Connection the Pioneer SC-LX90 Bi-Amp Doubt?!

bi-amping or bi-wiring?

if bi-amping, yes, you should change to one of the biamp modes (5.2 or 7.2 bi-amp) but if bi-wiring, 2 cables on the same amp output speaker terminals, then I think you should stay with normal because the bi-amp setting won't accomplish anything. bi-amp setting dedicates the 2nd pair of amps but you have to connect the 2nd pair of cables to the 2nd set of amps

your post isn't clear what you are doing exactly because you haven't stated whether you are connecting to the 2nd set of amps or just doubling up wire. at least it isn't clear to me

damage? how can anyone say - don't know your speakers, their power rating, their efficiencies or rated impedances. however, it is highly doubtful you can actually damage them from bi-amping if they have the 2nd set of terminals. most damage is from clipping (too little power at peaks) and not too much power.

this has been discussed in countless threads countless times....this is passive bi-amping and the real world benefits are marginal anyway. what are you trying to accomplish? a real benefit can come from active bi-amping where you replace the speaker's internal crossover network with a separate external crossover box, either adjustable or fixed, and use that instead. The Susano does not do active bi-amping. The added power from passive biamping can only add a few dB of output. Unless your speakers are very low efficiency, like my own Magnepans, you are running out of headroom, meaning your normal listening volume is high (say -5 dB or more) or you are sensing that the amps are going into clipping (harsher sound, distortion, or amp shut-off) then you can just turn your volume up 2-3 dB and accomplish the same thing as passive bi-amping. I don't have time to get out the math but it has been posted thousands of times in many many threads, including the SC-09/SC-LX90 thread I started years ago

it certainly has been posted recently in Pioneer & Denon threads because it keeps coming up all the time with the same people telling folks that it doesn't make a significant difference if you aren't clipping at high volumes now & have the extra headroom

your choice what you want to do with your Susano, but if you're asking if you made the correct connections...I can't tell from your post. If you're asking if it will damage your speakers, that depends on if they are designed for it & their power handling capability. it's highly unlikely but you should check the mfg's info & FAQ's for your speaker models to be sure they are "rated" for the power, assume double the rated amp power - 280 watts @ 8 ohms.
Edited by ss9001 - 12/29/12 at 8:55am

Passive bi-amping will not "separate" the highs from the lows. Save your money that would be spent on additional speaker cables and wire it up normally.
Passive bi-amping is just a marketing gimick.

It's your money to waste and since you've already spent it....

"Bi-wire" connection to the AVR is from the same single set of speaker posts whereas "Bi-amp" connection is from two sets of speaker posts.

Passive biamping and bi wiring probably run neck and neck for which makes less sense on technical and sound quality grounds. Since you can waste more money on passive bi-amping, I'd give it the lead in this contest of which is the bigger waste of time and money.

+1

Two different configurations with most likely the same results.

Expectation bias

I have to agree with what everyone is trying to tell you. as I stated, bi-wiring and bi-amping are not the same thing and passive bi-amping and active bi-amping are not the same thing nor give same results. of course you can't tell the frequencies apart, there's nothing in the receiver to separate the frequency band into multiple parts for sending individually to your tweeter, wooder & mid-range. The Susano is passive bi-amping.

what you "hear" is perhaps a minor increase in volume by having 2 amps connected, but even at that, you'd have to be listening pretty loud for it to make a difference. or expectation bias...you expect it to sound different because you paid the money for expensive cable or adding amps so it does

I mentioned the math shows that even if you assumed the most optimistic results that biamping increased the power from 140 to 280 max output, it doesn't make that much difference in volume:

dB difference = 10 x LOG(power1 / power2)

Assume 140 watts per channel normal and 280 watts bi-amped:

dB difference = 10 x LOG(280/140) = 3 dB

1. 1 dB is considered the least perceptible difference
2. it takes 6 to 10 dB to be perceived as twice as loud
3. the most optimistic bi-amp result is at MAXIMUM power, which would only be the case on dynamic peaks that last fractions of second to a second maybe. during normal listening at low levels, the difference in volume would be even harder to distinguish.
4. you can accomplish the same thing by turning up your volume knob 3 dB. as long as you aren't already going into clipping or at high volume levels to begin with.
5. Klipsch RF-7 speakers are so efficient at 101 dB/meter @2.83 volts!! that it would take far less power than the Susano amps in normal mode to deliver VERY LOUD levels without any bi-amping at all. My speakers on the other hand, are only 85 dB/ meter efficiency so they do take a lot more power than your Klipsch's to give same volume level. You don't even need the normal power capability of the Susano to drive yours
6. are you aware that the power supply in the Susano is capable of 1400 watts total? meaning it's individual amp channels are rated at 140 w X 10 channels. but, it is quite capable of exceeding that power rating at 5 & 7 channels driven. Home Theater Magazine bench tested it in 2008:

I quote:

"With five channels driven continuously into 8-ohm loads, the amp reaches 0.1% distortion at 199.4 watts and 1% distortion at 267.3 watts.

With seven channels driven continuously into 8-ohm loads, the amp reaches 0.1% distortion at 198.6 watts. I was unable to measure the power level at 1% distortion because the protection circuit engaged before it reached that level. It reached the manufacturer's stated distortion of 0.05% at 181.1 watts, which is not all that far from the 200 watts specified by Pioneer.

In other words, it's a 200 X 7 power capable ampflier! How much power do you think you need to drive those 101 dB efficient Klipsch's??

Bottom line, with those Klipsch speakers, you are "wasting" your time passive bi-amping. If you had an all Magnepan speaker setup, it might be justifiable, but really not in your case. you are free to experiment and try different things with your gear, I don't think anyone begrudges you for trying things but we are giving you the objective side of the argument as a counterbalance to the subjective side - is what you think you hear real or significant.

if you think you are hearing "better" sound, and want to justify passive bi-amping as done in the LX90 or bi-wiring because of some audiophile urges, you are free to do so you wanted to know about speaker damage. if you bothered to read your own speaker manufacturer's specs on their website, you'd know the answer ....no, the RF-7's have a power rating of 250 watts rms to 1000 watts peak - clearly says that on the product sheet. so, did you really need to ask?

I am just adding to the objectivity that already been presented to you.

BTW - once upon a time, I had a Sansui quad receiver (still do actually:o) that had a double power switch for 2 ch mode. it went from 4 X 60 wpc to 2 X 120 wpc. Yes, it was slightly louder at the same volume knob setting but by no means was it anywhere close to twice as loud. And I was driving Magnepan speakers off it even back then so taxed the receiver hard so at the loud levels I listened to, one could expect to hear a slight volume increase from doubling the amp power: the VU meters on it would spike sometimes at the 40-60 watt mark. so I do know a bit from practical experience that the math doesn't lie
Edited by ss9001 - 12/30/12 at 7:03am

and if you still want to bi-amp (as opposed to bi-wire), you'll need to change your speaker-amp setup in the setup menu from Normal Surround to either the 5.2 All Bi-amp or the 7.2 Front Bi-amp speaker options, depending on whether you are bi-amping all speakers or just the front 3. and connect your bi-wire cable so that 2 amps are connected not just double up connections on one set of amp terminals.