[Thomas Thiele[_2_]]

Hi,

I'm just installing the wiring for passive monitors. Should I install
2x2 per monitor for bi-amping or not?
Does bi-amping have actual advantages or is it a kind of voodoo?
If yes what thinkness?
(4m and 6m length)

Thomas

[Scott Dorsey]

Thomas Thiele wrote:

I'm just installing the wiring for passive monitors. Should I install
2x2 per monitor for bi-amping or not?

You might as well.

Does bi-amping have actual advantages or is it a kind of voodoo?

The idea is that biamping will reduce the interaction between the two
drivers caused by the series resistance of the cable. There is no longer
as much series resistance shared by both tweeter and woofer.

If yes what thinkness?
(4m and 6m length)

Whatever you have around. 12ga is probably fine. 10ga might be better.
Use the finest stranding you can get; in Germany you can get all of these
really great finely-stranded cables at the hardware store which we cannot
easily get in the US.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Laurence Payne[_2_]]

On Thu, 04 Mar 2010 01:55:35 +0100, Thomas Thiele
wrote:

Hi,

I'm just installing the wiring for passive monitors. Should I install
2x2 per monitor for bi-amping or not?
Does bi-amping have actual advantages or is it a kind of voodoo?
If yes what thinkness?
(4m and 6m length)

Thomas


Bi-amping has some justification. Bi-wiring is something else, and is
merely audiophile voodoo.

For recording monitors it's perhaps more likely that a future upgrade
would be to active speakers, where the amplification is completely
integrated with the drivers.

[Geoff]

Thomas Thiele wrote:
Hi,

I'm just installing the wiring for passive monitors. Should I install
2x2 per monitor for bi-amping or not?
Does bi-amping have actual advantages or is it a kind of voodoo?
If yes what thinkness?
(4m and 6m length)

Bi-amping, or 'just' bi-wiring ?

geoff

[William Sommerwerck]

You're confusing bi-wiring with bi-amping. They're quite different things.

The former assumes that speaker cables are non-linear, and separating the
bass and treble will reduce intermodulation, and possibly other effects
caused by THE CABLES. This is almost certainly not true.

The latter is, in theory, the best way to drive a speaker. It allows higher
output before the amplifiers clip, and gives control not possible with a
passive crossover.

[[email protected]]

On 3/3/2010 6:04 PM, Laurence Payne wrote:

Bi-amping has some justification. Bi-wiring is something else, and is
merely audiophile voodoo.

Bi-wiring = Buy wire

[Meindert Sprang]

"Scott Dorsey" wrote in message
...
Thomas Thiele wrote:

I'm just installing the wiring for passive monitors. Should I install
2x2 per monitor for bi-amping or not?

You might as well.

Does bi-amping have actual advantages or is it a kind of voodoo?

The idea is that biamping will reduce the interaction between the two
drivers caused by the series resistance of the cable. There is no longer
as much series resistance shared by both tweeter and woofer.

Isn't the cross-over filter already taking care of that?

Meindert

[Thomas Thiele]

On 4 Mrz., 03:22, "William Sommerwerck"
wrote:

You're confusing bi-wiring with bi-amping. They're quite different things.

My posting was a little bit confusing.

So the questions a

1. Should I install 2 pairs of wiring for each monitor to have the
option to bi-amping/bi-wiring.
2. Does simple Bi-Wiring (same amp) have any real advantages or is it
voo-doo.
3. Is Bi-Amping a great solution or waste of money, too. Whats to
regard? Frequency crossover (since the passive one are still in de
box) ?

[Arny Krueger]

"Thomas Thiele" wrote in message


I'm just installing the wiring for passive monitors.

I'm with Scott. Get some 12 gauge stranded speaker wire, and you don't have
to worry.

Should I install 2x2 per monitor for bi-amping or not?

You are confusing bi-amping with bi-wiring. 2 vastly different things.
Furthermore, thanks to the obsessivness of audiophiles, we even have 2
different styles of bi-amping.

