- No ideal hfe. They will all work. Use an average from your stash. For Idss, around 7mA for the K170.
-120R has to do with the bandwidth and phase also, try 100R not 150R. If you get any problems revert to 120R even if not especially low for self induction.
-No its not. Use a generic green led.
- Use 4R7 for R1, it will run about 130mA. 30mA for each phono ch. and 100mA to run each reg warm enough. That will mean near 3.6W dissipation from each shunt element and 1.3W from each CCS element for 45VDC in & 36VDC out. I think that your copper plate will suffice.
-For C1 yes, for C3 not optimal.
-R13 nothing special. I used 1/4W metal film.
Im a looking at the wrong schematic?
C1 is 33pF, I'm using a glimmer type from reichelt for it.
Are you talking about C2, parallel to the reference resistor?
Here I have white Mundorfs, and another version with red wimas. I couldn't distinguish them sonically.
As for C3 (output cap) I have nothing special, just a Panasonic FC. I did not try fancy foil caps here, yet.
Rüdiger
C1 is 33pF, I'm using a glimmer type from reichelt for it.
Are you talking about C2, parallel to the reference resistor?
Here I have white Mundorfs, and another version with red wimas. I couldn't distinguish them sonically.
As for C3 (output cap) I have nothing special, just a Panasonic FC. I did not try fancy foil caps here, yet.
Rüdiger
You use V1.2, we talk V1.2R from post #3200. You by using an FC for V1.2 you have something between 1.2 & 1.2R. Since you find it good for your head amp with the parts you got, I don't see why tweak it further. In what way you found it better than gel batteries? I had same impression in an older test on my phono (had it on cap bypassed batteries initially before developing the regs) and some feedback in the same vein by a user who changed from batteries on his OPA627 line pre.
I had a feeling of more 'grip' and firmness. I couldn't say it had more resolution, but maybe even that. I gives full and liquid bass and free and easy trebles, like the batterie, and maybe a tad more of it all. And of course, you don't run any few minutes to check if the batterie is still sufficiently loaded...
I experienced to get a mixed bag when substituting batteries with super regs, with these shunts, i don't miss anything.
Technically i appreciate very much the thin green line the shunts show on my scope. That is cleaner than anything I ever tried except batteries!
Rüdiger
I experienced to get a mixed bag when substituting batteries with super regs, with these shunts, i don't miss anything.
Technically i appreciate very much the thin green line the shunts show on my scope. That is cleaner than anything I ever tried except batteries!
Rüdiger
All depends money you can spend, the best:
R11 Rref resistor Vishay "naked" Z foil TX2575
-TCR 0.005 ppm/°C (0°C to +60°C)
-Tolerance ±0.005%
-Current Noise: 0.010 μV/ºC Maximum; 0.05 μV/ºC Typical;
1 μV/ Watt
C1 & C3
Solen 1000VDC, 3Q Series, Metalized Teflon
The simulator shows 4-5 MOhm at 100Hz. Its CCS input, in any real situation Zi will be very high for linear PSU hum frequencies.
So I do not need to worry about that 
I am considering a TT crc filter (15000u - 6r - 15000u) f now.
My present setup is a simple rc filter (6r - 15000u) and the 6r was put there to reduce from 50v to 45v... but it works very well for filtering purposes.
Introducing the second cap before the rc can I expect a reduction on psu Vout ?
The shunts are producing 37v so 45-37=8v... I guess this is the minimum to make the shunts work ok, so I would not like to reduce the psu Vout further.
I am considering a TT crc filter (15000u - 6r - 15000u) f now.
My present setup is a simple rc filter (6r - 15000u) and the 6r was put there to reduce from 50v to 45v... but it works very well for filtering purposes.
Introducing the second cap before the rc can I expect a reduction on psu Vout ?
The shunts are producing 37v so 45-37=8v... I guess this is the minimum to make the shunts work ok, so I would not like to reduce the psu Vout further.
no.
More likely to see a small increase in average voltage from the PSU.
The PSU has pure DC available when there is no current demand.
The level of this DC is the peak voltage at the secondary less the zero current Vf of the rectifier.
Draw some current and the PSU is no longer pure DC. It is DC with a sawtooth waveform superimposed.
The ripple voltage of this sawtooth waveform is dependent on the inverse of smoothing capacitance and dependent on the output current drawn.
The maximum voltage of the rippled DC is peak secondary voltage less the Vf of the rectifier when passing current, less a tiny Vdrop in the wiring and secondary resistances.
The average of the rippled DC is ~zero load DC - minus 50% of the ripple voltage minus a tiny Vdrop.
If you increase the smoothing capacitance you reduce the ripple voltage.
The average DC voltage from the PSU increases as you increase the smoothing capacitance.
The ripple voltage falls as more RC or LC filter stages are added to the PSU output.
More likely to see a small increase in average voltage from the PSU.
The PSU has pure DC available when there is no current demand.
The level of this DC is the peak voltage at the secondary less the zero current Vf of the rectifier.
Draw some current and the PSU is no longer pure DC. It is DC with a sawtooth waveform superimposed.
The ripple voltage of this sawtooth waveform is dependent on the inverse of smoothing capacitance and dependent on the output current drawn.
The maximum voltage of the rippled DC is peak secondary voltage less the Vf of the rectifier when passing current, less a tiny Vdrop in the wiring and secondary resistances.
The average of the rippled DC is ~zero load DC - minus 50% of the ripple voltage minus a tiny Vdrop.
If you increase the smoothing capacitance you reduce the ripple voltage.
The average DC voltage from the PSU increases as you increase the smoothing capacitance.
The ripple voltage falls as more RC or LC filter stages are added to the PSU output.
This might be because we have no current on the circuit and DC is measured after the cap is full right ?
Can it be easily quantified ?
Maybe I could do a good TT filter using 1000u + 6r + 15000u without loosing too much voltage
I have 40.4 raw DC before the rectifier and 44.5v after the rectifier and smoother.
I am using full wave + 6r + 15000u actually and would not like to reduce the 44.5 further.
Last edited:
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.