Hi Mark
Welcome to the thread.
Yes a few NOS 420 str do exist. Many of the folks on the MM thread that Frogman referenced, own 20+ cartridges and are on a bit of a roller coaster ride with them. In order to purchase more they need to sell others. I agree also with Frogman to put a wanted post on the MM thread. Somebody that is ready to part with one will respond with a NOS or slightly used one.
My first ET2 came on a VPI HW19 IV and the original pump had a weak diaphragm down about ½ psi. It was enough of a problem to not allow it to complete the last track of lps. That plus the ET2 had been tightened up to much. I took the arm apart and let the parts go to their natural shape. Then I reassembled it using firm but not really tight pressure. The pump – well that area became a bit of slippery slope for me. I went through multiple upgrades, each time the music became bigger and sweeter.
I was reading recently on AS’s site that an ET2 owner has removed all of the mounting / adjusting hardware and linkages, and bolted the manifold directly to the armboard of his plinth.
Cheers Chris |
Hi Frogman,
Thanks so much for the advice on finding a 420, as well as the tip on stabilizing the plinth suspension on the table.
My ET2 is basically the way it came from the factory, with no tweaks or modifications performed. I look forward to applying some of the suggestions in the thread and will definitely keep everyone updated.
Regards,
Mark |
Chris,
Thanks for the response. I'll definitely follow yours and Frogman's advice on the 420 search.
My ET2 still has the original Takatsuki pump, and while I have not noted any problems with the pump, I plan on going through the arm completely once I have located a new cartridge. I have a feeling that with my system, any changes in the cartridge/tonearm setup will be noticeable...should be a fun process.
Regards,
Mark |
Recently acquired an Acutex 420STR from another member and just finished the install on my system. Initial tracking force 1.5g, VTA around zero (hard to eyeball to be sure...suggestions from others certainly appreciated!).
The 420 replaced a Grado Ref Platinum. Had to remove a thin lead c'weight, due to the lighter weight of the 420. Counterweight slide is a little past 4 on the scale. My first test track was "Mas que nada", Sergio Mendez & Brasil '66. The sibilance on this track is usually a good indicator to me of cart compliance and treble performance. The cart picked everything up without a problem. My initial impression is that I will be experiencing a lot more detail than the Grado was able to provide.
I'll continue to update the group as I run through my usual evaluation tracks and the cart settles in. Thanks to Frogman, Chris and Nandric for their advise and assistance in making this upgrade!
Regards,
Mark |
Hi Mark – that is excellent news. Was there any difficulty connecting your cartridge leads to the 420str ? The back of the cartridge is angled up - a tight fit with the ET2 armtube if longer leads are used? ...suggestions from others certainly appreciated!. Only thing I would offer up right now is to leave things as they are for a few days to establish a reference point. Then remove as much lead weight as you can to get the weights sitting past 6 on the I Beam scale. Your bass will become ...... well why don’t we let you tell us what it does for you ....... . Some previous hints are in previous pages here on the thread. I like to think of the I Beam as a Pirate Plank. Get out as far as you can on that plank without falling into the water. My I Beam with the 420 str has the base lead weight plus only one thin lead weight on it. Its past 6 on the left side and I can just see the very edge of the I Beam on the right side. Looking forward to hearing about your progress... Cheers Chris |
Chris, hi there,
Thats exactly where I ended up with the Shure V15 - 1 lead weight far far out.
I think with the electrodampening of the lateral tube motion and decoupling of the beam in place, even low compliance cartridges benefit from least weight furtherest out approach. |
Glad it worked out, Mark. I second Chris' comments and would also suggest that you check the spring on your I-beam to see if you have a single or double spring. I have found the 420 to perform best with a double spring I-beam; the difference is not subtle.
