Eminent Technology ET-2 Tonearm Owners

To clarify, I mean to say that at LOW pressures approaching the threshold of mistracking, the bass comes up and musical presence improves.

Been thinking about the "air escaping" issue. Seems to me that what has not been made clear enough is that there will be air escaping no matter what the pressure is. While it is obviously true that an air bearing will be optimized for a specific pressure range beyond which some of the mentioned issues concerning resonance may occur, we also know that dealing with resonance is a tricky issue and a bit of a black art which involves the rest of the system (specific cartridge and its resonance characteristics, and even things like how much torque one uses to tighten the adjustment bolts on the arm). Clearly, there will be a point when too much, or too little pressure, will be simply too much/little, but I believe that there is a fairly wide range beyond the "design ideal" which is "system" dependent and which, as always, is determined by what simply sounds best.

Someone explain to me how in a "captured air" bearing design air will NOT escape regardless of the pressure delivered to it. I think that when we talk about being able to hear it, it is simply that, the point at which it becomes audible; not that there is no air escaping prior to that point.

Dgarretson - The air pressure at this threshold depends on the weight of the selected wand and counterweights.

Dave G - thanks for that interesting info re: Trans Fi tonearm.

Would it be correct to assume an owner of a Transfi needs a pump that is variable in its PSI for the different arm wands and cartridges ?

With the ET2, ET 2.5 one psi is used it does not change as the Spindle/Manifold remains the same. Different armwands and I Beam adjustments - single, double, triple springs are made for the different cartridges.

yes two very different designs.

Frogman - Someone explain to me how in a "captured air" bearing design air will NOT escape regardless of the pressure delivered to it. I think that when we talk about being able to hear it, it is simply that, the point at which it becomes audible; not that there is no air escaping prior to that point.

Frogman - I remember talking to Bruce about this some years ago.
I sent him an email and also confirmed things in a call this morning.

The ET2, ET 2.5 is a captured air bearing system meaning

"Air surrounds the spindle in a circle 360 degrees"

I did ask him about the type of air bearing tonearm that uses a cup bearing which is floated.
We did not reference the Trans Fi or other tonearm just the type of design.

- his response to me on the phone-
the more air and it will become floppy. So just enough air to float is required - supporting what Dave G said.

*************************************************

Some more information - this was from my actual email - his response in quotations.

Hello Bruce

I have two general questions.

If we use my ET 2.5 as an example that you set up for 19 psi. A continuous 19 psi air flow is sent in. Can we assume the spindle uses all 19 psi to work optimally (or is it a percentage of this amount)


"The manifold is optimized for the design pressure, the pressure at the surface of the spindle is a percentage of the inlet measurement, this is by design."

If someone has a 20 year old stock ET2 designed for about 3 psi and decides to pump in 15 psi. The extra air will just escape around the edges of the manifold and at a rate that can be heard ?

"The extra air will escape, but the rate of escape will not be that large from an operational point of view, but the escaping air is usually audible which causes one problem and the air can cause a push back at the extremes of travel. "

*********************************************

Bruce really like the idea of the pump test.

I then asked him about all the ET2's on ebay and other sites that people are buying used - many come with no pumps. His advice was to start low with them 3 psi and go up. Whatever PSI it takes to float the spindle properly and work is the PSI that should be used.

A case in point my ET 2.5 is designed for 19 psi. I told him if I start lowering the PSI it will start mistracking a few PSI below that. He confirmed this and this is by design.

I would think that the favorable qualities of a captured air bearing in this application are maximum bearing stiffness(a function of air pressure) and minimal air turbulence(a function of air velocity through the bearing and surface friction.) The best one should have the tightest clearance in order to minimize air loss and turbulence attendant with velocity.

In contrast, the stability of the Trans-Fi bearing is not a function of stiffness, but rather of aerodynamic balance. It functions like a glider wing that requires only the minimal air pressure and flow to obtain lift. It operates in a horizontal plane, rather than in 360 degrees as with a captured air bearing. The air velocity through the bearing is higher than with captured air bearing, but as air pressure is low, turbulence is minimized. In this particular instance, the more pressure, the higher the lift, the sloppier the bearing.

