That phono schematic adequately drops rail voltage by each RC while also local filtering/decoupling sections along its power rail. A very common practice in classic tube circuits.
Because its a high gain sensitive circuit don't compromise the RC uF values so it can filter as strongly as designed. There are 2.2uF film bypass capacitors parallel to the 100uF electrolytics already I see. Serving subjective quality enhancement considerations.
Because its a high gain sensitive circuit don't compromise the RC uF values so it can filter as strongly as designed. There are 2.2uF film bypass capacitors parallel to the 100uF electrolytics already I see. Serving subjective quality enhancement considerations.
Thank you, got it. As I removed MC part from original schematic, these capacitors were added by me and probably they are too big. Smaller capacitors were only on MC part. So, there is some place for experiments. On Monday I will be able to do more tests with preamp and not only with dummy load.
The tube preamp cookbook is still available from vacuum state http://www.vacuumstate.com/index.dna?lang=2&rubrik=1&kat=1&lay=art2&a=&b=734482.1568822398&sku=6 For 50 euro in Europe and 65 world wide volume 2 .
Made some more tests. Everything is working but I have some minor issues and probably unrelated to shunt. Want to measure noise and ripple if there exist any. But my equipment is probably too ancient 
Power supply is simple CRCLC filter -> Salas shunt -> phonopreamp. I can measure ripple before 20H choke:
but I can not get clean line on oscilloscope in mV range. When probe is shorted to ground star point there is quite big noise level:
Probably very noisy environment. And I think this noise somehow gets into power line. On normal listening level and position everything is ok but when music is not playing and volume set to max level there is noise. And difficult to say 50 or 100 Hz is dominant. Probably my grounding scheme is incorrect and I have some ground loops.
Power supply is simple CRCLC filter -> Salas shunt -> phonopreamp. I can measure ripple before 20H choke:but I can not get clean line on oscilloscope in mV range. When probe is shorted to ground star point there is quite big noise level:
Probably very noisy environment. And I think this noise somehow gets into power line. On normal listening level and position everything is ok but when music is not playing and volume set to max level there is noise. And difficult to say 50 or 100 Hz is dominant. Probably my grounding scheme is incorrect and I have some ground loops.
Raw DC ripple measurement is picked up correctly i.e. 100Hz saw-tooth shape.
The other noise has shape and frequency which are weird indeed. Could also be common mode noise interference.
Proximity to power transformer field or to choke field can also do harm. The ripple peaks are sharp and the choke is a coil. Can emit.
Try something simple to see if its interference or how much of it:
Keep the probe attached to where you see the weird noise. Then power down the device under test. Does the noise change or disappear?
If all or some of it remains its a kind of interference in the test loop. If it disappears its a produced noise in the PSU & phono system.
Some noise in high gain and tiny input signal systems like phono is expected especially in max volume. But we always try to make it smallest possible.
The other noise has shape and frequency which are weird indeed. Could also be common mode noise interference.
Proximity to power transformer field or to choke field can also do harm. The ripple peaks are sharp and the choke is a coil. Can emit.
Try something simple to see if its interference or how much of it:
Keep the probe attached to where you see the weird noise. Then power down the device under test. Does the noise change or disappear?
If all or some of it remains its a kind of interference in the test loop. If it disappears its a produced noise in the PSU & phono system.
Some noise in high gain and tiny input signal systems like phono is expected especially in max volume. But we always try to make it smallest possible.
Changes solid-state rectification to EZ80 tube and now looks like with ground line on an oscilloscope everything more or less is ok:
still some noise but definitely less. With better cabling and closed case probably will be even better. Well you never listen music with max volume level even not close to it so it is just question of perfection. Noise on power line:
But I still do not trust what I see. My probe probably is not the best one. I can not measure a ripple at the input of shunt regulator. Probably it is so small that I see just a noise. But I am happy with sound
still some noise but definitely less. With better cabling and closed case probably will be even better. Well you never listen music with max volume level even not close to it so it is just question of perfection. Noise on power line:
But I still do not trust what I see. My probe probably is not the best one. I can not measure a ripple at the input of shunt regulator. Probably it is so small that I see just a noise. But I am happy with sound
Star is not best for this I think. Try something different and compare result:
