I am trying to set up a sunn px2112 mixer(old mixer used by my church). This series of mixers are supposed to be powered but i am not getting anything through the speakers. Are these mixers setup like others as I have speaker cables from the mixer to the speakers(speakers are good). The only way i can make it work is if I connect the speaker cables to an amp. Am I hooking the mixer up wrong or is the amp in the mixer (supposedly 250 watt) not working?
Need pictures of your exact setup. The speakers must be connected to the speaker outputs on the rear of the mixer using correctly wired 1/4" speaker cables(not mic cables) and also not to the main output jacks, and the front panel switches must be set to link the internal amplifiers to the main outputs and not monitor outputs.
None of the jacks on the top panel drive speakers. The ONLY jacks that drive speakers are on the rear panel and are labelled "Speaker Outputs".
Also upper right on the top are the power amp assign buttons. They say MAIN/LEFT and MONITOR/RIGHT. TO get left and right from the two power amps, both buttons need to be down.
Also upper right on the top are the power amp assign buttons. They say MAIN/LEFT and MONITOR/RIGHT. TO get left and right from the two power amps, both buttons need to be down.
Main/Left and Monitor/Right are depressed. Unit acts like the mute button is depressed on all channels but there is no mute button(that I see). Sound graphic lights up when microphone is spoken into but no sound in the speakers. Amps do not seem to be working.
Sound graphic? Do you mean the LED meters? Do the speaker cable connectors look like this? It is entirely possible something has happened too the amplifiers and if so you won't be able to fix it, it will need to go to a repair shop. But if something is blown don't bother spending any money on fixing it just but a separate amplifier to drive the speakers.

any dc on the amp outs?
common fault in these is funky switch contacts in the graphic in out jacks and amp inputs.
if you have some known good 1/4 patches try bypassing the graphic EQ or better yet repatch from the main and monitor out to the amp inputs.
in the process some good quality contact cleaner may well restore signal! if not inspection for bad/cracked solders would be in order.
common fault in these is funky switch contacts in the graphic in out jacks and amp inputs.
if you have some known good 1/4 patches try bypassing the graphic EQ or better yet repatch from the main and monitor out to the amp inputs.
in the process some good quality contact cleaner may well restore signal! if not inspection for bad/cracked solders would be in order.

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If You manage to get the amps working, do yourself a favor and replace those 1/4 speaker jacks with Neutrik Speakons if space inside allows. It will be more standard.
Do the same on the speakers.
Do the same on the speakers.
Thanks everyone, I used an external amp and have a working PA now. I do have static but I can turn the amp down far enough to get most of it. Thanks again.
1/4 phone plug speakers on stage blow a lot of amp outputs. People trip on the cord, pull it out partway, the tip shorts between hot and return. The cheap version of no-short speaker jacks is dual banana jacks. Neutrik Speakons are a lot harder to drill the hole in a panel. Banana jacks are only 3/8 or 10 mm diameter holes, which is a cheap drill.
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