Current source on 3886 mute pin

[Michael Bean]

Hi All...

I was just sittin' here idling away some time when outta nowhere this question pops into my brain; since I don't normally use the mute function on a LM3886, would there be any audible benefit to using an active current source instead of the usual resistor?

Any thoughts?

Mike

 

[diy_audio_fo]

Hi All...

I was just sittin' here idling away some time when outta nowhere this question pops into my brain; since I don't normally use the mute function on a LM3886, would there be any audible benefit to using an active current source instead of the usual resistor?

Any thoughts?

Mike

Look at

http://www.rane.com/pdf/old/ma3sch.pdf

the schematic of MA3 amplifier by Rane (Rane Corporation)

 

[Michael Bean]

Thanks, but that doesn't really answer my question whether or not there would be any audible benefit to doing it. I suppose I could get off my lazy butt and try it, but I thought I'd see if anyone here has already tried it.

Mike

 

[djoffe]

At least by straightforward simulations and thought experiments, there is no benefit to a current source on the mute pin. Having said that, I use a current source on the mute pin in my products...

for example, take a look at this assembly manual, the schematic one page from the end....Q2, D3, and R6 are a current source for the mute. But, if you look at the schematic of the LM3886 internals, it just switches an internal current source. I can't see any real difference, assuming responsible design.

http://www.updatemydynaco.com/documents/AssemblyManualRev2.08.pdf

 

[Michael Bean]

Hi djoffe,

Yeah, I took another look at the data sheet and it appears you're right, there's probably nothing to gain by going active there.

So once agian, no marching bands or awards for my great ideas! Oh well


Mike