Mass Damping

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From user LL21 on WBF

Stillpoints: Isolation and How do YOU do it?
Its taken a lot of systematic experimentation in my own system to get to the current level of isolation. I know exactly what tone I want the system to produce...its my primary #1 goal of all...and I find that isolation simply allows that tone to come thru clearer and stronger each time I isolate a component. But there are a lot of dead-ends and pitfalls I have found along the way...namely because every isolation material has its own pros/cons that affect the sound.

(Note: all my electronics are already in a custom rack: 4" thick birch ply sitting on top of 2" slab of slate.)

Here are my own conclusions to date:

1. Isolation Sandwiches work best for me. Basically isolation underneath and damping and often 'mass damping' on top.

2. Each material has slightly sound-related tendencies to either: adjust the tonal balance (typically when made purely of metal) or not to be quite as perfectly clear (pure elastomer only).

3. Mass Damping works extremely well...Adding pure weight on top of a component...but be careful.
When done right, mass damping helps to 'concentrate' the signal. Extraneous vibration are even more controlled/dampened. When its right, you will find a violin string crescendo at the very peak of the note suddenly takes on this INTENSE sweetness even as the note hits the high which normally 'screeches' just a teeny bit. The screech is not the string...its the miniscule vibration that then breaks up that last bit of note. (At least, that's my non-techie way of understanding it).

I actually discovered this when, by accident, I ended up with an extra Auralex platform and stuck it under my Gryphon Colosseum...greater depth (wow!) but lost tonal weight in keyboard. I placed an Artesania damping plate on top...it had helped smaller amps a lot...and it helped (a little). Randomly, I began pressing down on the top of the Gryphon...kinda thinking 'maybe more damping'...at first nothing. Then I kept pressing, and blam!...the strings hit a crescendo and there was this intense purity. I kept releasing and trying...and it kept coming back as soon as I hit that critical amount of pressure. I took a weight scale and placed it on top of the gryphon to understand how much weight I was applying. 20kg.

I have a mirror polished brass weight on top of the Artesania damping plate on top of the Gryphon now.

Now there are definitely some 'watch-outs' with mass damping.
a. Add a few pounds and you may hear absolutely no difference. I found on my components 20kg (45 pounds) makes the difference. Gryphon Colosseum and Tripoint Thor both have 20kg of solid brass on top. The Tripoint manufacturer actually supported my experiment when I told him my findings...I thought like many manufacturers he would deny it. Instead, he confirmed it should work and he does similar things, indicating that no matter how robust the casing, [properly] mass damping will add that extra bit of isolation that should work for the reasons above.
b. I CANNOT put the pure metal on top of any of my cabinets. I always have the brass on top of a well designed damper (Artesania, HRS). Otherwise, the sound hardens...its downright awful. very hard and unforgiving...deadens the decay of notes.
c. on the aesthetic side which for many of us matters...I use mirror polished brass scientific weights. I buy them second hand but in mint condition. I have 76lbs on top of the Velodyne, 45lbs on Gryphon, 45 pounds on Tripoint Thor

4. So what does an 'isolation sandwich' look like typically?
- Underneath: [HRS M3 with Nimbus Couplers] OR [Ultra 5s with HRS Nimbus on top of the Ultra 5s] OR [Ultra 5s on top of Auralex Isolation Platform]. As mentioned above, the Ultra 5s do alter the tonality just a touch in my system...just a teeny leaning out of the lower treble...piano loses weight and feels like electronic keyboard'ish. I read so many great reviews of Ultra 5...after buying them...I found 1 review (on the Stillpoints site!) noting this exact phenomena...and I am fortunate I have managed to fix it in my system because I love the Ultra 5s. Adding the Nimbus Couplers adds ALL that lower treble tonal weight back...but maintains ALL the clarity of the spectacularly clear, delineated Ultra 5
- On Top: HRS double-thickness Dampers, Artesania Dampers and sometimes Ultra 5...and sometimes mass damping too.

Again, I know exactly what tone I want the system to produce...its my primary #1 goal of all...and I find that isolation simply allows that tone to come thru clearer and stronger each time I isolate a component. But along the way to making the sandwich configuration, the tone will change...and it takes experimentation for each component's isolation sandwich to ensure the tone I want is maintained...while continuing to eliminate vibration, grunge, mechanical distortion...which again makes that tone sing thru even clearer, better and more beautifully/purely.

