Bi Wire RTi4

awalwah

Hi guys,
I own RTi4 speakers which capable to be bi wired. Unfortunately i do not have biwired speaker cable. My amplifer has 2 set of speaker connection A and B. Can I connect 2 set of set of speaker cables from amp to my speakers back and removes the jumper plates. Is this consider bi wire practice to, and can the sound quality improves?

Outfitter03

If you connect the way you are describing to your amp, you will most likely drop the speaker impedance from 8 ohms to 4 ohms. This will place a place a larger load on the amp and depending on make may result in overheating/reduced performance. If you want to bi-wire it would be better to buy adapters to hook both sets of wires to the same binding posts. Do you own two sets of speaker cables and if so what are they terminated with? Bananas or spades?

If you want to remove the jumpers and have one quality set of cables this is an inexpensive alternative.

http://www.anticables.com/jumpers.html

Outfitter03

Keiko you are correct in saying the speaker impedance doesn't change. The physical impedance of the speaker to be specific.

But the impedance that the amp or receiver sees may change depending on how the output of the amp is wired to the second set of binding posts. On some amps/receivers this may place two parallel circuits on the amp.

This is not true if both speaker cables are going to the same binding post as they do with a biwire pair of speaker cables, but that is not what I read in awalwa's post.

I have a Denon DRA-295 that has an A and B speaker connection as awalwa described. Both A and B speaker connections may be used at the same time but it drops the impedance that the amp sees by 50%.

My manual cautions only using both sets of binding posts with 16 or 8 ohm speakers. 4 ohm speakers are acceptable when one set of posts are used.

No biggie, just wanted to clarify that I believe I am not suffering from a "GCE" gross conceptual error.:):cool::)

John K.

Awal, welcome to Club Polk. You're in fact fortunate that you haven't blown money on bi-wired speaker cables. Yes, the use of the A and B terminals with the jumpers removed does result in bi-wiring, but no, it can't improve the sound quality. The claimed benefits in the Brilliance Hifi article linked are a nonsensical exercise in pure fantasy. Bass frequencies don't "overpower the delicate treble". These frequencies happily coexist throughout the recording process and are amplified in the same output transistor in your receiver. They aren't separated until processed by the the speaker crossover. Separating the wires at the receiver output rather than inside the speaker enclosure, which usually is what takes place, can't change this.

John K.

Outfitter, maybe not a "GCE", but still incorrect. The A and B terminals are in fact just a parallel connection to the same output channel, but the effect is different when connecting to two separate speakers as compared to separate high and low frequency sections of the same speaker. Connecting to two 8 ohm speakers in parallel does result in a net 4 ohm load(at those frequencies where the nominally 8 ohm speakers do actually have an 8 ohm impedance). Connecting to the separate high and low frequency sections of the same speaker doesn't result in the amplifier "seeing" two 8 ohm loads in parallel. Slightly oversimplified, the effect of the crossover is to make the impedance in the other frequency range much higher than in the range that it is for the frequency being played at that instant. For example, if 100Hz is the signal being handled at 8 ohms in the bass section of the crossover, the treble section of the crossover will process that 100Hz at a much higher impedance(say 80 ohms), because it has high resistance to low frequencies. Since the reciprocal of a parallel impedance is the sum of the reciprocals of the individual impedances, the result in this example would be 1/8 + 1/80 = 1/X, 10/80+ 1/80= 1/X, 11/80 = 1/X, X= 80/11, X= 7.3 ohms(not 4).

Also note that connecting the two wires to one terminal is just as much a parallel connection as is connecting them to the A and B terminals. The A and B connection is just parallel a couple of inches farther back inside the receiver.

Outfitter03

Thanks John K. for going into detail with your explanation including the formulas and calculations. I don't want to hijack this thread so I will just say, "I get it now"!!!

awalwah

Thanks all, now i has learned a bit from your explaination and theory. I dont wanna risk and damage my speakers by doing so. So my next project is to save some money for a quality bi wired cables as described. Anyway my amplifier is Audiolab 8000s and Marantz 6003 cd player. Just budget stuffs.