Simplistic NJFET RIAA

I have now made a rather ugly box for the riia to be shielded when I mount it in the turntable. Problem is that I have grounded and placed it so its really quiet already. And I got an ortofon rondo bronze. So I´m spending too much spare time buying records and listening. Shame. :)

This riia is properly good!
 
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Once more the effect of cap bypassing in the output of v12r shunt.

Just finished finetuning a new v12r build for a folded cascode and I can report that a small value SM or styroflex bypassing the output zobel cap can be determinant in the final sound presentation.

I am using a 4u7 cap in the zobel and bypassing it with 100pF styroflex can enhance high frequency perception (bigger soundstage presentation, better delineation in the bass)

I found 100pF to be slightly too much (splashy sound in drum metals) so I reduced it to 22pF.... Quite a good blend.
 
You would not be able to have another core type so close in same box with such low harmonic noise. There is some residual but its low. Just let us know if all went well in the listening. Play some of your loud records too.

Turns out I'm worried too much on noise, on my 90dB speaker heard only familiar noise from Aikido pre amp he he.

First impressions with Diana Krall's the very best, less constrained than opamp pre (finally..), some 30cm wider & taller staging, improvement in depth as well. More weight on her voice. Need to solve, speed (Frim fram sauce..), bit more emphasis on details, and I think heard some clipping ;(.

in all very worthy build, another smiling client here Salas, thank you
any tips for improvements appreciated from you guys

best
 
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Congrats. Listen to more records so to make sure if it was clipping or mistracking. If it was clipping, just get a 15+15V 30VA R-Core whenever you can so to wire its secondaries in series restoring to spec 28V B+ and have proper margin for the regulator. When the transformer and box will be final, shorten its wiring to minimum. Otherwise you got quite a small pcb space so to upgrade in interstage and output capacitor quality. If you like the tonal quality now don't touch those anyway.
 
thanks, I did intent to play with output & interstage caps, now using erofoli 4.7uF on output and 0.1uF wima mks. Does the quality on 47nF and 15.33nF matter much? quite a pain finding this value.

I think resistors are good enough. Like your last PTP, I also use philips resistors when I can :), still have 100R shinkoh tantalum, now using salvaged caddock
 
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Changing your 0.1uF MKS interstage to MKP flm & foil like Vishay 1837 keeps small and may prove audible. Quality electrolytics too. But its also about synergistic tonal blend beyond resolution, sometimes lower quality parts can strike a fortunate tone with the rest and the system. If making partial exchanges keep subjective notes so to can revert. Start only after you are well familiar with what you got and its electrolytics have worked to reformation.
 
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-I have finished the PCB corrections with CRT and got the final file.
-The panels for my proto have been drilled for connectors a few days ago.
-I will build it soon so to watch it working in real conditions and maybe trim some value. I expect no problems, but you never know.
-Then I will write a smallest possible build instructions PDF with final notes.
-So it will be ready to be released for GB pretty soon.
 
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-I have finished the PCB corrections with CRT and got the final file.
-The panels for my proto have been drilled for connectors a few days ago.
-I will build it soon so to watch it working in real conditions and maybe trim some value. I expect no problems, but you never know.
-Then I will write a smallest possible build instructions PDF with final notes.
-So it will be ready to be released for GB pretty soon.

:)
 
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