Sansui P-M90 Turntable User Manual
- Thread starter Vytas
- Start date
Hey wait a minute... this thread is 5 years old and I was so bold as to resurrect it. WTF was I thinking. Oh, I was thinking I just restored one of these tables and would love to get a copy of the User's Manual like the OP requested. So... any help appreciated. Service manuals for this are a dime a dozen all over the place. No UM listed anywhere. Thanks for looking.
Thanks for the heads up. Found it on VE. That's going to work just fine. Looks like it's very similar. Curious what the differences are? I have a few of these type of decks for the novelty and fun aspect of it. That would be programmable both sides play. A couple from Sharp, one vertical one horizontal. They sound decent but as you know they are limited. I do have an issue I still have not been able to resolve. The LP's appear to be warped when played. It's not the LP but when I look at the main drive platter, it appears to be true. When the LP is lifted for play the only thing holding them up is the center "puck" and that only covers the label. I wondered it this lack of support causes it to appear warped.
My best guess, is that yours has a different front panel, and was probably designed so Sansui's shallow components of the era could be stacked on top. Mine exposes less of the record through a more narrow window on top.
About your problem, aren't the LPs being clamped in place securely? On mine there's no such issues, they only look warped if they are in fact warped. Check the clamp mechanism is working properly, if it wasn't, the small platter would cause all sorts of issues. It should be clamped in firmly like a CD. Try checking different records.
One tip, which I learned the hard way. This player is very sensitive to the belt used. If you use a belt which is too loose, the tray loading mechanism isn't reliable. Too tight, and the arms move in notchy increments instead of smoothly, because the servo circuit has to build up enough voltage to make the motor move, under the extra load of the tight belt. The result is it just sits still until it breaks free, then it jumps forward. Some belts listed online for this player are the wrong size. I actually tried four sizes before I was satisfied with how smoothly the arm moves.
I'm curuous how it compares to your Sharp. I kind of wanted a 117 for a while, and was eying ebay, but then I found the Sansui locally. I think the Sansui when it's working correctly sounds really nice, I use mine all the time these days. It's not what you'd call easy to work on though, that's for sure!
Belt used is a SCX4.3, inner circumference of 4.3, height of 0.045, thickness of 0.045. The belt seems to work fine. Is that the same as what you settled on? I am still dialing things in etc. but I think I like the Sharp unit a bit better in overall form. The top is flat and stackable with controls on the front where this, while flat, does need to have the keyboard exposed. However the function of the Sansui is much easier to deal with. Essentially it's two arms on one mechanism vs the Sharp where it's two arms and two mechanisms to deal with. More to come.
I wish I knew - I bought a bunch of belts from a local electronics store, and he never has them labeled. The previous owner of the player was a tech who ordered a belt from one of the common online vendors, and that one caused it to skip periodically on side B. I'm mostly curious about which one sounds better to you - the Sharp has that very nice looking display, but the Sansui is direct drive, which helps it achieve excellent speed stability, signal to noise ratio, and very low wow and flutter considering the lack of platter. I also think the audio technica cartridges the Sansui uses appear to have more promise sound wise than what they Sharp has. The Sansui cartridge bodies appear to be for all intents and purposes identical to the AT-91 body, however the stylus assembly is smaller to accommodate the position sensors. My Sansui has a much smaller exposed portion on top, and is more easily stackable - I believe yours is designed to be the base of a Sansui rack system, where the other components are shallow and cover only the flat part on top of your turntable.
I still get a pleasant surprise when side A of a record ends, and I hear the click of the solenoid to raise the side A tonearm, then the turntable changes direction, the carriage moves, and the side B tonearm clicks as it goes down. I have much better turntables, but the plays both side thing really doesn't get old.
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I think the Sansui sounds better from I can recall of the Sharp sound. More refined. I did replace all the stylii in both units so at least I am not dealing with stylus of unknown use. Agree on W&F. Sharp is belt drive vs the DD of the Sansui. The lack of a real platter though has me bothered and a bit confused. When more than 2/3rds of the LP is not supported you seem to loose some of the benefit of the DD. The arm naturally will tend to move more on the outer grooves vs the inner as it approaches the support of the clamp and motor.
