Hey, I have a LTO 12 channel mixer and the right main mix out isnt working. The left out gets sound but the right isnt working for some reason. Just want to know if theres something im not checking. Not panned, everything is normalized on the board, theres not even a crackle when I check the cable it just seems to be dead. Quick fix? Or **** *** out?
WHo knows? Troubleshoot it.
Separate main faders? Or one stereo fader? Is the fader - whichever type - getting signal at its top end? Is there signal at its wiper?
Look at the op amps in the main section. ANy with unwanted DC on an output pin? ANy getting hot?
Does that mixer have patch jacks for the master section? Like inserts? Does signal come and go through an insert OK?
Separate main faders? Or one stereo fader? Is the fader - whichever type - getting signal at its top end? Is there signal at its wiper?
Look at the op amps in the main section. ANy with unwanted DC on an output pin? ANy getting hot?
Does that mixer have patch jacks for the master section? Like inserts? Does signal come and go through an insert OK?
One main fader google LTO 12 channel For a picture. I hooked it up to my powered pa speaker, the left would make sound the right would not. I tried 1/4 in and xlr with the same result
Googled LTO, and got numerous mixers by Alto (with the first "A" filled in as a triangle) Could you give a serial number or something? Is this a powered mixer with effects, or have I landed on a completely wrong model?
I'm pretty certain it can be mended, but need a bit more information before starting a test procedure.
I'm pretty certain it can be mended, but need a bit more information before starting a test procedure.
If it has main inserts, exercise the jacks with a 1/4" plug. They can be troublesome esspecialy in clubs or bars.
Cumbo, you will have to go inside for this.
My first test inside would be to scope or otherwise monitor the main fader. Is signal getting to the top of both sides of it, and is signal coming out the wiper of both sides of it?
My first test inside would be to scope or otherwise monitor the main fader. Is signal getting to the top of both sides of it, and is signal coming out the wiper of both sides of it?
It has built in effects. I tried the 1/4 inch and nothing works with the right side. Left side fine right side nothing
Does it have a) output equalisers, b) mix insert points (probably three pin jacks, but wired strangely) c) output metering d) headphone amps and e) a model number? (does it seem to you I'm groping in the dark a bit?)
If it's the Zephyr ZMX 124 (possibly) it has four subgroups which have inserts, so probably the main mix does too (the picture quality in the website I've accessed is disturbingly illegible) and it probably gives you a mode of operation bypassing the main outs. I assume the meter says there is nothing coming out of the right hand side too? And that the headphones only work in one ear? (yeah, I know, but it's worth checking before opening the thing up). If you don't have a 'scope, build a probe lead to a jack , and plug it into a guitar amp; it won't tell you much about the quality of the sound, but is good for checking whether it exists or not, and the manufacturers build the inputs difficult to blow up, having worked with guitarists before.
Hm, I've found a user manual for an L-12, with block diagram; is it that one?
If it's the Zephyr ZMX 124 (possibly) it has four subgroups which have inserts, so probably the main mix does too (the picture quality in the website I've accessed is disturbingly illegible) and it probably gives you a mode of operation bypassing the main outs. I assume the meter says there is nothing coming out of the right hand side too? And that the headphones only work in one ear? (yeah, I know, but it's worth checking before opening the thing up). If you don't have a 'scope, build a probe lead to a jack , and plug it into a guitar amp; it won't tell you much about the quality of the sound, but is good for checking whether it exists or not, and the manufacturers build the inputs difficult to blow up, having worked with guitarists before.
Hm, I've found a user manual for an L-12, with block diagram; is it that one?
Yes it is the L-12. The headphones work in both ears. I have plugged it in to my behringer PA speakers with a mic plugged into channel one. Main out left works fine, main out right will not even hum. Alto L-12 12 Channel Live/PA Mixer With Digital Effects
thats the mixer
thats the mixer
Now, according to the block diagram, phones feed (in "main mix" mode) is from after the volume control, after the insert points. This means there is exactly one op amp, an attenuator switch, and a minimum of wiring between it and the outside world. It's possible that someone's done something stupid, like plug a power amp output into a console out, but I'm betting on the -10/+4 switch having some bad contacts (which would not stop it if the circuit were as the diagram states, but I don't trust it as a reliable guide to the actual electronics, just the flow path).
The block diagram is in a pdf I downloaded from the web; it's too big and complicated for a worthwhile attachment. If you PM me your eMail, I'll send it you.
The block diagram is in a pdf I downloaded from the web; it's too big and complicated for a worthwhile attachment. If you PM me your eMail, I'll send it you.
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