Simplistic NJFET RIAA

Hi Salas, some pictures of my build. What would be a good value for the R in the RC filter?. Thanks.
 

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Hi Salas, the blue cap is philip 4700uF/63V. There is no hum what so over. I find two immediate features of the stage is imaging -definitely a strong point and silky smooth highs. Currently i used 2+100pF caps extra on the riaas . I did have obligatos 47nF but the leads were too big to fit on the board plus the space is a premium, not sure if it is worth while replace those mkp 1837 for now. Would the long leads from the obligato cause oscillations or degrade the performance.
Quan
 
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Hi Salas, the blue cap is philip 4700uF/63V. There is no hum what so over. I find two immediate features of the stage is imaging -definitely a strong point and silky smooth highs. Currently i used 2+100pF caps extra on the riaas . I did have obligatos 47nF but the leads were too big to fit on the board plus the space is a premium, not sure if it is worth while replace those mkp 1837 for now. Would the long leads from the obligato cause oscillations or degrade the performance.
Quan

Don't exchange C1 from 1837 to something else, small size is priority there. Long leads would add inductance. Oscillation is not easy to get there because open loop but 1% precision and mini size are better for transparency due to small area layout.

You did not advise me you raw DC measurement while power is on yet.

P.S. If that cart is 103 standard not R type do try 470R load or about if you haven't done it.
 
Don't exchange C1 from 1837 to something else, small size is priority there. Long leads would add inductance. Oscillation is not easy to get there because open loop but 1% precision and mini size are better for transparency due to small area layout.

You did not advise me you raw DC measurement while power is on yet.

P.S. If that cart is 103 standard not R type do try 470R load or about if you haven't done it.
Hi Salas, the raw DC voltage is 49V whilst power on. The denon 103(plain vanila type) had ESC stylus mod on it. I will try 470R for loading later.
Quan
 
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Hi Salas, the raw DC voltage is 49V whilst power on. The denon 103(plain vanila type) had ESC stylus mod on it. I will try 470R for loading later.
Quan

OK. Use 47R-68R 3W or 5W and another same Philips Blue for local RC cell evaluation per feed.
What is that other TT and what cart does it carry? Did you connect it to that TT too by now? How many Watt per channel you use for the Avalon Eidolon Diamond?
 
OK. Use 47R-68R 3W or 5W and another same Philips Blue for local RC cell evaluation per feed.
What is that other TT and what cart does it carry? Did you connect it to that TT too by now? How many Watt per channel you use for the Avalon Eidolon Diamond?
Thanks Salas for the suggestions, will gather parts and try later. The other turntable is Once analogue ( Australian made) / Basis vector 3 tonearm/ Dynavector XV-1S. I have yet to try it with it but will do in due course to allow the run in of the lytics. The YBA do about 250W each channel , doubling as impedance halve.
Quan
 
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That's about the power an FM Acoustics at a friend's need dump on those to properly grip them on peaks. Hungry beasts.

Yep, that other TT will reveal more traits of the phono. And its wise to run it in for the lytics to wake up before going there. But at what loading you have the 103 playing as by now?
 
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I will try progressively up the loading and see what happen. Few things need to be sort out- appro fuse- my currently 800mA T , previous one was 250mA but did not last long, had a bit of a zap on touching the case- not sure if it is static or leakage . I will measure the AC leakage and see what happen.
Quan

OK we cross posted. Up the ladder or down the ladder you will home in. No problem.

About fuse, whatever the VA dictate. Most Tx have an indication of what to use on their labels.

I haven't had a zap on the chassis till now. Do check. You got the IEC earth bolted to psu chassis yes?
 
OK we cross posted. Up the ladder or down the ladder you will home in. No problem.

About fuse, whatever the VA dictate. Most Tx have an indication of what to use on their labels.

I haven't had a zap on the chassis till now. Do check. You got the IEC earth bolted to psu chassis yes?

My transformers are 30Va and 80VA ( 18+18V). Yes i do earth the IEC .I measured the AC voltage btw earth prong and chassis whilst power on recorded zero voltage. Must be static then?. It was a cool evening and was walking on carpet.
Quan