MUSES 72320 electronic volume

[ClaudeG]

Either way, reading all the posts, it doesn't sadly seem simple (= no display, no polluting electronic) and is likely to be expensive at the end... not due to the chip, but the extras needed.

It would be nice to have a complete fail safe proposal for less than 50E... perhaps I got it all wrong with the knob feeling and "children safe position reading"... perhaps no knob at all, ie remore control only is the (childen) safest while also the cost effective solution after all...

Claude

[tombo56]

Originally Posted by jean-paul

A stepped "make-before-break" attenuator would be a better choice I guess. You don't want any noise/crackling to have influence on the output level.

That would defy one of Muses advantage points: fine volume control. I suppose one capacitor at potentiometer viper would solve any noise and crackling issues. Even some delay in volume change due big capacitor, after potentiometer position change, wouldn’t be a problem.

[airglass]

tombo56 -
What size are the smd resistors and transistors on your EM14 to Muses adapter board,
if I may ask?. SOT-23 or other? Nice little board, by the way.

[tombo56]

Resistors are 0805, same as on the Muses board. Transistors are SOT-23. Any NPN transistor would do. It doesn’t have to be BC817.

[jean-paul]

Originally Posted by tombo56

That would defy one of Muses advantage points: fine volume control. I suppose one capacitor at potentiometer viper would solve any noise and crackling issues. Even some delay in volume change due big capacitor, after potentiometer position change, wouldn’t be a problem.

A capacitor is not enough I think but you are right that "fine" would don't be the best description A course and an added stepped attenuator for fine adjustment would solve it but at the expense of complexity.

[APK]

Hi Meldano
Any further news on

BTW: Actually I build a new controller board with a STM32 and many features like conventional pot, programmable steps, optional input channel switching, Muses 72320 or 72323 option...

Very interested in the new 72323

[meldano]

Hi,
the 72323 did a good job in my main system.
I'm currently waiting for the new controller boards to be delivered.
I think the software will be ready in 1-2 months.

[Bensen]

Can't wait till you have it ready!
Is there an input selector incorporated? If not I'm proceeding with the one I'm working on right now.

Regards

[McQuaide]

Originally Posted by meldano

The PSU in the manual was only for testing (LM317/337).
Pass Labs use the NJR 78/78

I tested the NJR, LM317/337, LT3045/3094, TPS7A49/TPS7A30

In my main system (Pass clone) I prefer the TPS types.
My college prefer in the same Preamp the NJR.

Meldano do you have a link to a NJR regulator?

[meldano]

Mouser:
513-NJM7815FA

The NJM7915FA is obsolete