Technics 1210 internal regulation mods

[Paul Hynes]

Hi Martin,

You will hear an improvement with the SR7EHD compared to your SR5. It’s not just the transformer that has been increased in size. The rectification has been altered to a balanced arrangement allowing the transformer secondary to retain it’s ground reference even when the rectifiers are not conducting. The energy storage capacitor bank has been increased and the supply rail for the output stage control circuitry has been improved.

Marco heard a substantial improvement with the SR7 over the SR5. You should hear this upgrade with your power supply even though the internal regulators have been applied. It might not be to the same degree but it will be significant.

Regards
Paul

[MartinT]

Ok, thanks Paul. I'll be coming to you at some point for a price

[Wakefield Turntables]

Ok, thanks Paul. I'll be coming to you at some point for a price

Martin,

Why not go for what I'm getting the SR7EHD-XL! You'll need to speak to Paul with regards to what you get for your money.

PS Paul, now that Martin has installed all these regs can you PM me the price for a complete set??

[synsei]

This thread is a fascinating read chaps and even though much of the technical stuff is beyond my ken, I applaud you all for your dedication and ingenuity. I will continue to follow your adventures with intense interest, especially as I now have an SL1210 to feed

[MartinT]

What these final upgrades have brought to the table builds upon the already excellent sound from the phase 2 split 21V upgrades previously detailed. I had not expected, at this stage, to hear anything much different since there is already a lot of regulation going on and, by inference, noise reduction in the phase 2 mods.

What I immediately noticed were two effects: a lifting and resolving of previously buried detail and, related to this, a further lowering of the noise floor and general hash around the three-dimensional soundstage.

A few examples from my listening: Joan Armatrading (eponymous) starts with Down to Zero, and in there is a buried cymbal. I've always heard it, but now I can hear its shimmer and the way it is struck. Gordon Giltrap's Fear of the Dark sounds superbly detailed and clean despite getting busy in Fast Approaching. The leading edge of his guitar has fantastic attack. In Supertramp's Crime of the Century, Dreamer features an incredibly vivid piano and very front-of-stage voice in a mesmerising spacial presentation. The intro to ZZ Top's Eliminator, Gimme All Your Lovin, features a very dry bass drum with real shape to it. Norah Jones' album Not Too Late features a song, Sinkin' Soon, with her incredibly palpable voice and harmony, as well as gorgeous raspy synth sax (I guess). Yello's Flag features a track, Tied Up, with such a wealth of detail as to assault the senses. Out of this mix come bongos with amazing attack and dynamics.

In my thought experiment about what is going on here, I can only surmise that the impact of these mods, particularly affecting the clocking and pitch regulation circuits, is to feed the motor with an ultra-clean drive waveform lacking in noise components. This would give a reduction in vibration of the motor (even at its low speed) and rotational noise (or pitch micro-imperfections, if you prefer). These are just my ideas and I would entertain any other thoughts on why these particular regulators should make such a difference.

We are into exotic territory here and the mods are not for the faint of heart, although they will present few problems to anyone with electronics experience. Very highly recommended if you want pretty much the best vinyl reproduction you can lay hands on for reasonable money - provided you have performed all the other mods I have so far accumulated, and a system capable of high resolving power.

[synsei]

Martin, what is the total cost of the mods you have fitted please? I'd also be interested to learn how much it would cost to have the work done as they are beyond my capabilities

[Dingdong]

I'd be tempted to have a look at the Vantage Audio mods if I were you Dave. They seem good value to me.
Or just flog it and get an SP-10

[synsei]

I was thinking of a combination of the regs mods represented on this thread and the VA Platter, bearing and feet

[Dingdong]

Personally I'd do the VA feet, bearing and get a good mat for it. Then maybe think about the psu.
Or flog it and get an SP-10

[synsei]

Mark, you wouldn't be wanting me to buy and SP10 by any chance, would you?