[vMike]

I am thinking of bi amping my speakers using the extra 2 amps on my 7.1
avr. Using the small v. large settings and adjusting the crossover, I can
adjust the active crossover for the smalls to 350hz (matching the speakers
crossover) so that the mids and tweeters primarily get upper frequencies.
I do not have the ability to adjust the high pass crossover for the larges
so the woofers will get the full range of frequencies which will then use
the speaker's passive crossover.

Is this limitation going to negate the benefits of biamping?

mike

[Don Pearce[_2_]]

On Thu, 22 Jan 2009 16:29:39 -0500, "vMike"
wrote:

I am thinking of bi amping my speakers using the extra 2 amps on my 7.1
avr. Using the small v. large settings and adjusting the crossover, I can
adjust the active crossover for the smalls to 350hz (matching the speakers
crossover) so that the mids and tweeters primarily get upper frequencies.
I do not have the ability to adjust the high pass crossover for the larges
so the woofers will get the full range of frequencies which will then use
the speaker's passive crossover.

Is this limitation going to negate the benefits of biamping?

mike




There are no benefits to biamping. Anything you may have been told to
the contrary is wrong. There are, however, plenty of things that can
go seriously bad when you biamp, from poor high/low matching to an
unexpected blast of mains hum destroying a tweeter.

d

[Kalman Rubinson[_3_]]

On Thu, 22 Jan 2009 16:29:39 -0500, "vMike"
wrote:

I am thinking of bi amping my speakers using the extra 2 amps on my 7.1
avr. Using the small v. large settings and adjusting the crossover, I can
adjust the active crossover for the smalls to 350hz (matching the speakers
crossover) so that the mids and tweeters primarily get upper frequencies.
I do not have the ability to adjust the high pass crossover for the larges
so the woofers will get the full range of frequencies which will then use
the speaker's passive crossover.

Is this limitation going to negate the benefits of biamping?

mike


I do not know what AVR you have but, typically, most do not offer any
crossover for biamping at all and the crossover you see in "small" is
for crossing over to the subwoofer(s). They generally output full
bandwidth signals over both amps and let the built-in crossover in the
speaker handle the distribution.

Thus, if you use this setting with a 350Hz crossover, the HF part of
your biamped speakers will get 350Hz and up, the LF part of your
biamped speakers will also get 350Hz and up and your sub(s) will get
350Hz and down. Not a good idea.

Kal

[vMike]

"Kalman Rubinson" wrote in message
...
On Thu, 22 Jan 2009 16:29:39 -0500, "vMike"
wrote:

I am thinking of bi amping my speakers using the extra 2 amps on my 7.1
avr. Using the small v. large settings and adjusting the crossover, I can
adjust the active crossover for the smalls to 350hz (matching the speakers
crossover) so that the mids and tweeters primarily get upper frequencies.
I do not have the ability to adjust the high pass crossover for the larges
so the woofers will get the full range of frequencies which will then use
the speaker's passive crossover.

Is this limitation going to negate the benefits of biamping?

mike


I do not know what AVR you have but, typically, most do not offer any
crossover for biamping at all and the crossover you see in "small" is
for crossing over to the subwoofer(s). They generally output full
bandwidth signals over both amps and let the built-in crossover in the
speaker handle the distribution.

Thus, if you use this setting with a 350Hz crossover, the HF part of
your biamped speakers will get 350Hz and up, the LF part of your
biamped speakers will also get 350Hz and up and your sub(s) will get
350Hz and down. Not a good idea.

Kal

Kal,
Thanks for the information. I currently have my sub disconnected and was
not planning to use it as my new speakers have plenty of bass. Also, my sub
has it's own amp and active crossover setting. The amp manual says the
crossover sets the frequency at which bass tones are removed from the small
main speakers and sent to the subwoofer line out. It further states that if
the speakers are set to large the entire frequency range is sent to the
speakers and the crossover is ignored whether I have a sub or not. Does
that change anything?

Mike

[jakdedert]

vMike wrote:
"Kalman Rubinson" wrote in message
...
On Thu, 22 Jan 2009 16:29:39 -0500, "vMike"
wrote:

I am thinking of bi amping my speakers using the extra 2 amps on my 7.1
avr. Using the small v. large settings and adjusting the crossover, I can
adjust the active crossover for the smalls to 350hz (matching the speakers
crossover) so that the mids and tweeters primarily get upper frequencies.
I do not have the ability to adjust the high pass crossover for the larges
so the woofers will get the full range of frequencies which will then use
the speaker's passive crossover.

Is this limitation going to negate the benefits of biamping?

mike

I do not know what AVR you have but, typically, most do not offer any
crossover for biamping at all and the crossover you see in "small" is
for crossing over to the subwoofer(s). They generally output full
bandwidth signals over both amps and let the built-in crossover in the
speaker handle the distribution.

Thus, if you use this setting with a 350Hz crossover, the HF part of
your biamped speakers will get 350Hz and up, the LF part of your
biamped speakers will also get 350Hz and up and your sub(s) will get
350Hz and down. Not a good idea.

Kal

Kal,
Thanks for the information. I currently have my sub disconnected and was
not planning to use it as my new speakers have plenty of bass. Also, my sub
has it's own amp and active crossover setting. The amp manual says the
crossover sets the frequency at which bass tones are removed from the small
main speakers and sent to the subwoofer line out. It further states that if
the speakers are set to large the entire frequency range is sent to the
speakers and the crossover is ignored whether I have a sub or not. Does
that change anything?

Mike



It sounds like a kludge, but maybe possible. The sub amps would
normally need to be larger than the the hi/mid amps. Disconnecting the
woofers from the passive crossover is also probably going to do some
funny things to the response. It would depend on the design of the
crossover just what that effect might be. It could be that it just
lowers or raises the low/mid cutoff, or it could toast components in the
x-over.

I don't think I'd try it. If you wanted to do it right, I'd think you'd
need to use a dedicated 2-way xover for the hi/mid pair--instead of just
disconnecting the low output of the 3-way--and roughly double the power
on the lows compared to the hi/mids.

If it were me, I'd just use the system as designed, with the active sub
crossed over way low...like 60 Hz or so. That's where many boxes begin
to drop off. If yours don't, and it's possible to go lower on the sub
x-over (most don't), then do it.

Play with it, work with the sub x-over frequency, level, phase, and
placement. You might like what you hear...or not.

jak

[Kalman Rubinson[_3_]]

On Thu, 22 Jan 2009 17:27:48 -0500, "vMike"
wrote:


"Kalman Rubinson" wrote in message
.. .
On Thu, 22 Jan 2009 16:29:39 -0500, "vMike"
wrote:

I am thinking of bi amping my speakers using the extra 2 amps on my 7.1
avr. Using the small v. large settings and adjusting the crossover, I can
adjust the active crossover for the smalls to 350hz (matching the speakers
crossover) so that the mids and tweeters primarily get upper frequencies.
I do not have the ability to adjust the high pass crossover for the larges
so the woofers will get the full range of frequencies which will then use
the speaker's passive crossover.

