# Using receiver with external amp



## azaze1 (Nov 29, 2011)

Cutting right to the chase... do you have to do anything specific to disable the internal AMP within a receiver when you use pre-outs to an external AMP?

I've got an Onkyo TX-NR5008 and an Emotiva XPA-3 driving my L,C,R speakers. I've had it all for a while actually, but recently my Onkyo had an issue that lead to a service visit to replace the HDMI board. After getting it back today I began setting up all of my gear once more (Audyssey, inputs etc), and after only about 20 min of mostly idle activity (just setting up stuff, not blasting music or anything) I noticed the receiver is quite hot.

I'm thinking it may have overheated after 2 years of use leading to the HDMI board failure. So.. is there anything that must be done to disable the internal AMP when you have pre-outs to an external AMP? If so, I'm guessing I've not found out how and I'm unnecessarily amplifying my Left/Center/Right channels within the receiver even though they're connected to the Emotiva.


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## htaddikt (May 14, 2007)

If not using the internal amps, you should not have to disable anything. While the 'idling' amp will continue to draw a little power, since you are not driving them, there should not be any issue with heat, etc. unless there is a problem.

I know some earlier Onkyo had some issues running warmer than some more recent models, but if it continues to run hot it should be addressed. 

I've used an external amp to drive the front 3 channels of my Onkyo receiver (809) and let the receiver run the surrounds. It did not run very warm at all. 

I am now running all Emotiva, processor and amps. And likely not going back to a receiver again.


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## Jungle Jack (Jul 28, 2009)

Hello,
I have been using a 3008 since July 2011 and was using a 3007 for about a year before that. I use outboard amplification for channels and the AVR still gets pretty warm. Especially at the back right corner where the HDMI Board is. 

Unfortunately, you cannot turn off the internal amplification. The Denon AVR-4311 and 4520 are the only ones that spring to mind that offer a Preamp Only Mode.
Cheers,
JJ


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## ALMFamily (Oct 19, 2011)

I would suggest just getting a fan and pulling air out of it - there are some pretty good ones that are about 1" thick that hjones linked a while back. If interested, I saved the link and can post it.


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## azaze1 (Nov 29, 2011)

ALMFamily said:


> I would suggest just getting a fan and pulling air out of it - there are some pretty good ones that are about 1" thick that hjones linked a while back. If interested, I saved the link and can post it.


Sounds like a good idea, if you wouldn't mind posting the link... I'd appreciate it. Otherwise I'm thinking of some Noctua computer case fans (140mm) they're utterly silent, just gotta figure out how to power them after setting them atop the receiver.


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## ALMFamily (Oct 19, 2011)

Sorry - worked in the HT most of the day. Here it is:

http://www.buyextras.com/cocofanki14q.html


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## jevans64 (Dec 24, 2012)

This company makes some neat stuff that would integrate well with A/V components but they are on the expensive side. The unit in the link is $275 on Amazon. LOL

http://www.coolcomponents.com/Component-Cooling-System-_p_191.html


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## jevans64 (Dec 24, 2012)

azaze1 said:


> Sounds like a good idea, if you wouldn't mind posting the link... I'd appreciate it. Otherwise I'm thinking of some Noctua computer case fans (140mm) they're utterly silent, just gotta figure out how to power them after setting them atop the receiver.


I've tested a lot of PC cooling fans and Noctua and Yate Loon are some of the quietest for the amount of CFM they produce. The BuyExtra link has some Yate Loon fans available and I assume the fans can be replaced with any brand. Delta and Panaflo are some of the loudest but you can't beat the CFM these put out.


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## climber07 (Apr 26, 2012)

They do run a little hot. That is the nature of all class A/B amps, even when they aren't putting out a lot of power. Plus the added size of the transformers and video circuitry. 