Chris, Trans-Fi needs only a 4 psi aquarium pump, smoothing tank(s), and a good brass needle regulator. No need for an evaporator tank, given the small 2-3 psi differential between the pump and the tonearm. One may be tempted to think of it as a poor man's solution, however in my view its design has fewer problems to solve than a captured air bearing and illustrates the virtue of KISS.

Chris, thanks for Bruce's comments. It all makes complete sense, however my question is still not answered. I suppose its academic, but as a point of interest, I fail to see how air would NOT escape regardless of pressure. Air (like water) under any amount of pressue will choose the path of least resistance, so even though the air delivered at the "ideal" pressure will "surround the spindle 360 degrees", some air will still escape out of either end of the spindle; there is no gasket or blockage to stop it.

Re Dave's comment about air bearing stiffness: with my HP 2.0 bearing and Wisa pump, if I push on the spindle sideways, it takes very little force to cause the spindle to rub inside the manifold. With the Medo delivering 17-19 psi at the arm (yes, it will do that), it takes a considerable amount of sideways force to cause it to rub. The bearing is MUCH stiffer with the Medo, with a resulting major improvement in sound; particularly in the areas of dynamics, bass tautness and speed, and soundstage detail and stability.

Hi guys,

I talked with Bruce yesterday. My 2.0 HP manifold is two weeks off. There are no 2.5 manifolds nor setup jigs available right now, but there are tentative plans to make a production run of both in the next 6 months or so. Bruce confirmed that the 2.0 HP manifold is a better match for medium/high compliance cartridges and the 2.5 is a better match for low compliance carts (difference in horizontal effective mass with the 2.5 being heavier as noted previously in this thread).

We discussed the topic of air pressure and air escape. My interpretation of the conversation is that it is normal to be able to hear some amount of air escaping from the bearing and also to be able to hear a low-level air noise at high volume with your ear to the speaker (Chris's pump test). The amount of air escaping and thus the audibility will increase with higher air pressure for a given bearing clearance, consistent with my experience.

After extended listening comparisons, some including my golden eared wife, I have decided that changes in air pressure are audible (similar in scale to VTA changes) and our preference changed with the recording. Keep in mind that this is with the stock 2.0 manifold. Some instruments within the soundstage move forward at higher pressures, creating a better delineated front-to-back separation, but the overall sound is less relaxed and natural, with a change for the worse in tonal balance, particularly on piano. Ended up back at 3.6 psi (at the arm) for best overall performance with the stock manifold. Bruce has said this to me consistently over the years and, being the hard-head that I am, I had to prove it for myself and finally have the proper quality and control of the air system to feel confident in this conclusion.

As always, this is MY preference in MY system and YMMV. I feel certain that all this will change with the introduction of the HP manifold, where the smaller orifices and tighter bearing/spindle clearance will eliminate the downsides described above at higher pressures and further enhance dynamics, bass performance and soundstaging as Frogman describes.

Dave

Hi Dave - I am looking forward to your impressions of the ET 2.0 HP manifold. Cheers Chris

from the Audiophile Club of Athens.
A very interesting website with a lot of audio passion like here at Audiogon.
I came across a recent visit with a member with an ET 2.5 on a Micro Seiki table.
He also has an SME V and ZETA tonearm on the same table.

To see the ET 2.5 in action for a bit, scroll to the bottom of the page for the video.

http://www.aca.gr/index/meetings?row=2320

to Kyriakos (owner of the ET 2.5)

If by chance you happen to visit Audiogon, please stop by and say Hi to us here !

Cheers

Chris, this pertains to an earlier discussion about identifying a 2 vs a 2.5. Look closely at the pictures of the ET. I would bet one of my extra arm wands :-) that its a 2 not a 2.5. The HP 2 is sometimes mistakenly referred to as a 2.5. Regards.

Hi Frogman - it does look like an ET2 to me - but I took my reference from their website directly.