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I think the Sansui tracks sufficiently light, that deflection of the record from arm pressure isn't much of an issue. Main benefit to DD is accurate speed, and low W&F, and I actually find it incredible how well it works considering the lack of platter - I think it's a case of substituting technology for brute force, and Sansui really pulled it off. This turntable is ridiculously complex, and a nightmare to troubleshoot, but when it works, it really does work well. I actually bought my Sansui as a novelty, and after studying how it's supposed to work, and making it work properly, ended up using it more than I use my TD-124 or my Clearaudio. List price for this turntable in 1986 was $500, more than a Technics SL-1200 at that time. I originally wanted the Sharp too, it just looks better - but I don't want to seek one out if it's not going to sound as good as the Sansui, because in reality if that's the case I just won't use it. Actually it's the first time I've ever had any Japanese made turntable in my system for so long.. I've always been into simple European stuff.
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chapps
Well-Known Member
Waking up this thread, and hopefully you guys see it !
I have an Sansui P-L95R that operates just fine. My son swears the pitch is a little flat, so it needs a little speed adjustment.....OK, I said lets look into it.
1. I got the manual and a old non-working unit and took the thing apart as a test. This went good and the mechanism is not so daunting as expected. Getting the motor off is a little scary. Then I got stuck.
2. The manual's method of speed adjustment is just not understandable to me -- I don't get the entire resistor circuit etc. that I need to construct. WTF? I though it would have a pot I could turn with a "strobe disc"., but I have to completely dismantle the motor etc.
3. Is there an easier way ?
4. And what are the reasons the speed would drift on this TT?
Any help appreciated, and I can do something while stuck at home!
I have an Sansui P-L95R that operates just fine. My son swears the pitch is a little flat, so it needs a little speed adjustment.....OK, I said lets look into it.
1. I got the manual and a old non-working unit and took the thing apart as a test. This went good and the mechanism is not so daunting as expected. Getting the motor off is a little scary. Then I got stuck.
2. The manual's method of speed adjustment is just not understandable to me -- I don't get the entire resistor circuit etc. that I need to construct. WTF? I though it would have a pot I could turn with a "strobe disc"., but I have to completely dismantle the motor etc.
3. Is there an easier way ?
4. And what are the reasons the speed would drift on this TT?
Any help appreciated, and I can do something while stuck at home!
Waking up this thread, and hopefully you guys see it !
I have an Sansui P-L95R that operates just fine. My son swears the pitch is a little flat, so it needs a little speed adjustment.....OK, I said lets look into it.
1. I got the manual and a old non-working unit and took the thing apart as a test. This went good and the mechanism is not so daunting as expected. Getting the motor off is a little scary. Then I got stuck.
2. The manual's method of speed adjustment is just not understandable to me -- I don't get the entire resistor circuit etc. that I need to construct. WTF? I though it would have a pot I could turn with a "strobe disc"., but I have to completely dismantle the motor etc.
3. Is there an easier way ?
4. And what are the reasons the speed would drift on this TT?
Any help appreciated, and I can do something while stuck at home!
Nothing about working on the P-L95R is especially easy, but it is great once it works. I was using mine all morning.
Speed drifts due to components drifting as they age, and issues with lubrication. Just stay focused and follow the manual, and I'm sure the result will be good.
chapps
Well-Known Member
@maxhifi Thanks for the reply!
It works fully and every mechanism is OK. It's jsut this slight pitch flatness. There is no 'wowing' in the sound or anything. It's just it sounds like a tad pitch flat right through all LPs. My son's superman ear can tell that, so I need to just check the speed.
The problem is that I don't get the specifics the service manual says (here's the link, if you are inclined!)
(https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwi9356bja_qAhWkmHIEHRzEBbEQFjAAegQIBBAB&url=https://www.vintageshifi.com/repertoire-pdf/pdf/telecharge.php?pdf=Sansui-P-L95R-Service-Manual.pdf&usg=AOvVaw0cdTKpjeEBae-ffshgDMid).
I mean i have to completely free the motor from its mounting -- it would seem unecessary just to get at the pots. These service manuals are written is secret code with relevant steps left out ! How else do I get at the pot?
Yes, I have been utterly shocked how good this player sounds every time I use it. Considering how 'extremophiles' pooh-pooh it because they see it as a contraption.
It works fully and every mechanism is OK. It's jsut this slight pitch flatness. There is no 'wowing' in the sound or anything. It's just it sounds like a tad pitch flat right through all LPs. My son's superman ear can tell that, so I need to just check the speed.
The problem is that I don't get the specifics the service manual says (here's the link, if you are inclined!)
(https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwi9356bja_qAhWkmHIEHRzEBbEQFjAAegQIBBAB&url=https://www.vintageshifi.com/repertoire-pdf/pdf/telecharge.php?pdf=Sansui-P-L95R-Service-Manual.pdf&usg=AOvVaw0cdTKpjeEBae-ffshgDMid).
I mean i have to completely free the motor from its mounting -- it would seem unecessary just to get at the pots. These service manuals are written is secret code with relevant steps left out ! How else do I get at the pot?
Yes, I have been utterly shocked how good this player sounds every time I use it. Considering how 'extremophiles' pooh-pooh it because they see it as a contraption.
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@maxhifi Thanks for the reply!
It works fully and every mechanism is OK. It's jsut this slight pitch flatness. There is no 'wowing' in the sound or anything. It's just it sounds like a tad pitch flat right through all LPs. My son's superman ear can tell that, so I need to just check the speed.
The problem is that I don't get the specifics the service manual says (it is attached if you are so inclined!). I mean i have to completely free the motor from its mounting -- it would seem unecessary just to get at the pots. These service manuals are written is secret code with relevant steps left out ! How else do I get at the pot?
Yes, I have been utterly shocked how good this player sounds every time I use it. Considering how 'extremophiles' pooh-pooh it because they see it as a contraption.
Have you changed the styli yet?
You could at least check speed by printing a strobe disk, attaching it to side A of a record and then and playing side B with the cover open. Then figure out how to tweak the correct pot a bit until the dots freeze.
The note in the manual seems to say that some models have holes in the direct drive motor board to enable adjusting the pots without removing the motor.
chapps
Well-Known Member
Yes, styli were changed first thing and drawer belt changed.
That is an excellent idea about fixing the strobe disc to the LP. However, as far as I have tried, it seems impossible to play an LP or even spin one if the cover and side has been taken off. The modules are all interconnected and the motor cannot be operated if the front/top panel is disconnected. I have to figure out that since the service manual offers no clues on that, or if that is normal.
It sounds excellent as far as reproduction goes, but there is this 'argument' that the speed is just a tad off. Its like the orchestra is playing in a flatter key than expected. So it is a minor thing, but requires major surgery?
That is an excellent idea about fixing the strobe disc to the LP. However, as far as I have tried, it seems impossible to play an LP or even spin one if the cover and side has been taken off. The modules are all interconnected and the motor cannot be operated if the front/top panel is disconnected. I have to figure out that since the service manual offers no clues on that, or if that is normal.
It sounds excellent as far as reproduction goes, but there is this 'argument' that the speed is just a tad off. Its like the orchestra is playing in a flatter key than expected. So it is a minor thing, but requires major surgery?
There is an interlock switch which disables playing with the cover off. Look at figure 4-2 in the manual for how to bypass it.
You motivated me to check mine.
I printed a strobe disc, and taped it to a pristine copy of hall and oates, which I will never listen to.... loaded the record, opened up the player, defeated the interlock. Hit play side B... 33 RPM is locked in perfect, 45 is a tiny bit slow. My motor board has no holes for the speed adjustment, so I'd have to take it completely apart to adjust VR1 and VR2. I'm going to call it good, I seldom use 45. If I did take it apart, I'd consider relocating the trimmers to the back of the board to make any future adjustments easier.
If it sounds flat, it probably is flat. Human hearing is very sensitive to pitch. A slight tweak of the control will be all it takes to fix it, but access is a nightmare in these machines. I guess it's paying the machine back for all the records you haven't had to flip over
chapps
Well-Known Member
Well said!
I just got done! Yay!
Yes, I used a trial and error method - took off the motor adjusted the pot, put it back, checked the speed ...repeat and rinse till the speed is right. Took a few tries but a good probe disc with the +/- 2% and 4% really helps figuring out which direction to turn the pot. Patience and care....
Thanks for holding my morale hand !
Lets see if it is still the same tomorrow. Ha!
I just got done! Yay!
Yes, I used a trial and error method - took off the motor adjusted the pot, put it back, checked the speed ...repeat and rinse till the speed is right. Took a few tries but a good probe disc with the +/- 2% and 4% really helps figuring out which direction to turn the pot. Patience and care....
Thanks for holding my morale hand !
Lets see if it is still the same tomorrow. Ha!
I was wondering if a dental mirror and the tiny flat blade screwdriver which came with my Nagaoka would let me adjust it without taking anything apart.
Glad to hear you got it done- how slow was it?
Hint: if you ever wonder if you're too slow or too fast, touch the moving record.. you will figure out it out by seeing what happens with the dots when you slow it slightly manually.
