Aleph 4 LED

So I've been staring at the Aleph 4 schematic for awhile trying to work out what the LED tied into the output does....

I'm assuming that this is some kindof indicator, possibly indicating clipping?

If this is an indicator though, wouldn't there be some set parameters for the diode? It just indicates some random LED there so that's what's confusing me....
Hello Jduncan,
I think that this is only due to a layout convenience, in fact the blue led is positioned on one of the 4 of the output Hexfet PCBs.
Of course the LED's light is modulated by the output signal, but the audio frequencies are too fast for our retinas, we only see his mean value, that is constant, from 0 to the maximum output power.

[Edited by tortello on 11-15-2001 at 09:39 AM]
the reason I asked is that ALL the aleph schematics have it connected into the output (or close enough) and when they corrected the other mistakes on those schematics (the aleph 4 in particular had things like x3 instead of x6 for the number of output mosfets etc) they didn't change this.

It's also a pretty monumental "mistake" to draw that into the output rather than straight to ground.....

So I'm thinking that it was there for a reason, but that volksamp decided not to keep it when they moved to the aleph 30/60.

I'm just interested in the reason ;)

Joe Berry

2001-03-15 6:15 pm

There's no harm I can see in connecting the LED as shown in the earlier schematics. In fact, it could be useful as a DC fault indicator, if you knew how to read it. I'm only supposing it to be an error in light of the later schematics which show the more conventional connection.