Simplistic NJFET RIAA

Jump to Latest
#2,921
RCruz said:
Remenber the cap over the voltage reference in the shunt must be very well chosen...

Ricardo
Click to expand...

At shunt do you refer to C4 220uF/63V? If yes I chose Panasonic FC because I can not get Silmic II at this voltage range.

The rest of caps for shunt are:
C1 100uF/25V Silmic II
C2 1.000uF/63V Panasonic FC

I have several BG in other diy projects that now I am not using, if the Simplistic sounds good I will try to change (for example I am sure that I have 2 BG 10.000uF/63V for PS instead the Sikorels🙂)
 
#2,923
150912d1261314425-simplistic-njfet-riaa-45vshunt.gif
 
#2,924
In this case, C2 determines the Tone so you will hear his cap above all. (Muse produces big bass but needs a film bypass - Silmic are quite good )

IMO C1 removes harsness and I noticed big improvements in low level detail by upgrading to 220u 35v Ruby ZA (Inexpensive and VERY efective at high freq).

C4 must be transparent so I am using dedicated nonpolars here... unfortunately these are only 35V so I guess you could use ZA also. 🙂
 
#2,925
Thks for advice, the big problem here is the high voltage needed for C2 & C4, I have 4 caps 220uF/100V Nichicon Muse, do you mind will be better for C1 & C4 instead the Silmic II? I believe wil lbe better the Silmic II except for C1 is only 25V & the Nichicon is 100V here the difference is big but for C4 the Silmic II is 63V & the Nichicon is 100V there is not a lot of difference & don't believe better sound changing to Nichicon, what do you mind?
 
#2,935
trimmer caps for RIAA

Hi everybody,

I am looking for good trimmer caps for RIAA, mine preferences are PTFE film or Air dielectric (but air dielectric is very expensive & only can get till 30pF max. so I can not buy them), due to the fact the russians mica are 15.720pF 0,3% tol. & the mica Pcx are 330pF 5% tol. results a total tolerance maximum of 63,66pf so I suppose that I need something like this:

1st option teflon PTFE "the best" after air
5-60pF 250V PTFE film Vishay 3€612 each (minimum order 5)
Vishay | Pasivos | Condensadores | Condensadores Variables (Trimmers) | PTFE Film |MCO228180908003
RF166999-01.jpg


2nd option polypropylene PP
Digikey only PP 4,5-65pF 100V Sprague-Goodman 1€15 each (minimum order 1)
Digi-Key - SG3009-ND (Manufacturer - GYC65000)
An externally hosted image should be here but it was not working when we last tested it.


More comments will welcome.
 
Last edited:
#2,939
IMO Pana is quite honest sounding and if you use 1000u, you will not loose bass.

I got a lot of 1000u 100v Super Through... I will try those and report the results 🙂

As for the trimmers I guess the max value is 7/150pF PTFE... not enough for the 16n... You will need a third cap (220p smica maybe).

I would try a fixed 330p mica and compare with a 390p mica // CCCP silver mica 15,72nF

Ricardo
 
You must log in or register to reply here.
Top Bottom