Is this limitation going to negate the benefits of biamping?

mike


I do not know what AVR you have but, typically, most do not offer any
crossover for biamping at all and the crossover you see in "small" is
for crossing over to the subwoofer(s). They generally output full
bandwidth signals over both amps and let the built-in crossover in the
speaker handle the distribution.

Thus, if you use this setting with a 350Hz crossover, the HF part of
your biamped speakers will get 350Hz and up, the LF part of your
biamped speakers will also get 350Hz and up and your sub(s) will get
350Hz and down. Not a good idea.

Kal

Kal,
Thanks for the information. I currently have my sub disconnected and was
not planning to use it as my new speakers have plenty of bass. Also, my sub
has it's own amp and active crossover setting. The amp manual says the
crossover sets the frequency at which bass tones are removed from the small
main speakers and sent to the subwoofer line out. It further states that if
the speakers are set to large the entire frequency range is sent to the
speakers and the crossover is ignored whether I have a sub or not. Does
that change anything?

Mike

Nope. Exactly what I would expect and completely in conformity with
what I described above. The controls on your sub are irrelevant since
they should be bypassed when used with the AVR. Also, there are very,
very few speakers that can do low bass better than a decent dedicated
sub and, moreover, using the sub will alleviate the workload for your
main speaker and amps.

Also, as others have stated, there's no reason to biamp unless the
original amp is completely inadequate. As stated above, using the suv
will help with that, too.

Kal

[Federico]

There are no benefits to biamping. Anything you may have been told to
the contrary is wrong. There are, however, plenty of things that can
go seriously bad when you biamp, from poor high/low matching to an
unexpected blast of mains hum destroying a tweeter.

Maybe there are no benefits this time.
But there are often mayor benefits in biamping.
F.

[Don Pearce[_2_]]

On Fri, 23 Jan 2009 10:24:12 +0100, "Federico"
wrote:


There are no benefits to biamping. Anything you may have been told to
the contrary is wrong. There are, however, plenty of things that can
go seriously bad when you biamp, from poor high/low matching to an
unexpected blast of mains hum destroying a tweeter.

Maybe there are no benefits this time.
But there are often mayor benefits in biamping.
F.


Like what? I have examined the subject in some detail, and I have yet
to find any. All I can find are disadvantages.

d

[Federico]

Maybe there are no benefits this time.
But there are often mayor benefits in biamping.
F.


Like what? I have examined the subject in some detail, and I have yet
to find any. All I can find are disadvantages.


I remember the first time I listened to a biamped Martin LE400 monitor...
Huge difference then mono-amped.
http://www.martin-audio.com/specific...Cdatasheet.pdf
F.

[Serge Auckland[_2_]]

"Federico" wrote in message
. ..
Maybe there are no benefits this time.
But there are often mayor benefits in biamping.
F.


Like what? I have examined the subject in some detail, and I have yet
to find any. All I can find are disadvantages.


I remember the first time I listened to a biamped Martin LE400 monitor...
Huge difference then mono-amped.
http://www.martin-audio.com/specific...Cdatasheet.pdf
F.

You're confusing Bi-amping with Active operation. Active operation, i.e.
using electronic crossovers before the power-amps, and no passive crossover
has many benefits, to do with headroom, accuracy of crossover, lower
distortions and avoidance of losses. Bi-amping, i.e. two power amps each
handling the full signal, and with passive crossovers retained have NO
benefit over a single amplifier unless that single amplifier is very poor to
the point of being broken.

In this regard, UK terminology i.e active and bi-amping seems more useful
than US terminology with refers just to biamping, sometimes correctly to
active biamping, but too often the word "active" is dropped.

S.
--
http://audiopages.googlepages.com

[Federico]

In this regard, UK terminology i.e active and bi-amping seems more useful
than US terminology with refers just to biamping, sometimes correctly to
active biamping, but too often the word "active" is dropped.

Thanks for the explanation!
I've been sound engineering for 20 years and I never heard of "active
biamping" before.
That's what I usually call "biamping".
Sorry Don, you were right!
F.

[Arny Krueger]

"Serge Auckland" wrote in
message

"Federico" wrote in message
. ..

Maybe there are no benefits this time.
But there are often mayor benefits in biamping.
F.

There are two kinds of biamping - active biamping and passive bi-amping.

Active biamping is so called because of the use of an active as opposed to a
passive crossover.

Most of my life biamping has meant what is now called active biamping. Maybe
a decade ago I started hearing about this weird passive biamping, which
amounts to using the bi-wiring terminals on a speaker with a separate power
amp for each set of terminals. That splits the lower and upper range
sections of the speaker up, and allows people to vary the balance between
the two sections. This mostly happens accidentally. Since it creates an
audible difference, it is perceived by most who experiment with it, as an
improvement.

The two main laws of audio tweaking a

1) If it does not in fact change anything audible, then it makes things
sound better.

2) If it does in fact change something that is audible, then it makes things
sound better.

;-)


Like what? I have examined the subject in some detail,
and I have yet to find any. All I can find are
disadvantages.

On balance it does allow making very broad-brush changes to a systems
sonics. Its a very crude form of equalization.

I remember the first time I listened to a biamped Martin
LE400 monitor... Huge difference then mono-amped.
http://www.martin-audio.com/specific...Cdatasheet.pdf
F.

More specifically:

"In active mode
the loudspeaker shall be bi-amped and operated with a
separate electronic controller. In passive mode, low and
high frequency sections shall be integrated by an
internal 1.2kHz passive crossover network."

The key phrase is "a separate electronic controller". IOW,an external active
crossover. However the design of this crossover is critical. None is
recommended and there is no documentation of how one would change the
performance of the loudspeaker.



Bi-amping, i.e. two
power amps each handling the full signal, and with
passive crossovers retained have NO benefit over a single
amplifier unless that single amplifier is very poor to
the point of being broken.

Agreed.

In this regard, UK terminology i.e active and bi-amping
seems more useful than US terminology with refers just to
biamping, sometimes correctly to active biamping, but too
often the word "active" is dropped.

In US terminology, the distinction between the two modes can be made, if the
terminology is used properly. The dropping of either active or passive is
not a nationality thing, it is the responsibility of the individual poster.

[vMike]

"Kalman Rubinson" wrote in message
...
On Thu, 22 Jan 2009 17:27:48 -0500, "vMike"
wrote:


"Kalman Rubinson" wrote in message
. ..
On Thu, 22 Jan 2009 16:29:39 -0500, "vMike"
wrote:

I am thinking of bi amping my speakers using the extra 2 amps on my 7.1
avr. Using the small v. large settings and adjusting the crossover, I
can
adjust the active crossover for the smalls to 350hz (matching the
speakers
crossover) so that the mids and tweeters primarily get upper
frequencies.
I do not have the ability to adjust the high pass crossover for the
larges
so the woofers will get the full range of frequencies which will then
use
the speaker's passive crossover.

