Is it safe to amplify the main output of a receiver...

[Denis29]

Hello folks,

I have an Onkyo DR-UN7 DVD Receiver, and right now I'm just using it with the 2 native Onkyo speakers and a powered Onkyo Subwoofer.

I decided I'd like to replace the 2 main Onkyo speakers with Axiom M3 speakers, but I wanted to be able to give those Axioms more juice... The Onkyo unit has a built-in amp that powers the 2 main channels and also has 4 pre-amplified outs (2 surrounds, a center speaker, and a subwoofer).

In my case, I am looking to juice up the main 2 channels, not the pre-amped outs... The built-in amp has the following specs:

16W + 16W at 8 Ohms, 1 kHz, FTC
23W + 23W at 4 Ohms, 1 kHz, FTC
Damping factor: 70 (front, 1 kHz, 8 Ohm)
Input Sensitivity and Impedance: 150 mV/47 kOhm (LINE)
Output Level and Impedance: 120 mV/2.2 kOhm (REC OUT)
Signal-to-Noise Ratio: 100 dB
Speaker Impedance: 4 Ohm - 16 Ohm

I was thinking about getting an Onkyo M-282 2-channel Power Amp and just connecting it to the receiver in place of the 2 main speakers, and then connecting the main speakers to the M-282 instead. Is it plausible and safe to do, or might that damage the receive in one way or another?

The manual for the Onkyo receiver talks about hooking up a power amp to the pre-outs, but I wasn't able to find anything about amplifying the MAIN speaker channels, and whether it's basically the same thing or not and if it has something to do with the bridgeability of the receiver's amp...

I'm a noob, so I appreciate your patience Any help appreciated!

 

[skizzerflake]

Hello folks,

I have an Onkyo DR-UN7 DVD Receiver, and right now I'm just using it with the 2 native Onkyo speakers and a powered Onkyo Subwoofer.....
The manual for the Onkyo receiver talks about hooking up a power amp to the pre-outs, but I wasn't able to find anything about amplifying the MAIN speaker channels, and whether it's basically the same thing or not and if it has something to do with the bridgeability of the receiver's amp...

I'm a noob, so I appreciate your patience Any help appreciated!

Do NOT connect another amp to the speaker outputs unless you want a dead amp. Like the manual says, you can hook up to a pre-out but unless an amp is specifically built for it (few ever have been), you would be really lucky to only blow a fuse or trigger a shutdown. A power amp can produce only certain amount of power and boosting the input above what's intended would not boost the power amp's output anyway. It would either drive the input stage into severe distortion or burn out those transistors.

 

[mtrycrafts]

I think you need a new receiver as well. You can get some for not that much $$.
You need a pre amplified output signal for use with a power amp. Since that doesn't seem to have one for the main channels, you are out of luck.
16 watts is not much power at all for the Axioms.

 

[Denis29]

Sigh... That's what I was afraid of, too - plugging an external amp to the main speaker channels just didn't sound right. I'd hate to blow up such a nice little receiver.

See, I am really happy with the Receiver itself - it plays just about any conceivable disc format, which is why I bought it, and it is capable of the 5.1 surround home theater set up. When I listen to my music on my Beyerdynamic headphones, the sound is excellent, with very good detail and nice bass - I really have no complaint about that...

I just wanted to improve the 2 main speakers somehow. They are 4 Ohms each, while most speakers of that class seem to be 8 Ohms, which halves the power going to them... 16W really isn't much to work with... I doubt the Axioms would be useful to me on the surround channels...

 

[Seth=L]

You could just get a full size receiver like a Pioneer vsx-516 for less than $200.

 

[Denis29]

You could just get a full size receiver like a Pioneer vsx-516 for less than $200.

But how will that let me use my Onkyo receiver? I think we're talking a whole new audio system here...

I'm not looking for best of the best on my budget, but I do wonder if a different set of speakers, for instance, might improve the system. For instance, the Bose 301 V maybe, if Axioms would not do well with the Onkyo unit. Maybe I should be posting about this in the Speaker section of the forum...

