VPI Prime Sig/Lyra Delos / Feedback ...help!


Hello all, strange one here...just picked up a VPI Prime Signature Rosewood and a Lyra Delos with about 20-40 hours on it...sounded great at low volume with my sacred Steely Dan - Aja Cisco pressing . Later that night at higher volumes I'm getting a midrange-low feedback . 

Here's my rig : 

VPI Prime Sig with Unipvot / Lyra Delos 0.6m output voltage / 1.75 tracking force

Allnic 1202 Phono Pre (variable DB boost  +22, +24 , +28, +32) 

Manley Snappers / Jumbo Shrimp Pre 

Harbeth 40.3XD 

So I A/B'd w the old turntable VPI Prime Scout / Unipivot / Hana ML 0.4 Output and all was fine 🤔 I then swapped arms moving the Hana to the Prime Sig , no feedback ....🤔

I've tried adjusting the Allnic (all 4 levels mentioned above) and get feedback with the Lyra on every setting...

The hifi business I purchased from said they had tested thoroughly and had 0 problem with it ...so I'm perplexed , this doesn't seem to be any vibration feedback , is the Lyra just not jiving with my Phonostage for some reason? 

Any help appreciated ...

 

128x128tommypenngotti

How far away is your table from your loudspeakers? Do you have any isolation device under the turntable?  Some carts are more sensitive than others to acoustic feedback.

 

 

@karl_desch 

pretty close by but not sure where I could put the TT where it's gonna make any huge difference...only sound isolation is the Prime Signature feet which are padded & fairly good acoustic feet . 

It seems from your description that the Lyra is the source of the feedback.  If you are comfortable switching cartridges, try substituting in the Hana to the new TT and see if the problem goes away.  If so that tells you that the Lyra is just a much more sensitive cartridge.  Not all bad.  If that turns out to be the case, you need to isolate the new TT.  I would try some ISO-Accoustic GIA feet or similar isolation device to resolve the problem. 

@billstevenson ya , I've already tried putting my old arm with the Hana ML on it on the new deck in same position as the feedback was happening w Lyra & it works 100% perfectly ...must be the Lyra is just SUPER sensitive...

This just in - VPI recommended a continuity test on all headshell wires with multimeter...the white wire seems intermittent...not sure that is the culprit though , I think that's a ground..

White is the left channel “hot” wire.  White (hot L), Red (hot R) so it could be an issue in the arm wiring…

No way this has anything to do with tonearm wires. And yes, white is L channel hot, if it mattered.

The Lyra cartridge is NOT prone to resonating and causing feedback problems.  It is most likely the combination of the arm/cartridge/table suspension that is unfortunately tuned to a resonant frequency that is causing the feedback.  You could try adding a small amount of weight to the headshell to see if it moves the resonance to a less sensitive frequency, or you can try tuning the table to change its resonant behavior (put it on a different platform, add weights to the plinth, etc.  

It probably makes sense to reduce the overall tendency of the platform the table is sitting on shake--if it is on a rack, can you make the rack more rigid?  If the rack is close to the wall, the best way to make it more rigid is to somehow attach it to the wall.  I did this by putting a cleat on the wall near the top of the rack and then using angle braces to attach the rack to the cleat.  This made the stand MUCH more rigid.

Tommy, you have several problems that lead to issues like this. Your turntable is not adequately isolated and Lyra cartridges do not like unipivot arms. You need an isolation platform tuned to 3 Hz or below and a gimbal pivoted arm, then the Delos will work fine. Lyra cartridges are relatively compliant and that arm is also too heavy for it. 

@mijostyn l

@larryi

Thanks for the help , however my unipivot w Hana ML never feeds back in exact same position with same isolation feet 🤷

 

VPI seems to think the tone arm white wire shorting is the culprit 

 

 

Mijostin's comments make sense.  If the arm is already too heavy (meant for a low compliance cartridge) there is nothing much that can help.  You have a basic incompatibility, and perhaps a beef with the dealer who sold you the cartridge.  It is not the fault of the cartridge--it is like putting the wrong kind of tires on a car and blaming either the car maker or the tire maker for the poor performance.

While you might not be able to cure the problems that result from this incompatibility, you might be able to reduce the feedback by changing the isolation and tuning of the table's suspension (try different platforms, different feet, try making the platform the table is sitting on more rigid, etc. If your unipivot has provisions for damping its motion you can change the amount of damping.  

@larryi 

yeah I get it, I’m gonna try moving around the table today,…

funny how VPI and also Lyra recommend this cartridge with the table and the arm I have 🤔

 

 

"funny how VPI and also Lyra recommend this cartridge with the table and the arm I have"

File this under "on paper it's  not supposed to work, but it might" category.

