Overheating of Onkyo TX-SR 606

[FrankMeng]

I bought a receiver of Onkyo TX-SR 606.
Everthing works fine, except the receiver becomes very hot if the
power is on.
Even there is no signal to the receiver, as long as the power is on, I
can't put my hand on it for more than half a second because the box
burns my hand.
Is this normal for Onkyo TX-SR 606?
Will the overheating cause a problem after a while (several months, or
years)?

[Dave]

"FrankMeng" > wrote in message
...
>I bought a receiver of Onkyo TX-SR 606.
> Everthing works fine, except the receiver becomes very hot if the
> power is on.
> Even there is no signal to the receiver, as long as the power is on, I
> can't put my hand on it for more than half a second because the box
> burns my hand.
> Is this normal for Onkyo TX-SR 606?
> Will the overheating cause a problem after a while (several months, or
> years)?

Hot enough to burn you is too hot. The thing that kills electronics is
heat. Most components are rated for use for a specified number of hours
(mean-time between failure or MTBF) at 85C... there are some rated at 105C
but consumer-grade equipment manufacturers are generally too cheap to use
them.

I have no knowledge of this particular amp, but I'd guess the bias of at
least one channel is way off if the amp runs that hot at idle (no signal).
Biasing of the output transistors sets the idle current... on some amps it's
adjustable with a trimpot on the amp PCB (one per channel) and on some amps
it's fixed and can only be changed by swapping out a resistor with one of a
different value.

Dave

[Art]

I have one of their higher end models (TX-SR 8??) and it gets hot but not
too hot to touch and hold, even when run for hours.



"FrankMeng" > wrote in message
...
>I bought a receiver of Onkyo TX-SR 606.
> Everthing works fine, except the receiver becomes very hot if the
> power is on.
> Even there is no signal to the receiver, as long as the power is on, I
> can't put my hand on it for more than half a second because the box
> burns my hand.
> Is this normal for Onkyo TX-SR 606?
> Will the overheating cause a problem after a while (several months, or
> years)?

[Mark D. Zacharias[_3_]]

"Art" > wrote in message
m...
>I have one of their higher end models (TX-SR 8??) and it gets hot but not
>too hot to touch and hold, even when run for hours.
>
>
>
> "FrankMeng" > wrote in message
> ...
>>I bought a receiver of Onkyo TX-SR 606.
>> Everthing works fine, except the receiver becomes very hot if the
>> power is on.
>> Even there is no signal to the receiver, as long as the power is on, I
>> can't put my hand on it for more than half a second because the box
>> burns my hand.
>> Is this normal for Onkyo TX-SR 606?
>> Will the overheating cause a problem after a while (several months, or
>> years)?
>
>

If it gets that hot with no other symptoms it's possible that the bias is
not adjusted properly. This needs to be done by a technician, ideally by an
authorized Onkyo servicer, especially if it's under factory warranty. If
under warranty, checking / adjusting in this situation should be at no
charge.

Mark Z.

[rppb]

I have the 806 and on the Onkyo web site they say some of their receivers
run hot. I would contact their customer support. I bought a small fan for my
806 and that keeps it cool. I have never run it without the fan but I read
one review from a Crutchfield customer that stated that his 806 ran very
hot.
"FrankMeng" > wrote in message
...
>I bought a receiver of Onkyo TX-SR 606.
> Everthing works fine, except the receiver becomes very hot if the
> power is on.
> Even there is no signal to the receiver, as long as the power is on, I
> can't put my hand on it for more than half a second because the box
> burns my hand.
> Is this normal for Onkyo TX-SR 606?
> Will the overheating cause a problem after a while (several months, or
> years)?

[JVC Dude]

I recently installed a TXSR706 and over 2 hrs that got quite hot even though
not being driven for most of that time..
Whilst this may be a design issue on the family of models, it will
eventually lead to problems in a few years, drying up many capacitors with
the heat soak. Maybe put extra feet underneath, and consider the fan idea
for some forced cooling.

