Bi amping?????? Help

tonyb

WilliamM2 wrote: »

So you think that amps store power? And that large tower speakers are harder to drive than small bookshelf speakers? Any other misconceptions of his you agree with?

Speaker design has more to do with how hard they are to drive, but generally speaking, the more drivers a speaker has, the more current it will need to move those drivers in and out, and even more importantly, stop on a dime. How do you think you get flabby bass ?

If you don't think an amp stores power, then please kindly inform the rest of us what it does....exactly.

Tankman- I appreciate your thoughts, but I'm nowhere near F1nuts level, plus he has better hair than I do.

rebuy

tonyb wrote: »

Last thing I ever claim to be is a know it all.

The 2 sets of posts represent the lows and the high end of the speaker build. The straps connect the 2 sets of posts. Those straps are made of cheap brass so if you think the signal is better humming along brass,than copper, cool, run with it, but you'd be in the minority with that. Both sets of posts are connected to the crossover, you can't run with just one set of post for the speaker to work without the straps connecting them, or 2 sets of wire going to all 4 posts. More benefits obviously when bi-amping, but even then the purist in this hobby will say you have to have an external crossover. The 4 posts are there for bi-wire,bi-amping, nothing more,nothing less. Bi-wiring eliminates that brass jumper, and most just use regular good quality speaker wire to replace it. Some feel that sending a signal, uninterupted to each set of post garners some benefit over sending the signal to one set of posts, along a brass jumper or speaker wire, to another set of posts. It's about keeping the signal as direct as possible.

Now wether that whole shabang is audible or not is up for discussion. Some say yep, some say nay, guess it all depends on your ear, and the gear involved.

BTW- I don't need a thinking cap, my tinfoil one works very well. But....if you have a Carmel, California hat laying around, I'd be happy to take it off your hands.

Isn't this what I've said from the beginning?

Tankman

WilliamM2 wrote: »

So you think that amps store power? And that large tower speakers are harder to drive than small bookshelf speakers? Any other misconceptions of his you agree with?

...misconceptions?.No not really.But i do fully agree with both F1nut and Tonyb.As for a Tower being harder to drive then a bookshelf speaker?The more driver's you have in any speaker design a (AMP) with greater output will control the drives from (fluttering).An amp or AVR that has say 120 watts with say 45 high current (overhead) will drive just about any speaker.But most AVR's have only two Ufs in them at the most 15,000Ufs to 18,000Ufs that would be 30,000 to 36,000 total.And a separate amp will have 90,000 to way over 160,000 Ufs in them.Now which amp do you think will drive a Tower or bookshelf better?.The one with just two ufs?or the one with 12 ufs rated at 10,000ufs each?And of course the amp with more ufs in them also has more outputs per channel.

Tankman

tonyb wrote: »

Speaker design has more to do with how hard they are to drive, but generally speaking, the more drivers a speaker has, the more current it will need to move those drivers in and out, and even more importantly, stop on a dime. How do you think you get flabby bass ?

If you don't think an amp stores power, then please kindly inform the rest of us what it does....exactly.

Tankman- I appreciate your thoughts, but I'm nowhere near F1nuts level, plus he has better hair than I do.

..Was just trying to help out.I am no way an expert on this subject,but i do know the basics on this.And yes i agree,i am nowhere near F1nut level either.

tonyb

rebuy wrote: »

Isn't this what I've said from the beginning?

No, because they are not the same, they both achieve one thing though, getting a signal to all 4 posts, just in a different way. There's a million ways to get sound out of speakers too, doesn't mean they are all the same, though they all do the same thing in the end.


Tankman- Glad to see you reading up, gaining some knowlege along the way. Having a basic understanding of how things work, especially how they work together, will go along way in this hobby. Kudo's to you.

PrazVT

F1nut wrote: »

Bi-amping requires each amp to have its own power supply. Your AVR shares one power supply between all the channels. Therefore, it's not capable of bi-amping.

What if you're using a multichannel (say 7ch amp) and devoting 2 channels to the left speaker and 2 channels to the right speaker? Same conclusion?

Been wondering about this for a while. Was bi-amping like this the last few months - but I just switched back to a single channel and single cable run and haven't really heard any drop in SQ.

FTGV

PrazVT wrote: »

What if you're using a multichannel (say 7ch amp) and devoting 2 channels to the left speaker and 2 channels to the right speaker?