Keep us posted. |
Hi Dover – I have an offer for you. As the current holder of our famous “420str Celebrity”, I am willing to send it to you next, to the other side of the world - with only these conditions. 1) You are able to resurrect your unique ET2 2) Provide us with your impressions here 3) Promise to send it back to me within three months of receiving it; So that it can be prepared for the next recipient. You see Dover, the way I see it; I am not worthy to just hold onto this crackerjack box cartridge. A cartridge that looks just like it fell out of a model airplane package. Especially with talks of $10 – 15k cartridges on the MM thread, this cartridge which demands nothing more than perfect tracing, needs to be experienced by as many as possible. I figure what better way than sending it to New Zealand. Lets call it our threads version of the blue or red pill. Do you think you are ready for the Red Pill? Offer stands..... |
Thanks Chris - I would take up your offer, but alas I cant get the ET back yet. I am having to play the long game on this one. I would be happy to throw it on the Fidelity Research FR64S/Dynavector DV501/Naim Aro if you are interested. |
No idea how Dover and I got involved in this 'wrong thread'. That is to say with the wrong kind of tonearm (grin). Anyway this seems somehow connected with the Acutex 420. BTW also an 'wrong cart'. I am glad to have sold all of them.
Chris , sorry for you but Dover got a much better proposition(s) from me. The first was to compare Glanz 31 l with the 31 E and the second to see what his Andreoli MC pre can do with my Sony XL 44 l (Raul was very impressed with this cart). No conditions of any kind are involved. This btw is 'not done' among friends (grin).
Regards, |
****No idea how Dover and I got involved in this 'wrong thread'****
Perhaps because somewhere in the subconscious there is a pequena voice saying that no one person(a) has all the answers in this wild hobby. And, that in spite of hero worship, the subconscious usually knows where the truth lies :-)
Viva la verdad! |
Dear Frogman, Those who hear such voices should, I think,
consult a shrink (LOL). I already have so much trouble with
my conscious self so I would be crazy to add the
subconscious one. Besdides I may get involved with Freud this way (grin).
Viva la musica! |
Nandric - I'm an honorary member of the ET2 club having owned one for many years since the 80's. Unfortunately in a moment of madness I gave it to a friend who bought my old Roksan TT. It will come back eventually. |
Dear Dover, I am involved because of my friend Chris who is
also a 1/4 compatriote of my. Sort of. His parents are from
Macedonia a former 1/2 'brother nation' of my but he
is born in Canada and that explains the nummerical relationship.
Nice guy but be cerefull not to mention the room acoustics
otherwise he will 'furnish' your home: with damping plates.
Regards, |
Hi Nikola – thanks for making my morning coffee interesting. We all have our sonic preferences in this hobby. I have to confess I am a bass guy. It is important to me. We all know bass will make you understand how important the room is, both from a sonics perspective as well as not irritating your wife/family, neighbors. The technique I use for bass tuning is very simple. I have Quad 57 my midrange reference in one room. Most of the music is in the midrange. The 801’s are in an adjacent room. I tune their bass until I hear everything that is coming from the Quads midrange. The above arrangement requires a larger room split into two pieces. fwiw and just my opinion - Strategic damping plates are important but a room that has allowed for bass seepage is far more important and effective for bass control at higher spl’s. This however requires a carefully developed understanding with the above mentioned wife/family and neighbors. I think there should also be a separate category for the audiogon forums called Rooms setup / Treatment or something like that. Audigon are you listening. If you can’t make your own panels, get the commercial ones now before they become truly mainstream one day and $50 panels become $500 or $5000 with high end. Sibilance can also be resolved with room tuning. We listen to our rooms. Sorry to digress.. Hi Dover et al Honestly