1. Connect 0 Force and 0 Sense lines directly to the phono's 0 power input.
2. Keep protective earth and transformer static shield to chassis point as is.
3. Connect output RCA gnd locally to the phono board's signal ground line.
5. Make two diodes lift bypassed with 10-100nF capacitor and 10Ω resistor.*
6. Connect the signal gnd to chassis earth through the safety gnd lift device.
*Like in this example: https://sound-au.com/project04.htm
1. Connect 0 Force and 0 Sense lines directly to the phono's 0 power input.
2. Keep protective earth and transformer static shield to chassis point as is.
3. Connect output RCA gnd locally to the phono board's signal ground line.
5. Make two diodes lift bypassed with 10-100nF capacitor and 10Ω resistor.*
6. Connect the signal gnd to chassis earth through the safety gnd lift device.
*Like in this example: https://sound-au.com/project04.htm
R3 C5 not needed, delete and replace with just green line wire. Move GND symbol to X3-1,7 node. Its chassis earth. Safety ground lift device is the D1 D2 R2 C4 circuit. Keeps mains earth/chassis separate to signal ground. By 0.7V diodes lift. So no ground loops with other gear are possible through mains earth. But if bad damage happens in the phono the 0.7V is exceeded, diodes open and all grounds get directly connected. That is why safe ground lift. Use D1 D2 diodes with current capability as much as your transformer's primary fuse or more. For R2 use 2W power spec or more.
Made some more tests. Changed a little bit power supply. Removed C1 capacitor, R1 is 4R7, C2 and C3 changed from 330uF electrolytics to 30uF MKP. Some mess on the table but sometime is good to see a picture On the Shunt input I have 306V and on the output 286V. I need only 6-7mA for phonostage, so totally 26-27mA but minimum what can I set is about 30mA (304mV on test points). Probably this is not bad.
I have a box of MKP capacitors hope they are better then electrolytics.
Grounding scheme works but can not say that there is a dramatic change. There is a change when I put phono board into metal case.
I tried to short an inputs and of course noise reduced but still on max volume I can hear some strange sounds like Morse code. Well with very high volume settings (normally you do not use such) when music is on pause there are no hum or any unwanted sounds. At least I can not hear it. Probably I am digging to deep. And I understand that problem not with the shunt, it works just great. Now I am experimenting with EAR834P clone and it has very high amplification and probably not the best layout. But probably the worst thing is that I want to put everything in one wooden box with open top. Bottom is perforated metal plate and power supply is separated also with metal plate:
On the Shunt input I have 306V and on the output 286V. I need only 6-7mA for phonostage, so totally 26-27mA but minimum what can I set is about 30mA (304mV on test points). Probably this is not bad.I have a box of MKP capacitors hope they are better then electrolytics.
Grounding scheme works but can not say that there is a dramatic change. There is a change when I put phono board into metal case.
I tried to short an inputs and of course noise reduced but still on max volume I can hear some strange sounds like Morse code. Well with very high volume settings (normally you do not use such) when music is on pause there are no hum or any unwanted sounds. At least I can not hear it. Probably I am digging to deep. And I understand that problem not with the shunt, it works just great. Now I am experimenting with EAR834P clone and it has very high amplification and probably not the best layout. But probably the worst thing is that I want to put everything in one wooden box with open top. Bottom is perforated metal plate and power supply is separated also with metal plate:
Nice progress. Congratulations. See if the heaters supply plays a role in the noises. Are the heaters referenced to ground? In most cases that helps. The MC/MM select relay supply must have no ripple too. Because the relay's coil is nearby to very sensitive signal contacts. In DIY if with given type of cartridge in use better bypassed. The input signal path in a phono must be simplest possible and well shielded in general.
When mains wiring and power transformer are in the same box takes extreme care so to achieve negligible harmonic noise. Magnetic shielding of the transformer must be top notch and still placed farthest possible from the phono input RCAs and associated first stage tubes. Metal plate box sectioning can not stop low frequencies magnetic fields like 50Hz.
Sectioning helps against RFI if the box is all around metal too. Also helps if there's a high frequency noise source in the box like stray field from an installed SMPS.
Your transformer is in that nickel plated pod? Do you also hear some hum and buzz at max or only hiss and weird radio code like noises? Metal wrap box played a role you said. But your tube shields I saw in a picture in post #6,786 don't make a difference?
When mains wiring and power transformer are in the same box takes extreme care so to achieve negligible harmonic noise. Magnetic shielding of the transformer must be top notch and still placed farthest possible from the phono input RCAs and associated first stage tubes. Metal plate box sectioning can not stop low frequencies magnetic fields like 50Hz.
Sectioning helps against RFI if the box is all around metal too. Also helps if there's a high frequency noise source in the box like stray field from an installed SMPS.
Your transformer is in that nickel plated pod? Do you also hear some hum and buzz at max or only hiss and weird radio code like noises? Metal wrap box played a role you said. But your tube shields I saw in a picture in post #6,786 don't make a difference?
Thank you. I think with heaters everything is ok. Heaters are elevated about 36V from ground and no MC/MM relays because I have only high output MC and MM. Also tried to power heaters from battery, so no ripple at all and situation was the same. And yes, transformer is in that metal pod. At max volume light hum also exists. But I think it is related to EAR834 and most likely due to my PCB design mistakes. With D.Klimo LAR there no weird Morses code only very light hum.
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