Muff's Modules & More

prototek · Posted: Fri Jul 08, 2011 12:00 pm Post subject: Lexicon LXP-5 Problems...

I have an LXP-5 with the dreaded "dirty pot" problem. It seems the pots are so dirty that it's not even letting the signal pass through properly. What I want to know... Are there any ways to fix these LXP units or are they headed to the junkyard once this happens? The pots' posts are soldered directly into the PCB. If anyone has any info or experience combating this problem, I would love to hear what you to say.

-John

MindMachine · Posted: Sat Jul 09, 2011 1:37 am Post subject:

Same boat here. Mine has encoders that cause rumble and feedback and skipping functions/presets, etc. I think they may need new encoders and that replacement is more than (or close to) a new used unit would cost. I asked a guy who specializes in upgrading lesser Lexicons (his name is on my work computer and escapes me at this time) and he basically said we are screwed. I had a tech clean mine up so it worked better for about 2 months. And then it went noisey glitchy psycho runaway feedback doom machine again (in a shitital way). zombie

I hope someone has better news/alternatives. Dead Banana

haiku-ish · Posted: Sat Jul 09, 2011 1:55 am Post subject:

i've sprayed some contact cleaner into the encoders several times, and now the encoders are ok in my lxp1/5

prototek · Posted: Sat Jul 09, 2011 4:03 pm Post subject:

Thanks for the feedback guys.
Theoretically... Would this problem be solved if one unsoldered the original pots (and encoder) and put in new replacements? Technically, I don't see why it wouldn't, but I'm no expert. BTW, I tried Caig DeOxit on mine and there was no change.

Does anyone know if this happens to all LXP units after a while, or just ones that have been exposed to too much dust, etc? I'd hate to think these things are doomed from the start. I think they're really cool little FX boxes.

-John

MindMachine · Posted: Sun Jul 10, 2011 2:00 am Post subject:

Let me check my files at work. Hopefully I can at least put you in touch with the tech who specializes in these boxes. From what I remember he said that we are screwed w/ the encoders. I wnat another LXP-5 bad too. My LXP-1 still works fine, but my LXp-5 is freaking psycho. An effect will be sounding great... I fade down volume... go get a beer, put on some Heldon... listen for a bit... fire up my board to record and CRKKK crrrk CRKKK crrkkkk. The LXP-5 has gone insane. Crap encoders. Then I click the pot over to remove the CCRRRKK but then it does not affect anything. The horrible noise is gone and so is functionality... until next fire up.

I feel your pain. I will report back.

prototek · Posted: Sun Jul 10, 2011 1:36 pm Post subject:

Thanks Mind. I just heard back from a tech. He tells me that he can fix these. He generally replaces all of the front panel controls, then replaces the caps and also installs new jacks (only if needed). He says it will only cost $50. I think that's an incredibly good price (even though it's about a quarter of what the LXP is worth) for what he does. I'll keep you posted about my findings with him.
My only hang-up is I hope that switching out the pots and encoder will indeed fix my unit. Mine is mega-screwed up... It passes no sound, and no matter what I plug into the input the overload light comes on. The only way I can get any sound at all is by forcefully pushing the input knob CW. When I do that a very faint, distorted sound comes through (barely). I'm pretty sure it's all down to the pots/encoder. Any of the symptoms I described sound typical for a unit with busted pots? I just want to get some kind of confirmation before I throw down another $50 on it because at that point I'll have spent the same amount of money that I would buying a half decent unit like a Lex MX400. Thanks guys.

-John

MindMachine · Posted: Fri Jul 15, 2011 12:01 am Post subject:

That sounds like quite a deal. Can you PM me the tech info so I might give it a try? I found another local LXP-5 for $ 150.00 which seems a bit steep. I really liked mine before it went senile. I think the encoder swap will cure your ills.

I was unable to find the tech who I had mentioned before - I deleted the info I guess. Moot now.