That by definition is called "passive bi amping" since each of the hi and low pass sections of the speaker are driven from a different amplifier stage..

- but I just switched back to a single channel and single cable run and haven't really heard any drop in SQ.

That's not surprising since with passive bi amping the passive crossover components are still in the signal path.As with bi wiring I have never found this approach to result in any significant gain in sound quality.

F1nut

PrazVT wrote: »

What if you're using a multichannel (say 7ch amp) and devoting 2 channels to the left speaker and 2 channels to the right speaker? Same conclusion?

Yes.

I see Fred calls it passive bi-amping, but I think even that is giving it too much credit as those channels are still sharing the same power supply. I'd call it ghetto bi-amping.

PrazVT

I'd call it ghetto bi-amping.

ghetto. Got it! Thanks

FTGV

F1nut wrote: »

I'd call it ghetto bi-amping.

Good one Jesse but I think it suitable for a different reason.Regardless if 4 mono bloc's or a multi ch amp is used the full benifits of bi amping won't be realized.

F1nut

Agreed

Tankman

http://forums.soundandvisionmag.com/showthread.php?387660-Bi-Wire-Bi-Amp-Active-Crossovers-OH-MY!!!!For those who need too know.

Jnienke

This is my first post so I am new here. Also, I am new to a Pioneer VSX1021 K with TSi400 front speakers. Currently, I have the metal binding staps removed on each speaker, one set of wires to each speaker going from the left/right receiver outputs to the upper posts of the speakers. The other set of wires from the receiver outputs for the left/right zone 2 connect to the lower speaker posts.

Now, I am not trying to debate the bi-amp issue, rather I am tying to figure out how to determe if the lower posts are for the low frequencies or the high frequencies. The receiver is set-up to biamp the front speakers so does that mean the lwoer frequencies and upper frequencies are seperately supplied from the reciever? If so, which pair of outputs from the reciever should go to which posts on the speakers to avoid sending low frequencies to the tweeter of vise versa? Does any of this make sense and can anyone help me understand????

Thanks,

Jnienke

tonyb

The bottom post are for the low end of the speaker and the top posts for the tweets and mids, basically. You sure in bi-amp mode your suppose to use zone 2 ? Normally it's a back surround channel, could be wrong though. Anyway, I doubt your doing yourself any favors bi-amping with that receiver. Just my .02

Jnienke

tonyb wrote: »

The bottom post are for the low end of the speaker and the top posts for the tweets and mids, basically. You sure in bi-amp mode your suppose to use zone 2 ? Normally it's a back surround channel, could be wrong though. Anyway, I doubt your doing yourself any favors bi-amping with that receiver. Just my .02

tonyb,

Thanks for the reply. I am just going by the wiring diagram in the manual of the receiver. It shows using zone 2 for the bi-amp. You may be correct about my results, I just did not want to damage the speakers. Now, I don't know what frequencies are output on what chanels from this reciever. Pioneer does not seem to provide that bit of information. Anyone happen to know?

Thanks,

Jnienke

tonyb

Most manufacturers claim a full signal, true or not, they are all vague on it. Best to just fire off an email to Pioneer or call to find out.

FTGV

Jnienke wrote: »

The receiver is set-up to biamp the front speakers so does that mean the lwoer frequencies and upper frequencies are seperately supplied from the reciever?

No the speakers passive crossover will still be doing the frequency dividing .With the exception of having certain outputs set for "small "speakers (thus rolling off the low bass)the signal output from all binding posts will be the same.

FTGV

FTGV wrote: »

No the speakers passive crossover will still be doing the frequency dividing .With the exception of having the front L/R outputs set for "small "speakers (thus rolling off the low bass)the frequency range output from all binding posts will be the same.

Clarified.

Tankman

Tankman wrote: »

http://forums.soundandvisionmag.com/showthread.php?387660-Bi-Wire-Bi-Amp-Active-Crossovers-OH-MY!!!!For those who need too know.

...The link is for Bi-amping and so on.With photos of how its done.I found this link and it goes into it.But not too take sides but F1nut is right about true Bi-amping a speaker.You must remove the crossover in the speakers and use an EQ set-up,which would be #1. a Pre/Pro,AVR with Pre-amp outs EQ,Amp then to your speakers.So any other way is well like F1nut has been telling everyone "ghetto" bi-wiring speakers.

