Turntable Isolation Journey


Nearing the end of my journey to solve footfall & feedback issues in my small-room "home office" system with very bouncy floor and flexible walls. Turntable is the only source here -- and it’s a Clearaudio Innovation Compact with no suspension or special isolation feet. This system always sounded good, but was rendered nearly unusable at higher volumes due to turntable isolation that was inadequate relative to this room’s challenges. The worst artifact was when structure-borne feedback from the speakers would cause amp clipping on bass-heavy tracks. This clipping would manifest as an extremely loud singular POP sound, especially hitting the tweeters. It only occurred during the loudest parts of track with bass-heavy elements, and was so loud it was still significantly above the level of the music -- much louder than a POP you would hear from vinyl surface defects. The POP sound was startling, and clearly very bad for tweeters (fortunately my Tannoys seem to have survived several of these incidents). For a time I thought these POPs were from static electricity discharge, but they were NOT. In my quest I tried many solutions and tweaks over a few months, and I’d like to share a rundown of what worked versus what didn’t.

What Helped (MVP products & tweaks):

  1. Townshend Seismic Isolation platform -- Single biggest difference maker, for combating both footfalls and structure-borne feedback from speakers. Amazingly-well designed and built. Leveling was a snap. Well worth the price! If you spend money on isolation, spend it here. Highly Recommended. I’m now considering more Townshend products for under my speakers and in the big loft rig.
  2. Rack Bracing -- Pushed rack right up against the wall (stud / drywall) with a 2’x2’x2" Auralex foam panel tightly wedged in between the top half of rack & wall. This SIGNIFICANTLY cleaned up rack oscillation from footfalls. I see a LOT of folks with nice turntables atop tower-style audio racks, and they could benefit greatly from this "hack". It is cheap & free; the only downside is you may need to reposition your rack. I learned about this "hack" by a couple comments buried in "turntable isolation" threads searched via google. This really CANNOT be overstated.
  3. HOCKEY PUCKS -- Placed under rack spikes in place of the stock aluminum cups or Herbie’s Giant Gliders. Just let the spikes sink right in! This actually cleaned up the very last bit of energy from footfalls; foot stomps with needle-in-groove are now DEAD QUIET. super cheap and effective! Far superior to most audiophile footer devices. Might also help in rack bracing by tightly constraining the rack between wall & floor (Herbie’s Gliders were too slippery).
  4. Rack positioning -- Get your turntable & rack away from the speakers. If you can move the rack far enough behind your speakers, that might be OK, but most rooms cannot accommodate enough depth for this. Placing the rack several feet down a sidewall worked best in this room. Choosing a structural wall also aids in rack bracing. Make sure you don’t place the rack in a room "node" where bass is amplified. Walk around while music is playing to find a nice quiet-ish spot. I kept my amps by the speakers and ran 5 meter XLR cables from the preamp / rack.

What Underperformed:

  • Critical Mass Sotto Voce rack -- the rack is gorgeous and nicely rigid, but doesn’t have nearly enough mass to combat the bouncy floor in this room. Once braced against a wall, the rigidity of this rack was allowed to shine. However, before the bracing, its performance was poor. I will say I have Critical Mass’s Maxxum rack in my (main) loft system on a more solid floor, and the immense mass & rigidity of that rack was game-changer for that system. I do like CMS products, but they are dearly expensive.
  • Critical Mass Black Platinum filter -- Top shelf of the rack. This actually has a significant positive effect, but is limited to the midrange and treble frequencies. It cannot combat footfalls or low frequency feedback. I still like and use this platform, but at more than twice the cost of a Townshend platform it belongs in this category.
  • SOTA Nova V Turntable -- I thought this table’s suspension would render it impervious to room issues, but it’s not. It helped with footfalls but some structure-borne feedback was still getting through. I suspect the suspension needs a tune-up. Quite frankly I think the OLD suspension (it started life as a 1990s Star III) was better tuned and more stable before it came back as a fully rebuilt Nova V, circa 2018. The new vacuum platter was a huge improvement but the new suspension has been disappointing. The Clearaudio deck also sounds a bit better, so now with the Townshend platform it’s an easy choice. Note that the Townshend also uses springs as its isolation mechanism, but I noticed that the Townshend’s oscillation is far better controlled and damped versus the SOTA. You can SEE and HEAR its performance advantage.
  • ISOAcoustics Gaia III speaker feet -- these seemed to have some small positive benefit, but honestly not a lot. Not worth the money.
  • Lovan Sovereign modular rack (three 10" modules high) -- these are very similar to the VTI racks I see everywhere (which I’m also familiar with). These racks lack rigidity and stability. I would not recommend placing a nice turntable on one of these racks. However, if you do, please brace it against a wall (Auralex foam works great). They’re relatively cheap and look good, so I at least understand their popularity. If you have this rack, at least try hockey pucks under its spikes :)

What Was Worthless (Don’t waste your money like I did):
I’m not going to bother expanding upon these; suffice to say they had no discernible positive effect.