Is this limitation going to negate the benefits of biamping?

mike


I do not know what AVR you have but, typically, most do not offer any
crossover for biamping at all and the crossover you see in "small" is
for crossing over to the subwoofer(s). They generally output full
bandwidth signals over both amps and let the built-in crossover in the
speaker handle the distribution.

Thus, if you use this setting with a 350Hz crossover, the HF part of
your biamped speakers will get 350Hz and up, the LF part of your
biamped speakers will also get 350Hz and up and your sub(s) will get
350Hz and down. Not a good idea.

Kal

Kal,
Thanks for the information. I currently have my sub disconnected and was
not planning to use it as my new speakers have plenty of bass. Also, my
sub
has it's own amp and active crossover setting. The amp manual says the
crossover sets the frequency at which bass tones are removed from the
small
main speakers and sent to the subwoofer line out. It further states that
if
the speakers are set to large the entire frequency range is sent to the
speakers and the crossover is ignored whether I have a sub or not. Does
that change anything?

Mike

Nope. Exactly what I would expect and completely in conformity with
what I described above. The controls on your sub are irrelevant since
they should be bypassed when used with the AVR. Also, there are very,
very few speakers that can do low bass better than a decent dedicated
sub and, moreover, using the sub will alleviate the workload for your
main speaker and amps.

Also, as others have stated, there's no reason to biamp unless the
original amp is completely inadequate. As stated above, using the suv
will help with that, too.

Kal



Thanks for your input. I just got new 802D's and they sound great, but I
was
thinking they might even sound better biamped as my amp is rated for only
150 and I had the extra amp in the system, but certainly don't want to
damage them. I think I will just leave it single amped. For now I have the
sub disconnected but will experiment with reconnecting with a very low
crossover.
mike

[vMike]

"Serge Auckland" wrote in message
...

"Federico" wrote in message
. ..
Maybe there are no benefits this time.
But there are often mayor benefits in biamping.
F.


Like what? I have examined the subject in some detail, and I have yet
to find any. All I can find are disadvantages.


I remember the first time I listened to a biamped Martin LE400 monitor...
Huge difference then mono-amped.
http://www.martin-audio.com/specific...Cdatasheet.pdf
F.

You're confusing Bi-amping with Active operation. Active operation, i.e.
using electronic crossovers before the power-amps, and no passive
crossover has many benefits, to do with headroom, accuracy of crossover,
lower distortions and avoidance of losses. Bi-amping, i.e. two power amps
each handling the full signal, and with passive crossovers retained have
NO benefit over a single amplifier unless that single amplifier is very
poor to the point of being broken.

In this regard, UK terminology i.e active and bi-amping seems more useful
than US terminology with refers just to biamping, sometimes correctly to
active biamping, but too often the word "active" is dropped.

S.
--
http://audiopages.googlepages.com
So if I can have active crossover on the tweeter and mid amp but passive on
the woofers amp, do you think there would be a benefit to biamping. My
speakers are 802D.

Mike

[Don Pearce[_2_]]

On Fri, 23 Jan 2009 08:44:07 -0500, "vMike"
wrote:


"Serge Auckland" wrote in message
...

"Federico" wrote in message
. ..
Maybe there are no benefits this time.
But there are often mayor benefits in biamping.
F.


Like what? I have examined the subject in some detail, and I have yet
to find any. All I can find are disadvantages.


I remember the first time I listened to a biamped Martin LE400 monitor...
Huge difference then mono-amped.
http://www.martin-audio.com/specific...Cdatasheet.pdf
F.

You're confusing Bi-amping with Active operation. Active operation, i.e.
using electronic crossovers before the power-amps, and no passive
crossover has many benefits, to do with headroom, accuracy of crossover,
lower distortions and avoidance of losses. Bi-amping, i.e. two power amps
each handling the full signal, and with passive crossovers retained have
NO benefit over a single amplifier unless that single amplifier is very
poor to the point of being broken.

In this regard, UK terminology i.e active and bi-amping seems more useful
than US terminology with refers just to biamping, sometimes correctly to
active biamping, but too often the word "active" is dropped.

S.
--
http://audiopages.googlepages.com
So if I can have active crossover on the tweeter and mid amp but passive on
the woofers amp, do you think there would be a benefit to biamping. My
speakers are 802D.

Mike


Let's examine the possible reasons for bi-amping:

1. Each amp handles a simpler signal, therefore distortion is less.
This holds no water. Signals are signals and amplifiers have no
knowledge of where they have been, and no preference for where they
will go. A signal containing both bass and treble is no harder to
handle than one containing just one of these.

2. You can drive the amplifiers harder. Again no. You don't divide the
power requirement in half when you split the signal. The power
requirement of an amplifier is determined by the peak voltage it must
deliver. For most music, this is unchanged by splitting the
frequencies - or rather some tunes will show higher treble levels,
while others show higher bass peaks. Those peaks are almost always as
big as the peaks in the combined signal, so all you are doing is
wasting power.

So much for bi-amping into a single speaker. There is a circumstance
where bi-amping is almost universal and very useful, and that is the
subwoofer. This is generally an add-on, not designed for the original
equipment and needs a range of adjustment to integrate it. Where the
subwoofer is integrated properly (the Willson Maxx speaker, for
example) there is again no reason to bi-amp, and a single amplifier
will do nicely.

d

[vMike]

Don Pearce wrote in message news:4979ca9b.87779703@localhost...
On Fri, 23 Jan 2009 08:44:07 -0500, "vMike"
wrote:


"Serge Auckland" wrote in message
.. .

"Federico" wrote in message
. ..
Maybe there are no benefits this time.
But there are often mayor benefits in biamping.
F.


Like what? I have examined the subject in some detail, and I have yet
to find any. All I can find are disadvantages.


I remember the first time I listened to a biamped Martin LE400
monitor...
Huge difference then mono-amped.
http://www.martin-audio.com/specific...Cdatasheet.pdf
F.

You're confusing Bi-amping with Active operation. Active operation, i.e.
using electronic crossovers before the power-amps, and no passive
crossover has many benefits, to do with headroom, accuracy of crossover,
lower distortions and avoidance of losses. Bi-amping, i.e. two power
amps
each handling the full signal, and with passive crossovers retained have
NO benefit over a single amplifier unless that single amplifier is very
poor to the point of being broken.

In this regard, UK terminology i.e active and bi-amping seems more
useful
than US terminology with refers just to biamping, sometimes correctly to
active biamping, but too often the word "active" is dropped.

S.
--
http://audiopages.googlepages.com
So if I can have active crossover on the tweeter and mid amp but passive
on
the woofers amp, do you think there would be a benefit to biamping. My
speakers are 802D.