There is only one kind of bi-amping that can make any technical sense at
all, and that is where you use electronic crossovers and 2 power amps, one
separate channel for each half of 2-way speakers. That requires essentially
re-engineering the speaker. All else is BS technical vodoo.

Does bi-amping have actual advantages or is it a kind of voodoo?

Biwiring is almost entirely vodoo.

If yes what thinkness?

(4m and 6m length)

I'm with Scott. Get some 12 gauge stranded speaker wire, and you don't have
to worry.

One of the first rules of professional audio involves *not* listening to
audiophiles. They want to tell you how to choose mics and position them.
They've never touched a mic in their lives and would struggle to unfasten a
XLR because their beloved RCA jacks don't latch. They want to tell you how
to mix and master. They've never touched a fader in their lives and become
hysterical if you mention even the simplist signal processing. As a rule
they first need to remove their heads from where the sun shines not! :-(

[Arny Krueger]

"Meindert Sprang" wrote in
message
"Scott Dorsey" wrote in message
...
Thomas Thiele wrote:

I'm just installing the wiring for passive monitors.
Should I install 2x2 per monitor for bi-amping or not?

You might as well.

Does bi-amping have actual advantages or is it a kind
of voodoo?

Vodoo. If it wasn't for sighted evaluations, this audiophile urban legend,
like many others would have died decades ago.

The idea is that biamping will reduce the interaction
between the two drivers caused by the series resistance
of the cable. There is no longer as much series
resistance shared by both tweeter and woofer.

If the speaker cable is linear (including linear inductance and capacitance
as well as resistance) and good ones always are, the interaction between the
woofer and tweeter are effectively determined by the crosover.

Isn't the cross-over filter already taking care of that?

To a very, very large degree.

Biwiring can actually have miniscule measurable effects, but with reasonable
speaker cables, they are way down in the noise.

[Arny Krueger]

wrote in message


On 3/3/2010 6:04 PM, Laurence Payne wrote:

Bi-amping has some justification. Bi-wiring is
something else, and is merely audiophile voodoo.

Bi-wiring = Buy wire

Author: My good friend Tom Nousiane.

[Mike Rivers]

Thomas Thiele wrote:

1. Should I install 2 pairs of wiring for each monitor to have the
option to bi-amping/bi-wiring.

That's two questions. I assume that you are committed to putting the
power amplifier(s) at the opposite end of the wires as the speaker? This
will determine what kind of wiring to install.

2. Does simple Bi-Wiring (same amp) have any real advantages or is it
voo-doo.

With today's power amplifiers, it's voodoo. With tube amplifiers with output
transformers which have a measurable source impedance, there was some
justification for bi-wiring. But with a solid state amplifier that is
essentially
a constant voltage (load impedance independent as long as it can deliver
enough current) source, bi-wiring doesn't help anything.

3. Is Bi-Amping a great solution or waste of money, too. Whats to
regard? Frequency crossover (since the passive one are still in de
box) ?

Don't bother if you're only going to bi-wire, and use a single power
amplifier
at the other end of the cable. If you're likely to update to an
electronic crossover
and two power amplifiers, and maintain the installation with the power
going
through your wiring, then run two cables.

There are other options, however. You might want to put the crossover and
amplifiers close to the speaker, in which case you'd want only one cable
per
speaker, but you'd want it shielded, and probably two-conductor for balanced
wiring. Or you might want to put the crossover at the source end and the
power amplifiers at the speaker end, in which case you'd want two shielded
cables. Or you might jusst get powered speakers.

If this is going to be a once-in-a-lifetime cable pull, run both power
and low
level (speaker and "audio") cables, two of each for each speaker. Wire,
even
if it's never used, is cheaper than tearing out walls.



