the PSU should be designed to be stable when the current demand changes.
That's as far as the PSU can go. After that, improving, or changing, the PSU has no effect on how the LOAD changes it's DEMAND.
The load determines what local decoupling is needed to minimise distortions of the current consumer to it's own demands on the supply rails. If the DAC is well designed it will already have the necessary decoupling fixed in the correct locations to minimise distortion due to it's own operations.
If it's well designed but built down to a pricew there may be places where improvements to the DAC's decoupling can be made. These DAC changes/improvements have absolutely nothing to do with how the PSU remains stable into changing load currents. That is a completely separate (PSU) design issue
That's as far as the PSU can go. After that, improving, or changing, the PSU has no effect on how the LOAD changes it's DEMAND.
The load determines what local decoupling is needed to minimise distortions of the current consumer to it's own demands on the supply rails. If the DAC is well designed it will already have the necessary decoupling fixed in the correct locations to minimise distortion due to it's own operations.
If it's well designed but built down to a pricew there may be places where improvements to the DAC's decoupling can be made. These DAC changes/improvements have absolutely nothing to do with how the PSU remains stable into changing load currents. That is a completely separate (PSU) design issue
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If you will ever get interference between your gear and the PSU's calculated termination because of near feeding point decoupling and this PSU's large bandwidth, you may try 0.1R in series at the feeding point and/or 100uF across sense wires at the PSU's output connector IF you will see anything weird when scoping the rail. Solid tantalum decouplers are nice.
for an example let take Pass D1 - SM available
It uses electrolytic 220 uF local decaupling caps at psu dac pins
It also uses serial 3 pin regulators at psu
If I want to replace serial 3 pin regulators with BIB with 10 - 100 uF out cap what value Is recommended to use at dac psu pins - original electrolytic 220 uF or something else
It uses electrolytic 220 uF local decaupling caps at psu dac pins
It also uses serial 3 pin regulators at psu
If I want to replace serial 3 pin regulators with BIB with 10 - 100 uF out cap what value Is recommended to use at dac psu pins - original electrolytic 220 uF or something else
BiB Manual
"JFETS/IDSS
Toshiba 2SK117GR is used, has shown better stability as a CCS than 2SK170 in this reg
and more bandwidth. The noise is on par with 2SK170 but the capacitance is half. Its -Vp is
also suitable for the small voltage margins in some crucial positions in this design.
By testing a few, 3-5mA IDSS range in the GREEN(GR) group were plenty.
You should select yours for falling in that range also, by following this tutorial:
Transistor matching
There is no need for strict matching, use your lower ones from the 3-5mA subgroup for
Q102,202,302, your medium ones for Q103,203,303, and your stronger ones for
Q105,205,305. Last but not least, 2SK117GR is currently cheaper and more available."
I doubt you get 3mA with BL grade
"JFETS/IDSS
Toshiba 2SK117GR is used, has shown better stability as a CCS than 2SK170 in this reg
and more bandwidth. The noise is on par with 2SK170 but the capacitance is half. Its -Vp is
also suitable for the small voltage margins in some crucial positions in this design.
By testing a few, 3-5mA IDSS range in the GREEN(GR) group were plenty.
You should select yours for falling in that range also, by following this tutorial:
Transistor matching
There is no need for strict matching, use your lower ones from the 3-5mA subgroup for
Q102,202,302, your medium ones for Q103,203,303, and your stronger ones for
Q105,205,305. Last but not least, 2SK117GR is currently cheaper and more available."
I doubt you get 3mA with BL grade
Thanks, but I have all the stuff in my drawer. In the evening I did find 3 pieces of 2SK117GR too 
. I built a BIB with IRF9610 and IRF9530, DC=17 V, R101= 9 ohm/5W, 4 blue LEDs. D 101= 1 red LED, R105 trimmer=5Kohm. Output is 12,6 V, and the dummy load= 94 ohm. Unfortunately I can't adjust the output, red led is off :-(. I measured 2,6 V at R101, 4blue=7,9V. Any thoughts? Thanks.
. I built a BIB with IRF9610 and IRF9530, DC=17 V, R101= 9 ohm/5W, 4 blue LEDs. D 101= 1 red LED, R105 trimmer=5Kohm. Output is 12,6 V, and the dummy load= 94 ohm. Unfortunately I can't adjust the output, red led is off :-(. I measured 2,6 V at R101, 4blue=7,9V. Any thoughts? Thanks.
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