this 420 can be a real PITA on a pivot arm. Its reputation is justified. I think only Henry and Griffiths found some nirvana with it after much tribulation on the MM thread. There could be others. This speaks volumes IMO to their determination. I have listened to it on a ET2 ET2.5 and pivot arms. Two things. One real and one not-real (virtual). First - The 420str is a real physical cartridge. You can touch it and you can feel it. You even bite into it. Here she is the 420 with her two sisters called 412 and 415 Other than their obvious color differences the other differences seem to be in the shoes the sisters are wearing. I asked a question a while back on the MM thread because I thought – there are many cartridge “experts” here. I am not a cartridge expert. They will answer my question. No one answered the question. I can’t remember the exact words I used - something like this. "Looking at the picture how would the very different shape/design of the 420 cantilever/stylus affect the sound and setup requirements over her sisters?" Since asking that question I have heard the 412 and 420 on an ET2 – Unlike the 412 I found the 420 very linear (sic) in the bass, mid and HF’s. To me the two sisters of the 420 based on their shoes, really do look like sisters themselves – but the 420 is like the odd child, even though it is the top of the line model. Is this starting to sound a little like Cinderella yet? Now the second part. This is the part that is not real (virtual). Our hobby is full of gear. All of us piece together a bunch of gear to produce an imaginary state in our rooms. A state that we cannot really see, touch, or smell, but we can hear and feel. I have had the 420 cartridge on my FR64s and DV505. I eventually after much work got it to sound ok - good – but only HIFI good. I wasn’t able to get into the music.... . involving me, like the ET2. The presentation and soundstage of this 420 cartridge on the ET2, is like you're reading a different book, compared to the pivot arms in my room. Sometimes the shoes just fit? After some effort the shoes seemed to fit at first with the pivot arms too – but after some time blisters became evident. So personally would not bother with the 420 on a pivot arm again. Life is too short. Thank you Nikola for the inspiration in your last few posts. I have now added Cinderella to my virtual page. She joins Winnie the Pooh and Goldilocks. What a fun hobby :^) |
Hi Chris, a follow-up on a project that I mentioned a few months ago I would be attempting. I have procured a small piece of cocobolo from a musical instrument (clarinet) maker friend, from which I plan on constructing (with his help) a "mount" for my 420 to replace the flimsy plastic one that is stock. Actually, I will be using the "corpus" (in Nandric-speak) from a recently purchased 412, which I have every reason to believe is identical to the 420's; the two differing only in their stylus assemblies. My hope is that a far more rigid platform, with better resonance characteristics, will improve the performance of the 420. Will give updates as time allows. |
Hi Frogman – looking forward to hearing more about the project, and hopefully one day sending you my 412 “corpus” to do the transformation. :^)
My current 420 has pin sized blue tack dots making it a little more rigid. It helped
My next step was to crazy glue it like my Empire 4000 diii Gold.
Glad you reminded us. I will hold off.
Note: our travelling 420 has been crazy glued already by the previous owner that donated it. Not sure if he knew the role it would end up in. He is not an ET2 owner – yet. Hope he chimes in here one day anyway. |
Chris/Frogman,
Changed the c'weight to get it out to 6...although I have both I-beams, I have always used the double spring, as I felt it sounded better.
No problems with the lead wires...tucked the extra wire into the arm tube, and it fit OK...close, though. If you have long lead clips, forget it!
This cart is quiet!!! Now sounds very linear, with some added emphasis in treble, which is good, as my 300b setup tends to sound a little dark.
Listened to "Famous Blue Raincoat" yesterday, along with a 45 version of "Rumours"...the additional detail really brings a smile to my face.
Will contine to update you as the cart breaks in...
