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aarond
09-15-2006, 02:36 AM
I have an Onkyo receiver that I have wanted to get fixed for a couple of years. Now I have a Hafler P500 amp that has the same problem on one channel sometimes. The Onkyo doesn’t work at all but it was on for several days before I noticed the problem so I’m not sure how the problem progressed.

They both have only a VERY slight amount of output. It’s almost as if the tape 2 loop on a receiver is on but not hooked up. This small amount of output at least lets me know that nothing is shorted out on the external connections.

Is this type of problem indicative of anything in particular?

The first person to tell me how to fix this cheaply myself gets a 6 pack of their choice. I wish it were that easy…

Thanks again,
Aaron

bogie
09-15-2006, 02:54 AM
I'll betcha that it's a fuse that's gone awol... If the P500 is like my DH-500 at all, the fuse is accessible from a little finger knurly dealie (technical term, of course), from the rear.

> I have an Onkyo receiver that I have wanted
> to get fixed for a couple of years. Now I
> have a Hafler P500 amp that has the same
> problem on one channel sometimes. The Onkyo
> doesn’t work at all but it was on for
> several days before I noticed the problem so
> I’m not sure how the problem progressed.

> They both have only a VERY slight amount of
> output. It’s almost as if the tape 2 loop on
> a receiver is on but not hooked up. This
> small amount of output at least lets me know
> that nothing is shorted out on the external
> connections.

> Is this type of problem indicative of
> anything in particular?

> The first person to tell me how to fix this
> cheaply myself gets a 6 pack of their
> choice. I wish it were that easy…

> Thanks again,
> Aaron

mikebw
09-15-2006, 04:00 AM
A fuse may be part of the problem, but they are designed as safe guards when something else goes wrong first. So, I would bet there is something else goig on as well, not that I can really help you figure that out myself.

Aaron??

> I'll betcha that it's a fuse that's gone
> awol... If the P500 is like my DH-500 at
> all, the fuse is accessible from a little
> finger knurly dealie (technical term, of
> course), from the rear.

envisionelec
09-15-2006, 10:18 AM
> A fuse may be part of the problem, but they
> are designed as safe guards when something
> else goes wrong first. So, I would bet there
> is something else goig on as well, not that
> I can really help you figure that out
> myself.

> Aaron??

*snork* *snuzzle*

Huh, whuh? Hey, I was sleeping...

Speaker Relays. Replace them or open up and burnish the contacts.

The End. Back to bed.

bogie
09-15-2006, 12:02 PM
The fuse I'm talkin' about is designed to act as a safeguard in event of Drummeritis...

> A fuse may be part of the problem, but they
> are designed as safe guards when something
> else goes wrong first. So, I would bet there
> is something else goig on as well, not that
> I can really help you figure that out
> myself.

> Aaron??

bogie
09-15-2006, 12:03 PM
Check the fuses first... When I blew one, that was the exact symptom.

> *snork* *snuzzle*

> Huh, whuh? Hey, I was sleeping...

> Speaker Relays. Replace them or open up and
> burnish the contacts.

> The End. Back to bed.

aarond
09-15-2006, 12:41 PM
I'll take a look at that...

In the case of the Onkyo, wouldn't it be odd to have both channels go out at the same time. That old Hafler is another story. Definitlely worth looking into before I send either out.

Also would temporarily bypassing the relays be reasonable? I think I would do this w/ a "junk" speaker

Thanks,
Aaron

> *snork* *snuzzle*

> Huh, whuh? Hey, I was sleeping...

> Speaker Relays. Replace them or open up and
> burnish the contacts.

> The End. Back to bed.

aarond
09-15-2006, 12:43 PM
I took the Onkyo apart and looked at the fuses. I will do this again since it has been at least 2 years. I also got a diagnostic code on the Onkyo as well...

aarond
09-15-2006, 03:05 PM
The Hafler is intermittnet so I do not think it is a fuse, I will check the fuse and related connections though. I've been looking for an excuse to open this thing up. It smells like "old people's house" when the fan kicks on. Probably stored in a basement for quite some time.

