Simplistic NJFET RIAA

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Of course, I experimented with 100n, 47n, 33n, 10n, 1n, 470p, 120p, 40p, 25p, 10p.

I found that the bigger the cap, the more influence it makes in the mids.

In one build I have 10n because It lacked mids.

In the other build I have 10p because I only needed more highs.

The effect also depends on the type of cap. For more presence in the mids I found a good MKP is best. For highs a SM or Teflon is the best.

Fortunately I found these 10nF 2000V:)

I want to do something like the schematic but I am not sure where to connect the TT earth wire.

1) to the chassis ?

2) to the circuit zero volt line ?

I'm also interested about the virtual GND connexion.
 
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Caps pic
 

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Those might be good to bypass the shunt´s output zobel cap (only bypass the cap ... not the zobel)

Of course you use much better film caps there than myself so it might not sound the same... In my case a 10nF // 4u7 on the output zobel enhances mids and highs.

10pF // 4u7 only affects the extreme high freq.
 
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Those might be good to bypass the shunt´s output zobel cap (only bypass the cap ... not the zobel)

Of course you use much better film caps there than myself so it might not sound the same... In my case a 10nF // 4u7 on the output zobel enhances mids and highs.

10pF // 4u7 only affects the extreme high freq.

I'm using V1.2R regs & I have installed time ago 0.1uF teflon FT-3 in parallel with C1 & I like it so don't change, finally I decided to lower the VTF to 2.3 or 2.4gr depending recording. As I understood C3 can't be bypassed or yes with 10nF?

195554d1289162001-simplistic-salas-low-voltage-shunt-regulator-v1.2r-beta.gif
 
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Is it dangerous to lift the preamp -V from chassis/Earth ?

I experimented with a 10r and 100r.... 100r is better, lowering 50hz hum. I was wondering about too paralelled (oposing ends) rectifier diodes... Can this damage anything ?

Yin Yang they call them some times. No, you can't damage. If you got some equipment that hum when hooked up in a system and some that don't, its a complex issue, there are many threads on system grounding if you search the forum, and articles on the web. Usually its a loop through interconnect shields and mains ground returns, some times solved in the power amp with that diode bridge fail safe lift. It transcends the phono, its a general issue. My builds are fully grounded to chassis with mains earth attached too for instance. They never hummed in the few different systems I hooked them up by now.
 
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Thank you Salas

I know the issue transcends the phono. My preamp has different inputs and depending on the input used, I sometimes get hum.

Using a "cheater" plug I completely eliminated hum because the loop closes in the mains earth wiring.

I will experiment lifting the phono -V with the Yin Yang diodes and report.
 
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I solved the slight hum by rerouting the TX cables inside the case.

Lifting -V is detrimental... I can distinctly hear better bass with -V connected to mains Earth and it does not improve hum at all.

Also experimented with a filtered mains inlet and it provides a lower noise floor but somehow mutes the highs. If I needed to use the filter, I probably would need to retune the shunts.

I would like to try this balanced mains filter from Ray´s site: http://www.raylectronics.nl/index_en.html

Another day, another lesson :)
 
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