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

You play a lot of music at loud levels in that room?  Not much I can see will help with airborne interference.  Maybe a nice digital playback source.

You play a lot of music at loud levels in that room?  Not much I can see will help with airborne interference.  Maybe a nice digital playback source.

Since the structure-borne energy has been addressed, airborne energy doesn't seem have been be a big problem. The rack with turntable is located several feet down the left side wall. And I don't want a digital source lol. 

Any one use HRS platforms or racks.  I have a floating floor and isolation of my turntable is a challenge. 

@mulveling I can't recollect when I first started to consider room treatments as a subject to be better understood. I have been to numerous Trade Events and have seen plenty of Commercial Products and Room Treatments utilised in Demo' Rooms.

In the early days visits to Commercial Events were more about learning how the Audio Devices were creating a signal and how the Speaker was able to produce a sound. It was these experiences that steered me to become a advocate of and remain loyal to the Vinyl Source as a sole source for more than 25 years. A digital Source is quite a new addition in my system.

As I learnt about Vinyl, the interest in the Mechanics of the devices used become quite developed and I met with many to learn how they were addressing the need to be creating interfaces that are crucial to attempt for an unadulterated sound being produced. This is a interest that is still strong today, there are plateaus that are camped on, but the getting to the Summit is still the climb to be undertaken.

Room Treatments have come into the equation when I was quite interested and practicing methods to improve mechanical interfaces. The curiosity was is the works undertaken due to the listening environment, hence, supporting structures and room treatments evolved as an interest and educational experience.

I highly recommend room treatments, there is extensive information on how to do DIY Absorption Panels and Diffusers. If this does not suit, there are also off the Shelf Absorption / Diffusers that will be quite suitable and not necessarily expensive. There is the trade off if a room is to be a main living area, as the method to conceal the treatments and blend them in as decor' might mean a little extra thought is needed for the aesthetics and if buying off the shelf this can be with increased costs. 

As stated before, if these subjects are addressed, support structure, and room acoustics, revisiting simple to exchange interfaces on the Signal Path, i.e, Cables, Valves, SUT,  will shine a new light on some of the earlier choices made.

The Link is not a recommended site to purchase from, but it will give a consolidated overview of how aesthetics can be considered.

https://gikacoustics.co.uk/?gclid=CjwKCAjw6vyiBhB_EiwAQJRopouz8t8L6CMjxTWSTCFXWP9EQTqtQZ9fA-JxNyPo42R66Q2bXH

  

Well thanks for the tip about spikes into hockey pucks for speaker footers! I’m amazed at what it did for a pair of Pure Audio Project speakers on a sprung floor. Just snapped everything into focus and took the goo out of the midrange. Much better than the stock feet. I am very surprised by this as I had long ago decided that rubber was a bad material in audio systems. I guess mental rigidity is bad too.