Mikro Seiki RX-1500 FVG turntable with three arms and cartridges that were, SME V arm and Dynavector XV-1S Ruby, ET2.5 arm and Dynavector XV-1T, Zeta arm and Kiseki Purpleheart Sapphire.

The HP 2 is sometimes mistakenly referred to as a 2.5

Oh I agree - and does another audio product exist - that in pictures is so easy to mistake I ask ?
In person they are very clear.

does another audio product exist - that in pictures is so easy to mistake I ask ?

I guess I really meant to say "tonearm" instead of audio product :^)

Skill testing question - this is for non ET2, ET2.5 owners only.

Halcro? Nikola? DG ? Lew? Banquo363, Timeltel ......... Syntax... I am calling out to you too....all others?

In this picture which is the 2.5 and why ?

http://cgim.audiogon.com/i/vs/i/f/1384998156.jpg

Too easy. I will let the others chime in :-)

Oh, wait! You said non–ET users. Sorry.

But, Chris, you should know that if I ever have a question about the ET arms, I would ask you. So asking me to identify one is like asking yourself ;).

Welcome to the thread Banquo... touchee!

Firstly - I am not certain of the answer myself (well it would be a guess) based on pictures themselves, especially when just one ET2 is shown.
Frogman is able to tell the difference from pictures. I think he is using the armtube as a reference ?

But the picture I posted shows only two manifolds and spindles only - no armtube.

Pictures are an illusion (sort of like this hobby?) of camera angles and scale.

imo - this is very similar to fishing, in that if a fisherman wants their fish to look bigger in the picture - they hold it out "in front" instead of to the side of them to show proper scale.

Of the two shots that are in that pic of my last post.

Here is a hint.

One of them is smaller in scale ?
Yet the spindle still appears to be the same size as the other one ?
For non-ET2 owners following the thread the answer should be clearer ?

Another hint (when no arm wand is visible):

Look at the width of the portion of the manifold housing (where the lettering is printed) that extends beyond either side of the length-wise "edge" of the spindle tube. Or, look at the same "edges" in relation to the lettering on the manifold housing. Either way, which tube's diameter is wider will be obvious.

Okay, guys, how 'bout some MC cartridge recommendations for mating with my ET Two. I'm currently using my tried-and- true van den Hul MC Two HOMC (2.25mV output with vdH 1 stylus). I really like the sound of this cartridge with the ET Two (transparent, fast, dynamic, and ballsy) and the vdH 1 stylus is the quietest in the groove of any stylus I own and is claimed to last for 3000+ hours. Just testing the waters to see what is out there that would be better.

My requirements are:

1. must be an excellent match for the ET Two with the base aluminum armwand
2. 0.5mV or greater output (.65mV or higher would be preferable)
3. cartridge weight <10g (the lighter the better)
4. selling price <$2k
5. <250 hours if used or freshly retipped/refurbished
6. must sound significantly better than my vdH MC Two (this cartridge is tragically under-publicized and under-rated IMO)

I listen mainly to acoustic jazz, blues, rock, and a little classical. You can see associated equipment in my "System" link.

I have been eyeing a Colibri XCP HO for sale here on Agon right now:

https://app.audiogon.com/listings/cartridges-van-den-hul-colibri-high-output-as-new-excellent-condition-2013-11-17-analog-Netherlands

This one meets all of the above criteria, but I am a little spooked of the Colibri due to some horror stories I have heard about its fragility and quality problems with recent vdH retips/rebuilds, plus I can find nothing on the web about it's compatibility with the ET Two or similar air bearing arm.

If I can't find something that meets all of my criteria, I will just stay with the MC Two, which is probably what I should do anyway ;^).

PS: I also have a nice stable of MMs: Empire 4000D/III, Signet TK-7LCa, Sonus Gold Blue, Micro Acoustics 530mp and 2002e, Astatic MF200, ADC XLM II Improved, and Shure V15 Type III MR. I read that some of you have liked the Empire with the ET Two. Is that still your opinion? What about the others?

Dave

Keep in mind that all the cartridges you own are fairly high compliance; including the VDH which is high compliance by MC standards. The "base aluminum arm wand" is well suited to higher compliance cartridges. Most MC's are lower compliance which means they will send more energy into the arm wand; a higher mass wand such as the magnesium wand would be a better match for most MC's.

