Problem with Samick PM4150 Mixer

If you are experiencing an issue where the QSC RMX 1450 amplifier is not giving any sound when connected to the main output of your Mackie 16 OK mixer, but works when connected to the aux send, here are some possible causes and solutions:

1. Check the main output level on the Mackie mixer. If the level is too low or muted, this can cause the amplifier to not produce any sound. Increase the main output level on the mixer and check if the amplifier produces sound.
2. Check the cables connecting the mixer to the amplifier. If the cables are damaged or not connected properly, this can cause the amplifier to not produce any sound. Ensure that the cables are connected securely and are not damaged or broken.
3. Check the amplifier settings. Ensure that the amplifier is set to the correct input source and that the input gain level is set correctly. You may also want to check if there are any protection modes or limiters enabled on the amplifier.
4. Check the speaker connections. If the speakers are not connected properly or are damaged, this can cause the amplifier to not produce any sound. Ensure that the speakers are connected correctly and are not damaged.
5. If none of the above steps work, there may be an issue with the mixer or the amplifier. You may need to contact a qualified technician to further diagnose and repair the problem.

Remember to always follow the manufacturer's instructions and safety guidelines when working with audio equipmen

he issue you're describing with one of the XLR inputs on your Europort EPS500MP3 mixer amp not working could be caused by several factors. Here are a few steps you can try to troubleshoot the problem:

1. Check the cable: Make sure that the cable is properly connected to the input and that there are no loose or damaged connections.
2. Check the input: Make sure that the input is not damaged or malfunctioning.
3. Check the channel settings: Make sure that the channel settings are set correctly and that the input is not muted or turned off.
4. Check the gain: Make sure that the gain on the input is set correctly.
5. Check the power: Make sure that the mixer is properly plugged in and that the power is on.
6. Consult the manual: Consult the manual for specific troubleshoot and service information for your Europort EPS500MP3 mixer amp.

here is your guide:

http://www.fixya.com/support/t13907270-sony_str_de925_stuck_in_protect_mode

Note : output transistors are embedded inside the Hybrid IC

on some models.

How to Eliminate the Hum and Buzz from your Sound System

Is your sound system making noises you don't want to hear? Try these tips to clear it up!

Instructions


Hum is usually the result of using electrical outlets with different grounds. To verify this, run an extension cord from the outlet that the amplifiers are plugged in, to the mixer.

Remove all the DI boxes and adapters. Connect the mixer to the amplifiers with balanced cables.

Be sure that all your cables and connectors are correctly wired:

Pin 1 shield
Pin 2 + white/red
Pin 3 - black

Note: If the system has an electronic crossover, equalizer, or limiter....you need to keep them in the signal chain to protect the system from damage. Just make sure all the cables are balanced and the pin-out on the connectors is correct.

If your gear doesn't have balanced connections use good shielded cables with the proper connectors.... NO ADAPTORS!!!


If the system still has noise, check each channel on the mixer by removing the input connections. There may be a DI box on stage that is also interacting and causing a ground loop. If that is the case try a different DI and make sure that all the instruments and amps on stage are also on the same dedicated ground as the mixer and amplifiers.


If the hum is gone using the extension cord you will need the have your electrician run a dedicated ground to the mixer and amplifier electrical plugs.

Simple Static Eliminationarcalian.com
Is static causing problems in your reel-to-reel (web) process?



Tips & Warnings

*
Removing the DI boxes, hum eliminators and bad cables may improve the sound quality...unless the DI boxes use very expensive line level transformers (Good ones are about $75 for just the raw transformer inside the box) the signal is being squished thru a $5 instrument level DI box.
*
DO NOT lift the grounds on any of the AC inputs to the amps or the mixer as this could result in electrocution. OUCH!


Hope it helped..

Please don't forget to rate me ..Thanks...

Have a nice day..

Here is a link to the manual:http://www.peavey.com/assets/literature/manuals/00512180.pdf Page8 sections 2 through 4 discusses the LEDs. I think what you arte talking about is the DDT active LEDs. Page 12 specifically discusses this and page 15 notes that Red signifies DDT clipping. Peavey recommends that you don't defeat the DDT circuit and that is good advice as it protects your amp and your speakers. The clipping is not caused by the amp but by the amount and quality of signal being input. Check earlier in your signal chain for the cause.

Make sure you don't have any shorts on your speaker wires or rca cables. Unplug one at a time, the turn on power until it stays green with no protect light, then you know what input is causing the short. If you remove all speaker wires and rca wires and all you have connected is the ground, power(12volts) and remote and it still lights up red/green(in protect mode) then your problem is the amp.

It could be even simpler than that, yes an improper impedance rating on an amp will cause it to overheat, but should function temporarily until it reaches peak temp. If the outputs were blown the protect light should not light up being that they would need to work to cause the protect light to come on. I would double check all of your connections, one small little crossed wire would cause an amp to immediately go into a protect mode.

It probably has shorted output transistors. To eliminate other possible causes, read through the following page.

Amplifier in Protect Mode - Troubleshooting

Let me know if you have any other questions.

disconnect audio inputs and outputs and see if one of those are causing it , if it still does it with all audio inputs and outputs disconnected then there is a problem with the power amp

Unplug the stereo input signal from the amp. If the amp does not do it with the wires unplugged, you may have a problem with the radio sending too much voltage to the input of your amp causing it to go into protect mode. If it continues it is in your power source to the units. Let me know and I'll see what Ii can do. Hope this helps...