You can look at these:
Coolerguys Cabcool 

These fans are all programmable with the LED readout and keep the closed cabinet cool. They even shut off and start at your specified temps... Here's what it looks like installed:


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## Todd Anderson (Jul 24, 2009)

+1 for the cooler guys. I have a dual fan made by them that has a temperature trigger. Has worked great for years...


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## 8086 (Aug 4, 2009)

azaze1 said:


> Cutting right to the chase... do you have to do anything specific to disable the internal AMP within a receiver when you use pre-outs to an external AMP?
> 
> I've got an Onkyo TX-NR5008 and an Emotiva XPA-3 driving my L,C,R speakers. I've had it all for a while actually, but recently my Onkyo had an issue that lead to a service visit to replace the HDMI board. After getting it back today I began setting up all of my gear once more (Audyssey, inputs etc), and after only about 20 min of mostly idle activity (just setting up stuff, not blasting music or anything) I noticed the receiver is quite hot.
> 
> I'm thinking it may have overheated after 2 years of use leading to the HDMI board failure. So.. is there anything that must be done to disable the internal AMP when you have pre-outs to an external AMP? If so, I'm guessing I've not found out how and I'm unnecessarily amplifying my Left/Center/Right channels within the receiver even though they're connected to the Emotiva.


If there isn't a load or speakers attached to the amplifier, then in my reasoning it should not generate much heat. 

Get yourself a Lasko blower, position it above the Onkyo and aim the laser like stream of air 45° down at the receiver. See if this fixes your problem. If not, there's about a million other uses for the Lasko; like keeping cool in the summer or drying a floor.


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## Odougbo (Oct 16, 2011)

COOL! 

Can you send a link to the thermostat plz?


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## azaze1 (Nov 29, 2011)

It's not quite the coolerguys thing.... but my TV stand is the Standout Designs Haven 82" which has an integrated dual fan at the top of both the left and right cabinets already. It's utterly silent, and turns on when it detects a certain level of heat which... in my case means it's always on when my Onkyo is on.

I'm sure the temps would be worse without it, but I can say for sure it's not nearly enough to keep the Onkyo cool. I need something sucking the air out of the top of the receiver.

I've purchased an AC/Molex power brick adapter for $11, and a 140mm Noctua computer case fan which I plan on setting right on top of the Onkyo in the rear right. It all arrives tomorrow so I'll have some feedback soon. Total cost was about $33.

Thanks for all the feedback and ideas. HTS continues to be a purely helpful forum


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## 8086 (Aug 4, 2009)

azaze1 said:


> It's not quite the coolerguys thing.... but my TV stand is the Standout Designs Haven 82" which has an integrated dual fan at the top of both the left and right cabinets already. It's utterly silent, and turns on when it detects a certain level of heat which... in my case means it's always on when my Onkyo is on.
> 
> I'm sure the temps would be worse without it, but I can say for sure it's not nearly enough to keep the Onkyo cool. I need something sucking the air out of the top of the receiver.
> 
> ...


I'm running a noctua case fan in my computer now. In fact, all my fans are noctua. They are great. But it's not going to move enough air to cool a hot amp. It was a waste of cash if you ask me, so before they arrive; try a normal room fan blowing on the top of the chassis; if that does not fix your problem, then return or refuse delivery of the package.


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## azaze1 (Nov 29, 2011)

Silence or close to it is very important to me. Any obvious fan noise will negate much of the work I've put into my home theater experience. My HTPC is completely solid state with just 1 tiny add-in 40mm fan to move some air around in the H5S hd-plex case so that my radeon 6450 doesn't overheat.

With the cabinet door closed I do not hear a sound, but with a regular room fan blowing in the back of the onkyo I don't think I could avoid hearing the noise.

Finding the right combination of gear is a real pain when you've got all your gear in the audible range of the viewer. I so wish I had a room where I could put all of this stuff into an AV cabinet/closet and not worry about silent parts.... oh how that would make life easier


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## azaze1 (Nov 29, 2011)

Well, it's only 1 night, but after about 30 min of use I can say this Noctua fan is keeping the receiver pretty cool. It's night and day difference than when I was simply configuring stuff in the setup menu after 15 min of mostly idle activity.

