Place of the mute relays on Aleph P 1.7

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It's a simple question but with my inexperience in the audio matter, it's critical.
The mute + & mute - in the power board of the Aleph p 1.7 were used for a pair of relays in order to shut the signal source line. Bute Where ? In the entry? in the exit ?
Give me more informations on the classic schems.
Normally it shorts the output line to ground so there are no turn on transients (ka-thumps) from power up-power down, or from AC power line surges. These could easily damage your speakers if they are large enough. I believe that the relays are designed to prevent this from happenning at the output. I just got my Aleph "L" working and it doesn't seem to have any subsonics at turn on or turn off, but I can't say what a dynamic main AC spike or large transient would do either. It seems to be pretty well safeguarded from that without the relays. I didn't incorporate any into mine, at least for now. They can always be added later on.
Mark Gulbrandsen
Salt Lake City, UT
No I don't use a micro controler (see the thread of Aleph P 1.7 more simple in progress).
In theory I can do this but I haven't the equipement for exploit this. Before in school we have the µP and there programmer, but now the school is over and µC and programmer are very expensive. So it's not a good choice.

In remplacement I have two choice:
- Two simple push button coupled with a counter thaht give a binary god for driving transistor who drives the relays.
- A potentiometer with a analog/digital converter that give the sema binary code as below. But the problem with this solution is when the potentiometer wasn't enough stable, we have the risk that the one or more relays click continuly (because the converter can be disapointed with some intermediate voltage from the pot)

We have also the Alps grey coder solution but I prefer some digital schem.
digitally controlled....

You could do something simple. create a mecchanical contraption that gives a sequences of pulses (complexities can range from the 1 mocroswitch up and other one for down, or a wheeel whith holes and a photodetector). Use a simple n bit counter, and drive the relays with the output. You can find counters in every logic family, even in a simple ones like the ancient 7400 series.

I dont think the AD0804 is stable in the LSB anyhow but if you are to disconect the to LSB:s then i dont think it will be a to big a problem. (i will test it this weekend if i got the time....damn this weekend is already over =///)

hmm maybe one could "mutulate" some old mouse to take the optics from...that might work....

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