Are you sitting on a wealth of untapped power?

re: Are you sitting on a wealth of untapped power?

DaveB — Wed, 18 Nov 2009 22:02:06 GMT

Hi Harvey,

A quick check of your receiver's manual on Sony's website reveals no provision for bi-amping. Bi-wiring, on the other hand, should be readily available by using the A and B speaker outputs connected in tandem to your 782's high and low inputs (with jumpers removed). Just set your speaker output selector to the A+B position. Also, see my other post at http://bit.ly/bi-wiring.

Thanks for visiting us, I'm glad you enjoyed our site.

Dave

re: Are you sitting on a wealth of untapped power?

Harvey — Wed, 18 Nov 2009 12:44:55 GMT

Hi Dave,

i have a Sony STRDB930 connected to Mission 782 front 78c and 78ds

Can I biamp the fronts using A+B selection?

If not what would be the best way to biwire?

Thanks for the excellent info on this site.

re: Are you sitting on a wealth of untapped power?

DaveB — Mon, 16 Nov 2009 18:40:22 GMT

Hi Jamie,

I'm sorry my responses are appearing out of sequence with the incoming comments (you can blame me for being blog-challenged).

Anyway, your concern that your Onkyo receiver might possibly be overpowering your bi-amped Klipsch speakers is understandable. Running 260 watts to speakers rated for only 150 watts might be enough to raise any ones eyebrows. But here's why I think you're safe:

Even though your receiver has the "potential" to deliver 260 watts to each of your bi-amped speakers, the likelihood that it ever will is highly doubtful (unless you happen to have a Frat living in your basement!). That's because the volume control limits how much juice reaches your speakers. In reality, even when playing your system at levels most people would consider very loud, you're probably pushing no more than 10 watts of continuous power (believe it or not).

That means your receiver is operating well below the point where it would begin to distort. Amplifier distortion is the great killer of speakers (for reasons too long and painful to go into here). So as long as you are pumping clean power into your speakers (and resisting the urge to turn it up as far as it will go), your eardrums will probably blow before your speakers do.

In over 40 years of playing with audio gear, I have only witnessed outright speaker destruction resulting from too much clean power a handful of times (and some of those were intentional demonstrations). The other many speaker failures I've seen were the result of someone wanting more output than their amp/speaker combination could deliver, and turning the volume control way past the point of amplifier distortion.

Bottom line: If it sounds bad or badly distorted, TURN IT DOWN! (Oh man, I'm starting to sound like my father!)

Good luck and good listening.

Dave

re: Are you sitting on a wealth of untapped power?

DaveB — Mon, 16 Nov 2009 17:51:33 GMT

Hi James,

I apologize if my reply seemed curt, it was not my intention to sound like some kind of smart***.

What I was trying to say is, the relationship between power (both handling and output) and volume is complex. It depends on a great many things, including speaker sensitivity, room acoustics, and proximity of the listener to the speakers. One can scientifically predict and measure the acoustic output of a system based on these parameters, but only an individual's ear can subjectively interpret what that data means to them. How loud is too loud? How fast is too fast?

The other complication involved here is the ability of an individual to recognize the "sound" of distortion, and interpret whether it's the result of an amplifier being clipped (over driven), or a speaker being pushed too hard (even if the power is clean and undistorted), or both.

The main reason it's so hard to determine is simply this; when an amp distorts, you only hear it because it's playing through the speakers, and could easily assume that it's the speakers fault. The opposite is true as well. If the amplification is clean, yet the wattage exceeds the speakers ability to handle it to the point that distortion is heard, one might interpret the problem as being the fault of the amp. In each case, distortion is heard coming from the speakers, but the cause is different. It sometimes requires a very experienced listener with a sensitive ear to tell the difference.

Getting back to your question, James - how loud can I turn up the volume and still hear clean and undistorted sound? - I can only say that your ears must be your guide. Larger, more efficient speakers are usually the most cost effective way to play a system louder. That's because doubling amplifier power only results in a very modest 3 dB increase in volume (to play twice as loud, you would need an amp with 10X more power!), which means going the bigger amp route could get very expensive very quickly. That leaves speakers, or putting your system in a much smaller room.

You have asked some great questions, James (ones that I'm sure a lot of people have asked themselves). The difficulty in answering them is, there is no simple answer!

Thanks,

Dave

re: Are you sitting on a wealth of untapped power?

DaveB — Mon, 16 Nov 2009 16:20:45 GMT

Hi JP,

I see no reason why your new Onkyo shouldn't work with your Bose AM5 II speakers. You did tell your '707 that you were hooking up full range speakers for the front with no subwoofer, right? (Keep in mind, the Acoustimass module doesn't count as a sub; your setup would be 5.0 instead of 5.1 surround.)

Under no circumstance should you connect the cubes directly to the receiver's speaker outputs. That would bypass the crossovers in your bass module, putting your speakers at risk. Also, it would not be practical or safe to bi-amp the Acoustimass speaker system (they were just never designed that way). As for bi-amping your tower speakers, I'd be all for it if you choose to use them in front instead of the AM 5s.

