Hey,
I've just bought a second hand krell kps20i and i'm looking for some info on this machine as it has a few possible problems.
First, the player makes quite a bit of noise when the disc is spinning, eg not what i'd call quiet anyway.
second is that i seems to produce quite a bit of heat on the left side when running, i guess this is the psu area...
Other thing is the lcd display is not working correctly (time display i think) some of the characters are broken, i guess this is a fault..
Are any of these things (apart from the LCD) "normal" for the kps20i ?
Thanks
Reuben
I've just bought a second hand krell kps20i and i'm looking for some info on this machine as it has a few possible problems.
First, the player makes quite a bit of noise when the disc is spinning, eg not what i'd call quiet anyway.
second is that i seems to produce quite a bit of heat on the left side when running, i guess this is the psu area...
Other thing is the lcd display is not working correctly (time display i think) some of the characters are broken, i guess this is a fault..
Are any of these things (apart from the LCD) "normal" for the kps20i ?
Thanks
Reuben
Yes, mine Krell KPS20i behaves similar with spinning noise and heatdevelopment
The red numerical display has been changed by a green version by Krell says the former owner because of the same problems.
Do you know by any chance what the four AD OP42G right after the DAC section do and the OP27G's further downstream. Thought that the I/V transfer and lowpass filtering where complete discrete in this player.
Do you have the Delta 9 upgrade with the AD 56009F 80 MHz and updated firmeware?
I haven't though.
Greetings!
The red numerical display has been changed by a green version by Krell says the former owner because of the same problems.
Do you know by any chance what the four AD OP42G right after the DAC section do and the OP27G's further downstream. Thought that the I/V transfer and lowpass filtering where complete discrete in this player.
Do you have the Delta 9 upgrade with the AD 56009F 80 MHz and updated firmeware?
I haven't though.
Greetings!
for this Krell model I need a schematic diagram (unfortunately there are no download aera to download the manuals for the older models).
Also for the Krell model "KPS-25sc" (transport "EXU-901a" from JVC inside).
have a look also there:
http://www.diyaudio.com/forums/digi...ch-ct-1-ct1-better-than-vam1254-cdpro2lf.html
Also for the Krell model "KPS-25sc" (transport "EXU-901a" from JVC inside).
have a look also there:
http://www.diyaudio.com/forums/digi...ch-ct-1-ct1-better-than-vam1254-cdpro2lf.html
Attachments
Since the heatsinks for the voltage regulators are bolted directly to the left housing piece, it is very normal for that to be quite warm. The noise may be indicative of the platter motor bearing going bad or simply failing to self-lubricate, which, in my experience, can often be cured by adding a few drops of 'Prolong Super Lubricants Precision Oil', preferrably after taking apart the motor & cleaning the shaft & sleeve bearing(can't recall is this is possible with that version of the CDM-9), if the noise is actually coming from the motor. On rare occassions, noise that follows rotational speed of the disc can be actually coming from the laser's focus actuator, and can be a symptom of the CDM-9 laser getting weak(servo working harder to compensate, creating more actuator hiss).
Krell is even worse than Proceed about releasing schematics(even during the 4 years I worked within a Krell dealership, I never saw a single schematic for anything newer than a KSA-250, even when they had me doing 'special authorisation' warranty repairs), but I have a fair amount of confidence that the opamps in the RIDICULOUSLY long & complicated discrete output stages of this & so many other Krell cd players are simply DC servo's, and don't make a difference to the sound if changed/upgraded. If I actually owned one of these players myself, I'd gut the whole output stage and install the simplest possible output stages, either discrete or OPA134 opamp based. It would have to lift the 'haze' that seems endemic to Krell's cd/dac output stages, not to mention shorten the 24-48 hours it takes them to fully warm up to sound best by quite a lot.
Anyone getting the feeling I'm not a big Krell fan?;-)
Some years ago I made the terrible mistake of taking my, at that time, modestly upgraded(by me) Museatex BiDAT dac & CD-D C-Lock transport to my best friend's house, in order to a/b with his Krell KPS-20i & horribly expensive Krell dac he was running it into. The BiDAT beat his Krell setup so badly that he would not let me leave until he'd gotten to a price I'd accept for the BiDAT, which I've regretted ever since(especially after upgrading further that same dac for him a few years later). He used the KPS-20i as a transport with it for a while, until he discovered how much better the Museatex CD-D(with minor upgrading) sounded as a transport, with it's CDM-2 mech & brilliant Meitner C-Lock reclocking circuit(which is also in the BiDAT, in even better form). Still haven't heard better sound from any digital source than that combo.
Krell is even worse than Proceed about releasing schematics(even during the 4 years I worked within a Krell dealership, I never saw a single schematic for anything newer than a KSA-250, even when they had me doing 'special authorisation' warranty repairs), but I have a fair amount of confidence that the opamps in the RIDICULOUSLY long & complicated discrete output stages of this & so many other Krell cd players are simply DC servo's, and don't make a difference to the sound if changed/upgraded. If I actually owned one of these players myself, I'd gut the whole output stage and install the simplest possible output stages, either discrete or OPA134 opamp based. It would have to lift the 'haze' that seems endemic to Krell's cd/dac output stages, not to mention shorten the 24-48 hours it takes them to fully warm up to sound best by quite a lot.
Anyone getting the feeling I'm not a big Krell fan?;-)
Some years ago I made the terrible mistake of taking my, at that time, modestly upgraded(by me) Museatex BiDAT dac & CD-D C-Lock transport to my best friend's house, in order to a/b with his Krell KPS-20i & horribly expensive Krell dac he was running it into. The BiDAT beat his Krell setup so badly that he would not let me leave until he'd gotten to a price I'd accept for the BiDAT, which I've regretted ever since(especially after upgrading further that same dac for him a few years later). He used the KPS-20i as a transport with it for a while, until he discovered how much better the Museatex CD-D(with minor upgrading) sounded as a transport, with it's CDM-2 mech & brilliant Meitner C-Lock reclocking circuit(which is also in the BiDAT, in even better form). Still haven't heard better sound from any digital source than that combo.
That's correct. Besides the KPS20i I have an old Krell KRS-2 preamp and no way you get schematics or service manuals. I once mailed for some info about the accompiniying KRS-100 & 200, simple facts like weight, size idling power, but they seemed to have forgotten these amps almost completely.
Levinson is exactly the same. Jeff Rowland is much better in that era and Nelson Pass shares his intellectual property for free!
So if your in the market for secondhand highend audiogear, and aren't we all, then remember if you ever get troubles with it, which brands to buy.
I pray that the Philips CDM9 Pro inside my player will last. I perform as few operations like FF REW, skipping, as possible. Don't know if that prolonges the life of it. Maybe some NatLab Philips engineer knows how to pamper/cherish those transports to get the maximum life out of it.
You don't have to worry too much about the laser going bad, since you can scavenge that from ay cdm9 type, but if the platter motor goes irreparably bad, you could be seriously screwed. So, the only thing you can do to extend the life of that motor is to use it as little as possible. Mostly that means simply never letting the thing sit in pause mode for long periods, going to stop mode whenever you'd just pause it. Beyond that, it's pure luck. The VAM1250(1254?) has a suspiciously similar looking brushless platter motor(only nice part I've ever seen on a 12 series), but I doubt it's actually a compatible or adaptable replacement, but haven't had a chance ever to directly compare. Could be the same motor, or completely different.
for description recapping project go to post #352 about
http://www.diyaudio.com/forums/parts/151392-best-electrolytic-capacitors-36.html#post2741758
http://www.diyaudio.com/forums/parts/151392-best-electrolytic-capacitors-36.html#post2741758
Keep in mind that Krell really isn't Krell anymore now that the main man, Dan D'Agostino is gone. Now that the company is run by someone else. the whole way of doing business has changed and often times in such situations. dealing with older products becomes a major pain. where as older products may have been serviced as sort of an customer loyalty thing. the new owners may not feel the same need to deal with aging products. In short they don't feel the same need to oblige customer loyalty. Which is a similar thing to whats happening at the company i work for!