Having said that, I have gotten excellent results with my ET2 (magnesium wand) and a Shelter 901. The Shelter's stated .5 mv output plays considerably louder than my VDH's stated .65 mv. It is dynamic, robust and full sounding with a richer and more romantic tonal quality than the VDH's which leans toward a whitish/gray tonal quality (in my set-up, of course). Definitely worth trying.

Hi guys, a classic Air Tangent on AudiogoN: http://app.audiogon.com/listings/tonearms-nos-air-tangent-tonearm-linear-air-bearing-tonearm-2013-11-12-analog-29732

Is there anyone who has experienced an AT ? Frankly, I was searching for it and a Forsell 5 years ago (I didn´t know ET-2´s excistence at the time) but I suddenly found the Trans-Fi arm and bought that immediately... and saved a fortune ;). It has proved to be the very best audio bargain in my history. The ET-2 is another very interesting tone arm though.

Dave G, have you got an ET-2 already ?

Thanks as always, Frogman. I found a decent deal on a new Shelter 901 Mk II. Several reviews and owner posts say that the Mk II has similar tonality but incrementally better overall sound quality and a slightly higher output (.55mV) compared to the original. I am surprised that Shelter uses a .3 X .7 elliptical stylus on the 901. Care to speculate on the compatibility (sound quality/tracking performance) of a Shelter 901 Mk II with the aluminum armwand?

Dave

Dave,

Prior to my buying the magnesium arm wand I used the regular aluminum wand with various MC cartridges including some that were much more "aggressive" than the Shelter including the Spectral, VDH Grasshopper and others, with no issues that I could definitely attribute to the aluminum wand. I think you would be fine with the aluminum; you can always easily add additional mass and/or damping to the wand. I will say, however, that on Dover's recommendation I went back to the aluminum wand when I started using MM's again with beneficial results. You can extrapolate from that experience. In general, the Shelter behaves very well in the ET2 with well controlled highs. The issue of output is curious. The Shelter plays almost as loud into my EAR phoo stage as a Benz Ruby H which has an output spec of .8mV @ 3.54 cm/sec; go figure.

The easy way to tell if you are looking at an ET2 versus a ET2.5 ?

To be so obvious that it is over looked ?

We need to draw our attention to the end cap holding the counterweight assembly.

On the base ET2 the end cap clearly overlaps the skinnier spindle.

On the ET 2.5 the cap will appear flush with the spindle as the wider spindle has an aluminum insert that the end cap couples to.

Cheers

On the base ET2 the end cap clearly overlaps the skinnier spindle.

http://www.ebay.ca/itm/Eminent-Technology-2-Tonearm-/321252202495?ssPageName=ADME:B:WNA:CA:3160

The overlap of the end cap on the spindle can be clearly seen in the second picture of this ebay ad.
Not affiliated with the ad.

Harold-not-the-barrel -
The ET-2 is another very interesting tone arm though.

Harold-not-the-barrel - my thoughts exactly over 10 years ago, and still today.
Welcome to the thread. Is there a story behind your moniker ?
Cheers Chris

Dave/Frogman -
Interesting your comments on going back to the aluminium arm with MM's.
With my aluminium arm I removed the heat shrink and internal foam. This yielded a lighter sound, but cleaner, clearer and less smear with both high and low compliance cartridges -Shure V15Vmr/Denon 103/Carnegie/Koetsu Black.

I also removed the soft teflon from the headshell and epoxied in a piece of carbon fiber. If you dont mind butchering your arm tube a little all you do is prise open the end, the teflon will pull straight out if you can get a good grip on it with some long nose pliers. Then just cut and insert the carbon fiber with epoxy and clamp the headshell up in a vice.

In my view with the low compliance cartridges tweaking the spring counterweight set up is plenty sufficient to get the optimum without having to add mass to the arm tube. I had no tracking problems with low compliance cartirdges in my lightened aluminium armtube. Follow the instructions on counterweight position, ie low mass further out and tuning.