Last of all, remember that soundstaging, imaging, frequency response, and so forth, depends greatly on speaker positioning and room placement. When I was in sales, I always told my customers to never be satisfied with the first place they plonked down their speakers. Getting them to sound their best is usually a matter of tweaking and experimentation. Every room (and speaker) is different.

If you still can't get everything fired up right, and you purchased your receiver from Crutchfield, don't forget that you can call our Tech Support department for some helpful advice and troubleshooting. Good luck and good listening.

Dave

re: Are you sitting on a wealth of untapped power?

DaveB — Mon, 16 Nov 2009 15:45:22 GMT

Hi Francis,

I'm afraid you have me confused. You say you have a new high-end "stereo receiver" that allows for bi-amping, and then ask if this will work with your rear speakers for surround sound (!?!).

Hmmm, I think I would need more details about your system before I could make any suggestions. Sorry.

Dave

re: Are you sitting on a wealth of untapped power?

Jamie — Sun, 15 Nov 2009 16:55:25 GMT

dear Dave-

I have a Onkyo TX-SR806 receiver (130 watts per channel), connected to a pair of Klipsch RF-82's. (each rated 150 watts)

currently both rf-82's are bi-amped( sounding better than before)

using two channels of 130 watts per tower ( per low and high) be overpowering to my klipsch towers or am i somehow looking at this situation backwards?

re: Are you sitting on a wealth of untapped power?

James Anabo — Sat, 14 Nov 2009 12:47:03 GMT

Dear Dave,

Thank you so much for your conclusive answers.

I really was distressed over onkyo not being able to pump out enough clean power and was already frustrated not having bought the marantz sr5003 just because of the thx certification fad.

I always had this idea that polk was being deceptive when they recommend amplifier power from 30 - 250 WPC. And how come at less than half of the maximum recommended power, the sound is all over the place. Doesn't make sense at all.

Your car analogy is interesting and at the same time stinging. Forgive me for being so naive. I know that you almost want to call me stupid. But a good person as you are, I know you wouldn't.

Case in fact, I want to hold on to my onkyo amp and upgrade speakers. So, if I had a hypothetically perfect speakers, and if I want to get the most volume out of the amp, how loud can I turn up the volume and still hear clean and undistorted sound?

Until I got a more powerful amp, I want to get the most power I could get from tx-sr 707.

Thank you and I am learning a lot from you.

James

re: Are you sitting on a wealth of untapped power?

Anonymous — Fri, 13 Nov 2009 04:41:51 GMT

hi Dave:

I used to enjoy my music using an Onkyo TXSV535 with a Bose Acoustimass-5 series II (front speakers connected through sub-woofer). After using this system for over 12 years with no problems , I had to replace receiver recently due to problem developed in micro-processor (as I was told) and told it would cost aprox. $300, thus replaced it with a newer version of Onkyo - SR707. with that I was still hoping to use old Bose Acoustimass5 as my front speakers and woofer until such time I buy additional speakers. The problem I am having is I cannot get the Bose system to work with OnkyoSR707.

Bose manual indicate the two cube speakers should not be connected to the amp directly except through acoustimass, and as such I am afraid to connect them directly to the receiver. I must also mention that the previous receiver worked perfectly fine with cube arrays connected through acoustimass. Could this be as a compatibility issue? Can I connect the cube speakers directly to the new receiver.

Since then I bought two tower speakers - soundstage but I kind of feel cannot match my old Bose cubes. I am also exploring the possibilities of bi-amping.

Can you please advise me. Thank you so much

re: Are you sitting on a wealth of untapped power?

DaveB — Thu, 12 Nov 2009 22:23:15 GMT

Hi James,

I'm not certain it would be fair to lay the blame specifically at anyone's feet in this particular situation. Perhaps it may be more a case of unrealistic expectations and product limitations. Let me explain:

First off, you should know that the numerical readout on the volume control of your Onkyo does not correspond to the actual decibel level (acoustic output) of your system. It's simply an arbitrary numbering scale that allows you to return easily to a particular listening level by sight. There are too many variables involved to predict how loud your system will be playing at a specific number, just as it would be impossible to say how fast your car will be going when you press the accelerator down 4.5 cm. Make sense?

Judging by the fact that you have the volume control set at 80, I can only imagine that the system is playing "very" loud. When I set my Onkyo's volume to 80, it clears out the room with sound levels approaching the threshold of pain.

You asked me at what volume you should set your receiver in order to hear clean sound: my only answer is, trust your ears more than your eyes. They alone will tell you when it's too loud, and when it's time to turn the volume down. I suspect that you have reached not only the limitations of your receiver's ability to produce clean power, but your speaker's ability to play cleanly at that level. If I were a gambler (sorry Kenny), I'd bet that it may be your speakers running out of headroom before your receiver.

I have little doubt that your receiver produces the specified levels of clean power that Onkyo claims (they are indeed a reputable manufacturer known for their high-quality amplifiers and receivers). Polk makes a fine speaker, too. I don't think it's either component by itself causing your distress, but instead unrealistic expectations as to just how loud this combination will play before distortion sets in.

