VPI SDS Question

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FOUNTAIN

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Lately, I've been upgrading my turntable (VPI Scoutmaster is on the way to replace Scout) and wasn't sure about a certain upgrade. What should I expect if I get a SDS speed controller? If the speed is off just a little and the SDS corrects this, will this make a big sonic difference or unnoticeable? Right now I'm not sure just how off my turntable will be or even how much my Scout was off, but is this why so many people rave about it? Or is there something that I'm missing that the SDS will do that will improve my Scoutmaster? Is it even possible for a turntable to be at the exact speed without one or is speed variation always a factor? Will I need to purchase a strobe light and if so how much are these? Wow. That's alot of questions:D. If someone (Twich54/slowGEEZER!!) has experience with the SDS and could describe what it is like with and without one I would sure appreciate it.

Glen
 
Small speed variations are easily audible with long sustaining notes, like soprano et al, in some turntables, where the fluctuating note is now getting annoying. If the speed variation is egregious, the overall sound just isn't right. Considering that the mains frequency is never flat, speed variations w/o a controller (like the SDS - and I don't know how good this controller is) are almost guaranteed, but also largely damped by the mass of the platter and the motor itself. A good 'table will exhibit very small speed variations.

An easy way to prove speed variations in any 'table is by actually timing a long enough song (or even better, an entire side of the record) with a clear-cut end (does not fade) multiple times, and you shouldn't be surprised if your measurements are several seconds apart. That, of course, would indicate a bad table. The better ones will exhibit smaller fluctuations.

Whether the SDS does the job or not, I don't know, and if it were me, I would seek to have it plugged into an oscilloscope. But I assume it's a power regenerator which simply amplifies a certain frequency (typically 50 to 60Hz) at 120V nominal output, and then the more interesting question is whether the SDS is better than, say, a PS Audio regenerator (which could also, potentially, improve other components)???

I have not owned a VPI, although I will be buying a Scoutmaster as well as it appears, and from what I have read, the rave about the Scout is more about how silent it is rather than how stable its speed is, and I am sure if the latter were egregious someone would have complained about it. Which probably says, don't be surprised if the improvement with the SDS plugged in isn't as large as you'd have hoped for; this, in turn, implies that the Scout or Scoutmaster are stable 'tables. Then again, let's see what you find out...

On a related note, when I touch the Scout's motor I feel the vibrations, and this not a good thing, as they are transmitted to the platter. I am hoping the Scoutmaster's Black Knight motor will be more silent, and am eagerly awaiting your feedback.
 
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Simply put Glen, IMO, it's one of the best upgrades you can make to your VPI.

It provides ROCK SOLID pich / stability, period ! Not to mention, once speed corolations have been established switching from 33 1/3 to 45 rpm is a mere push of a button !

With regards to strobe light question...... not needed, hand held flourescent light (mine is a trouble light purchased from Sears) works perfectly.
 
Spectral and Dave, thank you both for your help. It's good to know that a stobe light won't be needed. Spectral (or anyone else) does one need to have the ability to notice imperfect pitch before they consider an upgrade to a SDS or is this easy for anyone to pick out? As far as what Spectral suggested in listening to a long sustained note, I have not noticed any warble in the music that I can tell. However, sometimes I have to be exposed to what it should sound like and from there it may be very noticeable to me. Dave, how would you describe speed colorations? Is this what spectral was talking about with the annoying fluctuating note or is it entirely something different?

Oh yeah Dave, AWESOME Airies 3. Just love it!!:bowdown:

Glen
 
does one need to have the ability to notice imperfect pitch before they consider an upgrade to a SDS or is this easy for anyone to pick out?

It might be easier to try to get an SDS for eval before purchasing. I personally believe a mains frequency (or voltage, depending on the type of motor) stabilizer is a must for any 'table, especially the less exotic ones.
 
Dave, how would you describe speed colorations?

Actually Glen I said..."corolations", my bad spelling ! should be correlation...meaning difference between 33 1/3 and 45rpm settings.

With respect to speed flucuations , while i was happy with my playback prior to the SDS purchase the benifits of my purchase were easily noticed by putting the strobe disc to the test with and without the use of the SDS. As I stated earlier with it...rock steady; without it , visible (albeit slight) speed variation could be detected. That convinced me !!

FWIW, if buying used $550 - 700 is a fair price.
 
