicate and require dry air at a very specific pressure.
For such applications we always used diapragmatic air perssure regulators. They indeed expel air through small nozzles to regulate at a very fine level. Standing close to them you can listen the air bleeding out of the nozzles. They are not noisy but I'm not in the condition to say they can be installed inside the listenig room.
Reading the post of Frogman (Dec 12) I imagined that his relief valve could be acting as a bleeding nozzle giving a finer level of regulation, but I do not know.
Chris, I am not sure your in room regulator is diaphragmatic. They look flatter and I never saw one of them with water separator and filter.
Anyway, if I understood well you have a loop system taking 19psi out of the 50psi mains and the overpressure go back to the compressor..?? This is an smart design.
I never had an ET tonearm but I have the highest respect for this design. To me, it can compete against any tonearm. Until I found this thread I sincerely never imagined the air pressure could be so important.
Regards,
|
Hello Chris,
For some reason, my first answer was not shown.
Thanks for your detailed answer.
I have always been in the ophthalmic industry. In this field
some processes are very delicate and require dry air at a very specific pressure. For such applications we always used
diapragmatic air pressure regulators. They indeed expel air through small nozzles to regulate at a very fine level. Standing close to them you can listen the air bleeding out of the nozzles. They are not noisy but I'm not in the condition to say they can be installed inside the listenig room.
Reading the post of Frogman (Dec 12) I imagined that his relief valve could be acting as a bleeding nozzle giving a finer level of regulation, but I do not know.
Chris, I am not sure your in room regulator is diaphragmatic. They look flatter and I never saw one of them with water separator and filter.
Anyway, if I understood well you have a loop system taking 19psi out of the 50psi mains and the overpressure go back to the compressor..?? This is an smart design.
I never had an ET tonearm but I have the highest respect for this design. To me, it can compete against any tonearm. Until I found this thread I sincerely never imagined the air pressure could be so important.
Regards, |
Hi Cabiendi In this field
some processes are very delicate and require dry air at a very specific pressure. An interesting comment. thanks for sharing. The quality (dryness and cleanliness) of the air is very important to the tonearm since the pores that allow the air through to elevate the air bearing spindle, can start accumulating water mineral deposits, other particles .. carried by moisture; thereby reducing the effectivness of the tonearm and the pump. The arm is also designed for very easy cleaning. Anyone buying a used ET2.0, or ET 2.5 or having run one for many years should be performing this procedures documented in manual. Being successful (meaning getting the best sonics) with an ET2, ET 2.5 entails becoming familiar with its parts, and the way it works. this is my opinion after 10 years. I am not sure your in room regulator is diaphragmatic. They look flatter and I never saw one of them with water separator and filter. My in room regulator normally doesn't come with a water container and filter. I purchased the filter/bulb separately with the appropriate threading to attach to it. I am in the business of business contingency planning / business continuity. The processes involved have made me somewhat anal in regards to backup systems . :^) Its ingrained in me that you just can't have enough of them. http://www.xmc-pneumatic.com/products/HAW-Series-Air-Filter-regulator-1082135.htmlModel aw2000 I could get a smaller regulator one that would put the 19 psi into the middle range for the regulator, but this one has been working well and the smaller one had to be special ordered. I am told by the shop that uses and sells it, I verified yesterday that it contains a spring and diaphragm. The other thing we need to remember with both the ET2 and ET 2.5. Both use only a percentage of the incoming air to work as designed; the rest gets bleeded out around the edges of the manifold. The air has to go somewhere. As has been discussed here they are a captured air bearing meaning air circulates the air bearing spindle 360 degrees. So when we discuss a bleeding effect in the air supply - the tonearms themselves are also designed to release air as part of their design. Bruce has confirmed this to me in previous discussions. Placing of a draft detector near the tonearm parts should allow one to see how the air is released and if there are any leaks near the bolts themselves. Cabiendi - your perspective from an ophthalmic industry view is very interesting. thank you for your insight and I look forward to more input from you. Cheers Chris |
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Ok, you guys are a bad influence... I just bought a used, ugly ebay Timeter Aridyne 3000. It seems to make air ok, so now I need to find adapters for the air outlets... where to get?
Should work better than my little hobby airbrushing pump. Probably quieter too.
BTW, I found 19 psi to be the sweet spot for my 2.5 too!
TIA!
Greg in Mississippi <- has 2 ET's, a II and a 2.5, both with high-pressure manifolds. Phono's been down for years, excited to be doing something to get it going again. |
Greg in Mississippi - welcome to the thread and Audiogon ! Another Multi ET2'er ....... the timeter ugly ? Well I guess...but I prefer the word industrial looking :^) so now I need to find adapters for the air outlets I am using a Schrader Bellows Adapter on top of the TImeter. http://cgim.audiogon.com/i/vs/i/f/1390344387.jpgLooking at the pic on the right. Turning the knob allows me to control humidity and psi levels at the pump itself. Where to buy. http://www.parker.comClick on where to buy. Select Locate by Brand Name. Select Schrader Bellows. Follow remaining prompts for your zip code. It should come up with the places closest to you. or If you google "Mississippi Hydraulics Pneumatics" it should provide a list of places near you also for similar regulators. I recommend bringing the whole pump into the store for three reasons. - So you can watch their faces when you open up the back panel and they see what kind of compressor/pump it is. - So you can watch their faces again when you tell them what you are going to use it for (priceless) - With pump in the store they should be able to match up adapters that will work and connect them for you so you are sure. Let their expertise guide you as long as they know how you will take some air from it. If any questions you can contact me at bcpguy (at) bell (dot) net Cheers Chris |
An ET2 base model from France. Mais Oui! aucune affiliation à l'annonce (no affiliation to the ad) |
Hi Greg here is the info on the Schrader Bellows part I referenced earlier in case you decide to pursue it. I called a random dealer to see if the part was available, in case a dealer was not available near you. Cheers.
Chris,
For the Schrader bellow part, 3381101, I found a part, 003381101, which is a ¼” needle valve. The price is $28.20 each and has a 10 day lead time. If this is not the correct part or you have any other questions feel free to email me back.
Thanks,
Stephen Kretz
Ohio Belting & Transmission Co. | Customer Service
(419) 535-5665 x 119 Business
|
Thx for the info and legwork. That'll be very helpful.
I pulled the fitting off the top outlet and will try a few possible options this afternoon.
One thought... is it better to run the 50psi into a surge, then regulate it down, or regulate first, then surge tank? I have a couple of heavy-wall PVC pipe surge tanks and did have them upstream of a regulator in the past, so they can take the pressure.
Yah, I do already have a regulator, but I'm planning to setup both arms in separate systems and will want a 2nd one. I prefer to have the regulator near enough to the system where I can see it and adjust if needed. So I'll use the contacts you sent to get the 2nd one.
On the pump being ugly, I wasn't joking... it had seen some use, see here: http://www.ebay.com/itm/330896465118?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649 .
I found the maintenance manual and opened it up... all of the sound-deadening foam is crumbling, need to find replacement. And the pump may not be fully secured on its mounts... will look at it closer this weekend and start some R&R on it.
I not only have 2 ET, but started with an ET-I back in the day! When I got that, I knew I had the arm I'd die with!
Greg in Mississippi |
