BOSOZ volume control

[ToB]

Hi

If I have to chose only one side of volume control(input or output), where should i put it? Is there any modification on main board for elimination? I use balanced.

Thank you for input
ToB😕

 

[Peter Daniel]

If you can find small enough value (below 5K), it would be better at the output.

 

[UrSv]

I think that the manual for BoSoZ suggested that one of the best set-ups would be to put a fixed resistor attenuator at the input, as the performance was best with 1-2 V output, and then the volume control at the output. The 10 dB gain example was 0.3 V in for 1 V out.

Ref bottom right on page 7.

/urSv

 

[Peter Daniel]

If your source component has a high output this would be prefferable, but it's not always the case. Less resistors in the signal path the better sound. 😉

 

[ralf]

stepped attenuator

I build a stepped attenuator with 5K and put it on the output of BoSoz, cause there the speakers are without "sssssss"

Regards,
Ralf

 

[skaara]

I have them at output, because when you are listening to lower levels, you reduce noise too.

 

[ToB]

Thank you all🙂

For P3, P4, I'm wondering in step attenuated calculation. If P1, P2, P5 will be deleted and R15=430 ohms(10db), what configuration to calculate? I will use 12 steps-4 decks rotary switch.

Shunt or Single sieries shunt attenuator, is good for this project?
Could you recomend any web that has resistor calulator?

Thank you

ToB

 

[MarkL]

I build a BoSoZ with 3 controls, all discrete with stepped switches: 0 to -11dB ladder at the input (two, 4-deck switches), with separate left and right to enable some balance, a 5dB per step master shunt attenuator at the output (one, 4-deck switch), and a 5dB per step gain control linking the two MOSFETs (one, 2-deck switch).

If I were to do it again, I would eliminate the input ladder, expand the range of the gain control, and have fine attenuation as a shunt at the output (two, 2-deck switch).