 

[Nick250]

You would be better off spending the money you would spend for the amplifer towards a low price receiver. Same money, but superior results with the new receiver. No brainer IMO.

Nick

 

[Denis29]

You would be better off spending the money you would spend for the amplifer towards a low price receiver. Same money, but superior results with the new receiver. No brainer IMO.

Nick

Yea, I'd rather look for a solution that involves keeping the Onkyo receiver. I guess I won't worry about getting an amp at this time but just replace the speakers and see if that makes any significant improvement...

Thanks to all for the input about the amps/receivers...

 

[jcPanny]

New speakers

Denis,
If you want to hold on to the Onkyo system for a while, you should consider some speakers with horn loaded tweeters like the Klipsch reference series. Their high efficiency allows them to play louder with less power.
Here is an AH review that includes axiom and Klipsch bookshelf speakers:
http://www.audioholics.com/productreviews/loudspeakers/SpeakerFaceOffVIp1.php

 

[markw]

you're trying to lower the river instead of raising the bridge.

Yea, I'd rather look for a solution that involves keeping the Onkyo receiver. I guess I won't worry about getting an amp at this time but just replace the speakers and see if that makes any significant improvement.

It'll be cheaper in the long run to upgrade the receiver. Finding speakers that are extremely sensitive will limit your choices tremendously. They are out there, but some can get mighty pricey.

What JCP suggests is one good alternative, but you really should listen to speakers before making a final judgment. Just because a speaker is sensitive doesn't guarantee you'll like it's sound.

With more power you open up your choices. And, nowadays, it's cheaper to upgrade receivers than speakers.

Finally, if you really, really want to keep the headphone output of the oinker, you could always run an interconnect from the tape out of your new receiver to an aux input on the oinker. That way, you'll be using it as a headphone amp.

 

[Seth=L]

You can use the Onkyo as your source. It has a digital output does it not?

If you get a new receiver, you can connect it to the Onkyo.

 

[Nuglets]

They do make a device that will take a regular speaker level signal and convert it to a pre-out signal. It is made for car audio but I have successfully used it in my Home audio setup until I got a receiver with pre-out's. Not the best option, but it is cheap and will suffice for the time being. Right now I can't find it anywhere to tell you the model, but if you search you should be able to find one.

 

[Denis29]

The Onkyo doesn't have a digital out, regrettably... It has only a digital IN.

I think I'll just try out some speakers on it and see how much better it gets. When I bought the Onkyo a year ago, it was already a big step-up in sound for me - I didn't know much about audio set-ups, pre-amps, amps at that time and considered it enough of an upgrade. Live and Learn.

It doesn't sound "bad" stock... But I do want to see how I can improve. I think I'll go with Axioms - they have a 30-day risk-free return policy, and then I can listen to them on my system... If I won't have enough improvement, I can always return them...

 

[f0am]

They do make a device that will take a regular speaker level signal and convert it to a pre-out signal. It is made for car audio but I have successfully used it in my Home audio setup until I got a receiver with pre-out's. Not the best option, but it is cheap and will suffice for the time being. Right now I can't find it anywhere to tell you the model, but if you search you should be able to find one.

I beleave cardomain has them.
Ive used those in the past befor too. They work well, but they are also touchy and you do loose alot of quality that way.

I think this guy doesnt want to get rid of his receiver because he feels he paid for the best.
Look at it this way, why would you buy new speakers for your receiver that cant handle anything over 30 watts... Thats rediculous. You need to first buy a reciever that can push atleast 100 watts per channel then upgrade the speakers.

 

[Denis29]

I think this guy doesnt want to get rid of his receiver because he feels he paid for the best.

You're right... Well, it was like $350 a year ago... I guess you get what you pay for with the functionality it offers...

