Foam tweaks

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Alsatian
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Post by Alsatian » Tue Dec 02, 2003 11:06 pm

You are right, each shelf will cost about $80. I should stop trying to do two things at once... :unsure:

MRI

Post by MRI » Wed Dec 03, 2003 5:00 pm

I wanted to make a plug for trying the blue pucks.
I received 4 from Kevin (thanks) and tried them under parts of my system:
Sim/Moon Nova, CS pre, 22 mk2, Spendor 3/5, all BC wiring.

Under Nova: wrong thing to do. Treble went away and the bass got bloated.
Under 22: nothing at all.
Under CS: wow, that's all. Tighter everything. A bit tipped to mids and highs. But clean and defined. Excellent instumental/voice timbre and spatial localization.

I would recommend a trial of these as more expensive may not be all that better. BTW I used to use Mana. :angry:


MRi

Post by MRi » Mon Dec 15, 2003 11:29 am

Just wanted to add to my last post. I repeated putting the pucks under the 22, but cut two of them in half to give four smaller pieces. This combination with the others under the preamp makes a very coherent system. Listened to Intimate Ella, Errol Gardner (1960's) and a new EMI Sara Chang Dvorak last night. Never sounded better.

The pucks under the preamp gives the same kind of suspension that I have seen using the Quadraspire Reference stand for a whole lot less $$.


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esoxhntr
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Post by esoxhntr » Mon Dec 15, 2003 8:47 pm

MRi:

I think you make the most important point of all - none of these things work the same way in two different systems, or even for two components in the same system. The willingness to experiment is paramount to make the foam work properly. It WILL work, but you have to play with it to optimize it for your own gear.

Fortunately, with the price of the foam pucks you can afford to experiment all you like for low $$$. My own favourite low $$$ tweak was to replace the shelves in my stand with 3/4" MDF. Also, try putting a few pounds of lead fishing weights on top of your CD transport.

Dave

Post by Dave » Sun Jan 04, 2004 11:50 pm

Alsatian,

I've seen a number of DIY Symposium shelf clones on Audio Asylum. Everybody seems to have their own version of the Colonel's secret receipe. Which one are you trying? I might be interested in making a few prototypes as well . . .

I wanted to "test" the hypothesis that was explained at Symposium's web site (it touched on Snell's law and concepts of entropy so I was impressed). So I laid a couple of layers of thick bubble wrap over my audio shelf. I placed a 1/16" thick piece of aluminum on top of the bubble wrap. I placed my SET pre-amp over the plate and placed cones in between with points facing the aluminum plates. WOW - what an improvement in bass response and high end clarity compared to the cones alone! More bass, harder dynamics and more mid + high end detail . . . that's an interesting improvement - no compromises!

My pre-amp is a N.E.W. P-3 SET. I used to talk trash about it but the more I tweak it, the more my respect grows for it. I also use a cheesy XLO power cord (which sucks, I might add) + a HAL-O Nine tube damper on my ballast tube + elastic bands on my relatively cool output tubes (hey what can I say - my BC28 power amp needed some tube dampers!).

Anyway, let us know your DIY Symposium shelf clone recipe. I'm considering a modest TNT-Audio DIY FLeXy double rack with DIY Symposium clone shelves. I need to build a new rack to accomodate this monstrously large BC28 amp. Here's a picture of the concept . . . though I'll have to extend the bottom layer width (and maybe thickness) of the Symposium clone shelves to accept support bolts. http://www.tnt-audio.com/gif/2flexy.jpg

Regards,

Dave

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Alsatian
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Post by Alsatian » Sun Jan 11, 2004 5:00 pm

Thanks for reporting on your experiment.

My recipe for the symposium platforms is:

Aluminum 1/8 inch
Duron hardboard 1/8 inch
MDF 1/2 inch
Gatorfoam 1/2 inch
MDF 1/2 inch
Duron hardboard 1/8 inch
Aluminum 1/20 inch

I have been pretty busy lately so I haven't been able to work on the project. I purchased the gotorfoam from Dakota art supplies online. They have smaller pieces at reasonable prices, 16" by 24" for about $12. The aluminum is on order from Speedy Metals from eBay. Everything else I found at Home Depot. I didn't find any 3/4 inch MDF, but I must confess I didn't look that hard.

I would be happy to post my results after building them.

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Gilbert Y
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Post by Gilbert Y » Wed Jan 14, 2004 12:01 am

Alsatian

3/4" MDF may be actually 11/16". Look for 11/16" MDF from Home Depot next time you are there. When I order my MDF, I ask for 3/4" and always got 11/16" or slightly thicker. Never a full 3/4" thick.


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Alsatian
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Post by Alsatian » Thu Jan 15, 2004 11:54 pm

Gilbert,

Do you think there would be any sonic difference between the supposedly one half inch versus the three quarter inch? According to a couple of posts on Audio Asylum, Symposium's recipe calls for three quarter inch. Thanks.

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Gilbert Y
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Post by Gilbert Y » Mon Jan 19, 2004 8:55 pm

Alsatian

I am not sure there is any sonic different between 0.5" and 0.75" thick MDF. I always buy 0.75" thick because I notices if I use 0.5" MDF, something the middle will bend if the amp being too heavy. 0.75" thick is not that much more so I just go for 0.75" thick. I suppose others may have different reasons.

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Alsatian
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Post by Alsatian » Thu Jan 22, 2004 10:13 pm

Thanks Gilbert.


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