Simplistic NJFET RIAA

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-Very good turntable system indeed, the Spacedeck. Is the arm a current Helius?

-Interesting and many diy experiments I see in your photo link. Bravo.
Why is the AGV for? Don't tell me that you ride an Italian Desmo with a dry clutch...goes well with no feedback and full range attitude.:cool:
 
thanks Salas too good!

my space is old ,arm is mentor

modest yamaha szr660 but go down very well ;)

after 20 year of bassreflex I tray FR ,supravox sound very well and openbaffle have incredible space info, not much bass but clean ,scanspeak have more grit but ........

I suggestion to try OB ,there are a good cheap for explore wolks-ob
 
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...Don't drag me in to speakers, its going to be OT hell!:devilr:

Because speakers are my love and specialty...

OK, just a little OT... You very well love OB detail and space and freedom for 2 reasons mainly: 1st critical msec of reproduction is free from box congestion, figure of 8 pattern is a means of controlled dispersion, i.e. less room coloration.

...Back to Salas RIAA.

After checking the Steve Bench cascode diy tube unit for preferred matched tubes, best stabilized PSU, best step up choice (gutted the Dyna DV6Z and put it inside the Bench so to avoid RCAs and cables), fine tuned its riaa eq etc. and did some comparisons with the Salas, I can confidently say that the only difference is the JFET characteristic VS the tube one. Just some less interest in music interplay, and a somewhat tamer tone. Of course if you weigh in the time, effort, and money to make the Bench or the Salas, and also the expertize needed not to screw the Bench... The 5-10% specific area difference is up to personal taste. In general, they are in same class for transparency, projection, and sheer musicality.
 
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Silver/Oil I use. Its a matter of a combination of things. In my assortment of parts and circuit decisions, PSU etc, it works balanced. But yes, if the circuit and parts or MC & speakers tend to be higher midrange projecting, an S/O will not help. A Jensen Copper Foil would do better in such a case.
 
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No, it was from Sound & Hi-Fi Greek magazine. About 10lt closed, Acoustic Butterworth crossover with no baffle step. Was to be combined with a B139 sub. But I made a bigger one, BR with a double coil Audax 30cm (12inch), sensitive enough unit and a central passive crossover at 170Hz.

*Nicoch46, I am tuning a special 40dB version for the DL-160. Will show soon.
 
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High MC out version

This is the version that the gain, loading and sound is the best I could find for high output MC. I used the Denon DL-160 as a standard. Sounds really neutral as a combination. In case someone needs some more gain, the Rsource 50R can go down to 33R. I was more than OK with 40dB and the Denon, that looks like producing more than its nominal 1.6mV to me, rather something like 2mV+. But I have sensitive speakers too. The 120nF coupler can be 100nF. The Cout is arbitrary value. See the Salas MC comments on the page before for that.

So we have 3 options: The MC Salas RIAA for 0.5mV, the same can be modified with a 1st stage Rsource bypassing capacitor as shown on its schematic (previous thread page) for +6dB and 0.2mV carts, and this last one with low PSU, and a couple of resistor value changes for high output MCs, 1.5mV-2mV or 1mV with 33R Rs. All 3 options are well tuned, checked, and thoroughly auditioned. Using a variable regulator for B+ someone can easily modify the MC version for high MC in 10 mins with a soldering iron.

That's about it.
 

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diyAudio Chief Moderator
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In my case it worked more open and correct @ 1k. It tends to spray HF distortion and more noise with high RL. My guess is that in non neutral systems with a bit of bass boom & beaming HF, high RL compensates and sounds ''open''. But I will listen again with 15k after more break in, maybe my impression is going to change.