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Strosek
07-09-2010, 19:06
Hi, I'm just wondering if anyone knows exactly what the optimum values are for c210 & R208 for the motor dynamics mod. My scope is down at the moment and I have no way to test for precise values.

I had seen the information posted online but I can't seem to find it for the life of me!

I've done lots of DIYing on the Technics 1200 boards over the years and this is only thing I haven't tried.

Any help would be greatly appreciated and if for whatever reason you don't want these values to be public domain a PM would do the trick!


Thanks!

DSJR
07-09-2010, 20:18
A PM to Dave Cawley is probably your best option, together with looking at the Timestep site, as Dave has actually measured certain parameters of this motor and has considered the supply regulator, which seems to be the main bottleneck in today's thinking...

Strosek
07-09-2010, 20:32
Dave Cawley has exactly the information I need to know the only problem is that this is something he sells so I'm not sure he'd take too kindly to just giving this information out freely.

If he does GREAT, if not I must admit I understand...

colinB
07-09-2010, 21:47
I believe he once wrote here that he was happy to give away the mod to AOS members.

Strosek
08-09-2010, 02:50
If that's the case that's fantastic! I'll wait a bit to see if he wants to contribute to this thread if not I'll PM him in a few days.

Thanks!

Dave Cawley
18-09-2010, 21:30
Hi Dan

If you still need this information, please ask in my forum at www.time-step.net and I will answer in full, with values for you.

Regards

Dave

Marco
18-09-2010, 22:24
Hi Dave,

I think you should answer in full here with values, since that's where the info was sought...

We don't mind supporting your site, mate, and indeed do so, but poaching our members rather blatantly like that is just a little bit naughty! ;)

Fair's fair, so please answer Dan's query here, as the information will also be of benefit to others. He can then visit your site later if he so wishes.

Cheers! :cool:

Marco.

leo
18-09-2010, 23:12
Yes, please share here ! I've got some other stuff I'll be trying in the Technics soon, I'll post details when started :)

Strosek
19-09-2010, 01:31
Did I inadvertently open a can of worms? If I did it was not my intention... I had asked the question directly by PM and was told it would be posted in my thread for the benefit of the group and now we're going to another web site?

I'm I missing something because I admit I'm confused?

I'll wait for Dave to read your responses and clear things up.

Thanks!

Dave Cawley
19-09-2010, 07:41
Hi Guys

When I reveal the answer to the question, it will bring up all sorts of interesting issues. I started www.time-step.net to address this sort of thing. There I have security and comfort.

I'm not poaching, simply suggesting asking the question in a more appropriate forum, one that is objective and technical as well as subjective.

I have finally started to definitively measure the various mods, all of them, for the SL-1200 and also the SP-10.

I hope this makes sense?

Regards

Dave

dale kid
19-09-2010, 10:02
When I reveal the answer to the question, it will bring up all sorts of interesting issues. I started www.time-step.net to address this sort of thing. There I have security and comfort.


Would this be safe in the security and comfort of your own domain free to censor and delete posts?

I'm sorry but there is so much ill informed hot air bandied around about these direct drives and fanciful modifications that after a lifetime of involvement with them it jars a nerve and stupidly I feel compelled to pass an opinion. I really should know better.

Simple RC time constant circuits are not rocket science and why not just answer the question in a straight forward manner?

The original question concerning this so called motor dynamic mod should really ask "why?"

Why alter the RC time constant of this particular part of the circuit?

Forget about the influence this will have on other motor circuit parameters.

May your days be long and peaceful, Dale

DSJR
19-09-2010, 10:55
Dale, I think you'd agree that there are some things that definitely improve the Technics sound quality - mat and isolation and I'm sure that although the bearing, although well up to tens of thousands of hours of rotation, could be subtly improved in tolerances - enough people have stated an improvement. The measurements shown on the Timestep site have confirmed another measured improvement via the regulator mods.

As for everything else, it seems as though the heavy platter came about because audiophile users expected and demanded one - because heavy is better :rolleyes: Personally, I'm stumped that a rubber damped platter (as the Techie supposedly has) still rings... My SL150 platter is rendered pretty dead by the supplied (and alternative Herbies) mat, the main problem overiding everything on mine being the plinth resonances introduced by the lid when fitted to the hinges. remove the lid and the drumming all but disappears. I'll have toi remove the TD125 again and give it another go.

I understand from another poster here that the drive fitted to the SL1200mk2 onwards was very carefully researched by caring engineers for dynamic performance with the supplied platter. I worry that current very expensive "improvements" are trying to turn this motor unit into something that it wasn't designed to be and changing one item for something totally different, such as the platter, is going to need the whole motor being re-calibrated.

I think I'd rather go for an SP10 myself given the money, or even one of those huge old pro turntables and play around restoring them :) better still, I'd buy a NAS Dias with decent tonearm and forget about alternative turntables for the rest of my natural :lol:

Marco
19-09-2010, 11:22
Hi Dave,


When I reveal the answer to the question, it will bring up all sorts of interesting issues. I started www.time-step.net to address this sort of thing. There I have security and comfort.

