The Effect of Damping on Sound: Racks and Turntable Plinths

[analogsa]

I have had multiple 301/401s in the past but never went as far as decoupling the armboard from the motor. Which is perhaps a logical development. The Garrards always sounded a bit darkish in my system so the bamboo may work well there.

 

[remdeck]

I have had multiple 301/401s in the past but never went as far as decoupling the armboard from the motor. Which is perhaps a logical development. The Garrards always sounded a bit darkish in my system so the bamboo may work well there.

Mine was sounding darkish and muffled also in the MPX-monolith.
As of now, build like this, it is really open sounding and intimacy is really stunning. Maybe I'm lucky that it is good now.... Let's see what I think after some months of use

 

[Pallen]

Extreme?

Isodamp between the cartridge and headshell, only other contact points are the plastic washer of the screws. Huge sonic improvement, and easy to verify by tapping the headshell with a metal object, like a screwdriver - very well damped and dull impact, a lot of ringing without the Isodamp. Downside: much harder to set up the cartridge, took me well over an hour.

View attachment 63387

Origin Live in the UK sell a simple product for just this purpose. I read a UK review on it and their comments were very close to Ack's comments above.
This is a fascinating thread.

 

[remdeck]

I've now finished my Garrard 401 plinth, after a lot of experiments.
This is what it looks like:





As you can see I opted for a constrained layer, with bamboo 18mm, aluminium AW7075 5mm, bamboo 18mm, stacked with brass spacers, and separating the armboard from the motorboard. I can just make another armboard if I will change the arm. Thinking about a Groove Master 2, which would look great here.
The turntable has Soundcare Superspikes, which work great, better than normal cones I had and a lot better than damping feet/rubber/sorbothane, and its easy to level the turntable.

A few hours of listening and really enjoying myself and this is where I wanted to go, as the MPX monolith sounded so muffled and flat.
I've compared it to digital and analog is now much better;
The treble is more pleasant and realistic, the mids have a incredible directness and intimacy, spaces are beautifully worked out and the bass has the right drive and definition. And the dynamics are really impressive! This has so much musicality, you are really drawn into the music. I really like it!
When I compare this to my MPX monolith, this is quit something, and it costs not much more.

When our new listening room is ready, I will also change my rack and will give constrained layers a try for the rack also.

Regards, Remco

 

[AnaloginAZ]

Hi Remco,
Thanks for sharing your findings. I am thinking of doing something similar with a Dual turntable. Can you tell me how you joined the constrained layers (e.g. glue)? Also, did you leave the bottom of the 401 open or did you enclose it?

 

[remdeck]

Hi AnologinAZ,

I just glued it together. The upper constrained layer and lower constrained layer are screwed togehter with a long screw from underneath the low layer. The brass bushings are just placed between and are tightend through the long screws.
I left everything open. Just should make soe sort of connection to the powercord, which I haven't done till now. Just don't know how to do this. But its safe from touching!

 

[AnaloginAZ]

Hi AnologinAZ,

I just glued it together. The upper constrained layer and lower constrained layer are screwed togehter with a long screw from underneath the low layer. The brass bushings are just placed between and are tightend through the long screws.
I left everything open. Just should make soe sort of connection to the powercord, which I haven't done till now. Just don't know how to do this. But its safe from touching!

There was some advice in another turntable forum where the recommendation is to leave it open and not enclose it. I just wanted to to know what you did since you like the results. Thanks.

 

[remdeck]

There was some advice in another turntable forum where the recommendation is to leave it open and not enclose it. I just wanted to to know what you did since you like the results. Thanks.

Yes, this is true. As the motor gets quite warm, ventilation is mandatory.
Normally its enough to leave open beneath the motor, or have a lot of space in a plinth (Vinylista comes to mind)
Interested how you get along.

