Home audio amplifier failure

[Gary]

First, this is my first entry into this group. I ran a NG search for this
problem, and the result(s) indicated
here. Sorry, if that was wrong.

I have an Onkyo home audio component system. The
amplifier in this system(Onkyo A-RV401) has flamed
out, as least I'm pretty sure it's the amplifier.

Next, I'm not an electronics guy. I'm just looking for a
little seasoned advice.

The system no longer produces any sound, no tuner,
tape, CD, headphones, nothing. However, I can crank
up the volume to full, and faintly hear the audio. As
usual, this worked fine one day, and failed the next.

It appears that this component can be replaced with
something like, for around $400-600. It also appears
that current models have the tuner/amplifier integrated
into a single unit, where the existing unit(s) are separate.

It's my opinion(only opinion) that replacement should
be the choice, rather than a repair attempt.

Comments?

Thanks, for the help.

Gary

 

[CJT]

First, this is my first entry into this group. I ran a NG search for this
problem, and the result(s) indicated
here. Sorry, if that was wrong.

I have an Onkyo home audio component system. The
amplifier in this system(Onkyo A-RV401) has flamed
out, as least I'm pretty sure it's the amplifier.

Next, I'm not an electronics guy. I'm just looking for a
little seasoned advice.

The system no longer produces any sound, no tuner,
tape, CD, headphones, nothing. However, I can crank
up the volume to full, and faintly hear the audio. As
usual, this worked fine one day, and failed the next.

It appears that this component can be replaced with
something like, for around $400-600. It also appears
that current models have the tuner/amplifier integrated
into a single unit, where the existing unit(s) are separate.

It's my opinion(only opinion) that replacement should
be the choice, rather than a repair attempt.

Comments?

Thanks, for the help.

Gary

Used amps in good condition can often be found at a small fraction of
the price of new.

Remember - you were happy with your (used -- by you) amp until it broke,
so why not consider a good used (by somebody else) amp? There are lots
of people who regularly "trade up" whether they can hear the difference
or not -- it's a form of self-flattery. That puts some pretty good
equipment on the market cheap.

 

[TimPerry]

First, this is my first entry into this group. I ran a NG search for this
problem, and the result(s) indicated
here. Sorry, if that was wrong.

I have an Onkyo home audio component system. The
amplifier in this system(Onkyo A-RV401) has flamed
out, as least I'm pretty sure it's the amplifier.

Next, I'm not an electronics guy. I'm just looking for a
little seasoned advice.

The system no longer produces any sound, no tuner,
tape, CD, headphones, nothing. However, I can crank
up the volume to full, and faintly hear the audio. As
usual, this worked fine one day, and failed the next.

It appears that this component can be replaced with
something like, for around $400-600. It also appears
that current models have the tuner/amplifier integrated
into a single unit, where the existing unit(s) are separate.

It's my opinion(only opinion) that replacement should
be the choice, rather than a repair attempt.

Comments?

Thanks, for the help.

Gary

find a repair shop and have it fixed... should cost $75 to $100 for repair

 

[NSM]

It appears that this component can be replaced with
something like, for around $400-600. It also appears
that current models have the tuner/amplifier integrated
into a single unit, where the existing unit(s) are separate.

It's my opinion(only opinion) that replacement should
be the choice, rather than a repair attempt.

Perfectly serviceable but it's your choice. I even see them in thrifts, the
only problem being testing them there.

N

 

[Gary Walker]

Used amps in good condition can often be found at a small fraction of
the price of new.

Remember - you were happy with your (used -- by you) amp until it broke,
so why not consider a good used (by somebody else) amp? There are lots
of people who regularly "trade up" whether they can hear the difference
or not -- it's a form of self-flattery. That puts some pretty good
equipment on the market cheap.

Yes, you are quite right. And, I often criticize those for
making a brand switch under the light of comparison
of a bright shiny new model vs. retention of the current
brand.

Although I wasn't really looking specifically to change
brands, I was looking at everything available. Things
like this change/evolve so quickly, it's easy for me to
get behind.