So takeway is... this bizzare setup is working, but now I realize that this AC -> Molex power brick adapter will leave the Fan running 24/7 (there is no AC plug in the back of my Onkyo). So... now I"m wondering if I can find a 1/8 inch Mono plug to Molex adapter.... and plug it into my 12v Trigger for Zone 3. I"m using Zone 2 to fireup my Emotiva already, so I can add the Zone 3 to my list of macro activities when turing on my gear if I can just find a cable that will change a 1/8th Mono jack into a Molex male 

I've searched a bit already, no dice.


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## 8086 (Aug 4, 2009)

azaze1 said:


> Well, it's only 1 night, but after about 30 min of use I can say this Noctua fan is keeping the receiver pretty cool. It's night and day difference than when I was simply configuring stuff in the setup menu after 15 min of mostly idle activity.
> 
> So takeway is... this bizzare setup is working, but now I realize that this AC -> Molex power brick adapter will leave the Fan running 24/7 (there is no AC plug in the back of my Onkyo). So... now I"m wondering if I can find a 1/8 inch Mono plug to Molex adapter.... and plug it into my 12v Trigger for Zone 3. I"m using Zone 2 to fireup my Emotiva already, so I can add the Zone 3 to my list of macro activities when turing on my gear if I can just find a cable that will change a 1/8th Mono jack into a Molex male
> 
> I've searched a bit already, no dice.


A craftsman auto switch will cure your blues. It will sense when power is drawn through one outlet and turn on the 2nd outlet automatically.

http://www.sears.com/craftsman-auto-switch/p-00924031000P


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## azaze1 (Nov 29, 2011)

That's a very cool little gaget, but I'm afraid it wont work for me. 

I've got two dedicated 20amp circuits just for my home theater, and I'd have hang this power switch off of one of my 20amp power strips and then plug my receiver into this 15amp device which would choke the amperage available to the receiver. 

Right now I've got super clean power, with no power conditioners governing (limiting) bursts allowing my receiver and amp to take as many deeeeeep breathes (draw power in bursts) as they like which happens a lot during action scenes.


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## 8086 (Aug 4, 2009)

azaze1 said:


> That's a very cool little gaget, but I'm afraid it wont work for me.
> 
> I've got two dedicated 20amp circuits just for my home theater, and I'd have hang this power switch off of one of my 20amp power strips and then plug my receiver into this 15amp device which would choke the amperage available to the receiver.
> 
> Right now I've got super clean power, with no power conditioners governing (limiting) bursts allowing my receiver and amp to take as many deeeeeep breathes (draw power in bursts) as they like which happens a lot during action scenes.


If the auto-switch is a socket blocker, then use a short extension cable, like the one i got at Home Depot. When a wall wart blocks an outlet I often resort to a similar 12 to 24" cable or powerstrip.


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## AudiocRaver (Jun 6, 2012)

azaze1 said:


> That's a very cool little gaget, but I'm afraid it wont work for me.
> 
> I've got two dedicated 20amp circuits just for my home theater, and I'd have hang this power switch off of one of my 20amp power strips and then plug my receiver into this 15amp device which would choke the amperage available to the receiver.
> 
> Right now I've got super clean power, with no power conditioners governing (limiting) bursts allowing my receiver and amp to take as many deeeeeep breathes (draw power in bursts) as they like which happens a lot during action scenes.


You might be surprised how little power your system is using. I run 2 six-core PCs with added video cards, four monitors, three large stereo power amps, two subs, a bunch of other audio gear, have a Kill-O-Watt meter monitoring at all - it usually sits at 3.5 A, occasionally peeks above 4 A. The meter costs $30, might be interesting to know what you are really drawing. Just a thought.:T


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