I have a Yamaha dsp ax1 when I turn the volume up the amplifier cuts out

Check if the sound comes from a digital source like an optical cable or the one that generally the color is orange (not the common red and white, nor the yellow terminals) then check also if this ocurr with certain music. Let me know

Just throw it away and buy a new one.

Check the output transistors for leak.

The fact that sound appears at max volume means that it is getting past and through the pre-amp stage. So it would appear to be in the main power amp stage the problem. It would depend what drives the channel, but if it's transistor driven I would suspect one of them.

Is this new equipment or a new problem on working equipment?

Register and download the manual for free at retrevo.com

http://www.retrevo.com/support/Yamaha-DSP-AX1-Amps-manual/id/319bh827/t/2/

See Troubleshooting Page 79

Impedance Selector in between settings

Generally speaking, an amp protects itself from heat, shorts, overloads and operator exuberance by refusing to turn on or stay on.

Overloads can be from excessive periods of high output or marginally low impedance loading by the speakers; and shorts would be wiring issues or a speaker blowing up.

You should be able to feel if it's hot. WHY is it overheating? Make sure it has sufficient ventilation on all sides and that vent holes are not blocked by dust balls. Ensure the fan (if equipped) is running as designed (some only operate on demand). Clean dust and debris from it.

If the amp comes back on after cooling, you're lucky. They only have so many self-protection cycles in their lives so continuously resetting or cycling their power without addressing the cause can do more harm than good.

If it protects immediately on a cool power up you should disconnect the speaker connections and try it 'naked'. If it comes up then diagnose which lead(s) are shorted. If it does not come up the problem is internal and should be left to an experienced and competent hands-on tech.

Are all the speakers turned off (set to None) in the speaker menu.(except the sub)?

2 channel direct analog stereo may still work, but any surround modes will use the speaker settings and the full DSP digital section.

Check also the input mode isn't incorrect - although if the sub is wired correctly and gives sound this can't be whats wrong.

I have one like it in my shop

The main power transformer has gone bad

Yamaha has them in stock

My bet is a faulty electrolytic capacitor! Don't know which. but would look around the circuit of those stages.

disconnect the cabel of left channel from your amp disconnect the cabel of right channel and put it in place of left channel if the problem goen your problem is in left speaker itself (cabel or speaker).if the problem excit the problem will be in amplifier output stage

does the speaker relays work?