Regarding the used/trade-in issue, I hadn't really given
that any thought. It is a good suggestion. But, for some-
one like me, with minimal ability to detect potential
problems in electronic equipment, I'd prefer new.

Also, unless possibly a high end audio outlet, I've have
no idea where to find used equipment as this. I guess
the pawnshop is certainly an option, but I'd think one
would need considerable more savvy than me.

Thanks,

Gary

 

[Gary Walker]

Perfectly serviceable but it's your choice. I even see them in thrifts, the
only problem being testing them there.

N

That's my take on the whole thing. But, I will take this,
and the other suggestions into consideration. Problem
is, I don't know an RF from a DSP, and unless I find
someone I can trust, my scrutiny is suspect.

Thanks,

Gary

 

[Gary Walker]

find a repair shop and have it fixed... should cost $75 to $100 for repair

I will check into it. I do have a friend who repairs guitar
amplifiers. Not that I would try to cop a free repair, just
that I would trust him. But, I thought that one could
easily exceed the unit value by attempting repair.

Thanks,

Gary

 

[Mark D. Zacharias]

However, I can crank

up the volume to full, and faintly hear the audio>


Sounds like maybe the tape monitor is engaged. Maybe nothing wrong worth the
amp. Even if the amp does have a problem, the A-RV401 is a nice model, worth
repair.

Mark Z.

 

[Gary Walker]

up the volume to full, and faintly hear the audio>


Sounds like maybe the tape monitor is engaged. Maybe nothing wrong worth the
amp. Even if the amp does have a problem, the A-RV401 is a nice model, worth
repair.

Mark Z.

I understand your comment, but although I have engaged
all the input sources at one time or another, the faint audio
can be detected as from the source intended.

Yes. it has been a great unit. It was suggested earlier that
repair might be worth looking into, which I will. I'd hate
to just throw the whole thing away due to something small.

Thanks,

Gary

 

[Mark D. Zacharias]

I understand your comment, but although I have engaged
all the input sources at one time or another, the faint audio
can be detected as from the source intended.

Yes. it has been a great unit. It was suggested earlier that
repair might be worth looking into, which I will. I'd hate
to just throw the whole thing away due to something small.

Thanks,

Gary

Then perhaps a failure of the regulated power supply area. You'd hear
nothing at all if the main amp was blown or if there were a large DC offset.
Could be one or more open resistors feeding voltage regulator(s) in the
power supply. Fairly common problem on similar model Onkyo receivers, though
I've only worked on one or two amps like yours, and it's been a while.

Mark Z.

Mark Z.

 

[Gary Walker]

Then perhaps a failure of the regulated power supply area. You'd hear
nothing at all if the main amp was blown or if there were a large DC offset.
Could be one or more open resistors feeding voltage regulator(s) in the
power supply. Fairly common problem on similar model Onkyo receivers, though
I've only worked on one or two amps like yours, and it's been a while.

Mark Z.

Mark Z.

Well, as I said, I don't really know. I can say that this amp
never runs about 30% volume, I just use it mostly for
headphone listening. If I juice up the volume to 100%, I'll
hear the audio at about the depth I might expect at 1-5%.

"The amplifier's just ain't amplifying". <g>

I still haven't decided, intending on contact of an amp
repair friend. But, I have found another equivalent
replacement Onkyo for ~$300 at Fry's. It's a TX-8511.

Thanks,

Gary

 

[Ron(UK)]

up the volume to full, and faintly hear the audio>


Sounds like maybe the tape monitor is engaged. Maybe nothing wrong worth the
amp. Even if the amp does have a problem, the A-RV401 is a nice model, worth
repair.

Mark Z.

Just a thought, but it hasn`t got those linking plugs or jumpers
between the preamp and power amps has it? have they been removed, or has
some other piece of kit been disconnected?

Ron

 

[Gary Walker]

Just a thought, but it hasn`t got those linking plugs or jumpers
between the preamp and power amps has it? have they been removed, or has
some other piece of kit been disconnected?

