I will like to know what will cause my qsc mx1500a to sound as if my speakers is faulty.. this only happen when I load and play the two channels at same time.. if I play any one channel it will sound very well
I can't think of another circuit that can cause that problem with this amplifier...clean the switch or check if the contacts are ok...open the case an have visual inspection in that area.
This is a class-G amp from the description, if each channel is clean at full power it means the power supply is failing to provide enough power for both channels, or the protection circuitry is cutting in and out for some reason (thermal?). Checked the fan is running? Vacuumed out the dust filters recently?
is a while I did.nt give it a dust out.. let me dust it out and clean out the bridge switch
The thermal protection won't get into action before a few minutes have past anyway.
It's using two batteries of capacitors that are providing a virtual ground for each amplifier so filtering is independent ...
It's using two batteries of capacitors that are providing a virtual ground for each amplifier so filtering is independent ...
No, because each channel has it's own capacitors.They are actually in a special configuration used only in QSC amplifiers where they provide a virtual ground to the speaker and amplifier .It's a bullet proof system.If you can hear each channel very clear at max power , there's no problem with the filtering.
when you say "this only happen when I load and play the two channels at same time" is it distortion? or is it that it does not sound right?
distortion is self evident but the other condition, doesn't "sound right" could be anything from phase/polarity problems to response anomalies from bad grounds on filters or simply bad solders.
peel the cover clean out the dust bunnies and do a close inspection of all solder points around input connectors and other general things like pulled/misfitted looms or cables or any stress cracks on heavy components.
distortion is self evident but the other condition, doesn't "sound right" could be anything from phase/polarity problems to response anomalies from bad grounds on filters or simply bad solders.
peel the cover clean out the dust bunnies and do a close inspection of all solder points around input connectors and other general things like pulled/misfitted looms or cables or any stress cracks on heavy components.
it will play good,, is just that it will sound as if the speaker knock when the bass hit
what sort of speaker and cabinet? these amps have enough nuts to hurt even good drivers when misused.
and likely a language thing but i'm thinking your drivers are running out of excursion (hitting the mechanical limit) this could be helped with EQ or possibly a high pass filter depending on the box design the drivers are loaded in.
don't be shy the more details you supply the better and quicker we can figure out what's likely happening.
and likely a language thing but i'm thinking your drivers are running out of excursion (hitting the mechanical limit) this could be helped with EQ or possibly a high pass filter depending on the box design the drivers are loaded in.
don't be shy the more details you supply the better and quicker we can figure out what's likely happening.
after a shot of scotch and some contemplation on the part in the original post where you said each channel is ok on it's own....are you certain your speaker loads are in phase with a pulse test?
it will work very good on any one channel at a time even when I drive it to the max.. , the noise will start when I start to drive it with each channel loaded
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