Regards, Mark |
Thanks for the update, Mark. Keep us up to date. |
If you have long lead clips, forget it! Now sounds very linear, with some added emphasis in treble Exactly what I found Mark. The added emphasis with me decreased with break in. But again it was very linear meaning it was noticeable over a period of time not overnight. A general question to all. Can a cartridge with known emphasis in treble, if placed at an offset in the groove, cause this “emphasis in treble” to sound like harshness, sibilance, distortion ? |
Offset – Just to be clear in my previous post when I say offset - I mean anything that is not a perfect zenith IMO as an end user – since vinyl records are not perfect (both in their physical attributes and the way the masters were cut) – no tonearm out there is able to come to a perfect zenith. Anyone disagree with this ? Some however 1) allow you to come closer to Zenith in setup, and 2) keep it there during play. In this hobby I personally want a tonearm that can do both 1 and 2. Fwiw - I have had two 420’s on two ET2’s simultaneously. I was able to tell by listening which one IMO came closer. This forced me to fine tune one of them. |
Antiskating and Frequency Modulation Distortion of Different Tonearm Geometric Hi Guys (gals?) There has been a few different threads on the Gon recently about turntables maintaining their speed - Speed Stability. The effect of stylus drag with turntable speed is always mentioned and acknowledged. I continue to go back to Bruce Thigpens ET2 tonearm manual, and find information that I had either overlooked or forgotten about. IMO - for anyone in this hobby this manual contains important data. Here is BT's information on this subject, the forces involved and some real measurements. The Et2 manual on page 51 says that an LP record contains approximately 40% vertical energy and 60% lateral energy. These are significant and different forces at play. BT did testing of these forces as they applied to different tonearms. The manual section that summarizes these findings follows. Taken from “the Eminent Technology ET2 Tonearm Manual - Pages 46 and 47”. Disclaimer - This is public information and is available online at the Eminent Technology website under support/manuals/ET2 owners manual. Antiskating and Frequency Modulation Distortion of Different Tonearm Geometric
Pivoted tonearms are designed so that the head shell holds the cartridge at an “offset angle” with respect to an imaginary line drawn through the tonearm pivot to the stylus tip. The arc traced by the stylus tip extends past the record center and is defined as “overhang”.
This design approach minimizes tracking error. There have been many articles written about the geometry of this design approach. Pivoted arms create several side effects which reduce phono cartridge performance. The first is a skating force which results from two different parts of pivoted arm design.
There is a force component (vector) that is directed toward the center of the record. It results from the stylus drag force vector not falling in line with the pivot point of the arm. This force pulls the tonearm inward and the stylus can be observed as bending outward. This force and the resulting bending can be demonstrated by connecting a rubber band to a pivoted arm around the cartridge body and pulling it straight (away) from the tonearm. Note: the motion of the tonearm is inward and results in bending of the rubber band (cantilever).
If you corrected these forces with an anti-skating mechanism such that the stylus did not bend (you can not really do this because the frictional force and resultant bending varies with groove modulation, stylus shape, tracking force, etc...) there still exists another component of skating.
This second skating force results because of overhang. There are frictional force vectors that result which are not directly ahead of the stylus. The surface of the record is not really moving straight ahead with respect to the stylus tip. As a result, there are force components directed ahead and toward the center of the record. The magnitude of the inward force depends upon the degree of overhang.
This means that any given cartridge works against lower horizontal forces in the Model Two tonearm (.1 gram or less) compared to a conventional arm (.2 grams/gram vtf). These figures apply if you use records that are not severely out of round. If you like to play severely eccentric records, ones with runout of greater than 1/8”, then we suggest you use a low mass pivoted arm.
For vertical forces while tracking warps, the cartridge suspension system must work against the tonearms moment of inertia about its vertical axis of rotation. For the Model Two, these forces will be similar to those of a conventional tonearm which has low to medium effective mass (10 grams). Fwiw - As an owner of both pivot and straight line tonearms I am aware that stylus drag differences differ with each. I never did take any measurements. It is now possible with software, a test disc and your Android or Iphone to measure things like turntable speeds and tonearm resonances, as discussed in this thread. See the post from Halcro |
Fellow ET-2 owners,
Surplus Center has a quantity of Medo AC0110 pumps available for $19.99 each. I bought one the other day to try out and found that it delivered a steady 6psi to my arm and was fairly quiet compared to my stock Takatsuki pump. The 30 minute duty cycle is a bit troubling, but found that after 30 minutes the pump didn't get too hot. I got a second pump and plan to hook them up to a surge tank and see what happens...Here's the link: https://www.surpluscenter.com/item.asp?item=4-1894&catname=
I would appreciate others thoughts on using this particular pump.