Mike


Let's examine the possible reasons for bi-amping:

1. Each amp handles a simpler signal, therefore distortion is less.
This holds no water. Signals are signals and amplifiers have no
knowledge of where they have been, and no preference for where they
will go. A signal containing both bass and treble is no harder to
handle than one containing just one of these.

2. You can drive the amplifiers harder. Again no. You don't divide the
power requirement in half when you split the signal. The power
requirement of an amplifier is determined by the peak voltage it must
deliver. For most music, this is unchanged by splitting the
frequencies - or rather some tunes will show higher treble levels,
while others show higher bass peaks. Those peaks are almost always as
big as the peaks in the combined signal, so all you are doing is
wasting power.

So much for bi-amping into a single speaker. There is a circumstance
where bi-amping is almost universal and very useful, and that is the
subwoofer. This is generally an add-on, not designed for the original
equipment and needs a range of adjustment to integrate it. Where the
subwoofer is integrated properly (the Willson Maxx speaker, for
example) there is again no reason to bi-amp, and a single amplifier
will do nicely.

d
My understanding of the benefits of bi amp with active crossover (and this
may be incorrect) is that the passive crossover in the speaker sends small
amounts of current back to the amp through the speaker wires creating a
certain amount of distortion. Having active crossover with biamping
eliminates much of that distortion whereas having biamping with passive
crossover does nothing for that distortion.

Any thoughts on that?

mike

[Don Pearce[_2_]]

On Fri, 23 Jan 2009 09:03:32 -0500, "vMike"
wrote:

My understanding of the benefits of bi amp with active crossover (and this
may be incorrect) is that the passive crossover in the speaker sends small
amounts of current back to the amp through the speaker wires creating a
certain amount of distortion. Having active crossover with biamping
eliminates much of that distortion whereas having biamping with passive
crossover does nothing for that distortion.

Any thoughts on that?


Yes - it is incorrect. I'm not saying that all crossovers are entirely
free from distortion, but it is all relative. The speaker driver it is
feeding has distortion levels a hundred times as high.

The bit about sending tiny currents back, creating distortion is
actually technically incorrect too.

If you are really considering bi-amping in pursuit of better sound,
forget it. It isn't going to happen. All you will do is buy yourself
problems and grief getting it all set up. Spend the money on music.

d

[vMike]

Don Pearce wrote in message news:497acea0.88809281@localhost...
On Fri, 23 Jan 2009 09:03:32 -0500, "vMike"
wrote:

My understanding of the benefits of bi amp with active crossover (and this
may be incorrect) is that the passive crossover in the speaker sends small
amounts of current back to the amp through the speaker wires creating a
certain amount of distortion. Having active crossover with biamping
eliminates much of that distortion whereas having biamping with passive
crossover does nothing for that distortion.

Any thoughts on that?


Yes - it is incorrect. I'm not saying that all crossovers are entirely
free from distortion, but it is all relative. The speaker driver it is
feeding has distortion levels a hundred times as high.

The bit about sending tiny currents back, creating distortion is
actually technically incorrect too.

If you are really considering bi-amping in pursuit of better sound,
forget it. It isn't going to happen. All you will do is buy yourself
problems and grief getting it all set up. Spend the money on music.

d
ok enough said. I will leave things well enough alone. Music sounds great
already with what I have.
many thanks
mike

[[email protected]]

On Jan 23, 9:03*am, "vMike" wrote:
My understanding of the benefits of bi amp with
active crossover (and this may be incorrect) is that
the passive crossover in the speaker sends small
amounts of current back to the amp through the
speaker wires creating a certain amount of distortion. *
Having active crossover with biamping eliminates
much of that distortion whereas having biamping
with passive crossover does nothing for that distortion.

Any thoughts on that?

Yes, your understanding is incorrect on a number
of levels.

What the amplifier "sees" and how the load behaves
is not dependent upon individual components in
the speaker and its crossover, but on the sum total
of the load. ANd that is defined by the speaker's
impedance. The amplifier, the wires and all are utterly'
unaware of what causes individual features of that
electrical impedance, indeed, the only "individual
feature" of the impedance is the impedance.
And that impedance is not made any worse or better
by the presence of a competently designed speaker.

Second, the components of a passive crossover are far
and away, by orders of magnitude, more linear and thus
suffer from far less distortion than the drivers in the
speaker themselves.

Third, the vast majority of amplifiers that are even
moderately competently designed are essentially
insensitive to an extraordinary degree to the effects
of nonlinearities in the load as a matter of design.

Take all this together: IF you had an amplifier that
WAS sensitive to non-linear, nonresistive load
impedances, then, first, I would suggest you own
an incompetently designed or defective amplifier.
But if you STILL insisted on keeping it, then what
you'd find is that a reasonably competently
designed multi-way speaker with a passive
crossover would present a MORE linear, MORE
resistive and thus easier to drive load than you would
get with biamping.

And it would do it cheaper, more reliably and simpler.

[jakdedert]

Federico wrote:
In this regard, UK terminology i.e active and bi-amping seems more useful
than US terminology with refers just to biamping, sometimes correctly to
active biamping, but too often the word "active" is dropped.

Thanks for the explanation!
I've been sound engineering for 20 years and I never heard of "active
biamping" before.
That's what I usually call "biamping".
Sorry Don, you were right!
F.


I think it's all splitting hairs. The OP 'was' going to use an active
crossover. In fact, he has two: one in the receiver and one in the
subwoofer. Strictly speaking, just using a subwoofer is biamping,
although I usually think of it as splitting highs and lows at a much
higher frequency, it still fits the definition. 'Bi-wiring' is another
altogether different thing, that I never investigated; but AIU, doesn't
involve an active crossover.

I'm gonna go out on a limb (although a short and very stout one) and
define 'biamping' as using an active crossover ahead of two amplifier
channels with each reproducing a different part of the spectrum. It
doesn't matter whether there are additional passive filters after the
amplifier.

In fact, some professional sound reinforcement speakers are biamped
three-way designs, with a passive network to split the high/mids.
That's not so different from what the OP intended, although using a
three-way xover as a two way, by leaving the low output disconnected is
not indicated, IMO.

Also, it takes a lot more power to reproduce low frequencies, so the
amplifiers get progressively smaller as the frequency goes up. The old
rule of thumb used to be: double the power for mids as for highs, and
doubled again for the lows. IOW, (for example) 300 watts for lows, 150
for mids and 75 for highs. That was 'back when', and was never more
than a rough guide. Many variables are involved; xover frequencies,
power handling and relative efficiencies of the various sections
etc...but could get you at least somewhere near the ballpark.

jak

[Kalman Rubinson[_3_]]

On Fri, 23 Jan 2009 08:37:55 -0500, "vMike"
wrote:


Thanks for your input. I just got new 802D's and they sound great, but I
was
thinking they might even sound better biamped as my amp is rated for only
150 and I had the extra amp in the system, but certainly don't want to
damage them. I think I will just leave it single amped. For now I have the
sub disconnected but will experiment with reconnecting with a very low
crossover.