I'm not poaching, simply suggesting asking the question in a more appropriate forum, one that is objective and technical as well as subjective.

I have finally started to definitively measure the various mods, all of them, for the SL-1200 and also the SP-10.

I hope this makes sense?


Yup, no worries - you can see how it looked, though, from our point of view. It was more how you'd worded it than anything else. I think it would be a good idea for Dan to visit your site to obtain the information he needs.

As there is also interest here in this information, perhaps Dan could then copy and paste the data you give onto this thread for the benefit of the many SL-1200 users on AoS? :)

Marco.

dale kid
19-09-2010, 11:50
Marco. sorry not my intention to cause any discord. Will remove said "strong" remarks forthwith.

May your days be long and peaceful, Dale

Dave Cawley
19-09-2010, 11:50
Hi Marco

Thank you!

For the technical debate, I still think my forum is the better. You monitor it anyway, and cross forum stuff often gets a bit odd, confused and muddled?

You can see why I'm doing this, just read Dale's email again! This isn't the right place to discuss PLL time constants and gain. Trust me !

See you Saturday?

Regards

Dave

dale kid
19-09-2010, 12:24
Dave R, most certainly would agree that there are some areas that may improve the sound quality but all within reason of course and overall design limitations.

The limiting factor as regards any bearing modifications would be due to the chassis interface and no end of band-aid fixes will overcome this.

I shall refrain from comment on so called measurements shown on other websites as my thoughts and opininions may differ somewhat and would apparently appear controversial.

The question of platter damping is fraught with pitfalls. All platters ring regardless when they are struck in open air so to speak. The application of a rubber layer to the underside does not alone contribute to the reduction in (for want of a phrase) "bell harmonics". The calculated damping effect starts to takes over when the platter assembly is placed upon the bearing shaft. The final calculated damping effect comes into play when the motor assembly is incorporated into the chassis.

Changing a component part for the sake of change will of course provide a "different" sound quality. Is that "difference" better or...?

May your days be long and peaceful, Dale

Marco
19-09-2010, 12:44
Hi Dave,


Hi Marco

Thank you!

For the technical debate, I still think my forum is the better. You monitor it anyway, and cross forum stuff often gets a bit odd, confused and muddled?

You can see why I'm doing this, just read Dale's email again! This isn't the right place to discuss PLL time constants and gain. Trust me !

See you Saturday?


No worries. I see where you're coming from. This situation, however, is going to come up now and again, as there are simply too many Techie fans here interested in modifying their T/Ts for them to be shipped over to your place every time they have queries regarding your mods.

I think that on occasions you should answer those queries here, safe in the knowledge that I will moderate any inappropriate remarks, thereby giving you the platform you need to supply the necessary info :)

Yep, see you Saturday. Del and I will be there early doors :cool:

Marco.

Marco
19-09-2010, 12:58
Hi Dale,

Thanks for removing your earlier (rather inappropriate) remarks.


The limiting factor as regards any bearing modifications would be due to the chassis interface and no end of band-aid fixes will overcome this.


Perhaps, but from personal experience, having had the Mike New bearing mod carried out, I can say that it has offered a significant sonic improvement over the stock bearing, giving deeper and tighter bass, a lower noise floor, and thus overall increased information retrieval: in short, a no-brainer.

No doubt the chassis interface limitations prevent the full extent of the sonic benefits of the bearing modification being realised (although Mike has tackled this issue recently), but there is no question that, on balance, there is more to be gained than not by upgrading the stock bearing with one of superior quality.


I shall refrain from comment on so called measurements shown on other websites as my thoughts and opininions may differ somewhat and would apparently appear controversial.


There is no problem with expressing "controversial" opinions, and indeed we would welcome your thoughts and insight, providing it stops short of being personal or inflammatory.


Changing a component part for the sake of change will of course provide a "different" sound quality. Is that "difference" better or...?


Indeed, and the only person who can judge that of course is the listener! :)

Marco.

Dave Cawley
19-09-2010, 13:08
Hi Marco

When they are "technical" and objective measurements, I think my site is the one. After all, it is I who is proving the information.

Nearly every time I come here, someone has a pop at me. That is why I started my own forum. I'm sure you understand deep down old boy!!

Regards

Dave

Marco
19-09-2010, 14:42
It's the nature of the best, mate, as this is a much bigger forum, and thus populated by opinions which won't always necessarily align with your own.

Don't be afraid to express yourself here, though. If anyone unjustifiably 'has a pop' at you, the situation will soon be rectified! :)

Marco.

Strosek
20-09-2010, 02:44
Dave... As per your request I posted my question in your forum.

I'd also like to point out that I was already a member of your forum and have been since July of this year soon after you started it! I go by the same name!

Thanks!

Dave Cawley
20-09-2010, 06:19
HiDan

Good man! I'll answer here:

http://www.time-step.net/showthread.php?137-Motor-Dynamic-Mods

later today.

Regards

Dave

Strosek
21-09-2010, 04:59
Thanks!

I'll look for it and report back once Dave has posted.

:)