Simplistic NJFET RIAA

diyAudio Chief Moderator
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CMF55 are a good deal at 50ppm among others like Caddock MK132. Watch out how you handle Vishay VAR naked Z-Foils if using any. I managed to kill one just by clipping a crocodile end on one of its "ears" to monitor voltage. Destined for a place in the all jinx hall of fame dead parts museum.:)
 
diyAudio Chief Moderator
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Another useful tip is before pushing the optional mini sinks on the input JFET(s) prepare them collars a bit wider with the pliers and form fit them on another same case transistor or Jfet first. Else the pressure will be too much for already soldered Q1 Q2. The mini-sinks do make a contribution for less difference between cold start open case to hot later closed case states when biasing but those 369s will always be drawing a bit more current as they get working up with self and ambient temperature rise in time. In the HOMC and MM it will be very little play though because there adequate degeneration is affordable in the form of higher value R2s.

And no, I don't prefer to CCS their R13 current feed.:D
 

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The phono is playing for a few days now and couldn' t be happier.
First residual noise is almost non existent and this is important in my setup, as I use high sensitivity horns. Resolution has gone up with no apparent sign of harshness. I can hear things I didn 't before, as the breathing of the musicians in some recordings.
But the biggest difference is the scale of depth, height and panoramic extension of the stereo image, from before. You can easily tell the position of an instrument in the orchestra. Strings are so silky smooth with no sign of grain. Voices also.
Bass has become tighter and more defined.
Music is more effortless and dynamic.
I attach some pictures of the whole setup as the folded simplistic has found his place back on the music system.
Salas, this an excellent effort. I have built many simplistics, but for sure I didn't expect this! Really high end sound, and maybe even more.
The only problem is that my other half not seeing me much lately, and although she is very understanding, she started to complain as I spend most of my time listening:)

EDIT something doesn' t work with attachments, will post later

Arrrg....

Writing stuff like this makes my bathroom refurbishment job even more dull.

need to finish this job and get back to business
 

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diyAudio Chief Moderator
Joined 2002
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Start with the 550 and we see what's the deal. Must give 0.6Vbe. Before that see that no K117 reads as short across its outer pins. Few decades of Ohm is normal. Not open either. About the 9530 I am still bit suspicious giving that Vgs when cold but we will see. Process of elimination...