Simplistic NJFET RIAA

Member
Joined 2009
Paid Member
This one is the best reg V1.2R up to +45Vout maximum changing the trimmer R12 for 500R for +45Vout for minus voltage you can use trimmer R12 1K as like the schematic

Salas shunt reg V1.2R.gif
 
Last edited:
Hi,
and thanks for all those ideas.

I´ll first order some 15nF Caps and measure them to find a pair at exact 15nF.

Then i´ll try the new regulator. Any recommendations on selected bjt´s?
What hfe and what idss at the 2sk170 ?

Did you stick with Pana FC at C2 position?

Greetings Ulf

P.S. Will i need a bigger heatsink for 1.2r or will my copperplate
5mm*135mm*210mm be enough?
 
Member
Joined 2009
Paid Member
Hi,
and thanks for all those ideas.

I´ll first order some 15nF caps and measure them to find a pair at exact 15nF.

Then i´ll try the new regulator. Any recommendations on selected bjt´s?
What hfe and what idss at the 2sk170 ?

Did you stick with Pana FC at C2 position?

Greetings Ulf

P.S. Will i need a bigger heatsink for 1.2r or will my copperplate
5mm*135mm*210mm be enough?

You can buy 15nF & 47nF for RIAA teflon film & aluminum foil here:

Surplus USA Film Capacitors Teflon Polycarbonate Polyester Polypropylene

Ask Mark matched pairs for RIAA e-mail:marko@33audio.com

About mosfets & semis use exact as per schematics don't need any kind of selection hfe & Idss.

Yes C2 Pana FC 63V because Salas designed with it.

About heatsink I'm using one for each mosfet like this:

Digi-Key - HS276-ND (Manufacturer - 529802B00000)

Cheers

Felipe
 
diyAudio Chief Moderator
Joined 2002
Paid Member
Hi Salas,
well thats really funny to read because my sense while listening was
opposite to yours concerning the sound of wimas (well my experience
with cap-comparison where at my friends system). Wimas where
allways the ones with open more fluent and detailed sound. I never
thought that there must be so much of synergy within the system.....
By the way, what are your system components you compared the caps
with? My friend system is Audioplan contrast (heavily moddified), LA-
audio pushpull 6550, and LA audio pre-clone with e83cc. DAC is PSaudio.

Greetings Ulf

My system is DIY. DCB1 was driving my KT88 triode amp (own design), either from my NJFET phono or my Benchmark DAC1 (upgraded for internal signal caps) during those cap tests. Was listening comparing to DC coupling and each cap type by changing outputs. Bird on a wire track from famous blue raincoat. I wanted to use my FKP1 blue caps in a build that is why I set up some comparison to decide over stuff I had stashed, wasn't prejudiced against. But I got underwhelmed. That is just anecdotal experience since you asked, don't get affected. If it works for you with Wima, no worries. Just bypass those output Wima with FT2, to see if it changes anything to your better liking, just for fun.
 
Hi Salas,

okay, ill do the bypass and then listen. On the other hand, i found a pair of
those green russian pios in my box, I could try these as well. Unfortunately
they are quite big and i really tried to keep everything close on my pcb.

@ all anyone has some ideas how to arrange the v1.2r ptp on solderstripboard
to get maximum performance and no oscillation ?

Gruss Ulf
 
You may recall I had some problems with resonance and brightness with my boozhoundlabs/Le Pacific phono preamp. While constructing one for an audio club member I realised, in mine, I had used the equiv. of a 0.0034uf cap where a 0.034 cap should be.

Once the paid job is finished and tested I will replace the errant caps. Here is Martin's build so far.
 

Attachments

  • BHMDppSS.jpg
    BHMDppSS.jpg
    135.2 KB · Views: 393
  • BHMDppUnderSS.jpg
    BHMDppUnderSS.jpg
    127.2 KB · Views: 385
  • BHMDppFrontSS.jpg
    BHMDppFrontSS.jpg
    82.9 KB · Views: 388
  • BHMDppRearSS.jpg
    BHMDppRearSS.jpg
    88.5 KB · Views: 367
Old resistors

It's been a while since I posted here, been lurking, though! I ran my Salas for a while, but ran out of time to play with it. Needs some serious updating; much has progressed here since 2008.

Just wondering if anyone has used old-school wire-wound precision resistors. Are they suitable for my Salas phono stage? Shallcross, IRC, etc. I've got a box full. Pic attached.

Fly not a resistive element! :D

-Kent
 

Attachments

  • old_ww_res.jpg
    old_ww_res.jpg
    105.3 KB · Views: 295
diyAudio Chief Moderator
Joined 2002
Paid Member
I don't remember anyone reporting about having used such parts. If some are wound in a non inductive manner and you can tackle the layout nicely due to their bulk considerations, why not. The cart load resistor and the series in Riaa filter one are the most detectable, you may try on those even on your existing phono and decide if they are doing something positive.