"Bi-Wiring" Your Powered Towers: The Definitive Reference
Aaron
Posts: 1,853
Fact:
If a speaker can be bi-wired, it can also, by definition, be bi-amped. Since the Polk powered towers cannot be bi-amped, they therefore cannot be bi-wired either.
The Confusion
Polk's powered towers have two sets of binding posts which would seem to indicate that they can be bi-wired and bi-amped. However, this is not the case. The top set of binding posts feeds the midrange and tweeter while the lower set of binding posts feeds the speaker-level input of the built-in subwoofer amplifier.
Hook-Up Methods
1. speaker-level connection to either set of terminals with the binding post jumper in place
2. speaker-level connection to the top set of terminals with a line-level connection (RCA) from the "sub out" of the receiver/preamp to the sub in on the speakers
3. speaker-level connection to the top set of terminals with a line-level connection (RCA) from the left and right channel preouts of the receiver/preamp to the sub in on the speakers
The "Bi-Wire" Hook-Up Method
This is a variation of hook-up method 1 from above and is connected in the same way that you would bi-wire a speaker such as the RTi70. Two sets of speaker wires are run from the same set of terminals on the receiver/amp to the two separate sets of terminals on the speaker with the jumper plate removed.
While this is not bi-wiring by definition, it does accomplish a similar thing: it separates the midrange and tweeter signal from the subwoofer (bass) signal. This is why there is confusion over the term that is used to describe this hook-up method. I think that a new term needs to be coined for this hook-up method such as "powered tower bi-wiring."
To speculate a bit, I doubt that this hook-up method provides as much benefit as it does on a regular bi-wirable speaker for two reasons:
1. Even when using hook-up method 1, the amount of bass energy present in the speaker wire and crossover should be significantly less than in a passive speaker, because the subwoofer amplifier is only using the signal and then amplifying the driver itself (rather than using your receiver/amp's power to drive the subwoofer). I could be on this point, though.
2. In a passive speaker like the RTi70, the top posts would not see as low of a frequency as the powered towers do. Vice versa, the bottom terminals on the passive speaker would see a higher frequency than the powered tower. For example, the RT1000i crosses over between the midrange and subwoofer at 90Hz. Therefore, the top posts would see 90-20,000Hz. while the bottom posts would see 20-90Hz. In a passive speaker such as the RTi70, I would guess that the bottom posts would see a greater frequency range such as 20-200Hz. What this does is create a greater separation of the signal. More bass energy is removed from the midrange and tweeter signal (top terminals) and put with the bass signal (lower terminals). This should help to clean up the midrange and tweeter signal a bit more.
When you consider this, especially when coupled with point 1 above, it would seem that powered towers do not benefit as much from this hook-up method as do passive speakers. Regardless, this is just my theory, and I have no tested it.
Optimal Hook-up Method
The optimal hook-up method for powered towers is speaker-level connections. Specifically, I feel that there is some additional benefit to the "powered tower bi-wire" hook-up method. I can only see disadvantages to using the line-level connections unless you have a really old Pro-Logic system. I see two problems with line-level connections:
1. It would seem like this method would create some phasing (timing) problems between the midrange/tweeter signal and the subwoofer signal since you're sending them through different signal paths both in the receiver and the speaker. Also, you're likely sending them through different wire lengths as well.
2. This is probably the more important one. If you use line-level connections, the sonic signature (flavor of sound, if you will) will be different, because it has not been influenced (colored) by the amplifier. If speaker-level outputs are used, the signal that the subwoofer amplifier sees is going to have the same sonic signature as the rest of the signal seen by the midrange and tweeter. Still, the subwoofer amplifier will have a different sonic signature than the receiver, but this method will help to minimize the problem.
The only downside I see to speaker level connections for the powered tower subwoofer is that they will not be as clean as line-level signal. This is because the receiver has introduced its distortion/uncleanness into the signal. Overall I still feel this is the optimal hook-up method.
Conclusion
I hope you all found this discertation helpful, informative, and even entertaining.
Aaron
If a speaker can be bi-wired, it can also, by definition, be bi-amped. Since the Polk powered towers cannot be bi-amped, they therefore cannot be bi-wired either.
The Confusion
Polk's powered towers have two sets of binding posts which would seem to indicate that they can be bi-wired and bi-amped. However, this is not the case. The top set of binding posts feeds the midrange and tweeter while the lower set of binding posts feeds the speaker-level input of the built-in subwoofer amplifier.
Hook-Up Methods
1. speaker-level connection to either set of terminals with the binding post jumper in place
2. speaker-level connection to the top set of terminals with a line-level connection (RCA) from the "sub out" of the receiver/preamp to the sub in on the speakers
3. speaker-level connection to the top set of terminals with a line-level connection (RCA) from the left and right channel preouts of the receiver/preamp to the sub in on the speakers
The "Bi-Wire" Hook-Up Method
This is a variation of hook-up method 1 from above and is connected in the same way that you would bi-wire a speaker such as the RTi70. Two sets of speaker wires are run from the same set of terminals on the receiver/amp to the two separate sets of terminals on the speaker with the jumper plate removed.
While this is not bi-wiring by definition, it does accomplish a similar thing: it separates the midrange and tweeter signal from the subwoofer (bass) signal. This is why there is confusion over the term that is used to describe this hook-up method. I think that a new term needs to be coined for this hook-up method such as "powered tower bi-wiring."
To speculate a bit, I doubt that this hook-up method provides as much benefit as it does on a regular bi-wirable speaker for two reasons:
1. Even when using hook-up method 1, the amount of bass energy present in the speaker wire and crossover should be significantly less than in a passive speaker, because the subwoofer amplifier is only using the signal and then amplifying the driver itself (rather than using your receiver/amp's power to drive the subwoofer). I could be on this point, though.
2. In a passive speaker like the RTi70, the top posts would not see as low of a frequency as the powered towers do. Vice versa, the bottom terminals on the passive speaker would see a higher frequency than the powered tower. For example, the RT1000i crosses over between the midrange and subwoofer at 90Hz. Therefore, the top posts would see 90-20,000Hz. while the bottom posts would see 20-90Hz. In a passive speaker such as the RTi70, I would guess that the bottom posts would see a greater frequency range such as 20-200Hz. What this does is create a greater separation of the signal. More bass energy is removed from the midrange and tweeter signal (top terminals) and put with the bass signal (lower terminals). This should help to clean up the midrange and tweeter signal a bit more.
When you consider this, especially when coupled with point 1 above, it would seem that powered towers do not benefit as much from this hook-up method as do passive speakers. Regardless, this is just my theory, and I have no tested it.
Optimal Hook-up Method
The optimal hook-up method for powered towers is speaker-level connections. Specifically, I feel that there is some additional benefit to the "powered tower bi-wire" hook-up method. I can only see disadvantages to using the line-level connections unless you have a really old Pro-Logic system. I see two problems with line-level connections:
1. It would seem like this method would create some phasing (timing) problems between the midrange/tweeter signal and the subwoofer signal since you're sending them through different signal paths both in the receiver and the speaker. Also, you're likely sending them through different wire lengths as well.
2. This is probably the more important one. If you use line-level connections, the sonic signature (flavor of sound, if you will) will be different, because it has not been influenced (colored) by the amplifier. If speaker-level outputs are used, the signal that the subwoofer amplifier sees is going to have the same sonic signature as the rest of the signal seen by the midrange and tweeter. Still, the subwoofer amplifier will have a different sonic signature than the receiver, but this method will help to minimize the problem.
The only downside I see to speaker level connections for the powered tower subwoofer is that they will not be as clean as line-level signal. This is because the receiver has introduced its distortion/uncleanness into the signal. Overall I still feel this is the optimal hook-up method.
Conclusion
I hope you all found this discertation helpful, informative, and even entertaining.
Aaron
Post edited by Aaron on
Comments
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Bravo!Check your lips at the door woman. Shake your hips like battleships. Yeah, all the white girls trip when I sing at Sunday service.
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My RT2000P also agrees
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del44
Sure have hauled a lot of Jack Daniels bottles out of your town....Oh, the bottle has been to me, my closes friend, my worse enemy! -
Good post Aaron,
I se you did some homework on the subject.I really would like to sell you my rt1000p's so you can hear the differences between hookups.It's fun to hear the difference.
