Signs of tweakness

Seems I've got it bad with that vinyl bug again. The venerable Systemdek IIX is off for an overhaul, but I'm also considering some cost-effective tweakery. Does anybody have any views or first-hand experiences on the following:

1. Acrylic platters. The Systemdek's is glass, but I've seen a number of claims made for acrylic alternatives. Why should acrylic be any better than glass? And is it better?

2. Mats. The Systemdek is equipped with a floppy felt version, though I've heard tell that silicone/rubber/cork derivatives offer improvements. Again, any good reason why? Do they work as claimed?

3. Record clamps. What useful function, if any, do these serve?

Thanks.

 

Glass tends to ring like a bell ! acrylic is fairly close match to the vinyl, so good energy transfere.

As for tweaks, mass, stability and isolation. Any or all should help. Make certain the TT on a good support DIY or Commercial. The Systemdec has a wood effect plinth, beef it up, brace it and add damping. I did all these to the TD160bc I had many years ago to good effect.

 

"Glass tends to ring like a bell !"

Yep. Put it on Mana.

 

Okay, that makes a kind of sense, even to someone as technically addled as myself.

I prefer Ikea.

Anybody got an opinion to share on mats and clamps?

 

mat - try a ringmat

clamp, as your deck is suspended it may be better to try without, but if you do get one make sure it is a light wieght clamp and not a wieght.

 

But are you going to be banging the platter as it plays? Otherwise surely it won't ring unless something is vibrating at the resonant frequency of the glass, and I presume that the manufacturers all avoid that. In which case the material would make no difference. It strikes me that glass would be good, as it's nice and dense and would therefore have a good flywheel effect. And what energy is there to transfer between platter and record?

 

the vibrations caused by needle in groove will be the transfered energy.
I think

 

If you exite a material, the transmitted vibration will be tinged with the sound of that material, stick your head under water next time you have a bath and hear the difference the change of media makes.

As soon as you play any music that glass disc will start to play along with the music....why do you think they put it on springs ?


As for mana, no matter how many stages you have, it will not eliminate air vibrations from entering the glass platter [that is unless you turn the volume down to zero].....though sometimes I think that how the devil listens.

 

If I say, I don't believe a word of it, would you be surprised? As far as I can see, you're not exciting the material to any noticeable extent (unless you're playing Bach cantatas or something else worthwhile), so there isn't any significant transmitted vibration to go anywhere.

Springs? To isolate it from you bouncing up and down on the floor in time to that lovely Bach of course!

But, I have never disputed with anyone over his religion, so I gracefully (ungracefully? disgracefully?) withdraw from the thread. And I shall take your advice and never take the LP12 into the bath with me.

 

Having said Zanash's explanation made a sort of sense to me, I also have to agree with Tones in that I can't quite see where all this excitement is coming from either (except when a cut of Ornette Coleman is slapped on the deck). The platter is firm and moving steadily, so what energy is being transferred? Where from? The motor? The belt? All the way through the platter (ringing like a bell as it goes) up into the stylus and beyond?

Ach, technical schmechnical. I knew I shouldn't have started.

 

Have IQ's suddenly dropped ?

That lovely sound from the speakers, at 90 to 100db. Where do you think it goes ?

Its absorbed and dissipated through out the room,and all its fitting including the TT. Assuming that in most cases the TT is in the same room often close to the speakers or at least between them. The TT can and I stress can pick the sound waves and create a howl, in the worst case.

Here is a test .....place the stylus in the groove without the TT going round, select phono and turn up the volume now make a sound near the TT you should hear it through the speakers. To loud and you will get a feed back howl. If not tap the plinth this will give you an indication as to the TT ability to dump unwanted vibrations...

 

If you prefer Ikea then it really doesn't matter very much what you do with the platter & clamp ideas.

 

On the subject of tweakery, there have been some items coming up regularly on ebay which have also now been added to HFN's accessory club list:

the information is here.

A motor thrust bearing, a platter damping ring, a motor vibration absorber and bearing damping rings - designed for decks using the std Phillips AC motor (Linns, Regas and Thorens specifically). All four together for a total of £48 sounds not unreasonable.

Anyone had any experience with any of these things? Good stuff or snake oil d'ya think. At least they aren't asking arm and a leg money for these things

 

Zanash,

Thanks for finding the patience to explain. I think I understand now. And I think it means that it's a marginal issue at worst, seeing as I do most of my listening either at moderate to low levels or on the headphones. Therefore I can forget about spending anymore time or money on such tweaks. Oh the relief!

 

OK, just done it.

Clapped loudly beside the cartridge - nothing through the speakers

Did a "Riverdance" impersonation beside the cabinet on which the LP12 sits - ditto

Drummed a tattoo on the plinth - do.

Hmm, I hereby declare (as far as my stuff is concerned) that Zanash is mything in action.

 

Devils advacote hat on here, Tones, you couldn't tell a difference (Or disconcernable one) from the lp 12 and 588 or the mana shelf, so maybe you can't hear a difference in this case. Just a thought oh wise sage, TT's arn't my bag, but unwanted vibrations used to be (in Aircraft), I'm not taking sides here (surprise I know ) just merely an observation. Tones (the yonger)

 

Yes, ol' bean, but this is hearing the difference between noise and no noise, a whole different ball game. If I can't hear this difference, and it really is there, then I am truly going deaf and I shall retire from the forum forthwith and bother nobody any more.

 

Tones
If you couldnt hear anything from that, i have a syringe i can post to you

 

But then, perhaps I just have a very nicely adjusted LP12 (resting, remember, ultimately on a very solid Swiss concrete floor)

 

That almost certainly helps i imagine. You would have to have rather large feet to stamp that floor and make it audible through the system.
But, remember most of us will have wooden floors and so the phenomena is well know and audible to us