FTGV

Tankman wrote: »

..you must remove the crossover in the speakers and use an EQ set-up,.

Actually its an active crossover like this thats needed not an EQ.http://www.marchandelec.com/xm44.html


Here is another good overview of active vs passive http://sound.westhost.com/biamp-vs-passive.htm


And long since out of production heres an example of a very good fully active speaker. http://www.audiophilia.com/hardware/waveform.htm and a current popular DIY active design http://www.linkwitzlab.com/Orion-TSS-review.pdf

Tankman

FTGV, Yep my bad on the EQ thing.Just trying to help clear some of this up.Thank for the links.I don't think i would do that with speakers.Some people say yeah its good some say no.I say if you have a nice crossover in a nice speaker set-up then why do it in the first place?..Just me saying.:cool:

FTGV

Tankman wrote: »

I don't think i would do that with speakers.Some people say yeah its good some say no.I say if you have a nice crossover in a nice speaker set-up then why do it in the first place?..Just me saying.:cool:

Converting a speaker to active operation is far more involved then just removing the passive components and adding the necessary electronics.In fact without the aid of accurate frequency response measurements and perhaps simulation software,in other words some engineering is involved if the results are to be an improvement over the passive version,if not actually inferior.

Tankman

FTGV,again thanks for the links and helping me too understand about this subject.I went back and read what was in the links you posted.Which by the way are more endetailed and a much better link.I see and now unerstand a lot more about this.Again thanks for your time on this.Don't know about anyone else but it cleared up a lot for me.:cool:

FTGV

Your welcome.

Teseract

So my front sound stage is two RTI12's and a CSI5. I have an Onkyo NR708 receiver (110w/channel, rated at 2 channels driven). I have an Adcom GFA-5500. I'd like to get another 3 channel amp with similar ratings (200w/channel). I have a 7.1 system. The rear surrounds are some ~7 year old Sony bookshelf speakers and the surrounds are some Sony towers I modified with a proper but cheap 3 way crossover and a better tweeter/midrange, but the crossover is only rated to 100w. I plan on eventually getting either some RTI8's from Polk on ebay or RTI A7's for the rear surrounds and some RTI A3's for the rears but this is not a near-future type thing.

So what would I be better off doing? Use the Adcom to run the RTI12's normally (I like the damping factor on the GFA-5500 to run the woofers) then use 2 channels of the 3 channel amp to run the surrounds and of course the center channel, then let the receiver just run the rear surrounds?

Or should I use the receiver to passively biamp the RTI12's top section and let the Adcom just run the woofers? I think this might work well as the rear surrounds don't get used that much and with 4 channels driven the receiver probably still outputs 90w/channel.

Or should I use 2 of the channels on the 3 channel amp with the Adcom to passively biamp the RTI-12s? I'm wondering if 200W of power would be too much for the mids/tweeters though.

Just looking for input... thanks!

F1nut

So what would I be better off doing?

Sell the Adcom, buy a 3 channel amp to run the L/C/R, forget bi anything, replace the mismatched speakers.

(I like the damping factor on the GFA-5500 to run the woofers)

A common misconception. The difference between a damping factor of 10 and 1000 is insignificant.

Teseract

A option outside the box, thanks. I'd consider it but the Adcom is sitting on my Dad's workbench with all the magic smoke released from the left channel.

F1nut wrote: »

Sell the Adcom, buy a 3 channel amp to run the L/C/R, forget bi anything, replace the mismatched speakers.

A common misconception. The difference between a damping factor of 10 and 1000 is insignificant.

F1nut

In that case......tie a line to the Adcom, makes a good boat anchor, buy a 3 channel amp to run the L/C/R, forget bi anything, replace the mismatched speakers.

swizzchard

So from this I take it that if using a HT AVR, passive bi-amping nets little to no gain even though the HT AVR and HQ Floor speakers have the capability?

tonyb

swizzchard wrote: »

So from this I take it that if using a HT AVR, passive bi-amping nets little to no gain even though the HT AVR and HQ Floor speakers have the capability?

In theory an avr has the capability, but in reality, not so much. It still uses the same power supply in the receiver which at best is fairly weak when using 7 channels. Mind you, not all AVR'S are as weak as I claim, but a good majority in the sub 1500 buck market.