[[email protected]]

On Oct 15, 7:49*am, "JVC Dude" > wrote:
> I recently installed a TXSR706 and over 2 hrs that got quite hot even though
> not being driven for most of that time..
> Whilst this may be a design issue on the family of models, it will
> eventually lead to problems in a few years, drying up many capacitors with
> the heat soak. *Maybe put extra feet underneath, and consider the fan idea
> for some forced cooling.

I'm thinking that a good class ab is going to bias for some double
digit percentage of it's rated power. That can be a lot of watts at
idle for some of them. Plus the higher idle biasing also means it is
operating in class a mode for longer as well, right?

[[email protected]]

I don't think this is normal,maybe you can change another one if you
haven't bought for a long time, i know a web site which sell consumer
electronics,it's http://www.gizmograbber.com, you can come to find the
relative product, maybe it can help you solve the problem.

[j.carter]

I've got two Onkyo receivers that always seemed to run hot. Both went
bellyup shortly after the waranties ran out (power supply problems).
No more Onkyos for me!!!



> wrote in message
...
>I don't think this is normal,maybe you can change another one if you
> haven't bought for a long time, i know a web site which sell consumer
> electronics,it's http://www.gizmograbber.com, you can come to find the
> relative product, maybe it can help you solve the problem.

[rdclark]

On Oct 14, 10:20*am, FrankMeng > wrote:
> I bought a receiver of Onkyo TX-SR 606.
> Everthing works fine, except the receiver becomes very hot if the
> power is on.
> Even there is no signal to the receiver, as long as the power is on, I
> can't put my hand on it for more than half a second because the box
> burns my hand.
> Is this normal for Onkyo TX-SR 606?
> Will the overheating cause a problem after a while (several months, or
> years)?

Modern digital receivers require a lot of ventilation. They should not
be enclosed, there should be flow-through ventilation, and there
should be several inches of clear air above them.

That said, Onkyo's recent receivers have a reputation for running
hotter than other brands, and many owners are adding forced-air
ventilation to their installations. There is a way to display an
internal temperature readout on Onkyos, which may help determine if
yours is unusually hot. See the FAQ here:

http://www.avsforum.com/avs-vb/showthread.php?t=935808

This is for the TX-SR705, but the procedure is the same:

How do I see the Temperature readout on this receiver?
1) Turn on Receiver
2) HOLD down the "Display" button and press "Standby" button once.
3) Release the "Display" button.
4) Now press the "Tone" button once
5) The temperature in Celsius and Fahrenheit will be displayed. These
temperatures are being displayed in real time so you can leave this
info on display for as long as you want to monitor the receivers temp.

[Mike S[_2_]]

Set the receiver output to 4ohms for the speakers, this keeps the receiver a
little cooler.


"rdclark" > wrote in message
...
On Oct 14, 10:20 am, FrankMeng > wrote:
> I bought a receiver of Onkyo TX-SR 606.
> Everthing works fine, except the receiver becomes very hot if the
> power is on.
> Even there is no signal to the receiver, as long as the power is on, I
> can't put my hand on it for more than half a second because the box
> burns my hand.
> Is this normal for Onkyo TX-SR 606?
> Will the overheating cause a problem after a while (several months, or
> years)?

Modern digital receivers require a lot of ventilation. They should not
be enclosed, there should be flow-through ventilation, and there
should be several inches of clear air above them.

That said, Onkyo's recent receivers have a reputation for running
hotter than other brands, and many owners are adding forced-air
ventilation to their installations. There is a way to display an
internal temperature readout on Onkyos, which may help determine if
yours is unusually hot. See the FAQ here:

http://www.avsforum.com/avs-vb/showthread.php?t=935808

This is for the TX-SR705, but the procedure is the same:

How do I see the Temperature readout on this receiver?
1) Turn on Receiver
2) HOLD down the "Display" button and press "Standby" button once.
3) Release the "Display" button.
4) Now press the "Tone" button once
5) The temperature in Celsius and Fahrenheit will be displayed. These
temperatures are being displayed in real time so you can leave this
info on display for as long as you want to monitor the receivers temp.

