Damping Tweak for Technics 1210

[Disles1]

I've been reading lots lately about high-end turntables and find that much is made of a well-damped plinth and isolation of the tonearm from the plinth, etc. to reduce/eliminate resonance reaching the stylus.

A few years ago I heard the benefit of Harmonic Resolution Systems damping plates placed on top of equipment so DIYed my own using 1/4" brass (nice looking and heavy) and 1/16" EAR Isodamp. I used these on top of my CD player and preamp.

Today, while listening to records I lowered my stylus onto a stopped LP and tapped the top of the Technics. There was certainly some sound (not loud) from the speakers which I assume came from vibrations of the tapping making their way through the tonearm - a modified Technics - to the stylus. Knowing that the tonearm assembly is connected directly to the top plate I assume that this is how vibration is transmitted.

In any case I placed a 4" square DIY-damping plate behind the pitch control slider overlapping the tonearm base. It's thin enough that it doesn't impede tonearm movement. When I tapped again there was no noise from the speakers.

I think there was a lower noise floor when playing Eric Clapton's Unplugged album and a bit more clarity. I would be interested if anyone else tries this and what you find? In any case, the tweak is cheap, reversible and non-damaging.

[Marco]

Hi Ken,

Thanks for the tip. I've moved it to Strokes of Genius, as this is where all good ideas like this go :)

Could we have some pictures, please, of the damping plates you're discribing, and also them placed in situ on your T/T?

Cheers! :cool:

Marco.

[sq225917]

So no vibration getting through the plinth to the bearing and into the platter?

[Disles1]

Hi Simon, I don't know if "no vibration" is getting through but tapping on the plinth reveals little or no noise through the speakers. I'm assuming that the plinth is better damped than previously. EAR Isodamp is wonderful for constrained layer damping.

Per Marco's suggestion I've attached a photo of my DIY damper plate. The HRS plates are aluminum; I used brass because it was available (and looked pretty). As well, I had made mine square for a previous purpose, while I'm sure a better shape could be made for the Technics if wanted.

[sq225917]

Could be a nice little tweak... ;-)

[jandl100]

Shame about the looks! - could you put it inside the chassis?

[MartinT]

I guess you could paint it black? I'll have a play with this idea, see if that part of the chassis is particularly prone to picking up vibes. The Isonoe feet do a great job of isolating the deck as a whole, but I think you're pointing to something different here.