You points on the line level are very correct even without hearing it yourself.The line level from left and right preouts did sound poor, the worse out of all the different ways to wire them.
I was shocked(and clear)on what it did.It made sence looking at it from a sonic signature,but from clarity standpoint from the mids and highs,it simply didn't blend it anymore.
To a degree I understand why it does what it does.
I guess for know we can call it MANTIS WIRING untill someone develops a completely Correct Term for wiring powered towers in speaker level,Bi wiring.
Again Good Post,
DanDan
My personal quest is to save to world of bad audio, one thread at a time. -
So can we agree, the rt1000's cannot be bi-wired?
Cheers,
RussCheck your lips at the door woman. Shake your hips like battleships. Yeah, all the white girls trip when I sing at Sunday service. -
Not fully buddy,In my Opnion they still are due to the seperation and better sound quality.All your points are noted and somewhat agreed.Dan
My personal quest is to save to world of bad audio, one thread at a time. -
Any speaker can be bi-wired. Your simply running to sets of wires from a single amp source (1 channel) to a single speaker. Bi-amp is different. Two sets of binding post (usually seperating tweet-mid-bass)with speaker wire coming from two different amp channels. I have the owners manual for the rt1000p's and it says nothing about biamping. CS400 is a bi-ampable speaker. So round and round it goes.;)
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Any speaker? Due to sound seperation and quality?
You guys blow me away, idiot savants, every last one of ya!!!
Cheers,
RussCheck your lips at the door woman. Shake your hips like battleships. Yeah, all the white girls trip when I sing at Sunday service. -
Agreed.You guys blow me away, idiot savants, every last one of ya!!!
Aaron -
Excellent post Aaron.
Peace Out~:DIf...
Ron dislikes a film = go out and buy it.
Ron loves a film = don't even rent. -
ahhhhhhhh......nope.
In order to Biwire or biamp each pair of binding posts MUST correspond to a crossover point. You can either do it with separate wires from the same amp (biwire) single set of wires from two different amps (biamp) OR a single set of wires from one amp to one set of posts with a jumper installed between the posts. To paraphrase Ken Swauger, if there isn't power to one set of binding posts (either biamp,biwire or jumpers) you will get no sound out of that part with no signal flowing in to the crossover.
In the case of the RT1000, the top binding post goes to the tweet and the midbass driver (you can't separate them) and the other is a high level input for the powered sub.
I don't get what is so difficult to understand about this. I'm barely literate and it makes sense to me. Geeze, it's not like we are arguing what sounds better, Carver or Adcom or trying to split the atom. I mean this is pretty straightforward stuff here.
BDTI plan for the future. - F1Nut -
Any speaker can be bi-wired
How would I do this with my 1C's? If this is true....I could bi-amp them also....how can I do this?
Oh, the bottle has been to me, my closes friend, my worse enemy! -
Sorry nascarmann, I should have not said it like that. This is the basic fundamental i looked up.
How Bi-wiring Works
Bi-wiring is accomplished via separate pairs of terminals on the loudspeaker system, typically one pair for the woofer, and one pair for the tweeter or midrange and tweeter. They are completely separated electrically from one another. The normal function of a loudspeaker crossover is to guide the proper frequency's to the proper driver. Lows to the woofer, and highs to the tweeter. This is done in part for protection from the division of labor that has occured with two disparate speakers: tweeters will be damaged or destroyed if exposed to low frequency's and woofers just heat up when exposed to the higher frequency's, as they are too massive to respond at all. The other function that a crossover provides is in allowing the two speakers to blend together, to mesh with one another to become a single apparent sound source. They can also provide some passive EQ of the drive units, as long as there is excess energy to throw away.
http://www.audioasylum.com/audio/cables/messages/4953.html
[URL=http://]http://www.audioasylum.com/audio/cables/messages/4953.html[/URL] -
Simple teminalgy.
What is Bi-Wiring ?
Bi-Wiring is the use of two pairs of cables between each amplifier channel and the associated loudspeaker.
The crossover in a "Bi-Wireable" speaker has two separate earth and or signal paths.
By keeping these paths separate all the way back to the amplifier retrieval of fine detail can be improved.
Simply remove the links connecting both positive and negative binding posts together, and run two identical lengths of cable to each speaker from the amplifier output terminals.
Special "Bi-Wire" cable is available for a tidier installation.
What Is Bi-Amping?
Bi-Amping is similar in principle to Bi-Wiring but uses a separate amplifier for each set of terminals.
This can give even greater benefits than Bi-Wiring as the smearing of the delicate higher frequency information due to masking from the bass information can be significantly reduced. It is important that the amplifiers used are of the same type, or have matched gains.
Speakers that can be "Bi-Wired" can generally be "Bi-Amped" as the crossover is essentially two or more separate circuits isolated from one another (when the links are removed).
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Right, but the point your missing is that on the RT1000, THERE ISN'T A CROSSOVER POINT ASSOCIATED TO THE BOTTOM BINDING POST, I understand the confusion but it just ain't so. It is a high level input to the powered sub portion of the speaker.
I'm whipped man, I can't even think about this anymore. It's time to have a beer.
BDTI plan for the future. - F1Nut -
I can see we are all learning about bi wiring and bi amping.
Lets play nice this time around ok?
No need for name calling.Post what you think bi wiring is and exactly why you can't bi wire some speakers.
Also don't quote other people as why you can't do this.
Everyone that posted now and in the past says powered towers can't be bi wired,yes they can.
Now if you say no they can't explain what running a bi wire to a pair of powered towers is called.
This could be the post to end it.
I'm just gonna hang around and see what happens.
DanDan
My personal quest is to save to world of bad audio, one thread at a time. -
Also, people who have posted previously their complete out and out fabrications of having wives, children, are building brand new homes with subfloors, home theaters, that they have magic elves for line conditioners, and benevolent wizards supplying current for their wood veneered Audience 82's ... please explain why you do it.
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TroyD,
Hey I totally understand the rt1000's are NOT bi-wireable and you are right. That is why there is no bridge between the binding post which will usually indecate a bi-wireable speaker. The simple fact is that each set of binding post HAVE to have a seperate crossover within the speaker. I still believe that the CS400 has this setup. I got itTHERE ISN'T A CROSSOVER POINT ASSOCIATED TO THE BOTTOM BINDING POST
right?;) -
NO man,
the rt1000p's and I's come with a bridge from the factory.You need to remove it in order to use line level to the line level in or run a seperate pair to the lower binging posts.Same as the cs400 center.Dan
My personal quest is to save to world of bad audio, one thread at a time. -
Obviously not or we wouldn't be having this discussion. Re-read my dissertation.I can see we are all learning about bi wiring and bi amping.
Unlike speaker preference, this is not an opinion-based question. There is, in fact, only one correct answer to this question. Re-read my dissertation.Post what you think bi wiring is and exactly why you can't bi wire some speakers.
No they can't. Re-read my dissertation.Everyone that posted now and in the past says powered towers can't be bi wired,yes they can.
Mantis,
I know you're not this retarded. I think you're just being stubborn about the term usage. For some reason you just can't let go of the term "bi-wire." If you honestly think that what you are doing is bi-wiring, then let's see some explanation on your part that can refute what I've stated.
Aaron -
So, following your logic, if I were to remove the jumper and connect speaker wire to the top set of terminals and use the an RCA line-level connection for the sub, that would be bi-wiring? There's separation between the signals! Pfft, yeah right that's bi-wiring!In my Opnion they still are due to the seperation and better sound quality.
Aaron -
I think after all these beers.......I'm going to throw up.....Oh, the bottle has been to me, my closes friend, my worse enemy!
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The metal straps in the rt1000's have nothing to do with bi-anything - they have to do with how you are running the sub. If your are using any type of rca jack to the input for the sub then u take the bridges out. If you are NOT running any type of rca jack to the speakers sub input then u leave the bridge in.the rt1000p's and I's come with a bridge from the factory.You need to remove it in order to use line level to the line level in or run a seperate pair to the lower binging posts.Same as the cs400 center.
The cs400 has nothing to do with that. I have both speakers and manuals. CS400 IS bi-wire and bi-ampable. :cool: -
Look,
Here's my end to this.
I like what I have done to my speakers.I noticed a big sound improvement over all other wire configurations.The "BI WIRE" configuration weather any of you think it's right or not,I LIKE THE WAY IT SOUNDS.
CALL IT ANYTHING YOU WANT!!!!!!
I have had 3 different Bi Wire Cables connected to my speakers and they seem to get the job done.
Monstercable MCX-bi wire
Monstercable M1.4s Bi wire
Monstercable Custom install 14x4 I made myself with Banana ends and shrinkwrap.
To all you powered tower owners,
This is the best way I feel to wire these speakers.I will stop using the term BI WIRE and call it MANTIS WIRING untill someone other then myself gives it a proper term.
When I buy Transparent speaker wires(which I'm waiting to untill I pick out my new speakers and measure the length I need).This topic will be dead to me as I won't own them for much longer,Nor will I ever own powered towers again.
So give it a name and I'll be sadisfied with that.
A straight point..........
Can Polk's powered towers be bi wired physically????
ANSWER.....Yes they can!!!!!
Is this Ture BI WIRING???
ANSWER.....In my opnion yes it is only because of sound improvement,and the fact the wiring is EXACTLY the same.You can use PREMADE BI WIRE cables.
What exactly have you done here?
ANSWER....Wired the mids and highs with THERE OWN RUN of speaker cable,and run the sub in SPEAKER LEVEL.
Have you tried all other possible wiring configurations???
ANSWER...Yes I have.
Can these speaker be bi amped??
Answer...YES THEY CAN.
Do you think this is benificial?
ANSWER...No, as I feel your wasting the 2nd amp.I could go into great detail why I wouldn't bi amp this speaker externally.
In short it allready has a 2nd amp so it is already BI AMPED.Difference being the 2nd amp is built in.
I still don't understand why you can't Bi amp this speaker?
ANSWER...well you can but the only thing i could possibly see in benifit in doing this is to capture the sonic signature from the second external amp.
What do you mean by sonic signature??
ANSWER.....in short the way the output drives a speaker.Dynamic range changes from amp to amp with the same driving line level signal from a given preamp.This is a complete topic that should be researched,then experienced.
You you know exactly how this speaker is internally?
ANSWER...yes there is one crossover in the sealed mid and high section of the cabnet.Only one set of binding posts wired to it.Then there is another crossover for the sub section,a plate amp and one set of binding posts and a line level in to drive the sub section.
How do you know this?
ANSWER...at one point I ordered the newer crossover and tweeter from the rt1000i's as I own the rt1000p's.I felt that the rt1000i's had a better mid and high range balance.So I bought the new crossover and Tweeter and Installed them into my speakers.Instead of buying new speakers,as the rest of the speaker is the same,except the color of the mid range driver,and they took away the velvin sound material from the front then added a bottom grill..I asked Polk about the 6 1/2 midbass driver they told me that the driver is exactly the same except the color of the cone.The 5 1/4 driver was modified from the last year model.
After 50 hours or so I noticed a great deal of sound quality improvement over the older tweeters and crossover.I was happy with the upgrade.
Now look......thats it for the powered thing.
Dan
My personal quest is to save to world of bad audio, one thread at a time. -
I thought about it some more and really it comes down to sound quality.NO matter how you get there it's what is important in the end.
Why would you bi wire any speaker?for the looks?Because you can?Because they said so?
I say NO to all of the above.....it's sound quality man ,no more no less.Dan
My personal quest is to save to world of bad audio, one thread at a time. -
Thank you ladies and gentlemen, this logic-free post has been brought to you by......Check your lips at the door woman. Shake your hips like battleships. Yeah, all the white girls trip when I sing at Sunday service.
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Nothing's changed since I've been gone, huh....
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should we start a Pole on this just to quantify the opinions?
I would suggest a 2 part yes or no answer to the questions:
Can Power Towers be Bi-Wired? "No additional amp just 4 wires"
Can Power Towers be Bi-Amped? "4 wires and 2 amps."
This will remove any confusion regarding the interpretation of the definition regarding Bi-Wire.
Who wants to take the leed?***WAREMTAE*** -
Not me, I say let the short-bus ****'s use their terminology, and the rest of us will have the 'right' terminology.
Cheers,
RussCheck your lips at the door woman. Shake your hips like battleships. Yeah, all the white girls trip when I sing at Sunday service.