When you go to 2 or 3 springs you are increasing the mechanical coupling of the mass of the counterweight and the cartridge sees more horizontal mass. I still prefer decoupling the spring by loosening the end cap and using teflon wedges to dampen the swinging counterweight motion even with low compliance cartridges.

Frogman you reported hearing more bass notes when you loosened the end cap off. Any update on this ?

Dlcockrum PS: I also have a nice stable of MMs: Empire 4000D/III, Signet TK-7LCa, Sonus Gold Blue, Micro Acoustics 530mp and 2002e, Astatic MF200, ADC XLM II Improved, and Shure V15 Type III MR. I read that some of you have liked the Empire with the ET Two. Is that still your opinion? What about the others?

A really nice set of cartridges Dave. You will want to hear them all over again with the HP manifold.

When you are up and running with it let me know if you would also like to experience the "420str". I can loan it to you for a few months.

For everyone on this thread.
I am very glad that Banquo363 decided to chime in here.
You see it was Banquo's personal 420str that he donated.... Bruce received, listened to and provided his review of here...
I am just the holder of it for the moment.

Cheers

Hello Harold, I hope some day to compare an ET to my Trans-Fi-- maybe when I find space to set up the VPI TNT and Kenwood L-07D side by side. Squeezing two linear arms onto one turntable wouldn't leave space for an LP...

Thank you, sir Chris
Nice to meet you. I very much appreciate your love and affection/opinions about linear air bearing trackers as general but I have no idea nor experience of ET-2, and especially your intelligence for having got one of the most exotic and mightiest TTs, the Platine.
Its magnetic field levitation/non-mechanical bearing must something like drive a good old Citroen. I fell for the BX more than 20 years ago and it can be taken away only over my dead body.
And me ? I´m just a lawnlower. And part of the GENESIS mythology I´m afraid. But I´m not like Harold the Barrel, that quite peculiar yet nice fellow from early days still going strong. And I appreciate him greatly as well. You see, my favorite song is "Harold the Barrel" from 1971.
Excuse me my ignorance about these fascinating things going on at A´gon lately but I´ve been busy with my own rather unorthodox experiments. In fact, I need to do a couple of final adjustments on my TT project right now.
Funny thing is, when I turn my back to A´gon for a few months at least one person has taken a giant leap in TTs... Well, you can´t stop Evolution can you.
Good day to you.

Harold

Dave, What a nice surprice as I had no idea what you have been doing after your Trans-Fi wand mods. I was wondering why´s the sudden silence though. Meanwhile I have been doing my own TT project... and watching music videos on YouTube. Rare unseen videos though but a bloody waste of time.
Anyway, congrats for your fantastic vintage DD TT, it must be very special. Seems to be slightly better than your VPI.
Hmm, it may be quite boring to play only 45´s with 2 linear trackers on the modded TNT. But I´m sure you will find a solution soon.
The ET-2 and the Trans-Fi tracker on a super deck ! Finally something really interesting at A´gon, Evolution gaining speed.
We will observe your progress. Thanks in advance.

and it can be taken away only over my dead body.

Hi Harold - the last time I heard the words sir I was working :^(
You are a gentleman sir. The stark reality of it for me is that I am a middle aged runner; and whenever I get a muscle pull, strain or just have pain, its taking longer and longer to recover. As I come to grips with my own mortality every day, I gain more and more respect for all those things around us that have passed the test of time and will still be around when I am not. Now as long as we are making clothes with thread, this Platine will provide beautiful music with no bearing to wear for someone. Likewise the ET2 if you feed it good air. The Transfi looks like an interesting design - unfortunately my personal guard comes down a 1/2 hour into the music and I become a bit of a klutz - with its permanent spot over the platter I fear for my lp and cartridge. The ET2 is pretty much klutz proof' although I did behead an XV1 once that was attached to an ET2; but it was on an armpod 15 feet way from the table. Still gives me the shakes thinking about it. thank you again Axel for bringing it back to life. If I didnt have many years of schooling to still pay for, of all the newer tonearms I have seen the Schoreder Linear Tracker looks really interesting to me.