I will use a meter to check the Onkyo fuses since I am sure it was only visual last time.

Shiner is cheap here (KS), thanks for not going too primo (or even importd for that matter). I hardly ever buy in 6 packs it since I drink a fair amount of it when I'm out bcause of the price. Damn good beer for the $$.

Later,
Aaron

envisionelec
09-15-2006, 03:25 PM
> The fuse I'm talkin' about is designed to
> act as a safeguard in event of
> Drummeritis...

Eh, when you open a fuse the circuit is no longer complete. I would like to see how a speaker can still have a "tiny amount" of output with an open speaker fuse.

aarond
09-15-2006, 03:29 PM
I was wondring the same thing. I'm no expert (there's a reason I am asking for help) the solution seemed simple and cheap and I would be more than happy if it works (but confused as to why it worked). I need to open these up anyway so I up for any ideas while I'm in there.

Aaron D

bogie
09-16-2006, 02:24 AM
I dunno why... But if you pop the output fuses on the things (and I have done it...), you get just a little sound...

DickW?

> Eh, when you open a fuse the circuit is no
> longer complete. I would like to see how a
> speaker can still have a "tiny
> amount" of output with an open speaker
> fuse.

mikebw
09-17-2006, 01:46 AM
perhaps the preamp signal is just enough to get something out of the drivers? Even though the amplifier might not be adding anything to the equation, it might not be totally stopping anything else from passing...

> I dunno why... But if you pop the output
> fuses on the things (and I have done it...),
> you get just a little sound...

> DickW?

dickwest
09-17-2006, 01:15 PM
> Eh, when you open a fuse the circuit is no
> longer complete. I would like to see how a
> speaker can still have a "tiny
> amount" of output with an open speaker
> fuse.

The fuse under discussion re: the Hafler DH-500 is the speaker output fuse on the back panel. This fuse protects the speakers from too much current and should be kept at the 5 amp (or lower) value. But loudness freaks (you know who you are) sometimes blow these fuses.

These fuse blocks are bypassed with a small value film cap and when the fuse is blown a small amount of sound will still get through via the small film cap. This is all explained in the manual -- for those of you who read manuals.

Dick

envisionelec
09-17-2006, 03:59 PM
> The fuse under discussion re: the Hafler
> DH-500 is the speaker output fuse on the
> back panel. This fuse protects the speakers
> from too much current and should be kept at
> the 5 amp (or lower) value. But loudness
> freaks (you know who you are) sometimes blow
> these fuses.

> These fuse blocks are bypassed with a small
> value film cap and when the fuse is blown a
> small amount of sound will still get through
> via the small film cap. This is all
> explained in the manual -- for those of you
> who read manuals.

> Dick

Hmm, interesting. Didn't know that. Then again, I haven't owned a Hafler DH-500.

sswanson17
09-21-2006, 05:59 PM
I have been having the same issue with my Onkyo TX-DS575. I heard of the reset function of pressing the speaker A and Video 1 Button at the same time. I did this, and was able to get the sound back for a little while, but then when I started assigning the Video and digital inputs, the same symptoms re-occured. I have heard that this is a known issue with the Onkyo receiver, but have not tracked down a good solution. I think it may be one of the IC boards for the surround sound.

I have an Onkyo receiver that I have wanted
> to get fixed for a couple of years. Now I
> have a Hafler P500 amp that has the same
> problem on one channel sometimes. The Onkyo
> doesn’t work at all but it was on for
> several days before I noticed the problem so
> I’m not sure how the problem progressed.

> They both have only a VERY slight amount of
> output. It’s almost as if the tape 2 loop on
> a receiver is on but not hooked up. This
> small amount of output at least lets me know
> that nothing is shorted out on the external
> connections.

> Is this type of problem indicative of
> anything in particular?

> The first person to tell me how to fix this
> cheaply myself gets a 6 pack of their
> choice. I wish it were that easy…

> Thanks again,
> Aaron