System shutting down due to clipping?

From time to time my HT system shuts off when playing at higher volumes. The Yamaha AV unit is running out of juice and I assume it is tripping off as a self preservation function. I am guessing that the rear surround speakers are the culprits since they are 4 ohm. I am not sure whatload the center channel is.
SO how do I fix this? I do not want to change the AV unit and am not real keen about changing the speakers either. Don't even think of suggesting that I turn the volume down.
For some Yamaha AVRs, there is a setup option to run "6-ohm" speakers (which may work 'better' for your 4-ohm speakers).

Check your manual.

Also check to see what your max volume setting is: there are options to limit the volume and if you don't have that set to max then the AVR may shut down as well.

Check your manual.
Not knowing the receiver or speakers, at least make sure the surrounds are set to small. The fronts also, if the subwoofer handles the bass.
What you're saying is that you refuse to purchase nail proof tires or drive around the nails in the driveway.

If you're pushing your equipment beyond it's limits then the only solution is to purchase equipment that'll do what you want. If you don't, you can expect problems and eventually it'll shorten the life of the AVR and will turn into a self solving problem unless you replace it with another unit that's not up to the task.

Try running the setup without the rear channels and see if it still trips off. This would help isolate the problem. If your center is also 4 ohms then bypass that one as well.
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turn it down, change to a better amp or get different speakers, I can all but promise your problem is beyond a fan or two.
I checked the manual and this newer model AVR does not have a 6 ohm option. The surrounds are set to small and I did dial back on the master max volume setting.
I am not going to replace the AVR since it is fairly new. I will consider changing out the speakers if I cannot get this fixed. I do not want to "turn it down" since the system needs to play at the volume level I want. It is suppose to please me and I am not going to play at a low volume in fear of the system shutting down. If the problem is overheating as Elizabeth suggests then a fan should certainly help. I just have to figure out how to wire one into the system. More testing tonight. And no I wasn't playing it on 11.
Put some more 4 Ohm speakers on that Yamaha, crank it up and show it who's boss.
Make sure you have good ventalation or a fan as suggested. This is most likely a heat problem.

Blueskiespbd, check your manual again, page 20. There is a 6 ohm option, if your receiver is the RX-A1000.
I am not sure it is heat either. The unit in on the top open shelf and doesn't seem hot. What do you think?
I think you need a more powerful amp, more efficient speakers or you should learn the limits of your system.
Just to stir the pot a bit more.

The OP may be able to keep his current AVR and IF it has pre-outs, he could add an external amp.

Couple of choices:
1) 2-channel ext amp for Front L/R speakers - which may 'offload' the AVR enough to drive the remain speakers
2) multi-channel ext amp: 3 or even 5 channel and completely offload the AVR from driving any speakers.

Would be helpful to know which Yammie AVR model the OP has.

I still have my Yamaha RX-V1800 as my AVR for a 5.1 setup. At one point I had my old Carver M-1.0t hooked up via the AVR pres for Front L/R ext amplification, and could go "stupid loud" for all channels.
I have the Yamaha RX 1000. Not sure if it has pre outs as you mentioned. The Sonic Frontiers preamp has a bypass switch so the mains are running off 2 Aragon Palladium monoblocs. The Sub is self powered and the Yammy is also running the center.
Your AVR does have preouts ("Main outs"):

It sounds from your above system setup description that you are using the main outs from the AVR, connected to your Sonic Frontier/Aragons to drive your Front L/R speakers.

If so, then your V1000 is only driving the center and surrounds.

How long have you had this setup? Is the AVR shutting down recent?
I have had this setup about a year. The shut down has only started in the last 2 months and only when I have things cranking a concert dvd. The Snell center is also 4 ohms. The AVR is rated at 105 watts @ 8 ohms. The center is
rated at 90 db sensis. and 50 watt min, 250 w max. Not sure about the Canton surrounds but I do know they are 4 ohm.
I just got off the phone with Yamaha....was only on hold for 50 minutes !! yipeeee. The tech said this AVR can be reset to 6 ohm by holding down the power button and the Straight button during power up. I will try that tonight after work.
This should help and would be cheaper than any other option
if it works.
Maybe the AVR power supplies are is an older model.

If you've had this for awhile and the shutdowns are 'recent' - sure makes the AVR the probable culprit.

Good excuse for an upgrade!! :-)
Well you didn't say the exact full model number.

There was an older RX-V1000 that IS obsolete/discontinued.

The newer Aventage line is the RX-A1000.

Like I said in reply #1 - hope the 6-ohm setting works for you... ;-)

I was able to reset the avr to 6 ohms. At high volumes with dynamic passages it still will shut down. I think I need an extra amp for the surrounds only or else replace the speakers with 8 ohm boxes.
OK , the system still shuts down at concert level volumes. Strange thing since it never use to do that before. It has been reset to 6 ohms but that made no difference.
I may try hooking up the old NAD 2700 amp I had before to see if that would cure the problem. I have to get it back from the guy I traded it to months ago. I still wonder if the AVR is defective. I do hate to ship it back even if it is under warranty.
You NEED to issolate one part at a time. First, however, you should check for dead shorts between speaker wires -wires touching other wires, pos, neg, etc. If it's not that, then you are likely overloading the amps, by too much current being needed to drive the load, and receiver is running out of steam, yes.
You should be, most likley, running all your speakers at 80hz, and letting powered subs handle bass bellow that, with multi-ch movie material anyway - especially with a receiver bassed system, and passive speakers! My experience is that, even with the larger flagship receivers, the amp sections are lacking, and taking full use of your active crossover is going to help your dynamic range and efficiency GREATLY!!! Can't over stress this point enough!
Many people using large speakers tend to try and rund those passive speakers as large (only large active speakers or speakers with powered subwoofer, and large efficient horn speakers, should be tried running full range with HT, especially run by a receiver!!!!), which really taxes the heck out of the powersupplies. Also, they run speakers as large, because they often can't get then to sound good otherwise. My experience here is that is almost always due to placement problems, where there's weak bass response, or a "hole in the response", and such due to bass modes, poor speaker and seating placement setup, at the critical crossover point, especially. (can't replace proper setup foundation).
Like I said, try issolating one thing at a time in your system, by process of elimination. Start looking for dead shorts, crackling sounds from speakers, etc. Then, make sure all speakers are crossed over up higher, and take some strain off the receiver. You can also try switching speakers out for more efficient. Basically, try whatever it takes to figure out the power problem.
You can do it.
"Then, make sure all speakers are crossed over up higher, and take some strain off the receiver."
Not sure what you mean here? The powered sub is has an adjustable crossover but the center and surrounds do not.
The mains are run on the large monoblocks