Anyway, my operating philosophy has always been: If it sounds bad, turn it down. Conversely, if you must have it louder (and still be clean and undistorted), then you probably need bigger speakers and a bigger amp. Going back to my car analogy; if you want to go 180 mph, your family sedan just ain't gonna cut it (even if the speedometer tells you it will). Good luck and good listening.

Dave

re: Are you sitting on a wealth of untapped power?

Francis S — Wed, 11 Nov 2009 22:41:03 GMT

I have a new high-end stereo receiver that allows for bi-wiring and bi-amping. Here is my question: are these features do-able and/or desirable if I'm going to connect my rear speakers for 5-channel surround sound?

Thanks.

re: Are you sitting on a wealth of untapped power?

James Anabo — Fri, 06 Nov 2009 07:43:28 GMT

Dear Dave,

Why is it that when I crank the volume to 80 (absolute scale), I could hear considerable distortion from the speakers?

For nominal reference, I played Kenny Rogers' song "She believes in me" at 16 bit, 44,100 hz sampling rate, cd quality, 44.147 MB file size.

Again, this is my setup:

Receiver: Onkyo TX-SR707, 100 WPC, 8 ohms

Fronts: Polk Audio RTi A5, 20-250 WPC Amp rating, 8 ohms, Bi-amped

My question is, with that amount of distortion, my proclivity is to blame the speakers because it is them where the sound emanates from, but I'm not really sure whose fault is it?

I know that Polk Audio isn't the best speaker out there which is entirely different from Onkyo's perspective as they are being recommended even by the top speaker manufacturers such as HSU Research.

What I'm asking, and what I am believing at the moment, is: can Onkyo receivers pump out clean power even at 100% of their available volume without distortion?

Let's look at my case again, I cranked the volume to 80 and I could hear Kenny Rogers' throat being ripped open.

I set the volume setting to absolute, which, based on my own interpretation, translates to actual decibels to mean that 1 on the scale means 1 dB and 50 means 50 dB and 100 means 100 dB.

If I were wrong, why would Onkyo, a respectable amp manufacturer, include things that do not really perform up to their reputation? It would have been better for them to be honest, saying explicitly that "Our amplifiers can only handle this much power", even if they reduced the maximum volume.

I cannot say for sure about polk speakers, I could not even look at them right now.

Please enlighten me on this matter as I am losing interest in my setup.

Please also tell me at what volume should I set to maximum so that i could hear a clean sound (or that the amp feed a clean power)

One more thing, I added 2 dB on fronts so that they would be a little audible than the sub, which is at 0 dB in amp.

re: Are you sitting on a wealth of untapped power?

DaveB — Fri, 30 Oct 2009 20:01:23 GMT

James and Ray,

Thanks for your feedback. This is good information. Both of your experiences help point out the variability from brand to brand, and system to system that folks are likely to come across when exploring system tweakage, including bi-amping.

I think the take away from all this is: Always be considering ways you can improve the sound of your system. And don't be afraid to experiment with making changes, especially ones that are easy and relatively inexpensive (or even free), such as speaker placement, crossover settings, bi-wiring, bi-amping, and cabling.

Dave

re: Are you sitting on a wealth of untapped power?

Ray K — Thu, 29 Oct 2009 04:01:40 GMT

Hi Dave, I have read this post with great interest and followed your advice. I have a Yamaha RX-V663 set up in 5.1 with Polk Monitor 70's as my fronts. My setup is for HT and 2 channel music . I do not care to use a subwoofer for my music, so the front's bass response is important.

Bi-amping has made the speakers really sing. Much more detailed and tight. Here is some advice for anyone bi-amping with a 663. Connect the front L & R to the low pass and the surround back to the high pass. My speakers are set to large and it appears that the speaker setting does not follow the redirected channels. Wired with the front L & R to the high pass will result in in a loss of bass as if they were set to small and crossed to a sub.

In closing, I would like to thank you for the information you have made available.

re: Are you sitting on a wealth of untapped power?

James Anabo — Fri, 23 Oct 2009 14:44:59 GMT

Dear Dave,

Sorry for not having seen your answer sooner.

Also, sorry if it looked like i overanalyzed a simple problem. I guess I was just too excited.

Anyway, thanks a lot for your inputs and it seems like I gave you a hard time over a basic setup.

Regarding my question 4, it is just what I needed to hear. Although one thing I observed is that at lower volumes, the sound seems undefined, like in the range between 1 and 40, I could hardly make up the sound. I needed to crank it up more than halfway the maximum volume in order to get a decent definition of the audio, something like between 55 and 75. Is it because of the bi-amping, which gave it a lot more power?

By the way, I changed my mind and got the TX-SR707 instead.

Your recommendation of 80 Hz or lower for crossover point is excellent. I was wondering before why there was too much boom in the music no matter what adjustment I made. It was because I set the crossover to 120 Hz and that the simple bass signals were channeled to the subwoofer which unnecessarily amplified them.

Thank you very much Dave. I really appreciate it.

Best regards,

James