I just got hold of a used Lexicon MPX-1 and I am not getting signal through it at all. It's in pristine condition, so I think it's ME and not the unit.

I'm going from PSG to preamp input to preamp line out (both A & B) to Lexicon A & B inputs; then from Lexicon A & B outputs to amp A & B imputs. All input/output levels on the Lex are sufficiently high to get a signal. I'm using all GeoL cables that are known to be working. There is an LED meter for viewing headroon on the Lex, but I get no signal whatsoever. This LED, etc., all seem to work fine during startup/initialization. I think I like knobs better than presets...

Anyway, if I bypass the Lex and go straight from PSG to preamp to amp, I have no problem. So, I know that somehow it's the Lex. I've read the manual extensively, but I can't see anything missing or incorrect in the basic setup parameters. Besides, I might expect to get a CRAPPY sound until I learned how to tweak it, but not NO sound at all.

I should say also that I've tried connecting the Lex through the effects send/receive of the preamp, but no go.

I'll be calling Lexicon product support in the morning, but this thing is driving me nuts right now. I 'spect that the answer lies with someone who has knowledge of this particular unit. However, I am open for any and all suggestions from this most excellent group of advisors.

Thanks very much, and here's hoping to have the walls reverberating loudly by nightfall,
Steve

[This message was edited by Steve Feldman, who is now beginning to learn the true lesson that too much gear will curtail or halt your playing time, on 06 February 2000 at 11:06 AM.]

I have both the MPX-100 and an LXP-5. I'll assume for the moment that your unit is like the two I have, since Lexicon input/output arrangement is pretty consistent amongst the various models, I think.

Since you are not able to get an input level indication from the unit's LEDs, then it's most likely that no audio is getting into the thing and not that it's ignoring it. Here are some suggestions:

1. Make sure you haven't made the kind of mistake I'm sure I'm fully capable of doing -- getting the inputs and outputs of the unit backwards (putting your preamp output into the MPX-1 output, and connecting the MPX-1 input to the preamp return). Replacing this reversed effects loop with straight cables alone will still work because the cables don't know or care which way the sound is going.
2. Check the unit by trying to send audio directly into the unit from your PSG (a booster like the Steel Driver II would help). You'll have to crank the Lex's input knob way up, but I think it will respond (the MPX-100 has no trouble with this, in fact it works as a preamp for me). You can do this test without the Lex's output connected to anything - just look for the green signal LED to light. If this works, then there's some problem in getting the output of your preamp into the MPX-1.

If you still get no LED response, I'm stumped. If you do, you'll somehow need to check the preamp line out from your amplifier for signal, though from what you've said it seems ok.....

Give the above a shot. Then take two aspirin and call me in the morning.

[This message was edited by Bill Llewellyn on 06 February 2000 at 01:56 PM.]

Thanks for the help. I may be back for Round II.