Building a symmetrical psu B1 buffer

[Salas]

To clarify the graph: The 100k was to simulate F5's published 100K Zin. Practically it would be DCB1, 1uF cap, 1Meg or more to ground, RCA, F5. 91K total if with 1Meg after cap to ground.

[Tripmaster]

Hi

I have 3.3 or 4.7uf caps to hand if you feel either of these will measure better. I'm happy to purchase a different value if required.

[AndrewT]

perfect!
Build up the source with the 1uF temporary tacked on.
Listen and evaluate.
ADD the 3u3F, also tacked on.
Listen and evaluate.

Was there any difference in the sound before and after?

Choose which you prefer and solder in permanently.

[Tripmaster]

Originally Posted by AndrewT

perfect!
Build up the source with the 1uF temporary tacked on.
Listen and evaluate.
ADD the 3u3F, also tacked on.
Listen and evaluate.

Was there any difference in the sound before and after?

Choose which you prefer and solder in permanently.

Will do. Good idea

[nightanole]

Not to get off topic, but doesnt too big of a input cap start affecting the highs?

[AndrewT]

then try mix and match if you believe this is an issue.

I believe it is far more important that the input filtering is of narrower bandwidth than the amplifier/pre-amplifier can reproduce well.
eg. setting the amplifier input filtering to F-3dB @ 3Hz and 200kHz, requires the amplifier to work well over the bandwidth of 1.5Hz to 400kHz.

[nightanole]

Guitar Pedals: R-C Filter Calculator

You figure you want your -3db to be 2 octaves out from what your system can reproduce to get rid of phase problems.

Hes got 100k in:

for full range (odds are highly unlikey either his music or his speakers can produce)20-20k
input cap would be 0.318uf for 5 hz
my simple calc wont do ultra sonic calcs.

[Tripmaster]

Hi

I have just finished wiring my L/S attenuator into the DCB1 and I appear to have some DC on right output channel, left appears fine.

When I turn on the attenuator and DCB1 at the same time the right channel peaks at ~1.4v before the relay clicks in, and then drops to 0v after the 5 second click. When I turn it off the right output peaks at ~800mV and very slowly decreases. As I am only in the checking phase I haven't connected it to my amp...thankfully

Any ideas?

Thanks

[Salas]

What happens if you are turning them on in separate times?

[Tripmaster]

Originally Posted by Salas

What happens if you are turning them on in separate times?

Hi Salas

It happens if I turn on the DBC1 first, the L/S doesn't make any difference.