Nowadays, i can demonstrate to visitors that SLIDING AN ULTRA 5 across the top of one component makes a difference. It has become that sensitive to alterations in vibration. The Ultra 5 Distributor who came to visit was extremely surprised.

Conclusion
Every single component in my system is in its own 'isolation sandwich'...something underneath and something on top. That is 12 components...each 'isolation sandwich' is slightly different for that particular component. Even my Wilson X1s are on Ultra 5s...but I have also found that adding a 3lb weight inside the woofer port in the back helps 'still' the bass...note: adding 10lbs actually killed the resonance of the bass artificially so there was no natural decay...the bass roll-off just "dropped off" instead which was clearly wrong. I know there is huge vibration on the top of the big woofer cabinet, and if I could find a way to slide an Artesania damper plate underneath the main modules, I would try it.

My two cents. Hope that helps some fellow members who are experimenting with isolation. Last edited by LL21; 03-15-2014 at 12:36 PM. Source: Zanden 4-Box Digital Amps: CJ GAT, Gryphon Colosseum Speakers: Wilson X1/Grand Slamms, Velodyne DD18 Isolation: (9 'Isolation Sandwiches') UNDER: HRS M3/Nimbus, Stillpoints Ultra5, Auralex; TOP: HRS, Artesania, Finite Elemente, EAT, 154lbs brass mass damping Cables: IC: TA RefMM(MM2), SC: TA RefXL(MM2), Power: PAD 25thAnn/AnnivCont/Dom, SablonAudio GCUber Power: Tripoint Troy SE (Thor), TA Ref PowerIsolator, Nordost QX4 Tubes: Amperex 7308 US PQ White, Mullard 1950s 6CA4/6922/6X4
 
The Tripoint Troy he mentions in his system is a grounding box that starts at 15k and if you add cables and all can range upto 35k or so
 
I should try a few of my VPI Bricks on top of my CDP just to see if I can hear any difference.
 
Make sure it's a lot of weight, he says 20kg for amps, you will need 10 or more for CDP - oh wait, that's 25 lbs or more
 
Be cautious of deflection on the top of the component though, especially if you're using a number of weights instead of one large weight.
 
Julian,

I've been posting there for awhile under "thedudeabides".

Very serious folks with many having systems in the six figure plus area.

Can't say I prefer it over the MLO site. Just different. Interesting how you have similar personality "types" on WBF that we have here.

GG

PS: Weighting the top of a component has its positives and negative and is totally audible. I've tried this "cheap" tweak on numerous occasions. You'll need to listen to determine if it's a plus or a minus. IMHO, should be done in tandem with cones or other similar devices under the component.

And yes Bernard, you should try it.
 
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Very serious, but very friendly and professional it would seem. The forum has a different scope of topics of course; more wide ranging, but the single focus of MLO is its' best feature IMO. I have seen a few friendly faces over there.

For mass loading, COULD it be beneficial to load the tops of my Vistas' woofer enclosures? What I have in mind is to place a piece of 2" steel plate measuring 11" x 9.5" on each enclosure, which would give me approximately (or exactly :) ) 59 lbs of loading per speaker. I will coat them in polyurethane to prevent Unsightly Blemishes. Only way to find out is to try, I suppose.
 
Very serious, but very friendly and professional it would seem. The forum has a different scope of topics of course; more wide ranging, but the single focus of MLO is its' best feature IMO. I have seen a few friendly faces over there.

For mass loading, COULD it be beneficial to load the tops of my Vistas' woofer enclosures? What I have in mind is to place a piece of 2" steel plate measuring 11" x 9.5" on each enclosure, which would give me approximately (or exactly :) ) 59 lbs of loading per speaker. I will coat them in polyurethane to prevent Unsightly Blemishes. Only way to find out is to try, I suppose.

Julian,

Worth a try. I did that with my SL3's. Very audible difference. Only question is if you like or not.

Regarding speaker damage, go to a hardware store and buy some small rubber feet with an adhesive on the back side. Stick those onto the plate and you're in business.

Gordon

PS: Another option is to go to a store that sells granite. Go through their "scrap" pile and have them cut to size. Cheap and good looking.
 
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