It might be easier to try to get an SDS for eval before purchasing. I personally believe a mains frequency (or voltage, depending on the type of motor) stabilizer is a must for any 'table, especially the less exotic ones.

The only problem with doing an evaluation is that I plan on buying used and not buy from the dealer on this particular piece. But then again if he gets a used one in then I may be able to go that route. It does seem clear though from you and Dave, that this is an essential piece in order to get the best results from my scoutmaster. Thank you.

Glen
 
Actually Glen I said..."corolations", my bad spelling ! should be correlation...meaning difference between 33 1/3 and 45rpm settings.

With respect to speed flucuations , while i was happy with my playback prior to the SDS purchase the benifits of my purchase were easily noticed by putting the strobe disc to the test with and without the use of the SDS. As I stated earlier with it...rock steady; without it , visible (albeit slight) speed variation could be detected. That convinced me !!

FWIW, if buying used $550 - 700 is a fair price.

It seems I can't read either:p. Just to clarify for me, when you refer to testing with a strobe disc and you notice a difference are you saying the difference is what you are seeing or hearing? Or is it both? And thank you for giving me a price range for a used one. I wasn't sure what the normal going price was and now this gives me a ballpark figure to work with. Thanks again.

Glen
 
when you refer to testing with a strobe disc and you notice a difference are you saying the difference is what you are seeing or hearing? Glen

What I saw, thus the audible difference percieved or otherwise ! I suspect if I wanted to go back and forth , ie. ...with and without the SDS in play I would have been able to detect things that I would have otherwise passed on. For me, I'm satisfied in knowing the unit works as intended, thus adding to "peace of mind and a further elevation of my listening pleasure" !

How's that for line of 'chit' !!! Damn I should be in politics !
 
What I saw, thus the audible difference percieved or otherwise ! I suspect if I wanted to go back and forth , ie. ...with and without the SDS in play I would have been able to detect things that I would have otherwise passed on. For me, I'm satisfied in knowing the unit works as intended, thus adding to "peace of mind and a further elevation of my listening pleasure" !

How's that for line of 'chit' !!! Damn I should be in politics !

Thank you Dave for you help.
 
The SDS doesn't just affect pitch. It also helps the motor run quieter and puts out less hash than it's VPI predecessor. And you don't have to manually move the belt to play 45s. I believe it is worth every penny.
 
The SDS doesn't just affect pitch. It also helps the motor run quieter and puts out less hash than it's VPI predecessor. And you don't have to manually move the belt to play 45s. I believe it is worth every penny.

I own an SDS, it is an AC generator much like the PS Audio powerplant, just a smaller version. It definitely puts out less hash then predecessor, for instance my big TNT motor runs a lot cooler with the SDS driving it than plugging the motor straight into the wall or with the old unit.

The SDS is also a big improvement in stability and sound. What surprised me was how bass tightened up. It offers very fine tuning in speed as well, frequency is adjustable to the hundredth of a hertz. This is a no brainer, get one!
 
The SDS doesn't just affect pitch. It also helps the motor run quieter and puts out less hash than it's VPI predecessor.
You mean the PLC ? I have the PLC, and have never been happy with the coarse speed control.
 
Wow! Thanks guys! I was thinking that the SDS was maybe a hit or miss upgrade but with all of the glowing recommendations I just need to get one. Now, anyone want to sell me one for cheap?:D
 
Yes, it's a no brainier between the added convenience and noticible improvement in the sound. Get one and don't look back, that's what I did. If you see one on AudioGon jump on it quick, they don't last long. I tried getting one for several months before I fnally scored.
 
You mean the PLC ? I have the PLC, and have never been happy with the coarse speed control.

Yes, I'm talking about the PLC. Although at the time I purchased the PLC I thought it helped the sound. Substituting the SDS was a real shock!(please pardon the pun)
 
Yes, I'm talking about the PLC. Although at the time I purchased the PLC I thought it helped the sound. Substituting the SDS was a real shock!(please pardon the pun)
I did not have to hear that! Now you have me lusting after an SDS ! It just never ends !!!
 
Well I pulled the trigger today and bought a SDS. It will be at least until tommorow before my dealer finishes up with my table and then I'll get a chance to use this baby!:rocker: The ring and center weight are on their way so I'll have to wait till next week,or longer,:sad: before they arrive. Thank you guys for all of your advice, I can't wait till it's up and running.

Glen
 

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