I have 802Ds also and strongly recommend that you do NOT
biamp them. The inbuilt crossovers are customized and
specialized and cannot be supplanted or improved on by
standard off-the-shelf external crossovers. Besides, in
order to do so, you would have to eviscerate your 802Ds and
remove the inbuilt crossovers to prevent interaction between
them and the new external crossover.

IMHO, decent 150w should be OK for the 802Ds but is not
generous. I am more comfortable with 200-500w in my system.
All that depends on your room, program material and
listening preferences. Certainly, adding the subwoofer so
that the lowest frequencies are rerouted to the sub will
make that 150w even more effective.

If after all is said and done, you feel the need for more
power, simply add a really good and powerful amp in place of
the one that is in your system now.

Kal

[Trevor Wilson[_2_]]

Don Pearce wrote in message news:4978ebf2.30778437@localhost...
On Thu, 22 Jan 2009 16:29:39 -0500, "vMike"
wrote:

I am thinking of bi amping my speakers using the extra 2 amps on my 7.1
avr. Using the small v. large settings and adjusting the crossover, I can
adjust the active crossover for the smalls to 350hz (matching the speakers
crossover) so that the mids and tweeters primarily get upper frequencies.
I do not have the ability to adjust the high pass crossover for the larges
so the woofers will get the full range of frequencies which will then use
the speaker's passive crossover.

Is this limitation going to negate the benefits of biamping?

mike




There are no benefits to biamping.

**WTF?!!???!!! There *may* be huge benefits to biamp some speakers. Huge,
massive, instantly noticable benefits. Two, small amps, can easily be shown,
under certain circumstances, to outperform a much larger amp. In theory and
in practice.

Anything you may have been told to
the contrary is wrong. There are, however, plenty of things that can
go seriously bad when you biamp, from poor high/low matching to an
unexpected blast of mains hum destroying a tweeter.

**********. A series capacitor will sort that issue out. In fact, many
speaker manufacturers, whose speakers are already set up for bi-amping
maintain such a cap for just such a purpose.


--
Trevor Wilson
www.rageaudio.com.au

[Trevor Wilson[_2_]]

"vMike" wrote in message
...

Don Pearce wrote in message news:4979ca9b.87779703@localhost...
On Fri, 23 Jan 2009 08:44:07 -0500, "vMike"
wrote:


"Serge Auckland" wrote in message
. ..

"Federico" wrote in message
. ..
Maybe there are no benefits this time.
But there are often mayor benefits in biamping.
F.


Like what? I have examined the subject in some detail, and I have yet
to find any. All I can find are disadvantages.


I remember the first time I listened to a biamped Martin LE400
monitor...
Huge difference then mono-amped.
http://www.martin-audio.com/specific...Cdatasheet.pdf
F.

You're confusing Bi-amping with Active operation. Active operation,
i.e.
using electronic crossovers before the power-amps, and no passive
crossover has many benefits, to do with headroom, accuracy of
crossover,
lower distortions and avoidance of losses. Bi-amping, i.e. two power
amps
each handling the full signal, and with passive crossovers retained
have
NO benefit over a single amplifier unless that single amplifier is very
poor to the point of being broken.

In this regard, UK terminology i.e active and bi-amping seems more
useful
than US terminology with refers just to biamping, sometimes correctly
to
active biamping, but too often the word "active" is dropped.

S.
--
http://audiopages.googlepages.com
So if I can have active crossover on the tweeter and mid amp but passive
on
the woofers amp, do you think there would be a benefit to biamping. My
speakers are 802D.

Mike


Let's examine the possible reasons for bi-amping:

1. Each amp handles a simpler signal, therefore distortion is less.
This holds no water. Signals are signals and amplifiers have no
knowledge of where they have been, and no preference for where they
will go. A signal containing both bass and treble is no harder to
handle than one containing just one of these.

2. You can drive the amplifiers harder. Again no. You don't divide the
power requirement in half when you split the signal. The power
requirement of an amplifier is determined by the peak voltage it must
deliver. For most music, this is unchanged by splitting the
frequencies - or rather some tunes will show higher treble levels,
while others show higher bass peaks. Those peaks are almost always as
big as the peaks in the combined signal, so all you are doing is
wasting power.

So much for bi-amping into a single speaker. There is a circumstance
where bi-amping is almost universal and very useful, and that is the
subwoofer. This is generally an add-on, not designed for the original
equipment and needs a range of adjustment to integrate it. Where the
subwoofer is integrated properly (the Willson Maxx speaker, for
example) there is again no reason to bi-amp, and a single amplifier
will do nicely.

d
My understanding of the benefits of bi amp with active crossover (and this
may be incorrect) is that the passive crossover in the speaker sends small
amounts of current back to the amp through the speaker wires creating a
certain amount of distortion. Having active crossover with biamping
eliminates much of that distortion whereas having biamping with passive
crossover does nothing for that distortion.

**No. Not correct. Bi-amping does impart some serous benefits to some
systems, however. To explain the advantages of bi-amping, I really need to
draw pretty pictures, but, I'll explain as best as I am able:

First off: Ignore the issue of POWER. We need to concentrate on Volts and
Amps (yes, I know power is a product of the two).

Image a hypothetical 30 Hz bass signal of (say) 60 Volts p-p. This
corresponds to 56 Watts continuous (@ 8 Ohms).
Imagine that at the same time, the amplifier must also deliver a 3kHz HF
signal of (say) 40 Volts p-p. This corresponds to 25 Watts (@ 8 Ohms)

All very well, you might say, as this is well within the capabilities of
your (hypothetical) 100 Watt (@ 8 Ohm) amplifier.

Not so fast.

Thanks to 'superposition' the p-p Voltages need to be added together first.
This will give us a total envelope of 100 Volts p-p. 100 Volts p-p is
equivalent to 156 Watts @ 8 Ohms.

Result - Voltage limiting (aka: Clipping).

In the above example, a 60 watt amp for bass and a 40 Watt amp for HF *may*
be more suitable (under the specific circumstances above) than a larger amp.

There are good reasons why every large sound reinforcement system is
multi-amped. It conveys serious advantages in power capacity and crossover
flexibility.

NB: None of these advantages may necessarily be realised in a domestic
situation. I have, however, worked on a number of domestic systems
(admittedly, quite large and power hungry ones) where multi-amping worked
exceptionally well.

The above assumes, of course, that a proper external crossover is used.


--
Trevor Wilson
www.rageaudio.com.au

[Don Pearce[_2_]]

On Sat, 24 Jan 2009 11:47:50 +1100, "Trevor Wilson"
wrote:

There are no benefits to biamping.

