Input on amp stands

Christof · « **on:** 30 Jul 2004, 11:52 pm »

I'm working on a new type of amp isolation platform and would like to hear your personal input on amp/component platforms before I finalize the design. What do you like/dislike about current products on the market, do you think they are even necessary, what materials do you find beneficial, etc....
Thanks for your input, guys.

Christof

JoshK · « **Reply #1 on:** 31 Jul 2004, 01:05 am »

I think that amp stands really only make a big difference with tube or digital amps, more so with the prior. I myself only like thick wood platforms as I think other as merely different rather than better.

Oh, and effective amp stands need not be expensive and exotic. Those qualities don't make them better imho, only prettier.

Hantra · « **Reply #2 on:** 31 Jul 2004, 04:17 am »

I am of the opinion that in the most resolving of systems, stands can make a pretty substantial difference. Best I have used so far are the Ikea Lack tabletops on cones (see pic below). Bass like one wouldn't believe. I am considering the Sistrums now, but it's a big step, so I am a bit apprehensive.

beat · « **Reply #3 on:** 31 Jul 2004, 05:34 am »

I have been using granite slabs, glued to wood, then spiked with nice results. I have not done an A/B against wood alone but I want to try. Hey Hantra, what is the deal with the lack tables. I've seen 'em and remember the price is right but cant remember how they were constructed. Are they heavy?

Christof · « **Reply #4 on:** 31 Jul 2004, 02:00 pm »

Joshk, Hantra & Beat....thanks for your input.

It seems that amp stands are typically a thick piece of wood of some sort, be it a lamination, butcher block or simply solid wood panels.

I would like to know the science of the solid wood approach. It is my understanding that what provides mechanical damping is friction; viscous, dry, or other. The energy must be turned into heat by way of friction before it is arrested. A solid piece of wood, while adding mass, which does derease resonant frequency, does not allow for much friction, at this point a panel becomes less effective at reducing transmission than mass law would indicate. Then I am left with a final question with wood stands, it seems that many times they are made from very dense woods like Maple which increase the stiffness of the panel. If increasing stiffness increases resonant frequency, decreasing stiffness decreases it than why don't people use less dense woods like Alder or Cherry?

Chris

zybar · « **Reply #5 on:** 31 Jul 2004, 02:06 pm »

Quote from: Hantra

I am of the opinion that in the most resolving of systems, stands can make a pretty substantial difference. Best I have used so far are the Ikea Lack tabletops on cones (see pic below). Bass like one wouldn't believe. I am considering the Sistrums now, but it's a big step, so I am a bit apprehensive.

Nice pic B.

Did you have to saw the legs off or are they the type that just screws on?

How about a few pics from farther back?

George

zybar · « **Reply #6 on:** 31 Jul 2004, 02:25 pm »

Quote from: Christof

I'm working on a new type of amp isolation platform and would like to hear your personal input on amp/component platforms before I finalize the design. What do you like/dislike about current products on the market, do you think they are even necessary, what materials do you find beneficial, etc....
Thanks for your input, guys.

Christof

Christoff,

I am using two different stands right now.

One is just a 3" thick piece flat grained cherry.

The other is cherry boxes that I filled with sand, put 3/4" foam around the lip and "floated" a 1/2" mdf shelf on top of the sand.

George

Hantra · « **Reply #7 on:** 31 Jul 2004, 02:46 pm »

Quote from: beat

I have been using granite slabs, glued to wood, then spiked with nice results. I have not done an A/B against wood alone but I want to try. Hey Hantra, what is the deal with the lack tables. I've seen 'em and remember the price is right but cant remember how they were constructed. Are they heavy?

Beat:

They are not heavy at all. They are a pound or two. I have found that lightweight, rigid materials work best for my tastes. I am not a fan of big heavy slabs of ______ . These are a type of particle board with a veneer, and some of it is even paper. Interesting construction, but the sound is better than all the woods I have tried. I have used cherry, cherry ply, poplar, birch ply, redwood, and maple blocks. Right now I am using those Ayre myrtle blocks under my gear and I like those as well.

Z:

The legs screw on, so I never even had to do any cutting or tweaking.

Here are a couple pics. . .

lonewolfny42 · « **Reply #8 on:** 31 Jul 2004, 02:54 pm »

And B,

Christof · « **Reply #9 on:** 31 Jul 2004, 03:09 pm »

George

I like your idea of a sand filled panel. Can you comment on the differences b/t the two. I would also like to know how well the different materials slow or stop vibration. According to physics, the sand filled box should work much better as it allows for more friction = heat. What happens when you put your hand on top of the sand filled box and tap on the side of the box vs. doing the same thing with the solid wood?

thx...c.

beat · « **Reply #10 on:** 31 Jul 2004, 03:22 pm »

Quote from: Christof

I would like to know the science of the solid wood approach. It is my understanding that what provides mechanical damping is friction; viscous, dry, or other. The energy must be turned into heat by way of friction before it is arrested. A solid piece of wood, while adding mass, which does derease resonant frequency, does not allow for much friction, at this point a panel becomes less effective at reducing transmission than mass law would indicate. Then I am left with a final question with wood stands, it seems that many times they are made from very dense woods like Maple which increase the stiffness of the panel. If increasing stiffness increases resonant frequency, decreasing stiffness decreases it than why don't people use less dense woods like Alder or Cherry?
quote]

Hantras Lack tables seem to be increasingly popular for guys like us (as I understand it) I am wondering if the principle of light and stiff with good absorption is what goes on here. Rather than trying to combat all movement with pure mass, it allows it to some degree and dissipates it to the floor. Because it is light and stiff it would allow a higher resonant frequency which is more easily dealt with and subdued. I have been considering this principle in my next speaker cabinet project. Basically allowing movement, then killing it, which creates a more or less "live" box rather than trying to mass it to death.

Christof · « **Reply #11 on:** 31 Jul 2004, 04:04 pm »

Beat

I'm following you, basically using the principals of CLD (constrained layer dampening) which is seldom done due to the fact that it is quite difficult to construct, at a production level anyway. There is a good thread going at diyaudio on CLD construction

c.

Mike82 · « **Reply #12 on:** 3 Aug 2004, 02:52 pm »

FWIW, I'd look at the Mapleshade maple platforms/amp stands.

I recently tried a 4" thick platform under my MC252 and was quite impressed what it did with the sonics. Lower noise floor and better attack transients. The Mapleshade replaced a Grand Prix Audio amp stand (which was 3X the cost of the Mapleshade).

http://www.mapleshaderecords.com/tweaks/ampstands.php

KeithR · « **Reply #13 on:** 9 Aug 2004, 11:36 pm »

Off topic, but how do you like the new 3 Series?

Hantra · « **Reply #14 on:** 10 Aug 2004, 12:53 am »

Quote from: KeithR

Off topic, but how do you like the new 3 Series?

Hmm. . .

Well. . . Too early to tell. MUCH better than the new 5, but it's hard to say until you see it in person. The tail lights are just plain WRONG. What were they thinking!? And at least it doesn't have the Uber-Feminine "eyebrows" that the 5 has.

Tell you what I really like. . . The '05 997!!!! The more I see that, the more I want it. And I am not even sure that 400bhp in an E90 M3 could sway me. .

What about you?