Ron



--
Lune Valley Audio
Public address system
Hire, Sales, Repairs
www.lunevalleyaudio.com

Unfortunately, I don't fully understand "linking plugs",
and never really have fully understood "preamp" vs.
"power amp". But, I can say this:

The system(components:tuner, amplifier, headphones)
were in use the previous evening ~22:30-23:30, with-
out sign of failure. This system has been used daily for

10 years.

Proceeding to use the system during the subsequent
day and, no audio.... I guess something could have
wiggled loose, but since I can get this faint audio, and
I have done a cursory "reset" of all rear panel attach-
ments, I just assume it's gone.

Although this system is only used for 1-2 hour periods
at a time, it will sometimes remain on for 24 hour periods.

Although not electronically oriented myself, I have to
assume these things have a MTBF. I guess after >10
years of flawless service, my number's up. Additionally,
the components are positioned in a very dusty area, and
haven't been cleaned since new. Actually, it's no more
dusty that any other room, but due to lack of cleaning,
it appears very dusty.

IOW. The whole thing is located in a music room, with
other instruments and junk(need I say more?).

Thanks,

Gary

 

[Jim Adney]

I have an Onkyo home audio component system. The
amplifier in this system(Onkyo A-RV401) has flamed
out, as least I'm pretty sure it's the amplifier.

The system no longer produces any sound, no tuner,
tape, CD, headphones, nothing. However, I can crank
up the volume to full, and faintly hear the audio. As
usual, this worked fine one day, and failed the next.

It appears that this component can be replaced with
something like, for around $400-600. It also appears
that current models have the tuner/amplifier integrated
into a single unit, where the existing unit(s) are separate.

Separate units like yours are generally easier to fix than integrated
units, so this helps. I don't know anything about your model, but my
first inclination would be to see if it can be fixed. These items
generally are fixable and for much less money than the replacement
cost you mention.

The fact that both channels both seem to have died at the same time
makes this seem like it might be a simple problem. It might pay to get
your friend over there just to check out the system and the switch
settings (like the tape monitor that Mark mentioned.)

I agree completely with your other posts that it would all depend on
finding someone you think you can trust to take a look at it.

-

 

[Gary Walker]

Separate units like yours are generally easier to fix than integrated
units, so this helps. I don't know anything about your model, but my
first inclination would be to see if it can be fixed. These items
generally are fixable and for much less money than the replacement
cost you mention.

The fact that both channels both seem to have died at the same time
makes this seem like it might be a simple problem. It might pay to get
your friend over there just to check out the system and the switch
settings (like the tape monitor that Mark mentioned.)

I agree completely with your other posts that it would all depend on
finding someone you think you can trust to take a look at it.

-

Thanks. I am weaning off the unit for these last few days.

That'll make my diagnosis more thorough.

Gary

 

[CJT]

Separate units like yours are generally easier to fix than integrated
units, so this helps. I don't know anything about your model, but my
first inclination would be to see if it can be fixed. These items
generally are fixable and for much less money than the replacement
cost you mention.

The fact that both channels both seem to have died at the same time
makes this seem like it might be a simple problem.

That's a good point. It suggests some problem with a section that's
common to both channels -- like a power supply.

It might pay to get

 

[NSM]

Unfortunately, I don't fully understand "linking plugs",
and never really have fully understood "preamp" vs.
"power amp". But, I can say this:

On the back there may be some connectors labelled Out and In which need to
be connected together to make the system work. Can you post a picture of the
back somewhere (not in this group please)?

N

 

[Gary Walker]

On the back there may be some connectors labelled Out and In which need to
be connected together to make the system work. Can you post a picture of the
back somewhere (not in this group please)?

N

Well yeah, I'm aware of the component plugs on the rear.
I'd just never heard them referred to as linking plugs.

Come to think of it, I'd never really known their true
description other than RCAplug/Miniplug etc.

With regard to a picture of the rear, no I don't have one,
and I have no scanner with which to record the diagram
in the hardcopy I do have.