You see, my favorite song is "Harold the Barrel" from 1971.

So cool. Without thinking I used my initials and some random numbers for my moniker - they now follow me through Audiogon eternity. I was 8 in 1971 and am a Genesis fan and the other British super groups having grown up with them, their lps and concerts. They made a huge impact in Canada and myself. Springsteen also ranks very high - this is just as much to me about the meaning of the words in the songs having the capability to stir the blood in you, as the music itself. I listened to Devils and Dust last night.

Knowing the story your moniker now ranks in my personal top four along with Swampwalker, Frogman and Vegasears - the last one doesn't need a story :^)

Cheers Chris

A couple more opportunities for ET2's.

One of the earliest ET2's available here.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=380777927186&ssPageName=ADME:B:SS:CA:1120

How do I know this ? Well it has no label / lettering on the manifold.
At first I thought it could be a fake? But then I thought who in the world could make a copy of this tonearm.

besides - Bruce confirmed to me the first ones that went out had no lettering.... :^)

The second one.

http://www.ebay.com/itm/Systemdek-IV-e-Turntable-with-Eminent-Technology-ET-2-Tonearm-and-Ortofon-HMC-30-/161159019251?ssPageName=ADME:B:SS:CA:1120

In one of the ad pics can be seen a homemade pvc surge tank.

Not affiliated with either of these ads.

Cheers

Dover, by loosening the screw the bass range gained clarity and speed. The bass is not necessarily stronger, but instead of some bass notes sounding simply like amorphous low frequency energy there is air around the notes, much better pitch recognition, and the sense of a low frequency "floor" in the music wether there is actual bass in the music or not. Of course, this was after experimenting to find just the right amount of loosening of the screw. In my setup what worked best is to loosen it completely and then tighten it so the I beam spring sees the slightest amount of "grab". Thanks again for the suggestion.

Hi Richard

regarding the damping trough location.
Are you still using your trough ahead of the manifold on your custom ET2 ?
My thoughts have changed on this.
The trough paddle is attached to end bearing cap on the stock ET2 and ET2.5.
The cap also holds the I Beam => which holds the ET2, 2.5 family jewels (lead weights and spring/s)
That end cap is therefore the common joiner for all of them.
We change resonances by using 1-3 springs and lead weight positioning,
My thinking is it therefore makes sense to have the trough paddle attached to the end bearing cap as designed.

your thoughts ...

others ?

Chris.

Hmmm. Haven't put any thought into the trough location for literally years.
I put my design trough at the wand end to reduce any shake rattle and roll of the wand itself and by extension the cartridge. Since the key to performance of the trough is to better keep the cartridge body still, it seems to be the place to position it. We have the minimum number of joints between the paddle and the cartridge, so this should be the most efficacious place, aside from putting the paddle on the headshell like Townsend did. I was just not prepared to deal with the hassle of this approach.
My arm would need a bit of engineering to position the trough at the CW end. Difficult but not impossible.

****My thinking is it therefore makes sense to have the trough paddle attached to the end bearing cap as designed.****

Chris, interesting consideration, but I am not so sure that is always the "best" location. I use the trough as intended out of convenience, but have always been intrigued by the Townshend approach of silicone damping at the headshell. Additionally, since "We change resonances by using 1-3 springs and lead weight positioning", is it not possible that is precisely why damping closer to the headshell makes sense? IOW, if we optimize resonance characteristics at the rear bearing cap, introducing damping at that point would then change that resonance "balance" to the extent that, for instance, a different spring might perform better with a given cartridge.

Our sound systems are still so imperfect that, wether we like to admit it or not, we use resonance "control" as tone controls at least to some degree. Seems to me that in an LP playback "system" what we hear as sound improvements or degradations when manipulating resonances are the result of how those resonances affect the actual performance of a cartridge/tonearm system in absolute terms not just in the subjective sense of, for instance, preferring the brightness through a particular frequency band that particular resonances may introduce. To my way of thinking it is easy to understand how certain resonances may affect the actual working of a cartridge's suspension and motor given the very low level at which the mechanical to electrical conversion takes place. On the other hand resonances that occur within, say, a turntable's plinth will affect perceived frequency balance but, seems to me, are unlikely to affect the actual mechanical "performance" of the turntable. However, those same resonances will travel to the cartridge and may affect the performance of the cartridge, so it may make sense to damp as close as possible to the cartridge. Lastly, the "shock absorber" benefit of fluid damping in stabilizing the arms movement will be there regardless of the location.