**WTF?!!???!!! There *may* be huge benefits to biamp some speakers. Huge,
massive, instantly noticable benefits. Two, small amps, can easily be shown,
under certain circumstances, to outperform a much larger amp. In theory and
in practice.

Wrong. Theory says no such thing, and neither does practice. Unless
you have a very peculiar "certain circumstances", which I think we are
probably not discussing - just normal audio reproduction.

d

[Trevor Wilson[_2_]]

Don Pearce wrote in message news:497accaa.153843093@localhost...
On Sat, 24 Jan 2009 11:47:50 +1100, "Trevor Wilson"
wrote:

There are no benefits to biamping.

**WTF?!!???!!! There *may* be huge benefits to biamp some speakers. Huge,
massive, instantly noticable benefits. Two, small amps, can easily be
shown,
under certain circumstances, to outperform a much larger amp. In theory
and
in practice.

Wrong.

**Nope. Absolutely correct.

Theory says no such thing, and neither does practice.

**Sure it does. Hit your old text books and look up: 'Superposition'. The
practice is evidenced by thousands of professional sound reinforcement
systems, which use bi-amping.

Unless
you have a very peculiar "certain circumstances", which I think we are
probably not discussing - just normal audio reproduction.

**Just ordinary audio reproduction. Biamping can be shown to work. See my
other post. I'll even post some CRO shots I took last week to demonstrate
the principle.

Go to alt.binaries.schematics.electronics. Look for the post entitled:
Bi-Amping. There are three CRO photos in the post. It is pretty much
self-explanatory.


--
Trevor Wilson
www.rageaudio.com.au

[Don Pearce[_2_]]

On Sat, 24 Jan 2009 20:10:25 +1100, "Trevor Wilson"
wrote:




Don Pearce wrote in message news:497accaa.153843093@localhost...
On Sat, 24 Jan 2009 11:47:50 +1100, "Trevor Wilson"
wrote:

There are no benefits to biamping.

**WTF?!!???!!! There *may* be huge benefits to biamp some speakers. Huge,
massive, instantly noticable benefits. Two, small amps, can easily be
shown,
under certain circumstances, to outperform a much larger amp. In theory
and
in practice.

Wrong.

**Nope. Absolutely correct.

Theory says no such thing, and neither does practice.

**Sure it does. Hit your old text books and look up: 'Superposition'. The
practice is evidenced by thousands of professional sound reinforcement
systems, which use bi-amping.


I know exactly what superposition is - it is the linear addition of
waveforms. Superposition is exactly what tells you that you don't need
to bi-amp. And of course if it was technically necessary (or
beneficial) to bi-amp, then simply doing that would make no sense -
hundreds of amps would be what you need.

Unless
you have a very peculiar "certain circumstances", which I think we are
probably not discussing - just normal audio reproduction.

**Just ordinary audio reproduction. Biamping can be shown to work. See my
other post. I'll even post some CRO shots I took last week to demonstrate
the principle.

Go to alt.binaries.schematics.electronics. Look for the post entitled:
Bi-Amping. There are three CRO photos in the post. It is pretty much
self-explanatory.

My news service is text only. Put them somewhere (your web space) I
can see them and I will have a look. But I will say right now that if
you can see the "problem" on a CRO then you have some other really
serious problem, because a CRO is far too blunt a tool to see small
audio nuances.

d

[Trevor Wilson[_2_]]

Don Pearce wrote in message news:497bdbbb.157700203@localhost...
On Sat, 24 Jan 2009 20:10:25 +1100, "Trevor Wilson"
wrote:




Don Pearce wrote in message news:497accaa.153843093@localhost...
On Sat, 24 Jan 2009 11:47:50 +1100, "Trevor Wilson"
wrote:

There are no benefits to biamping.

**WTF?!!???!!! There *may* be huge benefits to biamp some speakers.
Huge,
massive, instantly noticable benefits. Two, small amps, can easily be
shown,
under certain circumstances, to outperform a much larger amp. In theory
and
in practice.

Wrong.

**Nope. Absolutely correct.

Theory says no such thing, and neither does practice.

**Sure it does. Hit your old text books and look up: 'Superposition'. The
practice is evidenced by thousands of professional sound reinforcement
systems, which use bi-amping.


I know exactly what superposition is - it is the linear addition of
waveforms.

**Then you know why bi-amping *may* be helpful.

Superposition is exactly what tells you that you don't need
to bi-amp. And of course if it was technically necessary (or
beneficial) to bi-amp, then simply doing that would make no sense -
hundreds of amps would be what you need.

**I take your point, but big sound reinforcement systems may use upwards of
seven or eight crossover points and amplifiers for each. In fact, I've seen
quite a few recent, surround sound amps which use bi or tri-amping. I
promise you: The ONLY reason these guys do it, is to reduce costs.


Unless
you have a very peculiar "certain circumstances", which I think we are
probably not discussing - just normal audio reproduction.

**Just ordinary audio reproduction. Biamping can be shown to work. See my
other post. I'll even post some CRO shots I took last week to demonstrate
the principle.

Go to alt.binaries.schematics.electronics. Look for the post entitled:
Bi-Amping. There are three CRO photos in the post. It is pretty much
self-explanatory.

My news service is text only. Put them somewhere (your web space) I
can see them and I will have a look. But I will say right now that if
you can see the "problem" on a CRO then you have some other really
serious problem, because a CRO is far too blunt a tool to see small
audio nuances.

**It's not a small audio nuance. It can be, system depending, a dramatic and
substantial difference. I'll whack 'em up on my site tomorrow. It's not as
easy as posting to a newsgroup.


--
Trevor Wilson
www.rageaudio.com.au

[Don Pearce[_2_]]

On Sat, 24 Jan 2009 20:40:25 +1100, "Trevor Wilson"
wrote:




Don Pearce wrote in message news:497bdbbb.157700203@localhost...
On Sat, 24 Jan 2009 20:10:25 +1100, "Trevor Wilson"
wrote:




Don Pearce wrote in message news:497accaa.153843093@localhost...
On Sat, 24 Jan 2009 11:47:50 +1100, "Trevor Wilson"
wrote:

There are no benefits to biamping.

**WTF?!!???!!! There *may* be huge benefits to biamp some speakers.
Huge,
massive, instantly noticable benefits. Two, small amps, can easily be
shown,
under certain circumstances, to outperform a much larger amp. In theory
and
in practice.

Wrong.

**Nope. Absolutely correct.

Theory says no such thing, and neither does practice.

**Sure it does. Hit your old text books and look up: 'Superposition'. The
practice is evidenced by thousands of professional sound reinforcement
systems, which use bi-amping.


I know exactly what superposition is - it is the linear addition of
waveforms.

**Then you know why bi-amping *may* be helpful.

Superposition is exactly what tells you that you don't need
to bi-amp. And of course if it was technically necessary (or
beneficial) to bi-amp, then simply doing that would make no sense -
hundreds of amps would be what you need.

**I take your point, but big sound reinforcement systems may use upwards of
seven or eight crossover points and amplifiers for each. In fact, I've seen
quite a few recent, surround sound amps which use bi or tri-amping. I
promise you: The ONLY reason these guys do it, is to reduce costs.


These are systems in which you need individual control - from the
console - of levels to all the individual speakers in order to
successfully ring out the system in each new venue. It is not done
because it is better but because it is vital. It also ensures massive
redundancy so the whole thing doesn't fall silent when one amplifier
fails. This has nothing to do with bi-amping a domestic system.


Unless
you have a very peculiar "certain circumstances", which I think we are
probably not discussing - just normal audio reproduction.

**Just ordinary audio reproduction. Biamping can be shown to work. See my
other post. I'll even post some CRO shots I took last week to demonstrate
the principle.

Go to alt.binaries.schematics.electronics. Look for the post entitled:
Bi-Amping. There are three CRO photos in the post. It is pretty much
self-explanatory.

My news service is text only. Put them somewhere (your web space) I
can see them and I will have a look. But I will say right now that if
you can see the "problem" on a CRO then you have some other really
serious problem, because a CRO is far too blunt a tool to see small
audio nuances.

**It's not a small audio nuance. It can be, system depending, a dramatic and
substantial difference. I'll whack 'em up on my site tomorrow. It's not as
easy as posting to a newsgroup.

I look forwards to it.

d

[Peter Larsen[_3_]]

Trevor Wilson wrote:

Don Pearce wrote in message news:4978ebf2.30778437@localhost...

On Thu, 22 Jan 2009 16:29:39 -0500, "vMike"

wrote:

I am thinking of bi amping my speakers using the extra 2 amps on
my 7.1 avr. Using the small v. large settings and adjusting the
crossover, I can adjust the active crossover for the smalls to
350hz (matching the speakers crossover) so that the mids and
tweeters primarily get upper frequencies. I do not have the ability
to adjust the high pass crossover for the larges so the woofers
will get the full range of frequencies which will then use the
speaker's passive crossover.

Is this limitation going to negate the benefits of biamping?

Just biampling is in my opinion plain silly. If you want to use a dedicated
amplifier for each loudspeaker unit, then do it right. Rignt means that you
should use an active cross-over and the means required to ensure that the
acoustic output from each and every loudspeaker unit is exactly what the
filter math says it should be. There is no less work in optimizing an active
filter than in optimizing a passive high level filter, some loudspeaker
design software can do both.

mike


Kind regards

Peter Larsen

[Kalman Rubinson]

On Sat, 24 Jan 2009 11:47:50 +1100, "Trevor Wilson"
wrote:

**WTF?!!???!!! There *may* be huge benefits to biamp some speakers. Huge,
massive, instantly noticable benefits. Two, small amps, can easily be shown,
under certain circumstances, to outperform a much larger amp. In theory and
in practice.

Anything you may have been told to
the contrary is wrong. There are, however, plenty of things that can
go seriously bad when you biamp, from poor high/low matching to an
unexpected blast of mains hum destroying a tweeter.

**********. A series capacitor will sort that issue out. In fact, many
speaker manufacturers, whose speakers are already set up for bi-amping
maintain such a cap for just such a purpose.

[Trevor Wilson[_2_]]

Don Pearce wrote in message news:497bdbbb.157700203@localhost...
On Sat, 24 Jan 2009 20:10:25 +1100, "Trevor Wilson"
wrote:




Don Pearce wrote in message news:497accaa.153843093@localhost...
On Sat, 24 Jan 2009 11:47:50 +1100, "Trevor Wilson"
wrote:

There are no benefits to biamping.

**WTF?!!???!!! There *may* be huge benefits to biamp some speakers.
Huge,
massive, instantly noticable benefits. Two, small amps, can easily be
shown,
under certain circumstances, to outperform a much larger amp. In theory
and
in practice.

Wrong.

**Nope. Absolutely correct.

Theory says no such thing, and neither does practice.

**Sure it does. Hit your old text books and look up: 'Superposition'. The
practice is evidenced by thousands of professional sound reinforcement
systems, which use bi-amping.


I know exactly what superposition is - it is the linear addition of
waveforms. Superposition is exactly what tells you that you don't need
to bi-amp. And of course if it was technically necessary (or
beneficial) to bi-amp, then simply doing that would make no sense -
hundreds of amps would be what you need.

**Dunno why I didn't think of this yesterday, but, as music becomes
progressively more complex, it becomes somewhat more like white noise. As a
consequence, more of the larger, LF Voltage peaks will be subtracted by HF
signals. Hundreds of amps will not be required.


--
Trevor Wilson
www.rageaudio.com.au

[Trevor Wilson[_2_]]

Don Pearce wrote in message news:497ce58c.160213187@localhost...
On Sat, 24 Jan 2009 20:40:25 +1100, "Trevor Wilson"
wrote:




Don Pearce wrote in message news:497bdbbb.157700203@localhost...
On Sat, 24 Jan 2009 20:10:25 +1100, "Trevor Wilson"
wrote:




Don Pearce wrote in message news:497accaa.153843093@localhost...
On Sat, 24 Jan 2009 11:47:50 +1100, "Trevor Wilson"
wrote:

There are no benefits to biamping.

**WTF?!!???!!! There *may* be huge benefits to biamp some speakers.
Huge,
massive, instantly noticable benefits. Two, small amps, can easily be
shown,
under certain circumstances, to outperform a much larger amp. In
theory
and
in practice.

Wrong.

**Nope. Absolutely correct.

Theory says no such thing, and neither does practice.

**Sure it does. Hit your old text books and look up: 'Superposition'.
The
practice is evidenced by thousands of professional sound reinforcement
systems, which use bi-amping.


I know exactly what superposition is - it is the linear addition of
waveforms.

**Then you know why bi-amping *may* be helpful.

Superposition is exactly what tells you that you don't need
to bi-amp. And of course if it was technically necessary (or
beneficial) to bi-amp, then simply doing that would make no sense -
hundreds of amps would be what you need.

**I take your point, but big sound reinforcement systems may use upwards
of
seven or eight crossover points and amplifiers for each. In fact, I've
seen
quite a few recent, surround sound amps which use bi or tri-amping. I
promise you: The ONLY reason these guys do it, is to reduce costs.


These are systems in which you need individual control - from the
console - of levels to all the individual speakers in order to
successfully ring out the system in each new venue. It is not done
because it is better but because it is vital. It also ensures massive
redundancy so the whole thing doesn't fall silent when one amplifier
fails.

**It is also done, because significant SPLs are required.

This has nothing to do with bi-amping a domestic system.

**That would depend on the domestic system.


--
Trevor Wilson
www.rageaudio.com.au

[Trevor Wilson[_2_]]

Don Pearce wrote in message news:497ce58c.160213187@localhost...
On Sat, 24 Jan 2009 20:40:25 +1100, "Trevor Wilson"
wrote:

I look forwards to it.

