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parametes changing by themselves - PLEASE HELP!!!!!

Posted: Sun Aug 10, 2008 3:10 am
by i_rob
Hi everybody

I have recently bought an LP stage II and a few days ago I have noticed that when I am in track mode (my prefered knob mode), active parameters in a preset tend to drift. For example, if the active parameter in the OSC section of a preset is OSC 2 frequency, than a few seconds after I start playing, Osc 2 frequency starts to drift and after 30 seconds or so it is completely out of tune. This drift occures in all sections of the synth and can be seen easily in precision mode where the numbers change though no knobs are turned. Sometimes even the LEDs near the knobs show the drift. As I mentioned before, this only occures in track mode and it seems to be partly eliminated when the knobs are turned all the way clockwise.

Amos or anybody, Please Help!!!!!!!!!!!!!!!!!!!!!

Thanks

Ido

Posted: Sun Aug 10, 2008 8:15 am
by Maskin
Check if your Phatty is in a grounded power strip.

Posted: Sun Aug 10, 2008 11:22 am
by jgirv
...is the LP fully warmed up (15 minutes) ? ....

Posted: Fri Aug 15, 2008 6:02 am
by scaremi
Hi,
I had the same problem with my LP SE OS 2.0
Please help
Thanks in advance.

Posted: Fri Aug 15, 2008 11:13 am
by dlearyus
first thing i would check is grounding or noise in your AC outlet/supply

Posted: Tue Aug 19, 2008 2:37 pm
by Notlob
Hi folks - new analogue synther + LP SE OS 2.0 owner here; I seem to be having the same problem as a couple of others - LEDs advancing on their own, especially the mod knob, which will go from completely anticlockwise to fully clockwise in 30 seconds (the filter knob LEDs flicker backwards and forwards too). This doesn't happen at all when using headphones, but intermittently with both my Behringer keyboard amp and when connected to the home cinema aux socket.

When it's playing up, just touching the jack to the amp's case will trip the preset switch from amber to red immediately. I assume it's some rogue charges screwing things up as suggested - very frustrating!

I've tried multiple wall outlets and mains adapters (all earthed/grounded) to no avail. Would a special smoothed adapter or something do the job, or do I need to get my house's wiring checked?!

Thanks in advance, Andy

Posted: Wed Aug 20, 2008 8:21 am
by scaremi
Hi,
I checked all the connections of my LP and I did not find any problems. But this flaw continues and is very annoying. I ask for help Amos to give a solution to this problem definitively.
Thanks in advance.

Posted: Thu Aug 21, 2008 4:09 pm
by Notlob
Sorted - the travel adapter I was using to convert US to UK plugs had a plastic earth pin! Typically, the other 3 I'm using would have been fine!

Andy.

Posted: Sat Aug 23, 2008 6:02 am
by scaremi
HI,
there is someone who can give a solution to this problem? All of my LP connections are ok.
Regards
Emidio

Posted: Sun Aug 24, 2008 9:08 pm
by voodoochilimoog
Can you actually see the LEDs follow the change in parameters? This never happened with my Stage I but it sounds very odd... I hope it is not a common problem in the SE II's.

Posted: Mon Aug 25, 2008 5:36 am
by Voltor07
Did you try moving the LP to an outlet on a different circuit? Perhaps you have a bad ground on that circuit...

Posted: Mon Aug 25, 2008 5:47 am
by scaremi
Yes,
i see the LEDs follow the change in parameters.
The problem is not the case if the "pot. section osc." is completely rotated counter-clockwise
I have a LP Stage I with OS 2.0 .
At this point I believe that it can be a hardware defect on many LP.
But I would to know the cause and the solution of the problem.
I thank in advance someone who can help me.
Regards
Emidio

Posted: Mon Aug 25, 2008 5:52 am
by scaremi
Thanks Voltor07,
I tried to move to an outlet on a different circuit but the problem remains. I did many other tests before writing on this forum.
Regards
Emidio

Posted: Mon Aug 25, 2008 8:51 pm
by Tangsonghe
I've been in correspondance with Amos about this
problem too. I haven't solved it and noted it on the
forum a few months ago. Amos gave some good
tips that I didn't get to try and now my Phatty is
temporarily in storage.

It appears that noise is getting into the ground plane of
the phatty and the RAC sensing algorithm interprets it
as a knob change. I'm not sure why this doesn't happen
with the old OS. For me it is intermittant and appears to
be worse when I run the phatty into outboard FX (DI or
no DI), though it can happen if the phatty is running standlone
with only headphones plugged in.

Posted: Mon Aug 25, 2008 8:58 pm
by Voltor07
Perhaps you have a bad ground period...I dunno. I'm out of ideas... :shock: