Sound isolation tip from a dance club DJ installer

I stopped in my local Guitar Center yesterday (where I bought my Technics SL1210 M5G a year ago) to see if they carried the ART Pro Audio SLA-2 amplifier. I soon struck up a conversation with their sound equipment/dance club gear guru and we started talking about the totally inadequate feet on the Technics SL12x0 series and ways around them.

He mentioned that what he did on a permanent (as opposed to mobile) dance club installation where he was getting too much feedback was to get a couple of gel-based keyboard wrist rests from his local OfficeMax, took the feet off the turntable and set the turntable base on the gel wrist rests, which were like plinth-wide footers. In his case he also stuffed fiberglass insulation under the bass in between the gel pads to kill standing waves under the TT base, but he said it fixed his feedback problem.

As most of you know, I have an SL1210 M5G with PartsExpress/Dayton threaded brass speaker cones onto a cutting board. Until about an hour ago I had Vibrapods under the cutting board, but now I have a couple of gel wrist rests instead.

Before I made it a permanent change, I put a record on, set the stylus on the record, and tapped the shelf that the turntable is on to see how much "thump" came through the speakers. Then I swapped in the gel pads for the Vibrapods and tapped again. Definitely lowered the "thump" by somewhere between 2 and 3 dB, which is about what Isonoe measured (with the sorbothane boots) for their $175 footers.

Definitely a little cleaner, clearer, etc. Tweaks are cumulative and I got my money's worth with these.
Thanks for the tip!
Hi everyone

I just had to bump this thread. I tried parts of the tweaks mentioned above and it really worked for my TT set-up. I’m hoping it can help others as well.

I have a direct drive Concept 2QD TT with busted shock absorber feet and I replaced them with some unused rigid metal feet that were from my Studiotech cabinet. I put the whole set-up on my isolation platform (maple cutting board, 16" x 16" x 2.5") and I had accidentally hit the TT and heard the thumping noises. No matter the area I would tap on the 2QD the thumping could be heard through my speakers. I was worried about other feedback as well as my speaker is within close proximity of my 2QD.

I found this thread along with some others by forum member Johnnyb53 and I took a page from his playbook.

I purchased a pair of Staples brand Deluxe Gel Keyboard wrist rests as they are the thickest out of the bunch being sold there. They had the most gel padding as far as I could tell and are 20" long and 3" wide. I put 2 of them under my isolation platform. The gel side facing down touching the shelf and the gripping side was touching the isolation platform. I put the 2QD with its new feet on this set-up and tapped away and there were no thumps. Only when I tapped really close to the cartridge did I hear a thump. I think most of the feedback is now gone and I’m relieved.

Trying to get this Concept 2QD up and running with no issues has been quite an annoying ordeal this past couple of days. It cost me $36 but I'm very happy now. The wrist rests I got were the most expensive and you could probably use different/cheaper ones but I didn’t want to take a chance.

Thanks Johnnyb53 for this thread and other posts about isolating a TT. They helped me out a lot.