Taperssection.com

Gear / Technical Help => Playback Forum => Topic started by: SClassical on November 12, 2007, 10:23:21 PM

Title: connecting speakers to amp
Post by: SClassical on November 12, 2007, 10:23:21 PM
Does anyone know what is the difference in sound quality when speakers are connected in a regular way and in a bi-wire way (http://www.davidmannaudio.com/faq/faq3.html)?

Also are these cables made for bi-wiring?

http://www.cs1.net/img/Canare_4S11_4m_HDS5_bi-wire_right_600.jpg

Most people here wire their system in a bi-wire way?
Title: Re: connecting speakers to amp
Post by: boojum on November 13, 2007, 12:21:53 AM
My opinion is that bi-wiring is another hoax to charm those bucks out of your wallet.  Show me a real test which proves otherwise and I will recant.  Not a test where folks know what they are listening to.  A test where neither the tester nor the subject is aware if the bi-amp or regular setup is being used.  Funny how the mfrs never want to run those tests.  LOL

I have been screwing around with audio for ~50 years, have some very nice high-end gear, and none of it requires bi-amping.  I can bi-amp an set of old AR2ax's I have, after I go out and get another pair of hafler DH500's and have them mono-bridged.  Not in this life.

Cheers


Ooops, I had this confused with bi-amping.  I apologize.  Look at the wiring and the same signal is being fed to the separate speaker drivers.  Hmmm.  More snake oil.  Again, show me a reliable and vald test and I will happily recant and rewire my AR's.
Title: Re: connecting speakers to amp
Post by: Frank in JC on November 13, 2007, 08:18:46 AM
My opinion is that bi-wiring is another hoax to charm those bucks out of your wallet. 

Loudspeaker manufacturers don't care how much we spend on cables.  They're the ones who decided their device should be bi-wired, but they don't sell cables do they?

When bi-wiring, the conductor serving the midrange driver is carrying far less current than the conductor serving the woofer.  The difference is at least an order of magnitude, maybe a couple.  Is the signal affected differently in either case?  Many people say yes, but some people say no.  You just have to listen for yourself.
Title: Re: connecting speakers to amp
Post by: Gutbucket on November 13, 2007, 04:47:37 PM
My opinion is that bi-wiring is another hoax to charm those bucks out of your wallet. 

Loudspeaker manufacturers don't care how much we spend on cables.  They're the ones who decided their device should be bi-wired, but they don't sell cables do they?

Well, speaker manufacturer's customers are the ones who really make the decision for them.  If you customer demographic wants to bi-wire, even just perceives the capability of bi-wiring as 'cool' or 'high-tech' even if they never use it, then a speaker manufacturer would be making a bad business decision to not put an extra set of input jacks on the back, regardless of the technical or auditory merits.

Quote
When bi-wiring, the conductor serving the mid-range driver is carrying far less current than the conductor serving the woofer.  The difference is at least an order of magnitude, maybe a couple.  Is the signal affected differently in either case?  Many people say yes, but some people say no.  You just have to listen for yourself.


Bi-wiring comes in two flavors:

A) Bi-wire can be a second set of speaker wires running from the same amp to the same input jacks on the speaker.  You could quintipla-wire if you wanted to.. and yes the current carried in each wire is cut in half each time you double the wires, but do you really think the sound is being limited by the ultimate current carrying ability of your first set of decent gauge speaker cables?

B) Bi-wire can also be a second set of speaker wires running from the same amp to a second set of input jacks that would normally be bridged to the first set (take out the bridge and wire to both input jacks).  That just moves the bridge point back to the amplifier output jacks, and is typically not why the manufacturer puts a pair of bridged inputs on speakers (other than for marketing purposes) ;)

Both of the above just add more wire.



Bi-amping comes in two flavors too:

C) Similar to B) above, Bi-amping uses two sets of speaker wires running to two sets of input jacks on each speaker that would otherwise be bridged (take out the bridge and wire one set of cables to each input jack pair).  But now each set of wires goes to it's own amp.  This just allows more amp power  since you are now using two amp channels per speaker instead of one.  Real world effect? You could run a different amp for the bass that the top end if you wanted, assuming both amps have the same gain.  Also, if you were to clip the amp running the woofers, your tweeters would not be affected.  Each amp is still amplifying the full frequency range and the speaker is still doing the crossover duties.  There might be a slightly easier impedance load seen by each amp, or there might not, but them's details.

D) The speakers are modified to entirely remove or bypass the crossover (or a significant portion of it). This eliminates most components between the amp and the driver. An active crossover stage is added before the amplifiers to split the frequency range before amplification.  Each amplifier then amplifies only the frequency range needed for the driver(s) it feeds.  Most importantly, the load seen by the amplifier is definitely less complex and much easier to drive since the frequency spitting and driver balancing is done on line level signals and not speaker level signals, so you can use much smaller amplifiers to do the same job.  This works well and it's how huge PA systems are designed and how better 'active' monitors work where the active x-overs, amps, speaker cables and drivers are all in the same box.  But it's rather complicated to implement properly with a standard speaker.  You need test equipment to really setup the crossover correctly and it's WAY easy to fry things if done wrong.. which is why you won't find this option common with speaker manufacturers unless they are doing all of it themselves 'in the box' of an active monitor.

Those are the facts.. and here's a (widely held) opinion:

Speaker manufacturer's are probably thinking about C) above. It's relatively simple and foolproof to implement, might actually make some real improvements at times and satisfies the tweaky audiophile crowd.  If customers want to do B) that's fine with the manufacturer, even if it just adds wire.  If they want to do D), where the real gains are to be seen, they're on their own (to hell with the warranty).
Title: Re: connecting speakers to amp
Post by: bobbygeeWOW on November 13, 2007, 10:42:53 PM
So uh, here's what I'm doing (for a laugh) right now:

Certified CAT-6 ethernet cable for speaker wire, seperate cable for positive and negative on each speaker.

So that's four solid-core independant twisted pairs per connection, precisely spaced with the little plastic thingy.
What's weird is that some pairs are wound more tightly than others - resulting in some conductors being shorter than the others!
Diggin' the sound though :) 
Title: Re: connecting speakers to amp
Post by: Tim on November 13, 2007, 10:44:33 PM
I know CAT-5 is used for speaker cable
Title: Re: connecting speakers to amp
Post by: bobbygeeWOW on November 13, 2007, 10:54:35 PM
Yeah, CAT-5 is commonly used for installations, with pos/neg in the same cable - the twisted pairs causing them to gain some independance from each other.
I used CAT-6 on a lark cause it was sitting around, decided to run seperate pos/neg cables, then realized the different twists would effectively result in different lenths within the same conductor  ::)  So far so good tho!
Title: Re: connecting speakers to amp
Post by: Frank in JC on November 14, 2007, 08:13:58 AM

A) Bi-wire can be a second set of speaker wires running from the same amp to the same input jacks on the speaker.  You could quintipla-wire if you wanted to.. and yes the current carried in each wire is cut in half each time you double the wires, but do you really think the sound is being limited by the ultimate current carrying ability of your first set of decent gauge speaker cables?

B) Bi-wire can also be a second set of speaker wires running from the same amp to a second set of input jacks that would normally be bridged to the first set (take out the bridge and wire to both input jacks).  That just moves the bridge point back to the amplifier output jacks, and is typically not why the manufacturer puts a pair of bridged inputs on speakers (other than for marketing purposes) ;)

Both of the above just add more wire.


(A) is not a practical example of "bi-wiring" for the end-user, but some manufacturers (Jena Labs for example) do parallel their conductors.

(B) You are mistaken.  While that indeed is an example bi-wiring, it does more than "move the bridge point back to the amplifier output jacks."  The current level in the cables powering the midrange driver and tweeter is much lower than in the cables powering the woofer.  (Why?  Because their frequency/impedance characteristics are wildly different.)  The same signal is present in both conductors, but outside the bandpass of each module's crossover, the impedance approaches infinity.  If you just use a bridge at the loudspeaker, the composite load of both modules is "seen" on the same set of cables.  This, and bi-amping, is exactly why manufacturers provide two sets of inputs.