Regards,
Mark |
Hi Mark Wow - thats a great price on these pumps. Here is a direct link to your site. Medo PumpI paid $60 or something like that for each of the two I had. Placing a really small fan next to the pump will alleviate any worries of overheating. Years ago I accidentally left mine on all weekend to return with no problems. Cheers Chris |
I appreciated Chris's song list earlier, I also agree with a few others there. I've come across an interesting item that I'm currently using. I plan on integrating it into upcoming projects.
www.DragonPlate.com. I'm using the PP core plate.
I can only state the remarkable sonic upgrade it has made under my EAR phono. You can decide for yourself.
|
Saubmgc: I had a Medo AC120 (I believe) and while it performed well beyond it's stature, it did run hot. Still no trouble in the long run. It's been gone for quite a while. I'm running 18.5 psi with my current compressor. |
Nandric:
I'm an interested party in regards to a second Acutex 420STR. I love mine! If it wasn't for Chris I wouldn't have mine.
I'm enjoying my system more than ever now! No turning back. |
Slaw – My first 420 str, I tried out as I did the other MM’s the last year or two on my pivot arms first as they have removeable headshells and make it easy; and another big reason I hesitated putting it on the ET2, as Mark has already pointed out; the angle of the cartridge pins can be a real PITA on the ET2 armtube if your wire leads are long. Here she is on the pivot arm – well sort of a hybrid arm in this case – DV505. http://cgim.audiogon.com/i/vs/i/f/1322856939.jpgI got the 420 to sound good, but it didn’t better a couple other MM cartridges I already owned. It was not until I read Frogman’s post about it on the ET2, that I removed a cartridge that was on it, put the 420str on the ET2 and it was like – holy crappola. BTW - I am not sure if Nandric is coming back here although I hope he does. You have been away for a while. I think it has to do with being on the "wrong thread" and being asked to consider taking a Red Pill. |
Dear Chris& Slaw, I sold my last 420 to Mark but am still
'loaded' with other ,uh, interesting MM carts. If you
promise not to tell the guys by the MM thread I will
confess to prefer the MC kind. I spend a fortune on those
lately: Kiseki Silver Spot, Shiraz, Benz LP S and Magic
Diamond. The last mentioned really deserves the adjective
'magical'. It is of course not done to try to sell whatever
via our forum but it is also very rewarding if one can help
an co-memeber. Even more so if the person in casu is a
friend of my friend Chris. I hope my address is still by the member list.
Regards, |
Nandric - do you have a ranking for your MC's at this stage. Am very interested to hear what you think of the Magic Diamond. The Kiseki Silver Spot I know well so if you do a comparison to that then I can work it out from there. |
Dear Dover, I hope you realize that we are again in the wrong thread? Except of course if we intend to hide our preference for the MC carts from our MM 'comrades'. My
provisional ranking is: 1. Magic Diamond;2. Miyabi Standard (aka Krell KC100);3. Benz LP S 4. Kiseki 'Silver Spot'.
First of all I am informed by an owner that the Magic with a ruby cantilever really exists. So the one we both have seen on ebay.com is not a 'fake'. Second I am not sure if my Kiseki is 'Silver'- or 'Gold spot'. My has 5 screw holes on each side while according to some this should be the 'Gold one'. Anyway the cart is very fast and very dynamic, similar in this regard with the Miyabi. The Magic is, uh, 'magical'. Probable too good for some Balkanes. I would say really 'neutral' and refined. But only the Miyabi is in my main system at present .With Basis Exclusive, Kuzma S.R. the Reed 2 A, etc. The rest I tested in my second system with FR-64S/ SP 10 Mk 2 and Jasmine LP2. Hence my 'provisional' ranking.
