Bi-amping floor speakers (1 Viewer)

[tdew]

I have an Onkyo Ht-550 receiver. It came with an in the box home theater setup. The whole setup has good sound, although I am no audiophile. The receiver outputs 1035 W, so it has plenty of juice to power the 7.1 surround sound setup. I upgraded the subwoofer to a larger, more powerful one just because the bass was not getting enough punch, but now I am now looking at a pair of tower speakers and they have something called a bi-amping feature. My receiver does not have this feature, and I am wondering if I do not do this, will it hurt my sound quality or volume that it can output. The subwoofer that I upgraded to has a built in amplifier in it, so could I use that? or is this not a big deal?
Any helpful information on this would be greatly appreciated, as I am kind of a novice to this. I am primarily interested in music sound quality if this helps guide your feedback.

 

[gene c]

In reality, it's more like 500 watts with all 7 channels but that's about what all receivers in that price range output. Sometimes they fudge the numbers to keep up with the Jones.
Bi-amping might be usefull if you have very high-end speakers and large, seperate amplifiers, otherwise don't even think about it. Again, the manufactures just add the bi-amping posts to keep up with everybody else. Even if 99 % of the consumers never use that feature. If you want good volume then look at the speakers sensitivity rating or SPL. For a tower speaker a rating of 88 or 89 would be about average with 93-94 on the high side. Bookshelves run about 85 to 87. The higher the number the louder the speaker will sound at the same wattage. In theory, a 3 db higher rating equates to twice as loud be in reality it's not quite that much of a difference.
Definently use the amp in the subwoofer. It takes some of the strain off the receivers amp. Using a coaxial cable from the "SUB OUT" on the back of the receiver to the LFE input on the subwoofer wil use it's internal amp.

 

[Soundjunkie1977]

If it was purely for music purposes I would go ahead and bi wire or bi amp the towers off of two of the back surround channels. Just run the left back surround to the the top set of connections of the speaker connections on the back of the tower, Do the same thing for the right side, all you are doing is splitting the highs and lows up as the go into the speakers. if you are just playing music with the receiver on all channels stereo or mono it may help it but its not gonna hurt anything. But yeah all speakers worth a crap at all are gonna be bi wire or bi amped capable.

 

[David Willow]

Actually, you are NOT splitting anything. The crossover is still INSIDE the speaker. The amp is still inside the AVR with one shared power supply.
Bi-amping in this manner is pretty much pointless.

 

[Mr645]

I don't think it would be worth while to bi wire anything when using the receiver from a HTIB system, spend the money on better speakers.

 

[John Garcia]

Could we just sticky a thread about bi-amping maybe? This is one of the most misunderstood topics and seems to be a very common question these days.

Actually, you are NOT splitting anything. The crossover is still INSIDE the speaker. The amp is still inside the AVR with one shared power supply.
Bi-amping in this manner is pretty much pointless.

100% correct. This is passive biamping and you are still sending FULL RANGE signal to both portions of the speaker (nothing is "split" except the connections), the crossover is being done by the speakers itself. The demand on the power supply is the same and what is delivered to the speakers is effectively the same once the speaker filters it out. So, other than manufacturers wanting to show that they have this feature, I don't see it as actually having any benefit to the consumer in the real world.

 

[Al.Anderson]

The demand on the power supply is the same and what is delivered to the speakers is effectively the same once the speaker filters it out.

I don't follow that part. If a receiver with discrete amps uses two channels for a speaker I'd expected to get more power to that speaker. So if I was driving stereo with four channels bi-amped, why wouldn't I get more volume than with just using the two? (Mind you, I think this is rarely a benefit, but I'm still curious about the power bit.)

 

[Mr645]

If you bi amp, use two channels instead of one, yes, your delivering double the power, and that should add 3db more volume.
If the speakers allow for it, it is likely there will be sonic improvements from bi amping, or bi wiring the speakers. The crossover in the speaker has to be designed for it. Some speakers require multiple channels and sometimes the crossover even goes between the pre amp and the amp.
Most typical bi amp setups to send the full range signal to all channels, all sections of the speakers, but crossover prevents the full range from reaching all sections of the speakers.
A decent external amp should be able to deliver it's full output when all channels driven, full range. Unlike most receivers that simply don't have the power supply to do that. There is a reason why an external amp is heavier then a receiver, even one rated more powerful. Most of that weight is in the power supply that handles the 120v AC coming in. Often just having the greater power and headroom from an external amp makes a big difference and that's why a bi amped set up sounds better.

 

[John Garcia]

The demand on the power supply is the same and what is delivered to the speakers is effectively the same once the speaker filters it out.

I don't follow that part. If a receiver with discrete amps uses two channels for a speaker I'd expected to get more power to that speaker. So if I was driving stereo with four channels bi-amped, why wouldn't I get more volume than with just using the two? (Mind you, I think this is rarely a benefit, but I'm still curious about the power bit.)

If you bi amp, use two channels instead of one, yes, your delivering double the power, and that should add 3db more volume.
If the speakers allow for it, it is likely there will be sonic improvements from bi amping, or bi wiring the speakers. The crossover in the speaker has to be designed for it. Some speakers require multiple channels and sometimes the crossover even goes between the pre amp and the amp.
Most typical bi amp setups to send the full range signal to all channels, all sections of the speakers, but crossover prevents the full range from reaching all sections of the speakers.
A decent external amp should be able to deliver it's full output when all channels driven, full range. Unlike most receivers that simply don't have the power supply to do that. There is a reason why an external amp is heavier then a receiver, even one rated more powerful. Most of that weight is in the power supply that handles the 120v AC coming in. Often just having the greater power and headroom from an external amp makes a big difference and that's why a bi amped set up sounds better.

Not sure I follow all of that answer, but yes, though those channels in the receiver are discrete, they are ALL powered by the same power supply. So even though you have 4 separate channels going to two portions of each speaker, they are all sharing the same power supply. A receiver is typically rated at its power for TWO channels only, when you have demand on more than two, the total output drops because the power supply can only supply so much TOTAL power. As more channels require power, the total amount that each has available is reduced. Though each portion of the speaker is drawing less actual load, the speaker as a whole is still drawing the same amount of current from the receiver. Each of those channels is still amplifying all of the signal that was sent to it, thus actually doing more work, work that is being filtered out by the speaker's passive crossover.
True passive bi-amping would mean either horizontal or vertical configuration of separate amps. You either have one 2ch amp for one speaker - one to high and low = vertical, or ch A from each of two separate amps going to the highs and channel B of each going to the lows = horizontal. With vertical, you will get different loads on the two channels, while with horizontal, each individual amp will be handling a more similar load on each channel. With a receiver, it is neither of these because there is only one power supply.
Active bi-amping is filtering the signal before it is amplified. In order for that to work, many say the passive crossover in the speaker should be bypassed then.
Bi-wiring is absolutely pointless. Running two separate wires from a single channel to each portion of the speaker does nothing at all.