Coupling vs Decouplling: What you need to know
 

I found this video* on YouTube to be of quite a bit of interest today.

So, ya think those ultra-trick loudspeakers and subs with extremely stiff cabinets or cement-cabinet loudspeakers are "non-resonant"?

Think again.

http://avroomservice.com/evp-2/

Botton line: Everything has a resonant frequency, including...Mt. Everest. Or, think about what happened to the concrete and cement buildings in San Francisco in 1906 or 1989.

I've noted that the A/V RoomService's EVPs have gotten excellent reviews at The Absolute Sound, so I'll be ordering some of those. Its clear to me that Norman Varney knows what he's talking about; he thinks like a scientist and he does informed and insightful experiments.

So....I've got a music box mechansism arriving from A'zon tomorrow, and I'll doing some experiments.

I've also ordered some of the cork & rubber and Diversitech anti-vibration pads (https://amzn.to/2NNegMq). I was at a SFAS meetup on Saturday where loudspeaker guru Andrew Jones was speaking, and he was using the Diversitech pads under the ELAC Alchemy DAC. If they're good enough for Andrew Jones, they're good enough for me. I'll also be testing my Herbie's Audio Labs Tenderfeet as well that I use under my SOtM SMS-200 UltraNeo network bridge, EtherREGEN Ethernet switch, Schiit Gumby, and Keces P3 power supply.

*–If you want, you can skip the first 5 minutes where the New Record Day guy explains why he didn't make a video about these sooner. It's frou-frou...

Supply House plumbing supplies on Long Island has many vibration pad options. Shipping on orders under $99 might be a little steep but the selection and prices are real good.

Good tip, John, thanks!

I've got some of the (traditional) cork & rubber and the Diversitech pads in-bound. They were cheap, like $6 for 4, IIRC.

I had a couple of sets of EVP's for about a year and they seem to do what Norman claims. They were a bit cheaper when I ordered mine though still less than other options. Jim Smith is a big fan of them.

Thanks, JMD.

I don't know Jim Smith, is he an AA member?

The room setup guy from Atlanta. Don't know if he is a member here or not but I though he was. Was the Avant Garde rep for years.

http://getbettersound.com/gbs.html

Stephen-

It will be an interesting comparison of the cork & rubber pads to the Diversitech version. Folks actually quiet down their furnaces with some 2 x 2 cork & rubber pads.

If these are the same - they are really cheap:
https://www.supplyhouse.com/DiversiT...xoCP7kQAvD_BwE

John-

Exactly what I was thinking. That's why I ordered both! :D

Going to do some experiments. I downloaded VibSensor app for the iPhone which uses the accelerometer to produce vibration measurements.

Shown here is the difference in vibration from me rapping the top shelf of my Sanus Euro II audio rack, and then rapping a ButcherBlock Acoustics 1 3/4" thick rock maple board sitting on cork & rubber anti-vibration pads. The red trace is the top shelf, the blue trace is the maple board.

https://photos.imageevent.com/puma_c...le%20Board.jpg

And, shown here is me dropping a weight onto my audio rack top shelf about the distance of 1", and measuring the vibration on top of the Schiit Gumby DAC. Red is the amplitude and ringing from the Gumby sitting on its own rubber feet on the Sanus Euro II rack top shelf, and the blue trace is with the DAC sitting on Herbie's Audio Labs Tenderfoot component isolation footers. You can see the amplitude and ringing is notably lower with the Herbie's Tenderfoot footers. Today I am going to do a DOE using the footers with and without an ButcherBlock Acoustics hard rock maple board. The maple board will be resting on the cork & rubber anti-vibration pads or the MIG footer. Once I get the Diversitech pads, I'll do some more experiments comparing the two different types of pads. :D

https://photos.imageevent.com/puma_c...Tenderfeet.jpg

Pretty cool, eh? ;)

Cheers. :thumbsup:

Yep, those are what I ordered. :thumbsup: