Bi-wiring/Bi-amping explained

Krazyz1

Since this started out a explanation of bi-wiring/bi-amping , here is my scenario. Some speakers you can hear a difference when bi-wired. On my RTiA9's made a big difference. The only way I can describe it is that the music sounds meatier or more robust. Not just my oppinion , others that had heard it before and after agreed.This is the part where I be come un-educated and need some education from people in the know. Does the amplifier read the ohm value still at the rated 8 ohm , or bi-wired does the amp see it as a 4 ohm load?????? I don't know and this is what got me wondering. For sake of argument a ROTEL RB-1090 will support 4 speakers in standard wiring mode , but will only support 2 if bi-wired. Why???????

sTiLlLeArNiNg

TBH Krazy i think the biggest improvement come's from removing the stupid jumper bar's that come on all 4 post speaker cabinet's and using speaker wire

I'm currently trying to build some cable's based off of Canare's 4s11 which is a 4 conductor cable, i will be pairing up the lead's on the AMP/AVR side and running each separate lead to the corresponding terminal's on the speaker side. I have pretty much everything i need except for the terminal's which i hope to get ordered this week or early the following week

I'm not shure but i think with your Rotel example you would be bi-amping and not just bi-wiring I would assume that there would be more noticeable gain from bi-amping vs bi-wiring

I still beleive that bi-wiring produce's noticeable improvement's and i beleive those improvement's vary depending on the speaker :cool:

Trying to bi-wire/bi-amp is not very costly IMO (provided you have the 2nd amp for bi-amping) as you can get Canare 4s11 (which is very highly reccomended by many people) usually for $1.19/ft - $1.39/ft and since you are in the state's most companies offer free shipping to lower 48 sate's on order's over $100

Krazyz1

I agree with most of what you are saying , but if you go to Rotel home page and go into archive downloads it shows distinctly on the rear panel wiring 4 speakers hooked up 2 strand only and also only 2 speakers wired to it that are bi-wired. I fully understand the difference between the 2. Bi-wiring is removing jumper bars at speaker terminal and running 2 set of speaker wires to amp and the you have 2 + cables on red term. and 2 - wires on black term. Bi-amping is essentially the the same EXCEPT each cable would be connected to seperate amps. If I am in error feel free to correct me. Still no answer on ohm issue that is my biggest curiosity.Because if your speakers are essentially rated 8 ohm and because non stand wiring might make the amp read 4 ohm , I would think that would open the door to over power your speakers since amps have 1 rating @ 8 ohm and 4 ohm almost always higher. That's why the ohm issue is important to me. I don't want to think I am only shoving 200w. because 8 ohm , where in reality I might be running 350w. because I DON'T know if amp reads the load different because of bi-wiring. Someone please clear this up for me. Thank you.

TECHNOKID

Krazyz1 wrote: »

I agree with most of what you are saying , but if you go to Rotel home page and go into archive downloads it shows distinctly on the rear panel wiring 4 speakers hooked up 2 strand only and also only 2 speakers wired to it that are bi-wired. I fully understand the difference between the 2. Bi-wiring is removing jumper bars at speaker terminal and running 2 set of speaker wires to amp and the you have 2 + cables on red term. and 2 - wires on black term. Bi-amping is essentially the the same EXCEPT each cable would be connected to seperate amps. If I am in error feel free to correct me. Still no answer on ohm issue that is my biggest curiosity.Because if your speakers are essentially rated 8 ohm and because non stand wiring might make the amp read 4 ohm , I would think that would open the door to over power your speakers since amps have 1 rating @ 8 ohm and 4 ohm almost always higher. That's why the ohm issue is important to me. I don't want to think I am only shoving 200w. because 8 ohm , where in reality I might be running 350w. because I DON'T know if amp reads the load different because of bi-wiring. Someone please clear this up for me. Thank you.

Your question is not an easy one as speakers are wired differently from brand to brands. IE: many Polk speakers will give you a higher impedance when the jumper are connected since the Xo provides for high impedance input however, when the jumper is/are removed, you will read the 8 ohms impedance at one set of speaker connector/leads while you still read high impedance at the other set. Even without elaborated Xo, you still read only 8 ohms no matter what because there is always some capacitors to isolate drivers from each other in order to avoid impedance drop with drivers connected in parallell (this is also basic Xo principle as the capacitor are chosen to pass specific frequencies while blocking others). Your best bet is to simply use a multimeter to check how your specific speaker reacts when you measure them without the jumpers. Personally, in order to read a change in impedance value when removing the jumpers would lead me to believe the speaker has a piss poor design. As I pointed out, your best bet is to experiment by measuring how your specific speakers react when you do remove the jumper. In fact, my personal opinion is that upgrading your Xo is a much better improvement and investment than wasting time and money on cables in order to bi-amp.