Obviously now it is more easy to get service informations - read the posts #1+2 about
http://www.diyaudio.com/forums/solid-state/199965-krell-fbp-200-a.html#post2775873
Try to get something about the real old stuff like KSA/KMA/KRS/PAM Series.
There's a lot of that old stuff out there that will need servicing.
Same with the Levinson ML Series apart from the ML-2 that's well documented on the Web.
Rowland and Nelson Pass are really great in that era so that should influence your choice when your in the market for some new audio stuff.
I agree. Also Crown, Harman/JBL and Bryston must be mentioned in this case.
From Linn ltd I have heard, that all service informations/schematics are to order there from all models, in which Linn itself do not longer offer/perform a repair service (LK-1 and LK2-80 and Klout are examples).
I will start next time a thread to get a list of all audio brands, who offer both completly and partly service documents and who don't offer any service documents like German Brand Burmester e. g.
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When I was subleasing shop space from a Krell dealer ten years ago, Krell would always give me per-unit authorisation to do warranty repairs when needed, but, even then, would never give up so much as a schematic except some small section needed on one or two occassions for a repair. Even if they were liberal with info, though, I can't think of more than one or two Krell models of anything which I would consider worth owning(and only with upgrading). The first generation amps are the only such things that come to mind.
However, abosolutely the WORST about giving up one shred of service info was Proceed, even now that they are basically a ghost shell company under Harman.
However, abosolutely the WORST about giving up one shred of service info was Proceed, even now that they are basically a ghost shell company under Harman.
I don't understand this term:
"ghost shell company"
Ghost in the Shell:
Ghost in the Shell - Wikipedia, the free encyclopedia
From a Proceed PCD-2 CD Player I have create a comletly schematic (except the transport section, because this comes from Philips) because it was not available about SUN-AUDIO in Germany..
I have posted here anywhere.
Kreel KPS20i has gone dead
My Krell KPS20i has gone dead
I have a spare laser but that did not work either.
Even have a complete spare CDM9-Pro turntable from another much cheapre CD Player but I think the platter on top of the spindle is different.
Krell had that altered probably for it's clamper.
Any suggestions how to proceed?
Can I get the platter of without ruining the brushless motor?
Send some pics soon.
My Krell KPS20i has gone dead
I have a spare laser but that did not work either.
Even have a complete spare CDM9-Pro turntable from another much cheapre CD Player but I think the platter on top of the spindle is different.
Krell had that altered probably for it's clamper.
Any suggestions how to proceed?
Can I get the platter of without ruining the brushless motor?
Send some pics soon.
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If you are not sure the platter motor is bad, that it may be just the laser that's bad, it's not hard at all to transfer the laser from one to the other. If the platter motor is bad(saw that happen exactly once on this mech), then you'd have to either attempt platter transfer(possibly by using a heatgun carefully to make the platter metal expand a bit on the shaft), but it may not be possible without excess risk.
Hi Stephen,
I already swapped the laser but no luck either.
It moved a bit, the old one was completely dead, but it did not read any data.
Is it a correct assumption that when the laser doesn't read any data the motor will not spin?
As I know, you must check follow steps without cd insert after switch on:
1) laser head must move in start position
2) lens must go up and down several times (focus search). While this time laser light must go in "ON" position.
If happen this, insert cd and press start bottom. Either cd starts to rotate (FOK signal is present) or cd don't start to rotate (FOK signal isn't present).
You need actually a flow chart diagram for troubleshooting from the service manual.
As I know, krell haven't his own PCB for the servo board - this must actually be a genuine part from Philips. With help of the equipped ICs of that board below the mechanism - go to the image about
review33.com - ????
it must be an easy task to find out the associated Philips model. Now you can order the service manual for this model.
Independent of this you can contact Mr. d'Agostino for the Krell schemas - check out therefore this thread:
http://www.diyaudio.com/forums/soli...ke-pure-classa-se-despite-low-idle-power.html
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