--
"Today's production equipment is IT based and cannot be operated without
a passing knowledge of computing, although it seems that it can be
operated without a passing knowledge of audio." - John Watkinson

[Arny Krueger]

"Thomas Thiele" wrote in message

On 4 Mrz., 03:22, "William Sommerwerck"
wrote:

You're confusing bi-wiring with bi-amping. They're quite
different things.

My posting was a little bit confusing.

So the questions a

1. Should I install 2 pairs of wiring for each monitor to
have the option to bi-amping/bi-wiring.

No, its a waste of time and money.

2. Does simple Bi-Wiring (same amp) have any real
advantages or is it voo-doo.

Almost entirely vodoo.

3. Is Bi-Amping a great solution or waste of money, too.


The classic bi-amping that is done with one amplifier per driver and minimal
to no passive crossovers is great technology if properly exploited. For one
thing it opens a lot of possibilities for making crossovers do a better job
of exploiting drivers. It allows using less powerful amplfiiers, and
matching amplifier size to the actual needs of the drivers. I think that in
a purely rational world most quality audio systems would now use this
technology. But, tradition is a powerful force and its not a black-and-white
situation in every case.

For example, good speakers in 1-2 cubic foot range tend to be pretty heavy
to heft around, even when implemented passively. Adding a 18-35 pound
amplfier to a 30-50 pound speaker can lead to an 80 pound contraption that
is as much fun to carry as a bag of cement.

People like to decouple the amplfiiers from the speakers for economic and
psychological reasons. If you have a serious failure in an active speaker
and scrap it you're throwing away both a power amp and the speaker. If they
are two different boxes, you can upgrade or replace either separately.

Whats to regard? Frequency crossover (since the passive
one are still in de box) ?

Well, that's one problem with trying to make a speaker that was designed
with a passive crossover into one with an active crossover. You may have
spent good money for the passive crossover, and now you're throwing it away.

If you want to use speakers with separate amplifiers and electronic
crossovers, then it is very rational to buy an ensemble of speaker drivers,
amplifiers and crossovers that were designed to work together. IOW get an
active speaker.

I think the technology and economics of most studio monitors say that the
logical way to make this conversion is to sell off the passive speaker and
re-invest in a new active one.

[Thomas Thiele]

On 4 Mrz., 13:57, "Arny Krueger" wrote:

Hi Mike and Arny,

I think the technology and economics of most studio monitors say that the
logical way to make this conversion is to sell off the passive speaker and
re-invest in a new active one.

So my conclusion at the end is: one cable per monitor.

There are other investments to make before a new monitor system.
And who knows how long I'll keep my new rooms now.

[Scott Dorsey]

William Sommerwerck wrote:
You're confusing bi-wiring with bi-amping. They're quite different things.

The former assumes that speaker cables are non-linear, and separating the
bass and treble will reduce intermodulation, and possibly other effects
caused by THE CABLES. This is almost certainly not true.

No. The point of biwiring is not that the cables are linear, but that
the cables are resistive.

Throw a resistor in series with your speaker... now if you have low
frequency information going through the woofer, the voltage drop through
the cable also affects the tweeter. The two drivers can modulate one
another due to the voltage drop.

I think the effect is extremely minimal and I have never been able to hear
it, but the theory is actually reasonable. And hell, cable is cheap, so you
might as well.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Scott Dorsey]

In article ,
Meindert Sprang wrote:
"Scott Dorsey" wrote in message
...
Thomas Thiele wrote:

I'm just installing the wiring for passive monitors. Should I install
2x2 per monitor for bi-amping or not?

You might as well.

Does bi-amping have actual advantages or is it a kind of voodoo?

The idea is that biamping will reduce the interaction between the two
drivers caused by the series resistance of the cable. There is no longer
as much series resistance shared by both tweeter and woofer.

Isn't the cross-over filter already taking care of that?

No, that's the point. The crossover filter needs to see the lowest possible
source impedance to work properly.

