B1 Buffer Preamp

[labjr]

15,000 seems a little overkill. Maybe inrush current is a little high. But don't those three pin regulators have overcurrent protection? I'd think a discrete shunt regulator circuit would work better.

[tinitus]

isn't the B1 supposed to be used with a 'standard' external regulated supply
I even think a particular one is suggested in manual

with this low 'power' draw, I guess its basicly like running on batteries

unless...maybe shut down bleeders may be working against this


funny....but I think I have read that high capacity caps will be replacing much more battery functions in the future

[tinitus]

actually, with a 100.000uf cap I reckon a B1 would work all day, dissconnected from power source

mind you, I'm not suggesting to do that
only saying it might be possible

[6L6]

The stock value of 15,000uf is there so the original PCB can be used with an unregulated supply, such as a wall-wart.

If you have a regulator, a smaller value cap could be appropriate.

[Bengali]

Killing it in what sense, making it useless?

not useless but not as effective(?) I read somewhere the output of the regulator does not want to see a large capacitance. The large capacitance should be on the input side of the regulator. that's why I'm asking.

Mr. Pass says anywhere between 1000uF to 15,000uF so there is a good reason for the wide range. justed want to know why.

[regiregi22]

I once tried one LM3886 with a total of 200.000uF at +-35v. It stayed playing for half a minute at moderate volume with the power cord disconnected.

[tinitus]

I thought that it was large inrush current on power-up that could kill the regs ?

If you deal with that, and stays well inside the current draw limit, what else problems could there be

[clm811]

If you have a regulator, a smaller value cap could be appropriate.

Care to be more specific(Please)?

(If it helps for me to be more specific, I have a choice of the following caps: 4,700uf, 1,000uf, 330uf, 100uf, 10uf, or 1uf.) Which one?

Maybe inrush current is a little high. But don't those three pin regulators have overcurrent protection? I'd think a discrete shunt regulator circuit would work better.

I'm planning on using what I have on-hand (a finished LM1084 adjustable series regulator, built according to the manufacturer's applications sheet).

I have little interest in undertaking construction of another regulator circuit, (especially one that approaches the B1 in complexity).

I want to be done with it so I can listen to music soon!

Thanks all!

-Chas

[AndrewT]

Clm,
the B1 has only 2 active devices in each channel.
It does not need a regulated supply.
Just follow Pass build instructions.

[regiregi22]

100/200uF plus 0.1uF film should be OK.