**Done. Go to:

www.rageaudio.com.au

Click on: Bi-amping.


--
Trevor Wilson
www.rageaudio.com.au

[Don Pearce[_2_]]

On Sun, 25 Jan 2009 08:57:12 +1100, "Trevor Wilson"
wrote:





Don Pearce wrote in message news:497ce58c.160213187@localhost...
On Sat, 24 Jan 2009 20:40:25 +1100, "Trevor Wilson"
wrote:

I look forwards to it.

**Done. Go to:

www.rageaudio.com.au

Click on: Bi-amping.

Yup - I was expecting to see something unexpected (if you see what I
mean), but I didn't. You just presented the pathological extreme case.

Here is some actual music. First the complete work - no crossover

http://81.174.169.10/odds/allfreq.gif

Now just the bass frequencies, crossover at 2.2kHz

http://81.174.169.10/odds/lowfreq.gif

Although the average power has dropped somewhat, the amplifier needed
to carry this signal is just the same as for the whole signal -
dictated of course by signal peaks.

And finally the HF, above 2.2kHz. Filtering is all done with a second
order crossover style filter.

http://81.174.169.10/odds/highfreq.gif

You absolutely need the full amplifier power for this part of the
signal - you can't get away with a lower power amp simply because the
LF signals have been stripped away.

And of course a single amplifier will do every bit as well as
bi-amping. The moral of the story is that it doesn't do to try to
extrapolate to the real world from sine waves.

Just FYI, the music is "I'm with you", a track by Avril Lavigne.

d

[Don Pearce[_2_]]

On Sun, 25 Jan 2009 08:13:44 +1100, "Trevor Wilson"
wrote:




Don Pearce wrote in message news:497bdbbb.157700203@localhost...
On Sat, 24 Jan 2009 20:10:25 +1100, "Trevor Wilson"
wrote:




Don Pearce wrote in message news:497accaa.153843093@localhost...
On Sat, 24 Jan 2009 11:47:50 +1100, "Trevor Wilson"
wrote:

There are no benefits to biamping.

**WTF?!!???!!! There *may* be huge benefits to biamp some speakers.
Huge,
massive, instantly noticable benefits. Two, small amps, can easily be
shown,
under certain circumstances, to outperform a much larger amp. In theory
and
in practice.

Wrong.

**Nope. Absolutely correct.

Theory says no such thing, and neither does practice.

**Sure it does. Hit your old text books and look up: 'Superposition'. The
practice is evidenced by thousands of professional sound reinforcement
systems, which use bi-amping.


I know exactly what superposition is - it is the linear addition of
waveforms. Superposition is exactly what tells you that you don't need
to bi-amp. And of course if it was technically necessary (or
beneficial) to bi-amp, then simply doing that would make no sense -
hundreds of amps would be what you need.

**Dunno why I didn't think of this yesterday, but, as music becomes
progressively more complex, it becomes somewhat more like white noise. As a
consequence, more of the larger, LF Voltage peaks will be subtracted by HF
signals. Hundreds of amps will not be required.

Don't understand what you are saying - how does an HF signal subtract
an LF peak?

d

[Peter Larsen[_3_]]

Don Pearce wrote:

Yup - I was expecting to see something unexpected (if you see what I
mean), but I didn't. You just presented the pathological extreme case.

Here is some actual music. First the complete work - no crossover

http://81.174.169.10/odds/allfreq.gif

Another pathological extreme case, this one of loudification ... O;-) ...
but realistic enough as it is what goes over the counter; just another
brick.

Just FYI, the music is "I'm with you", a track by Avril Lavigne.

d

Kind regards

Peter Larsen

[Don Pearce[_2_]]

On Sat, 24 Jan 2009 23:33:00 +0100, "Peter Larsen"
wrote:

Don Pearce wrote:

Yup - I was expecting to see something unexpected (if you see what I
mean), but I didn't. You just presented the pathological extreme case.

Here is some actual music. First the complete work - no crossover

http://81.174.169.10/odds/allfreq.gif

Another pathological extreme case, this one of loudification ... O;-) ...
but realistic enough as it is what goes over the counter; just another
brick.

Unfortunately not pathologically extreme, but very typical.

d

[Trevor Wilson[_2_]]

Don Pearce wrote in message news:497c94a9.205043093@localhost...
On Sun, 25 Jan 2009 08:13:44 +1100, "Trevor Wilson"
wrote:




Don Pearce wrote in message news:497bdbbb.157700203@localhost...
On Sat, 24 Jan 2009 20:10:25 +1100, "Trevor Wilson"
wrote:




Don Pearce wrote in message news:497accaa.153843093@localhost...
On Sat, 24 Jan 2009 11:47:50 +1100, "Trevor Wilson"
wrote:

There are no benefits to biamping.

**WTF?!!???!!! There *may* be huge benefits to biamp some speakers.
Huge,
massive, instantly noticable benefits. Two, small amps, can easily be
shown,
under certain circumstances, to outperform a much larger amp. In
theory
and
in practice.

Wrong.

**Nope. Absolutely correct.

Theory says no such thing, and neither does practice.

**Sure it does. Hit your old text books and look up: 'Superposition'.
The
practice is evidenced by thousands of professional sound reinforcement
systems, which use bi-amping.


I know exactly what superposition is - it is the linear addition of
waveforms. Superposition is exactly what tells you that you don't need
to bi-amp. And of course if it was technically necessary (or
beneficial) to bi-amp, then simply doing that would make no sense -
hundreds of amps would be what you need.

**Dunno why I didn't think of this yesterday, but, as music becomes
progressively more complex, it becomes somewhat more like white noise. As
a
consequence, more of the larger, LF Voltage peaks will be subtracted by HF
signals. Hundreds of amps will not be required.

Don't understand what you are saying - how does an HF signal subtract
an LF peak?

**Superposition.


--
Trevor Wilson
www.rageaudio.com.au

[Arny Krueger]

"Trevor Wilson" wrote
in message
Don Pearce wrote in message
news:497ce58c.160213187@localhost...
On Sat, 24 Jan 2009 20:40:25 +1100, "Trevor Wilson"
wrote:

I look forwards to it.

**Done. Go to:

www.rageaudio.com.au

Click on: Bi-amping.

3 scope traces, no text.

"page under construction'

[Arny Krueger]

Don Pearce wrote in message
news:497b908b.203989171@localhost

Just FYI, the music is "I'm with you", a track by Avril
Lavigne.

Must be atypical, because the example I did with a 4th order butterworth
crossover showed a nearly 7 dB difference, with the tweeter getting that
much less signal.

Also, tweeters are generally easier to make more efficient than woofers for
reasons relating to box size and the laws of physics.

If you biamp you get to at least benefit from the ability to make tweeters
more efficient than woofers.