Just some ruminations possibly the result of too much L-tryptophan :-)
Hope everyone had a Happy Thanksgiving day!

Richard and Frogman thanks for the comments.

BT in the damping trough manual

You can see visually small ripples on the surface of an LP as it is turning. These continuously excite the tonearm resonance.

I am firmly in the camp of regardless what your vinyl playback system is - it is but a slave to the actual record.
I am also a hobbyist and not a manufacturer, dealer, distributor of analog products and or services.

imo - those that set the standards for records many years ago - never imagined $5000 cartridges, $5000 tonearms and $30,000 tables of today. If they did they would have come up with better standards for the records.
Frogman - as far as tone controls go I agree 100 per cent. We know when they make a record they boost the highs to drown out the cutter noise. And reduce the lows so the grooves are smaller (to fit 20 mins of music) and to keep the stylus from flying out of the groove when we play a record. We then use our cartridge and equalizer (also called a preamp/phono stage) to re-equalize levels to where we can hear it all. So to those audiophile purists that balk at equalizers - your phono stage just happens to be one. If you play vinyl you use one.

possibly the result of too much L-tryptophan :-)

To Frogman and others possibly suffering from Tryptophan may I recommend some music.
In digital form now, originated from an analog master tape.
The sampler tracks are not downloadable (yet) but can be enjoyed with either headphones hooked to your laptop or a line feed from laptop's headphone jack going to your preamp.

http://ultraanaloguerecordings.com/wpsite/sample-tracks/

I am not affiliated with the site but am a customer of their tapes.
Cheers

Thanks for the links, Chris. Very nice! Great to hear the Gliere; love that piece. I couldn't find artist info on the site. Is it there?

Hi guys, while you all are on this topic, I'd like to know if any of you have experience with the Jun-Air 16-25 compressor? I've had one waiting in the wings for a long time and it has one issue. It has the option/with a tank that captures excess oil/moisture. When it reaches the maximum pressure setting, it immediately starts expelling air, then at the appropriate low pressure setting, starts the process all over again. I feel like it's a simple fix if the solution can be identified. A stuck valve maybe? Any help will be verymuch appreciated.

Hi Slaw
maybe this helps maybe not.
Anyway - I have a Campbell Hausfeld compressor that I use with some air tools.
Last winter it experienced the same symptom you described from the tube going from the tank to the pressure gauge.
In my case it was the brass insert and delrin sleeve had worn out.
Not until it was to max pressure did it start expelling the air.
I brought the worn brass sleeve to home depot and I picked up a new one.
The lip on the brass sleeve had worn out down to almost nothing. this fixed the problem for a couple dollars.
good luck with yours. there are a couple guys with Jun-Air's here hopefully they chime in.

Hi Frogman
Glad you liked some of that music.
The artist's liner notes appear to be listed under the site's store tab. Looks like Gliere is hidden under the first one.

Jeff Beecher - Bass, Rachel Mercer - Cello, Vanessa Lee - Piano

Cheers

Ct0517

That sounds exactly what I'm experiencing with my Timeter!

The solution is: a local/or alternative for my Jun-Air.

What would these companies do without our issues?!

Thanks!

Wait!, I missed something. Do you mean to tell us all, they have Home Depots in Canada???

I just installed a Jun Air 6-25 today and find it runs for 2 1/2 minutes and then shuts off for 8. Not bad.
Tim

11-28-13: Richardkrebs
Since the key to performance of the trough is to better keep the cartridge body still, it seems to be the place to position it.

This seemingly innocuous statement requires careful examination as it continues the flawed thinking espoused earlier in this thread.
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.

