Vibration Management

[Synaxis]

I had an exciting evening of listening last night. I have been working on my isolation platform design for my preamp these past few weeks experimenting with different materials and honing my fabrication skills. My current iteration of Acacia wood, 1.2" thick and (4) 11 lb/in springs (McMaster-Carr P/N 9434K142) yielded the best bass and second best mid/highs clarity. The Bamboo board I tried had just slightly more mid range clarity. But last night I thought to try some brass cones under the front of my preamp. I left the back feet of the preamp engaged with the platform. Mid range clarity improved and exceeded the performance of the bamboo board. The bass also got better. Then I thought to put my amps on cones. So I lifted the amps onto cones but just high enough to let the rubber feet on the amps still touch their platforms. So almost all of the weight is on the cones but just a little weight remain on the rubber feet. I cannot slip a piece of paper under the rubber feet.

Here's what happened: The bass is like I have never heard it before. The bass is so clear and deep. The mid/highs clarity is splendid. But the most surprising result of all is PRAT. The rhythm and pace of the music went up a notch. It was a night where I could not stop listening to music.

My summary: Isolation of the amp/preamp/DAC is critical. Effective Isolation can be achieved only through the use of springs. My spring isolation platform stops all vibrations coming from the floor that are above 3.2 Hz from reaching the preamp and amps. Elastomers provide needed damping but must be applied with care. Too much damping, as I found with my preamp will smear the mids/vocals. I can build a math model for isolation easy enough but I am not smart enough to build a math model that takes into account the nonlinearities of elastomeric materials. In other words, it is an iterative experimental process- ie. try something and then try something else. And remember, the damping properties of elastomers are not just about the formulation but vary with the load on the elastomers (and shape of the elastomers).

I didn't think the feet on my preamp was smearing the mids (albeit only slightly) until I heard the preamp on brass cones. The same goes for my amps with the bass. It was an important discovery for me.

This is my preamp on the Acacia wood platform supported with a wood base that I painted black. Four springs support the platform and I have two cylindrical rods (Circuit board stops) mounted on the lower board that hold the assembly together when it is not under the preamp and also prevents the top platform from rolling off the springs. I can push laterally on the preamp about 1/8" and then it hits those stops. The two stops are 9" apart to prevent rotation or lateral movement of the top platform. The stops do not touch the top platform unless I push on the preamp.
The DAC remains on the Wellfloat platform.

Awesome update. Thanks for sharing Tony and well done!

 

[viola]

I had an exciting evening of listening last night. I have been working on my isolation platform design for my preamp these past few weeks experimenting with different materials and honing my fabrication skills. My current iteration of Acacia wood, 1.2" thick and (4) 11 lb/in springs (McMaster-Carr P/N 9434K142) yielded the best bass and second best mid/highs clarity. The Bamboo board I tried had just slightly more mid range clarity. But last night I thought to try some brass cones under the front of my preamp. I left the back feet of the preamp engaged with the platform. Mid range clarity improved and exceeded the performance of the bamboo board. The bass also got better. Then I thought to put my amps on cones. So I lifted the amps onto cones but just high enough to let the rubber feet on the amps still touch their platforms. So almost all of the weight is on the cones but just a little weight remain on the rubber feet. I cannot slip a piece of paper under the rubber feet.

Here's what happened: The bass is like I have never heard it before. The bass is so clear and deep. The mid/highs clarity is splendid. But the most surprising result of all is PRAT. The rhythm and pace of the music went up a notch. It was a night where I could not stop listening to music.

My summary: Isolation of the amp/preamp/DAC is critical. Effective Isolation can be achieved only through the use of springs. My spring isolation platform stops all vibrations coming from the floor that are above 3.2 Hz from reaching the preamp and amps. Elastomers provide needed damping but must be applied with care. Too much damping, as I found with my preamp will smear the mids/vocals. I can build a math model for isolation easy enough but I am not smart enough to build a math model that takes into account the nonlinearities of elastomeric materials. In other words, it is an iterative experimental process- ie. try something and then try something else. And remember, the damping properties of elastomers are not just about the formulation but vary with the load on the elastomers (and shape of the elastomers).

I didn't think the feet on my preamp was smearing the mids (albeit only slightly) until I heard the preamp on brass cones. The same goes for my amps with the bass. It was an important discovery for me.

This is my preamp on the Acacia wood platform supported with a wood base that I painted black. Four springs support the platform and I have two cylindrical rods (Circuit board stops) mounted on the lower board that hold the assembly together when it is not under the preamp and also prevents the top platform from rolling off the springs. I can push laterally on the preamp about 1/8" and then it hits those stops. The two stops are 9" apart to prevent rotation or lateral movement of the top platform. The stops do not touch the top platform unless I push on the preamp.
The DAC remains on the Wellfloat platform.
View attachment 136782

With Tony's excellent guidance, I reconfigured two spiked 20mm thick Panzerholz platforms for my Westminster Lab Rei mono blocs into Panzerholz tops suspended by the same 11lb / inch springs that Tony used in his project on top of two spare pieces of 20mm thick high-quality maple plywood. Because the Reis are front heavy, I drilled the four location holes in the bottom plywood to different depths in order to balance the Reis on the Panzerholz top. I don't have the measurement devices that Tony has, but I can tell you that this made a great sound even better -- improvements in depth, speed and clarity of bass and in clarity and resolution of mids and highs, plus an even greater sense of airiness that was already outstanding. Several hours of time in precision-drilling holes with a 3/4" Forstner bit and drill press, routing the edges, sanding the edges, staining them and applying 3 coats of satin polyurethane. Total out-of-pocket cost? About $18 worth of springs and shipping cost from McMaster-Carr. If you or a friend have the basic woodworking tools, making a spring-loaded platform is an inexpensive no-brainer.