I've heard more than a few Lyra on VPI's, and they all seemed to sound good.

Tried  a Delos on my Classic and it was great. Sits on cheap stand supported by 100 year old wood floor.

The ol' YMMV strikes again.

 

 

"guess it wouldn't hurt to pick up the Fatboy Gimbal & A/B.."

I thought  the gimbal was standard  on Prime Signature? Guess not.

My Lyra experiences were with the low tech uni pivot. 

Good luck finding what the culprit is.

@tommypenngotti, If you have sound in both channels nothing is shorting. Lyra absolutely does not like that arm. They specifically specify "a pivoted arm with rigid bearings or linear tracking arm." That does not include a unipivot for very good reason. They are unstable. You are having more trouble with the Lyra which is a more compliant and more sensitive device than the Hana. It is a great choice just not for that arm and I do not know everybody else's motives, but I do not have one. There are certain aspects to tonearm design that can not be violated. There are plenty of people in the audio business that are not rocket scientists and many have motives that are probably not in sync with yours. 

Yes! the Fatboy Gimbal is way better. Go for it!

Post removed 

New theory : 

the Lyra cart doesn’t like my phonostage . Allnic 1202 ohms aren’t jiving and it’s making the Delos work too hard and I get low end rumble at higher volume . The Allnic does have variable gain boost ..I’ve tried them all and same result . 
 

I seriously doubt it’s the position of turntable or the arm because pretty much same arm on same deck with lower gain Hana ML cart works fine . 
 

 

Ralph@atmasphere or someone technical needs to chime on  this one.

Curious to read their take.

I have heard a number of uni-pivot arms, including two that I owned (Graham 2.2t and Basis Vector 3) and none of them suffered from any feedback issues.  These arms were used with Lyra Helikon and Titan cartridges.  If there is a feedback issue (resonance) it is either a very unfortunate combination of all of the mechanical parts of your system--the cartridge, arm, table, table support--or, a defective cartridge.  

What you are calling feedback when playing loud passages might be mis-tracking.  That mis-tracking can be a product of incorrect alignment/setup or, again, a defective cartridge.  

It is almost assuredly not an issue of incompatibility with your phono stage.  The only kind of incompatibility that would remotely sound like feedback would be an overload (too strong a signal being fed into the phono stage), but, that is not the case because you heard the same problem with different gain settings.  

My "bet" would be mis-tracking caused by a defective cartridge.

Yeah, I've fought with that on VPI tables in my "difficult room" office setup. Went though all the usual "maybe it's the cartridge / phono / etc" and tried several combinations of each. I've even used 2 different VPI tables here: Aries 3, Avenger Ref. These VPI tables and their arms do seem to pick up frequencies around 100 Hz plus/minus. The Clearaudio Innovation Compact I used prior to these didn't have any problem in these frequency ranges, but then was a nightmare in the subsonic frequencies - which are potentially dangerous to your speakers. 

If your rack / shelf / feet aren't isolating enough at these frequencies, you'll have a problem. Feet can help a little - the HW40 feet seem to mitigate it by ~ 6dB? The classic Signature feet were absolutely useless. The shelf you have the table on matters a lot. I have a Critical Mass Platinum on a Sotto Voce (very expensive) that's surprisingly ineffective at these frequencies - in fact I think it's contributing to the problem (I place more blame on the rack structure underneath). I've heard from a friend that Symposium Ultra platforms was effective for him. I think a Townshend Seismic platform would probably clean it all up, but they're awkward to use and I sold mine with the Clearaudio. 

The one really surprising finding I've made in all this - the VPI arms with 3D material pick up this feedback a LOT more readily than the older metal arms. Even unipivot vs. gimbal vs dual vs fatboy (they're all 3D material) doesn't affect thing like the actual arm material. The metal wands are simply much quieter in this frequency range! The worst wand I had was an older 3D 10" wand (shiny finish). If you have an arm+cart combo that's quieter, it's probably due to the wand, not the cart. 

One last weird finding - I noticed that even the SUT I choose, and its placement on rack, can have a big impact on feedback. I don't know if that's due to the SUT itself being microphonic, or feedback back into the arm through the cable. The Bob's Devices Sky (lightweight little boxes) gave me the worst feedback problems when positioned on top shelf next to my table, until I moved it to a lower shelf - the it quieted down. The EAR SUT (much more substantial box) has no problems on the top shelf. 

@tablejockey @mulveling @larryi @atmasphere 

so frustrating....thanks for the help ..I wanted to add that the low end rumble is basically like the bottom end is not tight & consistently ringing...even tested with acoustic guitars (no drums) still get the low end rumble..