Furthermore if the record is not perfectly centered, even by 0.01mm, then the cartridge is required to move in and out from the center approximately 660 times for a standard 33rpm record at Industry Standard or 0dB (20 minutes of music). This means that the arm will reverse direction 1320 times within approximately 20 minutes of music. (Is anyone here still of the view that adding lead mass to an ET2 that is reversing direction 1320 times per side of a record is a good idea?)

There are two goals which are in conflict with each other -
1. To ensure that the cartridge maintains a constant relationship with the groove the cartridge will be constantly moving to align itself with the groove.
2. To ensure that the recovery of as much information as possible which would suggest keeping the cartridge as still as possible.

On the one hand we want the cartridge to maintain a position that at all times it aligns the cantilever pivot point to the center of the groove. In order to achieve this, the cartridge must be able to move laterally freely and unimpeded whilst playing.

Any addition of mass or "apparent" mass by adding lead, stiffening the counterweight spring or adding fluid damping will increase the inertia and will reduce the ability of the cartridge to maintain the correct alignment with the groove instantaneously. The increased inertia will introduce lag to the response time of the cartridge tracing the groove and increase cantilever flex and distortion. Some may not hear this effect, but it is there and is readily apparent in a resolving system with good fundamental timing.

If you want to hear the concept proposed by Richardkrebs that the cartridge should remain still here is a link to the Transcriptors Transcriber. This turntable has a fixed arm which tracks linearly by holding the cartridge still while moving the platter underneath.
http://www.youtube.com/watch?v=IQ_r0Vk9Ct8
Have a listen. This set up has more WOW (as in pitch variation) than a wind up gramophone on its last legs. This is the sound you will end up with if you add enough lead, fluid damping and/or remove the counterweight spring as has been suggested.

As Frogman has confirmed with his experiments - when he decouples the spring and lowers the apparent mass, he gets a quicker and more tuneful bass response. Less weighty but better timing.

The use of fluid damping may ameliorate a resonance issue with some particular arm/cartridge combinations, but it comes at the cost of compromising the ability of the cartridge to follow the groove by increasing the resistance to tangential movement - it slugs the sound. A better solution is to ensure that arm/cartridge resonances are minimised such that fluid damping is not required.

I would also point out, since someone mentioned the Townsend Rock, I sold several of these when I was an importer/retailer in the 80’s. The use of fluid damping in this TT killed the sound so much, that cartridge differences were nullified. For example, one customer could not hear the difference between a Madrigal Carnegie and a Koetsu Red. I also ran an ET2 on the Townsend Rock for a while, with a Shure V15Vmr and can assure you the sound was much improved in speed, timing, articulation and transparency without fluid damping. Having dealt with Max Townshend directly, I should point out that Max’s reference cartridge, at the time he designed the Rock and the fluid damping mechanism, was the London Decca Gold cartridge, a poorly constructed cartridge with no cantilever and notorious for it’s poor tracking ability. It was in this context that he came up with the trough design.

Slaw, sounds like your Jun-air's moisture reservoir doubles as a pressure check valve. Seems to me the answer is to keep the pressure at just below "maximum". My homemade surge tank uses a check valve that I cannibalized from the Airtech (with Wisa pump) tank that exploded due to the Medo's higher pressure. That was in spite of the presence of said check valve! Be careful and make sure your tank can handle the pressure.

H F Dover.
Still....relative to the groove.

Everyone else understood what I meant.

Hi Dover,

It would seem to me that the constant corrective motion of the arm to compensate for LP production imperfections, either lateral or vertical (warps), would involve some degree of "overshoot" and, thus, generate some stylus/groove misalignment due to inertia and that a properly implemented damping system would reduce this overshoot while having minimal impact on the initial transient response, ie using a minimal amount of the damping fluid such that the paddle only skims the fluid's surface (per Frogman).

I would not argue that the use of damping is a sonic tradeoff in practice and would not be desirable in a world of perfect LPs and ultra-stable resonance-free cartridges, but perhaps it is a desirable solution in our real world of neither?

Dave

Dlcockrum

Precisely