MUSES 72320 electronic volume

Thanks Jean-Paul!

An encoder with stops would indeed do the trick for me and still save us from a display while mechanicaly spotting the volume position at a glance. I guess one just needs an encoder with enough steps to allow a reasonable volume adjustments - I don't need quarter dB steps :). And of course I don't mind if there is still a push button with it for some functions, but important is indeed we get that mechanical and visual feel for volume.

Project anyone?
 
What about a simple volume control based around that new promising chip, but for a change one that could replace an existing volume knob in an existing amp?

Would it be that difficult to have just that chip and a very cheap conventonal pot (motorised or not) just acting as command / order, piloting the attenuation of the chip?

It could replace existing volume pots behind knobs and the volume knob position could tell where we are in terms of volume, rather than needing a display or hope for the best if you youngest has turned the endless wheel... it would also be much cheaper that way for those not needing a remote, 50$ being competitive for example.

Just thinking out loud

MFG

Claude

Your idea is interesting for a replacement and should be quite easy to do.
The muse together with a cheap MCU with an embedded ADC and a potentiometer might do the job actually. This is a quick overview but may work and will be cheap. Software easy to do too.
 
Hopefully... but all this computing and soft is not my software, hence happy to follow... I still believe t would hit a market for those looking for an affordable alternative to a pot.

Stepped attenuator is expensive and can't be motorised unless spending a fortune, all IMHO

Claude
 
Single deck switches are not that expensive. Remote control will be an issue :)

The hope is that an encoder with end stop exists.

To control the muse and all the steps needed especially the new one with 0.25dB, on less that 360 degree rotation for the encoder means that it will be an encoder with high resolution like 512steps.
In theory it could be possible putting two mechanical limit on a normal encoder or the knob and calibrating both ends with the adjustment range of the muse.
 
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Bourns EM14 to Muses adapter

I understand that I may be the only one in the world annoyed enough with the original PEC-11L encoder to go this route, but here are details and gerbers anyway. With this adapter, Bourns EM14 encoder can replace standard encoder in any device.
Adapter PCB can be connected to the Muses volume control using connector at position for additional display (if you don’t use one, and by cutting some traces) or by soldering wires to the corresponding points. If we consider flat cable red marked wire as 1. then corresponding connection points are marked at controller PCB picture. This encoder seems perfect.
 

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I do not understand the whole discussion. You want the high quality of the Muses chip and then you make sure that you can't use it?
Who uses the whole rotation range of a potentiometer? With me, maybe 25 to 40% are used. I have some customers who have bought exactly this potentiometer so that you can fine-tune a small part of the rotation range.
A volume change from 0 to 100 in a 270 degree rotation can be easily programmed with the appropriate software. So I have implemented this solution in my software.
 
A standard pot is not really a good solution.
Noise at ADC In can toggle the output volume.
Aging, disturbances from installation etc. can increase this behavior.

Direct mapping from ADC should be avoided.
Frank, you wrote that Muses increase the resolution. Nobody forces you to implement the higher resolution. Cut off the LSB and you will have the 0,5dB steps you know from the 72320 ;)

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...