 

So the latest is the arm was sent back to VPI for repair of the white lead...when it returns I'm going to try some better isolation ...incidentally my room is heavily treated with sound panels ,bass traps, sound absorbing curtains....

I might try the HW40 feet I have , they seem way shorter than the Prime Sig feet so not sure all will line up with motor? 

I might try the HW40 feet I have , they seem way shorter than the Prime Sig feet so not sure all will line up with motor?

@tommypenngotti Yep I had to shim it with hockey pucks as needed to line everything up. The HW40 feet will help for sure - it’s worth it rearranging for.

The issue as you describe it is extremely similar to what I’ve fought with. In fact with some of my worst configurations, it could get excited to an almost runaway level of that rumbly / hum noise (grows in level on its own, until I mute). And yeah, acoustic treatments won’t do a damn thing about it, either. Best I can tell, the problem is due wholly to structure borne energy, not acoustic.

The top shelf and its support underneath is what determines how much of this energy your table has to deal with. The VPI arms are sympathizing with the energy (less for the metal wands), and the table plinths don’t do much at all to stop it. Squishy feet like HW40 are really your last line of defense. Think if I had a rack with cross-bar support level (at least for the top shelf), and support discs positioned more toward the interior of top shelf, that would help a LOT (e.g. higher-end Critical Mass, or for a LOT less money Adona Reference racks, etc). As it stands, my Sotto Voce rack only supports its top shelf along the very front and back edges (with a few simple rubber bump feet) which I think is a big part of the problem in my case - the CMS Platinum shelf, substantial as it is, acts like a drum skin at the problem frequencies.

Here’s how I "test" a given configuration: lower the stylus in a still groove (turntable at rest!) and turn the system on / un-mute at your normal listening level. Modestly thump the top shelf near your table with a few fingers. That "drum" like feedback level tells you how bad that config is. The worse ones will be much louder per thump, with a very long-lasting ringing effect. Get a feel for what it is now so when you change configs you can meter it against that. An iPhone can record these frequencies just fine, so take videos for comparisons. However, you will need to playback with decent headphones to reproduce those frequencies.

The problem (obviously) gets exponentially worse at higher SPLs. Guys who cap out at 70 - 85 dB are going to be like like "huh? my table is dead quiet!" because they won’t ever hit that threshold to excite these resonances. I listen loud (up to mid 90 dBs continuous), and yeah in this small room with bouncy floors it’s a struggle. My main rig is in a bigger room with much more solid floors, and it was easier (also that table is on a CMS Maxxum which is much better).

Which exact VPI arms do you have, and which is the one that’s been the bigger problem? The metal arms are just much quieter at these frequencies, in my experience. Sure they might "ring" at high frequencies, but that is MUCH lower in level and easier to deal with. 

@mulveling

Great advice , you hit on 2 things that are my life ...Hockey/Drums 😃

Pucks  .....is there some better isolation thing I can stack under? Pucks seem super stiff and could transfer? But definitely HW40’s under table 👍🏻 Also the checking feedback with LP stopped is on the agenda when I get the tonearm back. I have 2 arms . The metal JMW-10 (no feedback) and the 3D printed JMW-10 that came w my Prime Sig (feedback galore)

I was thinking about trading in arm for the Fatboy Gimbal , but if it’s this same plastic resonant material I’m nervous..🤔

My hifi desk/shelf isn’t anything special, just a long cabinet that holds/displays the amps and TT.

 

Thanks!

 

I was thinking about trading in arm for the Fatboy Gimbal , but if it’s this same plastic resonant material I’m nervous..🤔

@tommypenngotti I did exactly that move last year - started with 10.5i metal (Nordost) and 10" 3D wands on an Aries 3. Super cool table, but the 3D wand was just awful in my setup, because of this feedback. Unusable. Then I swapped to 10.5i, and everything was was lovely - big surprise, given all the feedback (haha) online about how much better the 3D arm is. I’ve heard a 3DR sound great - in my buddy’s system. He listens loud as me BUT he’s on concrete slab, and it’s no problem there. It even handled a Koetsu Rosewood Signature Platinum so well (with dual pivot), it impressed the hell out of me (I’m a Koetsu collector).

Of course upgrade urge hit fast and I bought a brand new 10" Fatboy Gimbal. It’s a great arm, I really do think Fatboys are the best sounding VPI arms. However, it’s not as quiet as the metal wands in this feedback problem, and it’s not as bad as the original 3D arms. It falls in between. The Fatboys have more rigidity which helps. I think with HW40 feet and Fatboy combined you’ll be fine. That was the case for me.