 

[Loheswaran]

Since I think I may be the original instigator here - Remdeck and Peter had asked some questions in my OP "Blond on blonde... On blonde" thread here: https://www.whatsbestforum.com/threads/blonde-on-blonde-on-blonde.30295/

From my experiences in building plinths, a constrained layer approach has worked best for me by far. When I first acquired a Garrard, I tried a stacked birch ply plinth. It was cheap, easy to build and it seemed to be what a lot of people were using at the time (Art Dudley are you out there?)... It worked okay and I loved the sound of this new turntable, in comparison to the VPI Aries I had at the time.

I am a guitar player and something made me start to wonder about using tone woods in a plinth - what works well for a musical instrument seems like it should also work for a plinth, right? I had been reading about the Shindo Garrard and also the plinths from ____ . My next plinth was made from two layers of 2-inch hard maple, with the grain running opposite in each layer - four inches total. If you happen to play guitar (or another instrument that uses maple - mandolin, violin, etc.) you'll know that maple is less warm, more linear, and has a "crisper", more extended top end; as apposed to something like Mahogany which is, generally speaking, warmer sounding. Long story short; the birch ply plinth ended up in the fire pit at a backyard party.

Since this, I have experimented with other tone woods - cherry, ebony, mahogany, and Engleman Spruce. They all sound different and I like them all for different reasons/applications. My experience suggests always using hardwood as apposed to softer woods like pine, soft maple, etc.

At some point I heard about Panzerholz and thought I would try that. I have since found that I really like using it as long as it's "layered" with other materials. In my Technics SP10 Mk.3 plinth I use it more extensively than in my Garrard plinths, because I want the Garrard to be a bit less damped. I also used a 1 inch plate of a aluminum in the SP10.

For the most part, I have built my plinths with a detached/seperate arm pod. I tried to make these arm pods as inert and damped as possible and they are almost 100% panzerholz on the inside. They are capped with either ebony or hard maple.

In my most recent plinth build I incorporated a layer of 2-inch bamboo - I was able to find a really large and thick bamboo cutting board on Amazon. I'm still tuning this 'table but so far I think the bamboo is a winner.

I have also started to experiment more with soapstone. It has some very interesting acoustic properties - much different than slate for instance.

Lot's more I can share and I will also try to post some pics later if anyone is interested.

Not sure about the age or activity on this thread but I read your post with great interest.

I need to plinth 2 DD decks - a TTS 8000 and a TT101 (not as pressing as it has a ql10 plinth).

I successfully made an aerolam plate from aluminium honeycomb and aluminium plate. That was very successful. My intention is to use it as a lower base plate. The rationale being these are used in high end lab microscopes

It’s the top plate that is irritating. I wasted 2 sheets of aluminium plate trying to sandwich some Panzerholz - problem was the press I had use of didn’t apply pressure evenly - a mess putting it neutrally.

I wasted going to pose you this question how do you manage to press layers evenly - have you access to a hydraulic press? Or is it a case of the multi clamp method?

As to plate machining I should be able to access/get use of a Cnc machine.

Have you tried making your own CLD using a similar methodology as Magico? Not being funny but I refuse to spend £14000 on two metal plates and isodamp

 

[vintageaxeman]

The plinth for my CTC301 Classic is a simple flat, open, laminated and pressure treated paper and resin panel. I didn't want to use wood, and it turns out that SME are now using a resin for the plinth material on their new Garrard 310 Advanced turntable. SO I was using a very similar material, which is very dense and therefore very heavy.
I have it resting on five large column feet which are MagLev (Magnetic Levitation) stands, two at the front and three at the back. These were designed and created by Ray Lumley who uses various arrangements of these Maglev units in his various very expensive Lumley Stratosphere turntables. Clearaudio at one point bought the rights to produce these units, although they don't make them nowadays. Mine are the Clearaudio branded ones, and they work very well.
Very happy with the design (it all functions as it should!) and its performance (sounds pretty good to me!).
I have two arms fitted, using an unusual arrangement. but both arms are in geometrically correct alignment with the 301's platter. The 'inner' arm has a few modifications, one being that it can easily be swung to the rear of the 301, so that the second arm can be used.

 

[TooCool4]

vintageaxeman is this a rendered image of what it looks like?