Regards, |
02-04-13: Nandric
Dear Dover, I hope you realize that we are again in the wrong thread? Dear Nandric (Nikola) My mother used to say to me. “That is wrong son...don't do that” “Don’t do that son, it is bad for you” “If you keep doing that son, your xxxx will fall off” The funny thing is, I remember that the more she said things like this, the more I ended up wanting to do those things. Back to normal programming. Here is something alien but valuable I think. Alien Screws Just received in the mail the brass screw set. Seems like a good price for the quality. Not affiliated with the site. As a tweak for ET2 owners, if your current cartridge set up does not allow you to get to end of the I Beam with the lead weights putting the next size screw / bolt on may be all that is needed to get there. I keep losing the things myself. Cheers |
Hi Guys,
Sorry I've been absent from the thread, but had to travel last week on biz...
Slaw, thanks for the additional input. I purchased a second pump, just to be sure...
Again, thanks to Nikola for selling me his last 420...I am indeed enjoying it very much!
Finally, there have been a couple of NOS 412's on eBay this week...don't know if they are worthy of consideration.
Best regards,
Mark |
Dear Chris, I don't believe that your amount of TT's, tonearms, carts and more in particular speakers can be explained with your mom's upbringing methods. But I must
confess that my both sons whose education cost me a fortune still ask: 'do I got THIS from you or mom?' BTW my youngest (36) never say 'Hi dad' or something similar
but instead : 'any new tonearm dad?'
I think that Dover and I like gossip and that is why we occasionaly participate in 'your thread'(grin).
Regards, |
Sorry Guys, my bad...
I originally stated that there were a couple of Acutex 412's for sale on eBay, but in reality there is one 412 and one 415. I would copy in links, but am not in a position to do so.
I would be interested in other's opinions on these two cartridges in the ET2...
Regards,
Mark |
Hi Mark – from the specs in the manual which shows all three the 415 is closest to the 420. I have the 412 not the 415. I found it wasn't as linear as the 420 (hf, mid, lf). Frogman is using a 412 to make a new body for his 420 ? Maybe he will chime in if he sees this. I recommend a quick post on the MM thread asking for a 420 and for someone to pm you. Pretty sure somebody will respond to you. I paid around 70 euros for the 412 from what I recall. Cheers Chris |
Hi Chris,
Thanks for the response. I'm not in the market right now, as I got a 420 from Nandric, but wanted to know for future reference. Maybe if the price is right on the 415, I might try it out for comparison purposes...
Regards,
Mark |
Chris is exactly right, the 412 is not a as linear as the 420; a perfect description. As far as I know, the body ("corpus", thank you Nandric) of the two are identical. The difference between the two is in the stylus assembly. If you don't plan on doing a lot of cartridge swapping, and given how easy it is to swap stylus assemblies, it might be of value to you to have a 412 stylus assembly for casual listening and thus save the stylus life of your 420 stylus assembly. |
The designer/producer of the Terminator tonearm bought one
of my 420 and also 415, 412 and M 312 STR by the 'pizza guy'
in Italy. He was impressed by 420 and M 312 and not
so much by the other two. The 312 is still available on the
Italian ebay ( testina giradichi) for 45 euro + postage (12euro?).
I know of course that the Terminator is no match for the
ET-2 but both are linear so why not try? |
Chris: Regarding your recent reply about the 420str... I'm really not sure what I'm suppose to take from this. Frankly, I love the cart/the sound w/my system. I was the one that initially remarked here or to you privately that the cart pins/angle would be an issue. I'm not one that really wants to try cart after cart. when I find one that sounds this good, I'm good. ( I have thought of a way to remedy my much earlier cart/pin/overhang issue when I decide to take the time). I'm just having too much fun listening and frankly don't want to take the time to change right now. Too much good music, too little time! Yes, it's true! |
Nandric -I know of course that the Terminator is no match for the ET-2 but both are linear so why not try? Hi Nandric (Nikola) Never heard the Terminator yet alone on the same table as an ET2. Feel free to share your impressions. There are Terminator owners here as you know. I have found personally, and you can confirm this by looking at individual setups. We SL Tonearm owners seem to share one thing in common- a straight line – anywhere on the LP. From there we are all very individualistic. Not one set up is the same. Cheers Chris |
Slaw - Mark asked for an opinion - I gave one. I am done with cartridges myself. Unfortunately I keep misplacing/losing the damn screws in the carpet. I hear tinkle tinkle sometimes when I vacuum. Hence my post about the screws. Have a nice day. I have to go shovel snow. Haven't seen anything like this in 10 years.
