Hi Wellerman,
thank you, much appreciated!
Yeah, well spotted! The electrolytic capcitors are actually not 22uF as suggested, I replaced them with some Elna RFS 47uF - not sure if it sounds ok, that I still have to check. The 47uF were the only ones I could get from Elna and I wanted to go for some good quality capacitors. I was also thinking of having the 22uF electrolytics replaced by some Mundorf or Audyn 10 uF or so polypropylen caps, but they are too big for the PCB, so I left it, but others have done it, as far as I could see from some pictures.
The ones in the PSU are slit-foil BHCs.
Well, I am not sure, whether it's worth it to be so fuzzy about the capacitors or resistors, as Wayne already stated in the manual, but it's good fun to do some "modding". Probably the quality of the circuit and matching of the active components are much more important, but I keep you posted, if it sounds alright.
I was wondering if anybody is using Tantalum capacitors at all in the Pearl? Apparently they had their qualities in e.g. Naim audio gear.
Cheers
Poli
thank you, much appreciated!
Yeah, well spotted! The electrolytic capcitors are actually not 22uF as suggested, I replaced them with some Elna RFS 47uF - not sure if it sounds ok, that I still have to check. The 47uF were the only ones I could get from Elna and I wanted to go for some good quality capacitors. I was also thinking of having the 22uF electrolytics replaced by some Mundorf or Audyn 10 uF or so polypropylen caps, but they are too big for the PCB, so I left it, but others have done it, as far as I could see from some pictures.
The ones in the PSU are slit-foil BHCs.
Well, I am not sure, whether it's worth it to be so fuzzy about the capacitors or resistors, as Wayne already stated in the manual, but it's good fun to do some "modding". Probably the quality of the circuit and matching of the active components are much more important, but I keep you posted, if it sounds alright.
I was wondering if anybody is using Tantalum capacitors at all in the Pearl? Apparently they had their qualities in e.g. Naim audio gear.
Cheers
Poli
Denon DL110 or Ortofon X3MC might be priced more reasonably. Still, not available at Home Depot I guess 🙂 But, all in all this started as a project for the education of your daughter, didn't it? Which parent doesn't want their kid to have the best? Your wife couldn't disagree... 😀
The Elna Silmic II's are actually dirt cheap if you get them at Digikey. Problem is they only send for free on orders over 65 euro. I got a few spares for just in case...
My daughter is 9. Eschews technology, loves Classical music. Near mint classical pressings are cheap and I have been buying her plenty. Nothing better than the family sitting around the fireplace, playing records and reading books on frosty evening. It was my wife that said the 30 year old Yamaha TT was not nice enough for the Living Room! She is supportive, just not as crazy about it.
I swapped out Q1 and Q3 last night and now one channel works. The other channel has no sound, just a load hum. Based on the feedback from other, I suspect that Q2 (ZVP3310) is something to look at as well as the Q10 and Q11 (ZTX450).
Also, the voltages around Q3 on both channels are low - ~ 6 V where Wayne show 10, 10.1, 9.4 v.. See my measurements in the attached. All the resistor values check out. Anyone have any thoughts?
Also, the voltages around Q3 on both channels are low - ~ 6 V where Wayne show 10, 10.1, 9.4 v.. See my measurements in the attached. All the resistor values check out. Anyone have any thoughts?
Attachments
The value of R10 and voltages around Q3 can differ depending on the Idss of your particular quad. According to a post earlier in this thread you should aim for Vc > Vb > Ve on Q3. I had to lower R10 to 4K7 to achieve this and my voltages are now: Vc 6.3/6.1 Vb 5.9/5.9 Ve 5.3/5.3. So I wouldn't worry too much about those voltages, they are the only ones in my Pearl differing significantly from what Wayne got.
What clued you that ZVP3310 was bad? Did you measure ~ 10 mA current going into per Wayne's voltages diagram?
I used 10R instead of 10K on R7, R8 and R10. I think I get carried away stuffing all the 10Rs. After replacing them, found out that Q1 and Q3 were bad. Waiting for an order of ZTX450s.I only ordered 10.
Yikes that means you essentially had 'shorts':
The 24V reg putting 24V into 1.5k in parallel with ?!?
Q1 and a 20V short ...
😱
Replace all active devices at the same time: 24V reg, Q1, Q3 ...
For trouble-shooting purposes, you may wish to isolate the 1st stage: pull P1/R6, Q2, Q5 (and replace Q2, Q5 all at the same time, later)
Let hope the precious JFETs are ok! Yesssssss, my preccccccioussssssss!
PS You'll notice that this isn't the test-each-part sort of troubleshooting but a functional unit, shotgun approach! It ... gets the job done faster!
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Thanks Wellerman for the information. I will not sweat it.
AudoLapDance - Thanks for the information. Probably good idea to replace all active devices outside of the precious JFets. Perhaps Q1, Q3 blew, shielding the JFets from any excess voltage? Not sure I see a need to replace regulators. Everything seems OK on power rails.
I will work on it later - local Audio swap meet today with a bunch of locals from DIYAudio and AudioKarma. There should be a Pass room - bringing my F5.
New England Winter Frankenfest February 23rd Clinton MA - AudioKarma.org Home Audio Stereo Discussion Forums
AudoLapDance - Thanks for the information. Probably good idea to replace all active devices outside of the precious JFets. Perhaps Q1, Q3 blew, shielding the JFets from any excess voltage? Not sure I see a need to replace regulators. Everything seems OK on power rails.
I will work on it later - local Audio swap meet today with a bunch of locals from DIYAudio and AudioKarma. There should be a Pass room - bringing my F5.