Cheers!
TK

WilliamM2

Still no answer on ohm issue that is my biggest curiosity.Because if your speakers are essentially rated 8 ohm and because non stand wiring might make the amp read 4 ohm , I would think that would open the door to over power your speakers since amps have 1 rating @ 8 ohm and 4 ohm almost always higher. That's why the ohm issue is important to me.I don't want to think I am only shoving 200w. because 8 ohm , where in reality I might be running 350w. because I DON'T know if amp reads the load different because of bi-wiring. Someone please clear this up for me. Thank you.

Bi-wiring is just moving the jumper from the speaker to the amp terminals. It won't change the load on the amp at all.

TECHNOKID

WilliamM2 wrote: »

Bi-wiring is just moving the jumper from the speaker to the amp terminals. It won't change the load on the amp at all.

Humm, that's an interesting way to put it (and also very easily understood also )!

Cheers!
TK

CoolJazz

...and to clarify for the record, as established before, using a voltmeter does not tell you the actual impedance value of a speaker at all!

CoolJazz

TECHNOKID

CoolJazz wrote: »

...and to clarify for the record, as established before, using a voltmeter does not tell you the actual impedance value of a speaker at all!

CoolJazz

Using a multimeter or ohmeter (not voltmeter) will give you the static/DC impedance of the speaker(s) (read the impedance/resistance of the coil) and this is exactly what is shown in the speaker's specs/user manual. Yes, the dynamic impedance is a different ball game but the static/nominal impedance is always the reference when talking about impedance matching. OK, I went back and I did mention a multimeter (NOT VOLTMETER) which measures resistance and impedance). Multimeter = measures r

vc69

TECHNOKID wrote: »

For people who do not understand ... <snip>

Cheers!

Good grief.

The load (impedance) presented by a single speaker does not represent the load presented by a typical home speaker with a crossover network and more than one driver (woofer, mid, tweeter).
also
The impedance of *any* speaker varies according to the frequency(s) and amplitude of the signal being reproduced.

Hence CoolJazz's statement.

Krazyz1

LOTS of good info. I will take some variables out and be more specific. I have Polk RTiA9's with jumper bars removed. They are bi-wired and sound " meatier " , more substance. I like the sound improvement. I just didn't know if the amp would now think it is hooked up to a 4 ohm speaker instead of a 8 ohm. Hope I clairified a little more understandable the concern.

Systems

vc69 wrote: »

The impedance of *any* speaker varies according to the frequency(s)

True that,it is not a pure resitance.

F1nut

Krazyz1 wrote: »

LOTS of good info. I will take some variables out and be more specific. I have Polk RTiA9's with jumper bars removed. They are bi-wired and sound " meatier " , more substance. I like the sound improvement. I just didn't know if the amp would now think it is hooked up to a 4 ohm speaker instead of a 8 ohm. Hope I clairified a little more understandable the concern.

If you replaced the jumpers with high quality wire, you would get the same result.

Your amp is still seeing a nominal 8 ohm load.

Krazyz1

Thanks for the concrete answer

sTiLlLeArNiNg

F1nut wrote: »

If you replaced the jumpers with high quality wire, you would get the same result.

I don't think it need's to be "high quality" i think pretty much any speaker wire is better than the stock jumper plate's

dorokusai

The plates just stink....jumpers are cheap and easy to make.

WilliamM2

If that the case, the traces on the crossover circuit board must really stink. And what about the plain metal tabs on the drivers?

F1nut

William....please stifle.

dorokusai

WilliamM2 wrote: »

If that the case, the traces on the crossover circuit board must really stink. And what about the plain metal tabs on the drivers?

I agree.

sTiLlLeArNiNg

Trace's on the circuit board should be best grade copper, speaker terminal's ARE questionable. If you like your stock jumper bar's use 'em I bet ya if ya peel 'em off and use some speaker wire you would hear a difference too

Toolfan66

I replaced my stock jumpers on my 1.2's and it made a world of difference.

Has anybody ever got inside the cabenets and just wired everything to the bottom post's?