Cheers Chris |
Nandric, Absent direct experience with Terminator, your remark would seem to be a good example of what psychologists call the false consensus effect. |
Dear Dgarretson,If you called my 'assumption' the false 'authority consensus' I would agree. We are supposed to share information we have but this does not mean that we
checked everything in the sense of the truth value. I thought that the opinion of the mentioned desiger may be relevant info but my primary intention was to mention this
cheap and available alternative (M 312) for the 420 which is obviously difficult to get. My 'horses' are elswhere btw.
Regards, |
It seems we may be getting into symantics,?
Read between the lines......
My message has been, 'focus on the music'. Why do we need to discuss varionses between this or that component... at this stage... the most important thing is the music. May be, we should be discussing how many times we seach out new music?
Myself, I'm spending $300.00 + per month on LPs!
Yeah, that sounds right?! |
Picked up two of the medo pumps and pleased to see they are 50/60Hz, so proposing to run them in parallel off a step down transformer, as our mains supply is 230v. There was a suggestion to run two pumps out of phase with each other. What should I do with the earth wires, or should I leave them unconnected?
Any other advice for using these pumps greatly appreciated.
Regards
Grant |
Hi Grant – welcome to the thread. Another New Zealander. I wish I was there right now.
With both Mark and yourself discussing Medo’s I dug out my medo ac0110 pumps from the past today and hooked them up separately and together to experiment. I remember I received them with three wires hanging. I cut off the three prong from two power cords and spliced them to make the wall plugs. So I did connect their grounds. I was only using one at the time and the other was a backup.
Separately mine both produce about 12 psi on a pressure gauge inserted within a few feet of tubing to the ET2. A real dynamo of a pump for only being a couple inches by a few inches.
When I connect them together on a T Valve PSI only goes up to about 15 psi as they are working against one another. Hopefully someone else can chime in if they are using two Medo’s. I went to the Timeter pump after the single Medo. The Medos are a linear piston design if that helps. Maybe Dover if he sees this can offer some advice as he used multiple pumps with his ET2 setup.
Cheers Chris |
Hi Chris/Grant
Yes I used 2 pumps running into a 20 litre surge tank. On the pumps I used, reversing phase & neutral at the transformer inside reversed the phase on one of the pumps. In NZ you must not reverse phase and neutral at the power cord because the mains fuse must be in the phase line. |
Hi Chris/Dover
Thanks for that information very helpful.
I have an ET2 with original low pressure manifold so I think 12 to 15 PSI if anything may be too high. The original pump did not like 50Hz, managing typically less than 4PSI.
Have filters and a pressure gauge, but not sure what a "regulator" is and locally what industry would be the best source for a suitable unit.
As the pumps are 115V, 50/60Hz I briefly considering running the two pumps in series, one "out of phase". I thought better to run them off a step-down transformer in parallel. Pumps would be housed inside a baffled box so effectively double insulated and isolated from one another, with the surge tank also housed in the same box.
For the surge tank I was going to use PVC pipe and fittings (2 - 300mm lengths of 200mm dia pipe with sealed end caps). Any advice on packing, was going to try some left over "BATTS".
Am I on the right track?
Many thanks for the advice.
Kind Regards
Grant |
You've just reminded me - I got a big improvement when I put an isolation transformer between the mains and the pumps. Much smoother sound. |
