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Old 26th March 2009, 10:55 PM   #1481
Salas is offline Salas  Greece
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Will do proper AB now that it got well broken in. Planning in the next few days. Will post.
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Old 26th March 2009, 11:10 PM   #1482
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Quote:
Originally posted by RCruz
When you have time, please comment on the drawing... I must be sure there are now flaws this time.
I think that you got all JFETS facing the wrong way.
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Old 26th March 2009, 11:16 PM   #1483
Salas is offline Salas  Greece
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Unless you actually show the underside in the pdf.
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Old 27th March 2009, 02:26 PM   #1484
RCruz is offline RCruz  Switzerland
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Hi salas

I forgot to tell you this is the underside of the board.

Apart from that issue, do you agree with the overall schematic ?
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Old 27th March 2009, 02:42 PM   #1485
Salas is offline Salas  Greece
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Yes it looks OK. I would make provision for an alternative general earthing point to star at C2 earth node too, just in case. Also try a 1k8 R20 on your current phono to see if it stabilizes easier.
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Old 27th March 2009, 04:19 PM   #1486
RCruz is offline RCruz  Switzerland
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Thank you Salas

Increasing R20 lowers voltage in Q5.... will it affect sound quality ?

What should I expect ?

Should I have more than 1 GND point ? my actual setup has one star gnd where all gnd´s go.
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Old 27th March 2009, 04:29 PM   #1487
Salas is offline Salas  Greece
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I meant to have one point still, but different take off alternatives just in case. Regarding R20 I thought it may help you if there is less voltage across Q5 regarding the noises you get. Since nobody else ever got the noises, I don't know more. Its a proposed experiment. You will tell if it helps the noises you get during warm up or if it changes the sound. The current remains the same.
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Old 27th March 2009, 04:39 PM   #1488
RCruz is offline RCruz  Switzerland
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I believe noises come from bad solder joints... my pcb is now a real mess.... that is why I want to rebuild everything.

If nobody else reported any issues, maybe I should stick to your original design.

Another pertinent question:

I am now using 2K21 RC55Y Welwin 0,1% metal film for cart loading and really think this is the perfect value.

I would like to try Shinkoh in there but do not know if I need to change the value.

I would really apreciate your comment.

Ricardo
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Old 27th March 2009, 05:04 PM   #1489
Salas is offline Salas  Greece
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Normally Shinkoh gives the most grain free and organic rendering there. But not heavy at the same time. I would keep the value. Only thing is that with Shinkoh you can normally go higher in value before you get some ''pinch'' as with other resistors.
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Old 27th March 2009, 06:49 PM   #1490
RCruz is offline RCruz  Switzerland
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Can you please suggest a good quality DMM ?

Myne is able to read capacitances but I always get lower values than indicated in the caps. (For instance, K72-6 0.047u reads 44.6nF)

ERO 620pF reads 599pF....

Mundorf 4.7uF MKP reads 4.4u ...

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