[rdclark]

On Oct 20, 7:08*am, "Mike S" > wrote:
> Set the receiver output to 4ohms for the speakers, this keeps the receiver a
> little cooler.

Even if the TX-SR606 were rated for 4-ohm loads (which it isn't) or
had such a switch setting (which it doesn't), this would still be the
dumbest thing I ever heard.

If the receiver did have a 4-ohm setting and you used it with 8 ohm
speakers, all you would do is reduce the dynamic range of the
amplifiers by limiting the available current. This would make no
difference (either in heat or sound) at normal listening levels, but
it would compromise the sound quality needlessly when the system was
operating near its limits.

[David[_3_]]

"rdclark" > wrote in message
...
On Oct 20, 7:08 am, "Mike S" > wrote:
> Set the receiver output to 4ohms for the speakers, this
> keeps the receiver a
> little cooler.

Even if the TX-SR606 were rated for 4-ohm loads (which it
isn't) or
had such a switch setting (which it doesn't), this would
still be the
dumbest thing I ever heard.

If the receiver did have a 4-ohm setting and you used it
with 8 ohm
speakers, all you would do is reduce the dynamic range of
the
amplifiers by limiting the available current. This would
make no
difference (either in heat or sound) at normal listening
levels, but
it would compromise the sound quality needlessly when the
system was
operating near its limits.

Actually, if a receiver has a 8/4 - ohm switch, when in the
4 - ohm position the rail voltage is dropped on the output
stage devices. The does actually result in less heat at no
load (for a constant bias current) and also for low level
listening.

David

[Arny Krueger]

"rdclark" > wrote in message

> On Oct 20, 7:08 am, "Mike S" > wrote:
>> Set the receiver output to 4ohms for the speakers, this
>> keeps the receiver a little cooler.
>
> Even if the TX-SR606 were rated for 4-ohm loads (which it
> isn't) or had such a switch setting (which it doesn't),
> this would still be the dumbest thing I ever heard.

> If the receiver did have a 4-ohm setting and you used it
> with 8 ohm speakers, all you would do is reduce the
> dynamic range of the amplifiers by limiting the available
> current.

That's not what the switch does. What it does is reduce the supply rails to
the output stage.

That naturally reduces heat dissipation under both quiescent and active
operation. IOW it will run a little cooler, whether you are playing music or
not.

> This would make no difference (either in heat or
> sound) at normal listening levels, but it would
> compromise the sound quality needlessly when the system
> was operating near its limits.

Yes, this will reduce the maximum voltage that is available, but most modern
home audio power amplifiers are rarely if ever used anywhere their maximum
ratings.

[Mike S[_2_]]

Thank you guys for the support. My TX-SR 805 does have this option, not a
switch,
but you do it in the setup screen in the receiver.



"Arny Krueger" > wrote in message
. ..
> "rdclark" > wrote in message
>
>> On Oct 20, 7:08 am, "Mike S" > wrote:
>>> Set the receiver output to 4ohms for the speakers, this
>>> keeps the receiver a little cooler.
>>
>> Even if the TX-SR606 were rated for 4-ohm loads (which it
>> isn't) or had such a switch setting (which it doesn't),
>> this would still be the dumbest thing I ever heard.
>
>> If the receiver did have a 4-ohm setting and you used it
>> with 8 ohm speakers, all you would do is reduce the
>> dynamic range of the amplifiers by limiting the available
>> current.
>
> That's not what the switch does. What it does is reduce the supply rails
> to the output stage.
>
> That naturally reduces heat dissipation under both quiescent and active
> operation. IOW it will run a little cooler, whether you are playing music
> or not.
>
>> This would make no difference (either in heat or
>> sound) at normal listening levels, but it would
>> compromise the sound quality needlessly when the system
>> was operating near its limits.
>
> Yes, this will reduce the maximum voltage that is available, but most
> modern home audio power amplifiers are rarely if ever used anywhere their
> maximum ratings.
>
>
>