Of course THEN I snagged an Avenger Reference plus a couple 12" wands - lovely table but same arm feedback issues persist if you’re not careful. And unfortunately, I don’t think those fancy $2300 Reference feet are as effective as HW-40 feet at these feedback frequencies. So I’m really right on the edge of usability with a 12" Fatboy Unipivot (dual pivot). Even my SUT placement next to the table (I guess the lighter SUTs can pickup energy from the shelf and feedback in via cable) can make or break it. Meanwhile I have a JMW-12 metal wand that’s always silent and happy, no problem lol. MANY cartridge and phono stage combinations were tried here. It’s the wands. The Fatboy Uni is a GREAT sounding arm when I can get it right, though. I like it slightly better than the Gimbal. Gimbal vs. Uni vs. Dual doesn’t seem to impact the feedback much. I think materials and structure of wand is what matters here.

However, it does make me think since the 3D and Fatboy arms are a composite structure (reinforcing rods, etc), there COULD potentially be variance across units - some being quieter than others! Hopefully the Fatboys are more consistent because I really like them.

@mulveling 

man you are REALLY making an argument for just remove the Lyra Delos from the 3D arm & put it on my 10.5 JMW-10 metal arm (I was mistaken not a 10, it's a 10.5")

Also , my floor is all wood where table (also wood) is on , so Im sure that's not helping matters...

 

I listen very loud at times...

man you are REALLY making an argument for just remove the Lyra Delos from the 3D arm & put it on my 10.5 JMW-10 metal arm (I was mistaken not a 10, it's a 10.5")

@tommypenngotti  Yeah man! I'm 99% sure you'll be rockin' and loving it with the Delos in your 10.5 metal wand. Even better if you fit those HW-40 feet.

Also , my floor is all wood where table (also wood) is on , so Im sure that's not helping matters...

I listen very loud at times...

Yep I assumed these, because that's how it is for me too lol. I even have my rack well separated from speakers and down a side wall, but that energy travels the distance quite easily. 

VPI makes a 2nd pivot for their arms.....relatively cheap and is a very good upgrade....that will stabilize the arm.  Also, I would change the rear weight ...something heavier, then lighter to get the arm to respond differently to the cartridge. (Use clay or something and dial in the arm properly). I have a Superscoutmaster with rim drive classic platter speed controller et al.  The table was very slow and the speed controller made little difference....VPI wanted me to send back  almost 70 lbs or so table back to VPI after saying my speed controller was running perfectly.  I felt that friction was the culprit, and after cleaning the bearing et al with alchahol, it was still very slow. I'm a gun shooter and decided to use Hoppes #9 bore cleaning to clean it up.  It did a fabulous job, the table is silent and running true.  Try different things on your table and you'll hit the answer.

I haven't heard YOUR table / arm combo with a Delos.  But I have not had good experience with Lyra cartridges with the VPI 12" unipivot arm (VPI Aries Extended).  Have not heard ANY Lyra cartridge work well with a VPI unipivot arm on any table.  I switched to a Jelco TK-850L and both the Lyra carts I currently have just love it.  

I have heard VPI unipivot arms work VERY WELL with AudioTechnica MC carts.  

@bpoletti

Thanks for the info ....again strange because not only does VPI use the Lyra mention in their manual for the Prime Signature model, I hear consistently it’s a go to for VPI tables...

Might be the 3D printed arms don’t do as well with Lyra on wood floors etc... ..🤷🏻‍♂️

@tommypenngotti 

My direct experience was with a Lyra Clavis Da Capo and a Skala.  Both were defocused and thin sounding on the VPI JMW 12 on an Aries Extended (original).  On a "custom built" table using original VPI TNT components and a Jelco TK-850L, both opened up, had great tonal body and remarkable imaging and soundstage. 

Maybe the VPI / Lyra recommendation is associated with the gimbaled arms.

 

 

 

Later that night at higher volumes I'm getting a midrange-low feedback

@tommypenngotti Since this is volume related it leads me to think the turntable isn't well isolated from room/air -borne vibration. If it were me I'd be looking at things to improve its isolation- better feet, an anti-vibration platform, that sort of thing.

I know you don’t want to hear this but 

a current driven  phono stage like the little Loco by Sutherland will in essence set itself.  I’m running a Lyra Delos through 

the little loco and it’s pure magic. Sooo

if your phono stage is the culprit I would look at a trans

Current driven phono stage

good luck Willy-T

@willy-t 

thanks man , my current philosophy isn't condemning my phonostage. I think it's positioning / tonearm related... 

