How to run a second power amp with a receiver?

photo is correct
the 2 males replace the original jumper pin
the female allows for an rca cable from one amp to the other
 
Actually, no. The two males replace the jumper and another interconnect goes from the dangling female to the external amp.
Sit corrected. Since the grounds are shared, that should indeed work even if the outputs are not on the same "leg".
 
there is a check to be made to all of this
speakers powered by different amps can be out of phase with eachother unless all amps are the same model

:thumbsup:

Easiest way to phase speakers with mismatched equipment is to connect the first pair of speakers normally then phase the next pair to the first pair, and so on. It only took me about ten minutes to phase all the speakers and believe you me, you can certainly hear that something is off if only one speaker is not phased correctly with the others. It kills the bass. :mad:
 
Actually, no. The two males replace the jumper and another interconnect goes from the dangling female to the external amp.

These are the one's I use. I have a box of many different Y configurations. You need them if you wanna build big.
 
Unfortunately, receiver manufacturers rarely publish specs for preamplifier outputs. Nor are input load specs published for all power amplifiers either which can vary widely from one amplifier to the next. The effects of improper loading between components is no different than it is for phono cartridges - namely irregular frequency response.

Without knowing what the values are for the specific units, it is impossible to answer in the absolute whether there will be any negative sonic effects or not.
Here is the scoop...

Input impedance of second amp......47000 ohms
Input impedance of Onkyo TX8500 amp.......???
Output impedance of Onkyo TX8500 preamp......???

Should I go for it?

What is the worst that can happen? Could I compromise reliability of the preamp / receiver?
 
Sure. Why not! Not even close!

My thought was that the engineers at Onkyo probably did not intend for this and maybe the impedance specs of the preamp / amp within the TX8500 are such that this will pose a problem. This is the reason for not doing this. On the other hand, maybe the components are spec'd for this and it will work out just dandy.
 
My thought was that the engineers at Onkyo probably did not intend for this and maybe the impedance specs of the preamp / amp within the TX8500 are such that this will pose a problem.

The engineers did intend for this or else they would not have had these options on any of their units.

People have been doing things like this for a long long time using multiple pieces of equipment.

In my house, I have a Pioneer SA-8500II and 9500II plus a Sherwood S-6040-CP along with a Pioneer SX-1010 all using Y adapters because each one has pre out and main in options except the sherwood as it is just a straight power amp. Its meant to mix and match at your hearts content.
 
Seek and ye shall find...

Amp input 50k ohms
Pre out 3k ohms.

3k pre driving ~24k amplifier load. Not ideal, but it's cheap to give it a try!
OK, so what is the relationship exactly between the impedance at the pre and impedance at the amp? I understand by running the amps in parallel, the impedance is cut in half. But how does the preamp impedance come into play?

Additionally, this is not ideal as you say, but what will happen exactly? Less bass? Highs start to distort?
 
You probably won't even notice anything! I keep telling you that nothing bad will happen. No smoke, no pops, no fizz, etc.

The most that will happen is that you may or may not like the sound.
 
You probably won't even notice anything! I keep telling you that nothing bad will happen. No smoke, no pops, no fizz, etc.

The most that will happen is that you may or may not like the sound.
Understood.

For my own understanding, I would still like to know what is going on.....as in the relationship between pre impedance and amp impedance and how exactly the sound could be effected theoretically.
 
So you want to do the math? Be my guest. :D

I have done the math and I understand it but I think its irrelevant in your case but if you are interested, then there is nothing wrong with that. :thumbsup:

EDIT: I think at this point that we are just waiting to see what you think about the sound. :rockon:
 
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OK, so what is the relationship exactly between the impedance at the pre and impedance at the amp? I understand by running the amps in parallel, the impedance is cut in half. But how does the preamp impedance come into play?
Not so much that highs distort as they might roll off and dynamics may suffer. Nothing horrible on the horizon. Give it a try.

My garage system runs a Music Hall DAC 25.3's balanced outputs with a uniform 4k output impedance into a 47k Hypex amp. Works great for me.
 
Looks like the rule is that the amp impedance should be 10 times the preamp impedance and this situation puts me just shy of that.
 
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