However, I've managed to locate:
http://onkyousa.com/own_manuals.cfm?cat=Receiver
which shows the A-RV401 instruction manual. Although
it doesn't seem an exact copy of the hardcopy I have, it
does have some documentation. But, unlike my hardcopy,
I didn't see a simple back panel schematic as is shown in
my hardcopy. Perhaps, I just overlooked it.

The diagnostic section occurs on pp.15.

But....

I did overlook/fail to think about/stupidly ignore the diag-
nostic section(aka troubleshooting) in either copy. Using
the hardcopy manual, and following the procedures for
"power but no sound", I see:

Tape monitor on - No, but I do now recall having prob-
lems with this in the past when I'd press the wrong butt-
on in the dark. Pressing tape2 switches to tape2 input,
but merely pressing tuner will not return to tuner, but
shows T2 monitor. Another press of tape2 releases the
T2 monitor, and returns the faint signal.

Bad connections - Possible, but since I've reset all conn-
ections, and I can get the faint audio from all sources(
tuner, CD) available, this possibility seems very unlikely.

Amplifier protection circuitry has been activated - I have
no clue. The response here is to contact the service cen-
ter.

In the online troubleshooting guide, a muting button is
described. My unit has no mute button, or I just can't
seem to find it. It does have a standby button, and that
will disable sound, but it is correctly positioned. Perhaps
this standby is synonymous with muting?

Although the online manual indicates that "protect" will
be shown if the protective circuitry activation has occ-
urred, my hardcopy manual make no mention of this. I
assume I have no protect designation.

I did just returned from a closer unit inspection. In the amp view window,
where the input source is shown, I do see a "very" small muting word. Review
of the online manual pp. 11 describes muting as activated via the remote
unit. Well, although I have had the remote connected(I guess it's a remote
receiver, because the remote is wireless), not only have I never used the
remote, I'm not really sure even where it is. The text suggests that the
only way to de-mute is via the remote, or a cycle of the amp's power. I can
certainly say that a power cycle on the amp has no effect on this.

Further research on this seems to indicate that the muting
function is stuck on. Even after disconnecting the rc cable
from the amp(one rc cable connects the tuner to the amp,
and the other rc cable connects the tape to the CD), the
amp continues to initialize in mute mode. It appears that
this is probably the problem, but I'll be damned if I know
how to correct it. Perhaps, I'll either have it looked at,
or contact Onkyo for assistance(unlikely they'll bother
with equipment this old).

Sorry, for the verbosity....

Thanks,

Gary

 

[NSM]

Further research on this seems to indicate that the muting
function is stuck on. Even after disconnecting the rc cable
from the amp(one rc cable connects the tuner to the amp,
and the other rc cable connects the tape to the CD), the
amp continues to initialize in mute mode. It appears that
this is probably the problem, but I'll be damned if I know
how to correct it. Perhaps, I'll either have it looked at,
or contact Onkyo for assistance(unlikely they'll bother
with equipment this old).

That'll do it. Until you can un mute it you will have no sound.

As for the linking or jumping plugs, this model probably doesn't have them
but if you look at the bottom right diagram on page 4 of the A-RV401 manual
on a model that _WAS_ designed this way the equalizer jacks would be
permanently connected in to out, left to left and right to right with very
short cables. Removing these without connecting an equalizer would also cut
the sound.

N

 

[Gary Walker]

That'll do it. Until you can un mute it you will have no sound.

As for the linking or jumping plugs, this model probably doesn't have them
but if you look at the bottom right diagram on page 4 of the A-RV401 manual
on a model that _WAS_ designed this way the equalizer jacks would be
permanently connected in to out, left to left and right to right with very
short cables. Removing these without connecting an equalizer would also cut
the sound.

N

Thanks, I did find the remote, and will research possibly
trying to use it to de-mute, but I don't hold much hope.

I've also sent mail to Onkyo explaining the situation, but
don't hold much hope there either.

I'll post my progress as this saga unfolds.

Thank you, and everyone for the assistance and contri-
bution(s).

BTW. That "muting" word is very very tiny, meant for
eyes much younger than mine.

Gary