I thought you said above that  the Allnic and the Delos aren’t jiving

thats the reason I suggested the current driven phono stage 

hood luck Willy-T

Are having any footfall problems as well (do you have to tiptoe around your phono setup when it is playing to avoid skipping?).  It is common to have footfall problems with suspended wooden floors and this can complicate the solution because solutions that reduce your feedback problem may worsen any footfall problems.  With a wooden floor, it is probably best to put the table on a wall mounted turntable shelf--that would reduce feedback that is coming from the floor (your floor is like a giant sounding board picking up vibrations from the air as well as from the speaker cabinet that is grounded to the floor) as well as any footfall problems.  As I mentioned before, you can also work to make any rack your table sits on less prone to shaking (attach it securely to the wall).  After you have a solid foundation for your table, you should then try various shelves and platforms designed to damp vibrations.  It is hard to say which will work best as this is a matter of system- specific tuning.  

@mijostyn @atmasphere @mulveling @lewm @tablejockey 

 

So I just bought a 2" butcher block that's (solid AF) & 4 IsoAcoustics pucks, mounted turntable , put stylus down on non spinning record at loud volume tapped around & a/b'd against no butcher block...don't really hear much difference 🤷🏻

@tommypenngotti You learn something everyday. I can slam my Sota with a mallet and you can not hear a thing. That is because the "butcher block" is hanging inside from 4 springs. Edgar Villchur was fascinated by the problem (which he also created with his loudspeakers) and Came up with the AR XA in the late 50's. It sold for something like $67.00 and within a couple of years everybody had one. They were outperforming turntables costing over $500. You could not get one to feedback if you tried and they didn't sound like an express train in the background. I never got an AR. My first suspended table was a Linn LP12. You need to get a real suspension platform. I am familiar with MinusK and Vibraplane. To isolate a turntable you have to use a mechanical filter, three of four springs tuned to a resonance frequency below 3 Hz. Bob your head three times in a second. That fast. You have to use springs just stiff enough to support the turntable.  

So I just bought a 2" butcher block that's (solid AF) & 4 IsoAcoustics pucks,

@tommypenngotti Just so you know, a 2" butcher block doesn't do much to kill vibration. If you bonded it to a substantial slab of marble or Corian (or other dissimilar material) the two materials could rob energy from each other and thus actually be able to absorb resonance.

I had a problem with foot falls near my equipment stand being audible despite some very nice anti-vibration platforms (I didn't have a problem with feedback otherwise). That was solved by placing bearings beneath the equipment stand, which relieved side to side energy.

When I was having footfall issues in my office setup, the ISO Acoustics pucks didn’t do jack to help. A maple butcher block was also completely ineffective. The shockwave of heavy footsteps on bouncy floor induces a (relatively) huge displacement (mostly lateral) in your turntable / tonearm system. The displacement is going to excite every subsonic resonance (e.g. cartridge suspension) and cause skips. It also excites a Clearaudio ceramic-magnetic bearing, btw. And also their magnetic bearing tonearms (good luck with that lol).

Spring suspensions (and maybe roller bearings) can help to some degree, but they won’t always be enough it if the problem is really bad. The old "bang a hammer straight down on the plinth" test is NOT a good simulation of this issue - though it was great gimmick for selling tables! Other platforms (e.g. butcher blocks, HRS, Symposium, CMS etc) and isolation feet are completely useless here. Bracing the rack against a strong wall, or a solid wall mount, is the only "real" solution in these scenarios - because they’re the only techniques that limit the displacement. One of worst audiophile "anti-patterns" might be sticking a turntable atop a tower style rack, unbraced. 

But OP’s problem is NOT that. It’s a resonance - in the audible bass frequencies - which I’ve noticed myself in the VPI arms, especially the 3D printed ones (especially the earlier ones - it’s a bit less on Fatboys).

You know, a lot of people switched from the VPI metal arms to 3D printed and commented that drums sounded so much more real and powerful! Well, guess where that resonance frequency is positioned and and what it sounds like...lol.

@mulveling 

I think Im chasing ghosts here...rabbit hole of trying to isolate came up with Hana ML & metal tonearm (which does not feedback) just looking for best possible isolation. When I get the Lyra back I'm going to switch it from the 3D printed arm to the metal arm to test...but I think I already know the answer 😃 plastic vs metal. 

end result - 

received completely rewired arm back from VPI and it works fine with Lyra now 

2 variables : 

1. Changed out to HW-40 feet 

2. Moved TT to middle of cabinet away from speakers

So ,something weird with the wiring causing the original problem-feedback?

Good to see you can now enjoy the setup.

CRANK IT UP!