Anyhow, I did read the comparison reviews on this website for the several bookshelf speakers... Axioms sound like a good option. Although I'd be very curious how Bose 301V or Klipsch would sound on my Onkyo... I guess I'll just have to try and find out... Not looking for Mt. Olympus here, just a little improvement

 

[Nuglets]

If you are looking for some improvement I think a new set of speaker's will be satisfying. If you like to listen to your system very loud, then you will be in the same predicament you are in now if you just get new speaker's. Depending on the size of your room you may not enough power to make the speaker's play as loud as you would prefer. If loudness is what you want, then you should consider a new receiver with more power or add an amp using the adapter I mentioned in a previous post. If you are just looking for a different sound, then a speaker upgrade will be exactly what you need and then perhaps more power in the future.

The easiest way for us to give you the best advice in my opinion is to find out why you wish to upgrade. What is your system lacking(in terms of sound) in your opinion that makes you want something new?

 

[Nuglets]

I beleave cardomain has them.
Ive used those in the past befor too. They work well, but they are also touchy and you do loose alot of quality that way.

I think this guy doesnt want to get rid of his receiver because he feels he paid for the best.
Look at it this way, why would you buy new speakers for your receiver that cant handle anything over 30 watts... Thats rediculous. You need to first buy a reciever that can push atleast 100 watts per channel then upgrade the speakers.

I didn't experience any loss in sound quality when using the device, but considering the fact that the thing is rated for 35WRMS and my receiver was putting out more than 100 at high sound levels, it caused the device to become so hot it actually began to change shape. In the current scenario I wouldn't foresee that happening due to the power rating on Onkyo being not far above the rating of the device.

 

[Seth=L]

Although I'd be very curious how Bose 301V or Klipsch would sound on my Onkyo.

Definetly no Bose, please for your own good, no Bose.

 

[Denis29]

The easiest way for us to give you the best advice in my opinion is to find out why you wish to upgrade. What is your system lacking(in terms of sound) in your opinion that makes you want something new?

Good point.

I am not actually looking to make my current set up any "louder" because as it is - Onkyo packs enough punch for my relaxed listening, and it's pretty dang loud even at half-volume. Even with some ~ 30 W per channel.

I am looking to refine the sound, basically. I think the stock speakers are "pretty good", but the highs could certainly be clearer, and the bass punch is outright missing without the subwoofer, to the point where Miles Davis' "Kind of Blue" sounds king of flat. Metal sounds pretty flat too because the bass frequency range simply does not come through. My subwoofer does well to compensate that, but I want the speakers to be able to output full range of sound, which I can then compliment to my liking with the subwoofer that I have.

The stock speakers are Onkyo D-720, 4-Ohm rated, with max input power of 70W. Output sound pressure level 82 dB/W/m, Freq response of 50 Hz - 35 kHz, X-over Freq 6.5 kHz. Woofer is a 13-cm A-OMF cone (5.11-inch), and the tweeter is a 2.5-cm (1-inch) soft cone.

I read the comparison article for the bookshelf speakers on this site, which I found very helpful. It looks like 4-Ohm rated speakers are quite tough to find, but I guess 8-Ohm ones should do alright. I'd say I *usually* have music playing at mid-volumes to low volumes, and only sometimes do I play it especially "loud". So I am more concerned with having speakers that will give me a full-range sound at those volumes than I am with making my system "loud".

Are Axioms reasonably efficient speakers, or would Klipsch be a better choice for my purpose and with this system? For some reason, as soon as I read about the Axioms and checked out the Axiom website, I immediately liked them

 

[Nick250]

You're right... Well, it was like $350 a year ago... I guess you get what you pay for with the functionality it offers...

Anyhow, I did read the comparison reviews on this website for the several bookshelf speakers... Axioms sound like a good option. Although I'd be very curious how Bose 301V or Klipsch would sound on my Onkyo... I guess I'll just have to try and find out... Not looking for Mt. Olympus here, just a little improvement

The only way to know what might sound good to you is to start auditioning. Grab you favorite CD and head out to hear every speaker you can find in your price range. Reviews are certainly helpful to perhaps narrow down the possibilities, but they are no replacement for a personal listen with your very own ears.

Nick