Yamaha 795a shutting off [Archive] - Audio & Video Forums

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brian_tr
12-02-2004, 01:09 AM
I was watching the CMA awards last night and my 795a starting shutting off. First it did it and I turned it back on and it played for about 15 minutes and shut off again. After that it would shut down a few seconds after turning it back on. I was not playing at loud volume. I felt the top of the unit and it was not overly hot. Any ideas on what might be wrong?

kexodusc
12-02-2004, 06:51 AM
I have no idea, my old 795a was doing that for a while and it turns out the power button on my universal remote was being depressed underneath the cushion of the couch...scared the hell out of me.

Check all your speaker wire connections on the back to make sure a small strand isn't touching another wire...hopefully some of the others here can offers some better advice. Good luck.

tlax25
12-02-2004, 07:19 AM
I'm no expert at all, and have never used a Yamaha product. However, a number a years ago I bought the top of the line Sony Theater receiver. After about three weeks of using the receiver, it started to shut-down on me all the time. After much research and talk with so called "audio" experts, I found out that the receiver was not compatible with my speakers. Meaning the receiver ran on a different ohm (if that is the correct term) than my speakers, causing the receiver to shut down. My only option was to replace one or the other. I replaced the receiver. Just something to look at.

Woochifer
12-02-2004, 02:47 PM
First thing to try would be to simply unplug the receiver and let it sit out for a few hours before plugging it back in. If it still shuts down, you should plug the receiver into a different circuit and see if it still does this. As kex mentioned, look at the connections and make sure that nothing's wrong there. Loose wiring can easily cause the receiver's protection mode to kick in. I would also try swapping out a couple of speakers in at a time to make sure that nothing in the speaker is causing a short. If none of this works, then it might be time to decide between a new receiver or a repair job.

Woochifer
12-02-2004, 02:54 PM
I'm no expert at all, and have never used a Yamaha product. However, a number a years ago I bought the top of the line Sony Theater receiver. After about three weeks of using the receiver, it started to shut-down on me all the time. After much research and talk with so called "audio" experts, I found out that the receiver was not compatible with my speakers. Meaning the receiver ran on a different ohm (if that is the correct term) than my speakers, causing the receiver to shut down. My only option was to replace one or the other. I replaced the receiver. Just something to look at.

A lot of Sony receivers have had problems with driving low impedance speakers (that what the ohm rating refers to). It's not really a compatibility issue so much as whether the receiver can handle the drain that a low impedance speaker puts on the power supply. Lower impedance speakers make it easier to overwork and overload an amplifier.

Most receivers have an impedance switch at the back of the unit, and the default is normally for 8 ohm speakers. The 4 ohm position lowers the voltage available to the power supply as a protection measure against the kind of shut down that you experienced. A lot of it could also have to do with where Sony sets the protection mode. Receivers shut down before the load on the power supply is so great that it causes permanent damage. Some receiver makers are more conservative with when the protection mode kicks in.

Altogether though most receivers recommend that you use no more than one pair of low impedance speakers at a time. Some of them can actually drive a full 5.1 set of low impedance speakers, while others will shut down if you use more than one pair at a time.

brian_tr
12-03-2004, 03:03 AM
I have Paradigm: Cinema 90's hooked to it. I have had them for several months without a problem. I checked the ohm swich and it was on 8. I changed it to 4. It is still shutting off. Sometimes plays for a few hours and sometimes for a few minutes. I have checked all the connections. Volume seems to have nothing to do with it. Is there a fan or something that might have quit working?

kexodusc
12-03-2004, 04:23 AM
There is a fan in the 795a, but it typically only engages under stressful conditions, and the Cinema 90's aren't really all that difficult to drive. I use to take me an hour of cranked, party level music (ie: the volume knob at 12 or 1 o'clock) to get it to kick in.

I'm thinking at this point it might be in your best interest to take it into a technician. I would change the ohm switch back to 8.

LEN DOG
12-03-2004, 04:59 AM
I had the same problem with my rx v1400.I only had it a month got sick and tired of popping a movie in and 30 minutes into it would shut down. So i returned the unit and got a new one and it hasn't happened again.

brian_tr
12-03-2004, 12:49 PM
I had the same problem with my rx v1400.I only had it a month got sick and tired of popping a movie in and 30 minutes into it would shut down. So i returned the unit and got a new one and it hasn't happened again.


I have had this unit for several years. I used to drive the monitor 7 series. I have a 1400 now for them. I have had it on all day now with my PVR on pause and it has not kicked off. Kinda of wonder if it is getting a signal from something else. Might put a something over the sensor just for kicks.

brian_tr
12-07-2004, 03:38 PM
This thing is driving me crazy. I though it was going to be all right. It worked fine for a few days and now it is doing it again. I noticed just before it turns off the display on the stereo dims way down.