Title: Re: connecting speakers to amp
Post by: Gutbucket on November 14, 2007, 11:26:02 AM

A) Bi-wire can be a second set of speaker wires running from the same amp to the same input jacks on the speaker.  You could quintipla-wire if you wanted to.. and yes the current carried in each wire is cut in half each time you double the wires, but do you really think the sound is being limited by the ultimate current carrying ability of your first set of decent gauge speaker cables?

B) Bi-wire can also be a second set of speaker wires running from the same amp to a second set of input jacks that would normally be bridged to the first set (take out the bridge and wire to both input jacks).  That just moves the bridge point back to the amplifier output jacks, and is typically not why the manufacturer puts a pair of bridged inputs on speakers (other than for marketing purposes) ;)

Both of the above just add more wire.


(A) is not a practical example of "bi-wiring" for the end-user, but some manufacturers (Jena Labs for example) do parallel their conductors.

Not practical? why not, just add a second set of wires.. totally practical, just not very effective.

Quote
(B) You are mistaken.  While that indeed is an example bi-wiring, it does more than "move the bridge point back to the amplifier output jacks."  The current level in the cables powering the midrange driver and tweeter is much lower than in the cables powering the woofer.  (Why?  Because their frequency/impedance characteristics are wildly different.)  The same signal is present in both conductors, but outside the bandpass of each module's crossover, the impedance approaches infinity.  If you just use a bridge at the loudspeaker, the composite load of both modules is "seen" on the same set of cables.  This, and bi-amping, is exactly why manufacturers provide two sets of inputs.

Yes your are correct. My biases are showing.  I still think it's pretty useless.  IMO the frequency/impedance characteristics you mention do have an effect on the amplifier driving the load depending on it's design, which is why bi-amping like in example C) has merit, but on just the cables? Eh.
Title: Re: connecting speakers to amp
Post by: Nick's Picks on November 15, 2007, 07:42:43 AM
when I went from a single cable to a double cable setup to my Von Schweikert VR4s, the difference was not insignificant.  It was like a switch in the whoofer was turned "on" for the first time.
Title: Re: connecting speakers to amp
Post by: tiberiusbkirk on November 15, 2007, 10:13:36 AM
I'd figure the speaker maker designed it to be bi wired, so what the hey.
that said, using a vintage receiver I'm back to using plain old 16 gauge copper wire
and I hear no difference. I'm using a short cable for the bi wire connection instead
of the copper bar.
I think it's because my Tandberg receiver sounds oh so sweet.
Title: Re: connecting speakers to amp
Post by: Gutbucket on November 15, 2007, 10:38:15 AM
when I went from a single cable to a double cable setup to my Von Schweikert VR4s, the difference was not insignificant.  It was like a switch in the whoofer was turned "on" for the first time.

Mmmm, shoe leather..

Interesting to hear it made a difference to you Nick. It hasn't made any real difference in my experience and I rationalize that with the explanation above.  Maybe there is more to it than I give credit for, but it would definitely be 'system dependant'.  I've tried it on several different speaker/amp combos without detectable effect, but I'll keep my mind and ears open.

[/removing foot from mouth]
Title: Re: connecting speakers to amp
Post by: Nick's Picks on November 15, 2007, 02:15:44 PM
my dealer was telling me to do this..."Nick, you can't run the VR4s any other way, you'll see", he would say.
he was right.
Title: Re: connecting speakers to amp
Post by: carlbeck on November 16, 2007, 07:08:50 AM
I am not touching this one with a 10 foot pole!
Title: Re: connecting speakers to amp
Post by: L Ron Hoover on November 17, 2007, 11:14:13 AM
I am not touching this one with a 10 foot pole!


C'mon Carl touch it.
Title: Re: connecting speakers to amp
Post by: carlbeck on November 17, 2007, 03:04:23 PM
Nope I don't have enough piss in me for this pissing match  ;D

Maybe once I come up with a "scientific test" to explain emotions then possibly I may be able to keep up with all the so called experts around these parts lately
Title: Re: connecting speakers to amp
Post by: Lil Kim Jong-Il on November 17, 2007, 06:38:53 PM
then possibly I may be able to keep up with all the so called experts around these parts lately

keep dreaming.