  • ISOAcoustics Orea Indigo feet (under maple board & turntable).
  • Symposium Segue ISO turntable platform
  • Herbie’s Lab Giant Gliders (steel) - Placed under Sotto Voce rack spikes
  • Speaker spikes -- at least they look cool :)

128x128mulveling

mulveling, I'm late to the party but want to add my thanks for your information and starting this helpful discussion.

Somewhere I read a recommendation for this product.  I've not tried it but it seems to be a very inexpensive device to try.  It is similar to those suggested by drbond.

https://www.amazon.com/Pack-Anti-Vibration-Rubber-isolation/dp/B01IU6WT5O/ref=sr_1_2?crid=14TMEUKR93JE3&keywords=isolation%2Bpads&qid=1684506769&sprefix=Isolation%2Bpads%2Caps%2C103&sr=8-2&th=1

I recently bought a Technics SL-1200G which is mounted on a Target stand.  It is a new home with engineered wood beams in the floor and I don't feel any spring or flex.  Of course that could exist in modest measure.  This system sounds very good, but it might be improved further.

@pryso The sandwich type pads are an interesting alternative to hockey pucks. I'm all for these effective & affordable products. They're probably at least as effective as most audiophile footers ($$$), if not MORE so in many cases. Of course if you have severe energy issues (like in my room here) they'll hit their limits and then it's time to explore more significant (and costly) options like the Townshend. But for moderate energy issues, I think these cheap products are fantastic. 

Sounds like you have a very structurally sound room and you've smartly used a wall mount to boot. I bet that is a great setup! Enjoy :) 

@mulveling, yes Target make wall mounts but mine is a 5-shelf floor model.  The unit itself is steel I believe and quite heavy, so with added components (the Technics is surprisingly heavy) the total mass is substantial.

Then beyond the turntable I need to experiment with the amp and speakers (currently factory rubber feet).  Minimizing vibrations seems a good idea with everything but the stylus. ;^)

 

@mulveling, yes Target make wall mounts but mine is a 5-shelf floor model.  The unit itself is steel I believe and quite heavy, so with added components (the Technics is surprisingly heavy) the total mass is substantial.

Then beyond the turntable I need to experiment with the amp and speakers (currently factory rubber feet).  Minimizing vibrations seems a good idea with everything but the stylus. ;^)

Ah, my bad - my brain filled in "wall mount" when it saw "Target" because they're known for that. Anyways, sounds like you have a structurally sound floor, which is worth its weight in gold for these applications. Definitely, amp & speakers are worthy of experimentation too! :) 

@mulveling When extending the investigation of Structures, to the experiencing how these can impact when used under Speakers, if the design is a Cabinet Type, either Stand Mounted or Floor Standing. To date, I have not encountered a demonstration using suspension under the Cabinet that has not had a positive impact. The suspension has an immediate effect on the tidying up of the lower frequencies, the change for the betterment is immediately discernible.

The benefits of this overall takes a little time to assess, in my own system working with my Floor Standing Cabinet Speakers mounted on a Two Tier Plinth Structure, the addition of AT 616 Footers was the 'cherry on the cake', the overall presentation become gathered and the Bass Notes jumped out as having a perception of being quite honest as a rendition. Further extended listening was leaving the perception the Mid's and Upper frequencies were more projected and with a much improve detail being discovered. Notes/vocals were noticeable for having a envelope that could be traced as the sound formed into something that has a sense of being tangible. The sound produced, certainly was seeming to be coupled to the room with an improvement and this was undoubtedly more attractive to experience.

Valve Amp's are really going to Benefit for the Structures placed under them.

I have done a lot of work with all Valve Amp's/Valve Devices owned, to keep it simple and to create a worthwhile experience, the Phonostage is a good device to use to learn from. It can soon be learnt where the detail able to be produced is to become smeared, or much improved upon, through the use of differing materials and configurations for the structure.

@pindac, by Cabinet Type I assume you mean any traditional box speaker, not a panel speaker.  That is not a term I usually see.

I've read other positive comments on the AT 616 footers over the years but they are difficult to find I think.  Not sure how long they have been out of production?