@mulveling Thanks for the pictures and clarification. H
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):
What Underperformed:
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.
@mulveling Thanks for the pictures and clarification. H
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Hello again Mulveling, Last night was a different sort of night. Although it didn't involve vinyl, it did involve one of my favorite forms of music, blues, and one of my favorite players of it, SRV. Since my 3C24 tube amp was recently altered by its designer/builder, Paul Birkeland of Bottlehead, I am now sensing an emotional sensation I've never quite had before with SRV, or with my system. For me, that kind of sensation (to that extent) has rarely been noticible as it was last night. What Paul did was change my 3C24 amp to run 812 output tubes. It's changed this amp in a phenominal way to something that invites that kind of connection. That's what it's all about, is it not? Keep that enjoyment going, regards, Dan |
Thank you so much for sharing the link! I’ll give them a try and report back 👍 I’m curious… 1. Did you place them directly under the turntable’s feet or just under the plinth? 2. I see this company has rubber/steel/rubber pads as well. Did you happen to give those a try? Thanks much and best wishes to all! Don |
Yes, I placed the pads under the feet of the turntable, and noticed a significant audible change, but this is largely because I had a Rega P8, which is very sensitive to the surface that it’s sitting on. Try both, and see what you notice. It’s quite fun to experiment with little, inexpensive adjustments to the audio system! I only tried the rubber ones mainly because they were suitable for the lowest load psi, and designed for small vibrations and designed for acoustic applications. The steel ones have a minimum load of something like 200 psi, as opposed to 2 psi for the rubber ones, and also there isn’t any mention anything about acoustic application or vibrations for the steel ones. |
It all counts, everything. Isolating turntables from the environment is very difficult. You are trying to keep it from doing what it was designed to do and that is measure vibration. Concrete slabs are a great help with stability. Stability and isolation are two different issues. Foot fall problems are a stability issue. Feedback problems are an isolation issue. Some solutions affect both issues but are very interdependent. Concrete slabs are worthless if you have a wobbly rack. Your 10 year old should be able to run into the whatever the turntable is sitting on without making the turntable skip. That is the ultimate stability. This in no way guarantees good isolation. Concrete slabs do not isolate you from environmental rumble. Those of you with concrete slabs and subwoofers, put your stylus down on a stationary record and turn the volume all the way up. If you have a high pass filter turn it off. Look at your subwoofer bounce. Ideally they should not move at all. Turn on the AC and watch what happens. Check out the washing machine and the dishwasher. Only isolation platforms on ultimately stable platforms, tuned to a very low frequency will extinguish this. 1 to 3 Hz is the range most quote. The MinusK is so good at it because it is tuned in both the horizontal and vertical directions but put it on an unstable platform and it is a nightmare. Same goes for any suspension turntable although some are better at handling unstable platforms than others. @mulveling, I am not sure why you had so much trouble with the Sota. Did yours have the magnetic thrust bearing? Eclipse drive? I did have an issue with feedback at a very low frequency with the Cosmos. It turned out to be the three chambers acting like a Helmholtz resonator. Putting a skirt around the plinth closing off the cavity below the turntable fixed that problem. Otherwise, I have been totally pleased with the table. I also have an ultimately stable cabinet on a concrete slab. The subwoofers remain fixed with the above test regardless of anything else going on including the 10 year old. As for sound quality, it has none. Turntables are not supposed to sound. Any differences are usually easily proven to be from tonearms, cartridges and adjustment. |