Simplistic NJFET RIAA

Tough luck... Only one out of 50 drops within the required range for Q1 and Q2.... Sigh....

Could you please have a look at the values I got and advise how should I proceed? Should I get more or could we work something out with those values?

7,22
8,47
8,76
8,95
9,01
9,21
9,4
9,44
9,49
9,49
9,52
9,68
9,68
9,72
9,72
9,76
9,77
9,8
9,8
9,81
9,91
9,92
10,04
10,05
10,1
10,15
10,2
10,21
10,3
10,3
10,3
10,32
10,33
10,34
10,4
10,42
10,42
10,45
10,48
10,49
10,52
10,62
10,64
10,67
10,75
10,76
10,8
10,93
11,04
11,12

Thanks again
 
diyAudio Chief Moderator
Joined 2002
Paid Member
It was not far off to set from the PDF one. Use your 10.3 ones for Q1s on each channel, the 10.32-34 ones for Q2s, 10.04-05 for Q4s, 9.4-9.44 for Q5s. Good luck.
 

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WOW that was super fast. Thanks a lot again :)

I have gone through mouser to find some suitable components. I basically chose from Vishay Metal Foils and Kamaya carbon composition (both where available), vishay polypropylene for RIAA and Cornell Dubilier polypropylene for output.

It is not meant as a fancy all-out build, but rather a decent one to give me an insight on how the circuit sounds and behaves.

Could you please have a look at my list in case you have any suggestions? thanks

https://gr.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=fb07ee4144

Dimitri
 
My preamp is in getting some new aluminium cloths :)

I'm waiting for a toroidal transformer also a very nice power switch/button to be installed in the front of the case.

Despite buying some Mundorf Mcap 0,1 for interstage coupling i didnt liked so i used some NOS ERO Mkp1845 0.047uf wich sounded more balanced. Also i changed the 15nf capacitors in RIAA to NOS Ero kp1830 (MKP1837).
I will change also the resistors in RIAA network with some more precisee ones as i'm preparing a bigger order to Farnell next week.

By the way wich resistors to order to Farnell, carbon film, metal film ?
 

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Would you use any bypass cap with the obbligato MKP oil caps? Does the teflon 0.22uF FT-3 caps used as bypass cap be a to high value used with a 2uF cap?
I am truly sorry that matching is not my strong side. :-( Because of this lack of knowledge I feel I have to ask some silly questions, but my eagernes to listen, read and learn is very strong. :)

With the kindest regards

Martin