New England Winter Frankenfest February 23rd Clinton MA - AudioKarma.org Home Audio Stereo Discussion Forums
Also, if I isolate the first stage, what excactly would I test? Everything powered up is in the ballpark of Wayne's values on his schematic.
Have I offended someone here ?
I have been trying to get some help for a while ,but no one seems to have the time to acknowledge my posts .
I started this project 18 months ago ( I was recovering from a bi-lateral hip replacement ) then I found out I needed to have some chemotherapy . I have another 12 weeks of that treatment and thought I'd try and get this thing sorted out and cheer myself up.
I came here to learn , to ask questions and to answer any I felt I could answer I could with my very limited experience . I realise that you don't make friends of any depth here , but I did expect to be treated as I treat others -with kindness and respect . I guess this is the state of the world now .
Thank you .
I have been trying to get some help for a while ,but no one seems to have the time to acknowledge my posts .
I started this project 18 months ago ( I was recovering from a bi-lateral hip replacement ) then I found out I needed to have some chemotherapy . I have another 12 weeks of that treatment and thought I'd try and get this thing sorted out and cheer myself up.
I came here to learn , to ask questions and to answer any I felt I could answer I could with my very limited experience . I realise that you don't make friends of any depth here , but I did expect to be treated as I treat others -with kindness and respect . I guess this is the state of the world now .
Thank you .
Thanks Zen ,
sorry to come over the way I did ,but the medication gets me down somedays ... just trying to keep my head .
" Ok , I changed out the ZVP and the ZTX and I still have distortion. It only happens when the balance control is all the way to left ...
Please , any way I can track this down ? "
thanks , Rich
PS,
with the balance all the way to the left I get distorted sound from the left side plus distorted sound from the right side ,but at lower volume .
sorry to come over the way I did ,but the medication gets me down somedays ... just trying to keep my head .
" Ok , I changed out the ZVP and the ZTX and I still have distortion. It only happens when the balance control is all the way to left ...
Please , any way I can track this down ? "
thanks , Rich
PS,
with the balance all the way to the left I get distorted sound from the left side plus distorted sound from the right side ,but at lower volume .
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give me link to original post , where situation is more explained - what cartridge you're using etc.
Rich - you talk about a balance control. Where? On what device? Your pearl doesn't have a balance, does it?
It makes me wonder if the problem isn't the Pearl. (although it certainly could be...) Can you describe how and what you have connected from the cartridge all the way to the speakers?
Do you have good sound with the balance in the center? Just trying to figure things out...
It makes me wonder if the problem isn't the Pearl. (although it certainly could be...) Can you describe how and what you have connected from the cartridge all the way to the speakers?
Do you have good sound with the balance in the center? Just trying to figure things out...
rich - I just re-read conversation from 1809
you stopped giving informations and replying on questions , so no use on blaming other Pearlmaniacs (which I'm not , btw.)
whatever - listen to just one channel - use just one RCA cable to Pearl , just one Pearl channel , connected to just one preamp channel
if distortion is there , connect other RCA from TT instead
if distortion is still there - then reconnect other Pearl channel instead and compare
if distortion still persist - you have problems in both channels of Pearl
if not - then you have good starting position for measurement compare of good and bad channel
now let us know , hopefully in efficient way ;
it's important to try exactly what some of us will tell you to do , and come back with answers for that
you stopped giving informations and replying on questions , so no use on blaming other Pearlmaniacs (which I'm not , btw.)
whatever - listen to just one channel - use just one RCA cable to Pearl , just one Pearl channel , connected to just one preamp channel
if distortion is there , connect other RCA from TT instead
if distortion is still there - then reconnect other Pearl channel instead and compare
if distortion still persist - you have problems in both channels of Pearl
if not - then you have good starting position for measurement compare of good and bad channel
now let us know , hopefully in efficient way ;
it's important to try exactly what some of us will tell you to do , and come back with answers for that
... Signal chain , 1200 , orofon cartridge , pearl ,bryston , aleph 30 , speakers .
Ok , tried Zen's suggestion .
R in and R out , then tried L in L out . No distortion on either channel .
I have the Dac plugged into the CD on pre , just tried the Pearl into that input and same distortion . I don't have distortion on the Dac .
Balance is on the Pre . Sound is good when balance is at 12 o'clock.
Ok , tried Zen's suggestion .
R in and R out , then tried L in L out . No distortion on either channel .
I have the Dac plugged into the CD on pre , just tried the Pearl into that input and same distortion . I don't have distortion on the Dac .
Balance is on the Pre . Sound is good when balance is at 12 o'clock.
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so conclusion is ?
you're not having distortion in any case when connecting/using just one Pearl channel , but you're having distortion when both Pearl channels are connected/used ?
edit : which Bryston pre ? is there possibility that Pearl is oveloading Bryston , especially if balance is laid in manner that both channel's input is somewhat attenuated when balance is in mid position ........ so , when you put balance control in either max , input signal is least attenuated .....
you're not having distortion in any case when connecting/using just one Pearl channel , but you're having distortion when both Pearl channels are connected/used ?
edit : which Bryston pre ? is there possibility that Pearl is oveloading Bryston , especially if balance is laid in manner that both channel's input is somewhat attenuated when balance is in mid position ........ so , when you put balance control in either max , input signal is least attenuated .....
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Bryston 4 .
would the distortion be on both channels if it was overload issue ?
I can't hear distortion with the Balance at 12 - only when its full to the left . I don't have a scope to see it .
I only have distortion on one channel with both channels connected .
would the distortion be on both channels if it was overload issue ?
I can't hear distortion with the Balance at 12 - only when its full to the left . I don't have a scope to see it .
I only have distortion on one channel with both channels connected .
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