need some help with a receiver going into protect mode .. [Archive] - Audio & Video Forums

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stan2
06-10-2005, 05:59 AM
lately my receiver (Integra DTR7.1 - same as onkyo 787, i think) has been kicking off in protection mode whenever i play something semi-loud like action movies. i can start it right back up but have to keep the volume turned down. i am running only the center channel with the receiver, with no rear speaks connected, and using preouts to an amp for left and right. i have a powered sub out of the receiver's sub out jack. it is running 5.1 setup (even tho there is really only the center being driven by the receiver). the volume is not excessively loud; what could cause an overload or whatever to trip the protection at normal movie listening levels? i assume the rear channel amps are on, but no speakers being driven. is that the reason? manual doesn't cover this.. thx!

any other onkyo owners with a 787 model had this problem?

shokhead
06-10-2005, 06:18 AM
Try unplugging it for 5 min. Also have you dedusted the insides?

stan2
06-10-2005, 06:52 AM
thx.. i haven't unplugged; just turned it off for a few min. it always starts back up fine. maybe unplugging would reset something? as for de-dusting... haven't done that, but worth a try. i just wonder if there is some weak link in the internals. bad cap or something.. but i'll try your suggestions this weekend. if not that, there are a couple service centers in town.

JSE
06-10-2005, 12:10 PM
A couple of suggestions,

- check for phase

- make sure no stray copper strands of wire are creating a jump between the speaker posts and receiver post.

- check for damage to any and all cables.

JSE

bjornb17
06-10-2005, 01:01 PM
A couple of suggestions,

- check for phase

- make sure no stray copper strands of wire are creating a jump between the speaker posts and receiver post.

- check for damage to any and all cables.

JSE

i was going to suggest these as well. I would say that the stray copper strands could be a likely cause.

in addition to those, are you trying to power speakers that have a lower impedence than what your receiver can handle? For example: 4 ohm spekaers on 8 ohm receiver?

shokhead
06-10-2005, 03:00 PM
Would a stray strand make it shut down or just sould like crap?

Geoffcin
06-10-2005, 03:47 PM
Would a stray strand make it shut down or just sould like crap?

You would be shorting the amps terminals. I did this once on a 400watt amp, luckily there was a 8amp fuse that fried first.

Woochifer
06-10-2005, 03:57 PM
A bad connection somewhere on the speaker wire is a likely problem here. You don't want any stray wiring that ties the terminal polarities together -- it will throw the amp into protection mode. If no rear speakers are plugged in, then no current gets drawn, so that should not be an issue.

You should also check the impedance selector switch (if the receiver has one) and see if it works better with the selector in a lower impedance position (basically, it lowers the voltage available to the power supply as an extra protection measure when using low impedance speakers, which can more easily overwork and overload the power supply). Even if your center speaker has a nominal impedance rated at 8 ohms, it can still have fluctuations in the impedance that presents more of a load at particular frequency ranges

Since you only plug the center speaker into the receiver, I would also see how the receiver reacts with the center speaker turned off. If it still shuts down, then you should try plugging the receiver into a different circuit. Fluctuations in the household current can also kick the protection mode in.

If the receiver still shuts down after all of this, then you probably need to have it looked over by a repair technician.

cam
06-10-2005, 06:08 PM
I doubt it is a stray strand of speaker wire. I say this because you say it only shuts down when the volume gets semi loud. A stray strand would put it into protect at any volume.

popolz
06-10-2005, 10:04 PM
if the strand isn't touching the back of the amp (but it's close) it will need a little more power to "arc" and the amp will go in protect mode...

I did the mistake when I got my amp before Christmas :o

shokhead
06-11-2005, 05:16 AM
I doubt it is a stray strand of speaker wire. I say this because you say it only shuts down when the volume gets semi loud. A stray strand would put it into protect at any volume.

Plus it wouldnt sound ok,right?

cam
06-11-2005, 07:18 AM
Plus it wouldnt sound ok,right?
If you have a stray strand everything will sound great, but if that stray strand touches either another terminal or the back of the amp it will shut down. I don't believe if a strand is close that it could arc when the volume goes up but I guess it could be possible. I personally think it is smart to use banana plugs with the plastic boots so a stray strand would be impossible.

shokhead
06-11-2005, 08:11 AM
I must have done something right because thats what i did on both my Denons.

stan2
06-12-2005, 08:49 AM
lot of tips here. i ck'd for a stray strand on speaker wire.. nothing apparent there, but maybe there was something before i pulled them out of the terminals, re-twisted, and re-inserted. maybe i'll put on some bananas just to be more sure.

haven't cracked the receiver open for dusting. i will as a last resort if messing with the wires doesn't work. speaker impedence should be ok. speaker is 8 ohm, so that is ok.. maybe the speaker is faulty internally? i'll swap it with another center channel to see if that one runs at hi volumes. if not wires and not speaker, seems the problem is the receiver internally, so i'll go there next..

again - thx for the advice on this. it'll be nice to have the thing volume up to normal neighbor window rattling levels... :D

Astro
06-21-2005, 05:05 AM
that sounds very much like what happend to a mate of mine.
It sounds to me like one of your speaker wires are dogdy,
what ide sugest is take one speaker out at a time and play it at the volume it cuts out at and see. Start with the front left ( if it still does it , insert wire back in and start on the right) Soon youll come to the wire that is cause the prob and you will know beacuse one the wire is out the amp wont shut off. Replace wire.
Of course if this dosnt work check that no wire at all is crossing over and touching other wire.
If it still does it , ide say your either playing it too loud, or the ohm dosnt match that of the speakers properly.

hope this helps