SSLV1.1 builds & fairy tales

[merlin el mago]

What can do to suite for pcm1704?

 

[samoloko]

I have used D1 I/V with IRF610 and pcm63 and were not pleased
then modified with 2sk170
some diyers even recommend swapping D1 I/V with quality OPA

 

[merlin el mago]

If the regulator outputs are located exactly on the amplifier power inputs then the local MF & LF decoupling can be dispensed with.
You can design the two PCBs, PSU & Amplifier, to stack bottom face to bottom face to get as little as 2mm of lead length (a solid copper link) to make best use of very short lead lengths and very low added inductance.

I am not so sure the HF decoupling can be dispensed with, I suspect this is still required across the main output device, i.e. right across the output device, T2a Drain PIN to R4a GND PIN.
C7a is shown in the wrong position on the schematic. C7b may be near useless in it's present location.

Your proposition is like the attached schematic?

 

[merlin el mago]

I have used D1 I/V with IRF610 and pcm63 and were not pleased then modified with 2sk170

Same voltage +-30V, wich Idss & grade BL?

 

[Salas]

Your proposition is like the attached schematic?

If you do that you will probably have oscillation problems with the reg. You should keep the buffer in-line resistors if you will do that.

 

[merlin el mago]

OK thanks Salas your input is always really appreciated.

 

[AndrewT]

what value of resistors? 0r1, 1r0? Not 10r.
How do we find 0r1, that are 2mm long, to place between the two back to back PCBs?

 

[Salas]

1R suffices to buffer the 0.1uF from strongly affecting the reg's zobel, saving from shorting phase margin drastically.

 

[samoloko]

Same voltage +-30V, wich Idss & grade BL?

yes voltage Is same
search for a thread - fine tuned D1 convertor from a member Klaus around 2004
but I guess that Patrick Sen would be even better

BTW Is your pcm1704 a stock dac and not diy - have you compared stock output with D1 I/V

 

[merlin el mago]

The other I/V is tubes so I can't compare, the pcm1704 is the Elektor DAC2000

 

[samoloko]

there Is HB pcm1704 dac which was a test for Erno Borbely I/V convertor

search thread that I posted about jfet I/V - think that deserves attention

 

[merlin el mago]

I own Erno Borbely All Fet I/V Converter and Filter for DACs EB-201/214/DAC13, the new I/V is for a friend.

 

[samoloko]

It will be Interesting to tell us your Impressions when you compare both output modules

now to the topic

what type for 1R resistor Is recommended for regulator output and for bases of BPO transistors

 

[merlin el mago]

Is better EB

 

[AndrewT]

Is better EB

Is this a question, or a statement?

 

[merlin el mago]

It's simply my subjective opinion.

 

[AndrewT]

Which is better than what?

 

[merlin el mago]

For BB PCM1704 is better Erno Borbely All Fet I/V Converter and Filter for DACs EB-201/214/DAC13 than Nelson Pass D1 I/V.

 

[merlin el mago]

Salas with the BiB (without taking of C1, C4, C7, R1 & R10 of the NP D1 I/V) the sound crackles like on the discs of vinyl😡

 

[Salas]

Take them out or drive wires directly to a point after them. To see if its periodic oscillation problem between the two circuits. Without scope analysis and measurements we stab in the dark, but give it a try.