Re: Here we go again

[kflint@annihilist.com (Kim Flint)]

>I've got another Echoplex wierdness alert:
>
>Just now, after leaving the Echoplex on unused for about twenty minutes,
>I tried recording a loop.  Without entering any sound in, and without
>having the threshold engaged, the thing automatically started recording
>once the engage button was pressed.
>
>But now here's the wierd thing.  When I hit record again, I got a very
>nasty blst of digital white noise.  This happened several times in a
>row.
>
>I switched the thing off, and upon re-powering all was well (at least it
>seems that way).  Now, is this something anybody's ever heard of?  I've
>never run into this anomaly before.  Will this be solved by clipping the
>internal thermal thing?

This is a weird one. It doesn't sound like a bug. It seems like a one-off
event where something screwed up the processor's memory. (cosmic rays, sun
spots, poltergeists, static discharches, secret military tests, etc.) Could
have been a thermal thing, but I sort of doubt it. If it keeps happening,
there might be something wrong with your unit. Good chance it was just
random weirdness and you won't see it again.


>I also noticed a few days ago that a loop which was running decayed to
>almost total silence over the course of some fifteen to twenty minutes,
>but the feedback control was definitely all the way to the right.  I've
>read that when more and more overdubs are put into the loops that the
>feedback is automatically scaled back to aout 95%; is that what I'm
>looking at now?

This is a problem that was definitely there on prototypes, and at some
point it was fixed. I have to get Matthias' help here, because some of it
was a software problem, and I'm not sure when it got fixed. I know that
with the mythical upgrade, this doesn't happen. Thing is, it doesn't
necessarily happen with the shipping software either. Matthias, do you know
if this was fixed in the shipping soft?

My uncertainty is because I think there were several different problems
which caused this. One of them may have been the thermal/cut-the-ic-pin
problem. That particular chip handles both the front panel switches and the
feedback knob, so I think that the same sort of conditions that cause the
Undo button to freak out also might cause loop degrading. I never had a
chance to verify that, so I don't know, but cutting that pin certainly
won't hurt and might fix this for you.

The other bit of uncertainty is that there actually was a software upgrade
very early in the echoplex production. You can see the software version
when you turn the power on, the current software will show LD3 3.2. The
first 60-100 units had an earlier version, LD3 3.0.  Unfortunately, I don't
remember what was fixed in this upgrade. Could have been the loop
degradation, but I don't know. What software version do you have Andre?

kim

______________________________________________________________________
Kim Flint                   | Looper's Delight
kflint@annihilist.com       | http://www.annihilist.com/loop/loop.html
http://www.annihilist.com/  | Loopers-Delight-request@annihilist.com