MindMachine · Posted: Sat Jul 23, 2011 1:32 am Post subject:

Edit bump -

This is the dude from Tape Op:
http://www.audioupgrades.com/upgrades/upgrades_signal_processor.htm

He does not do the encoders though. Just audio upgrades (duh)...

He is pretty revered for upgrading the signal paths of these 90's Lexicon units. I have not done any of these yet, but the Tape Op forum is pretty high on the guy. He is cool and will answer any questions regarding the units or upgrades.

So if they work, he makes 'em work better. thumbs up

John Nonjohn · Posted: Sat Jul 23, 2011 11:50 am Post subject:

I have a LXP-5; I guess all these guys suffer from the scratchy pot/encoder problem. My LXP-5 is in ok shape, but the input pot, specifically, is very noisy.

My solution--I found a nominal spot for the input level (at the 10:30 position), where the pot doesn't scratch, and I set the input pot and forget about it! The output pot, of my LXP-5, is set at maximum. These settings work for me--for now!

aumgn · Posted: Sat Aug 27, 2011 3:29 pm Post subject:

its a great shame this , i had 2 x lxp5 over the years and 1 now and yeah , it has that bullshite problem they all do , the encoders fail , send out sporadic info into the fx processor and it auto switches programs / fx and acts like shite.I am currently looking for a tech in the uk to sort this.I personally advise using the lxp5 sound diver , its really very cool.A fix ? i need one as does about every lxp5 owner on the planet.Switch cleaner. . . . now it could be as simple as that.

consumed · Posted: Wed Nov 02, 2011 11:50 am Post subject:

heads up--

i have an (edit: lxp-5) that's been out of commission for a long time. i have a probable source for these encoders; however, you will not be able to use the original knob due to the spline shaft. let me know if this is interesting, and either ill point you to the source, or i will pick up some extras and pass them along to you.

consumed · Posted: Fri Nov 11, 2011 5:37 pm Post subject:

so i have/had both problems: noisy in/out/mix pots, and something funky going on with the three encoders. id switch to a preset and start changing the adjust, but the effect might come and go.

the pot noise from the in/out pots was so loud the overload light would come on. i spent five minutes exercising the pots and they are nearly silent now.

i ordered a handful of encoders but have not yet installed them. they are supposed to be exactly the same part, except the shaft is different. it is a split/spline shaft for push on knobs. i will need new knobs or to modify the existing knobs. ill report back on my progress.

MindMachine · Posted: Sun Nov 13, 2011 4:26 am Post subject:

Please let us know. Just last night I was thinking of dumping my -1 and -5. Love/Hate.

Ankh · Posted: Sun Nov 13, 2011 6:24 am Post subject:

Hmm, would this encoder work on a LXP-15 as well? I have one with a failing input encoder. waah

consumed · Posted: Sun Nov 13, 2011 12:05 pm Post subject:

I installed one of the encoders in the lxp5 and its working perfectly. The shaft is a little shorter and spline (not d shaft). I havent figured out if im going to locate new knobs or mod the old ones. Im going to install the remaining two encoders probably today, which will leave me with two spares.

I dont know about the lxp15, sorry

passnthru · Posted: Thu Feb 09, 2012 7:04 pm Post subject:

I've had a few of these units for a while. Dirty pots and the encoder problem are common but not insurmountable. Perhaps these can give a hand.

https://groups.google.com/group/rec.audio.pro/browse_thread/thread/e9f a387d9f935456?hl=fr

https://groups.google.com/group/rec.music.makers.synth/browse_frm/thre ad/fa732aeb15ae8fca/0b4aacc0d0539a4b?lnk=st&q=lexicon+LXP+problem&rnum =54&hl=en

I'm partial to using the MRC as a controller so once you find a setting on the encoder that works it can do well. There are some software editors that may be useful as well. MRCedit comes to mind. I have schematics and manuals on pdf for the lxp1. You can PM me if you'd like them emailed.
consumed, I'd love to know where you got those encoders if you could.
JP