That is in fact where a lot of the weirdness using tube amps with modern
loudspeaker designs comes from; crossovers that are intended to see a lower
Z source. It also cases similar weirdness using older speaker designs
with modern amps.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[William Sommerwerck]

You're confusing bi-wiring with bi-amping. They're quite different
things.
The former assumes that speaker cables are non-linear, and separating the
bass and treble will reduce intermodulation, and possibly other effects
caused by THE CABLES. This is almost certainly not true.

No. The point of biwiring is not that the cables are linear, but that
the cables are resistive.

Throw a resistor in series with your speaker... now if you have low
frequency information going through the woofer, the voltage drop through
the cable also affects the tweeter. The two drivers can modulate one
another due to the voltage drop.

That's non-linearity -- and it's an incorrect explanation.

There's a basic rule of mathematics -- superposition -- that says, in a
linear system, the output of input A+B can be found by adding the separate
outputs of the A and B inputs applied individually.

As far as the currents representing the signals to the woofer and tweeter
are concerned, they "see" the resistance of a linear cable separately. There
is no interaction among them.

[Scott Dorsey]

Thomas Thiele wrote:
On 4 Mrz., 03:22, "William Sommerwerck"
wrote:

You're confusing bi-wiring with bi-amping. They're quite different things.

My posting was a little bit confusing.

So the questions a

1. Should I install 2 pairs of wiring for each monitor to have the
option to bi-amping/bi-wiring.

Yes. You can never have too much wiring in the wall.

2. Does simple Bi-Wiring (same amp) have any real advantages or is it
voo-doo.

I don't think it makes any real advantage but if you have extra cable
you might as well use it.

3. Is Bi-Amping a great solution or waste of money, too. Whats to
regard? Frequency crossover (since the passive one are still in de
box) ?

It can be a great thing or basically unnecessary, depending on your
system design. There are some real advantages to active crossovers, like
being able to make sharper filters and having filters that are not
dependant on the impedance curves of the speaker drivers. There are also
disadvantages, like having a lot more stuff in your signal path.

Pick a system that you like... if it uses an active crossover or a passive
crossover, then use whatever it's designed for. Get a monitor system
that sounds the way you want and then worry about what technology was used
to implement it.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Sean Conolly]

"Thomas Thiele" wrote in message
...
On 4 Mrz., 13:57, "Arny Krueger" wrote:

Hi Mike and Arny,

I think the technology and economics of most studio monitors say that the
logical way to make this conversion is to sell off the passive speaker
and
re-invest in a new active one.

So my conclusion at the end is: one cable per monitor.

There are other investments to make before a new monitor system.
And who knows how long I'll keep my new rooms now.

FWIW bi-amping....

For monitors I'll stick with whatever the speakers came with. If it's a good
speaker with a well designed cross-over, I'm probably not going to improve
it by bi-amping it and fiddling with the settings. If I want bi-amp then
I'll buy an active, bi-amp monitor and rely on the engineers to design it
properly.

Sean

[Arny Krueger]

"Scott Dorsey" wrote in message
...
William Sommerwerck wrote:
You're confusing bi-wiring with bi-amping. They're quite different things.

The former assumes that speaker cables are non-linear, and separating the
bass and treble will reduce intermodulation, and possibly other effects
caused by THE CABLES. This is almost certainly not true.

No. The point of biwiring is not that the cables are linear, but that
the cables are resistive.

Right, so fix that with copper.

Throw a resistor in series with your speaker... now if you have low
frequency information going through the woofer, the voltage drop through
the cable also affects the tweeter.

The crossover went away?

Letsay that there are two signals flowing through a cable, LF (destined for
the woofer) and HF (destined for the tweeter).

Add a series resistor. Both signals are attenuated by the resistance of the
resistor, but if the resistor and the cable are linear, then the attenuation
of each signal happens completely independently. There is no
cross-modulation without nonlinearity.

The two drivers can modulate one another due to the voltage drop.

Nope, not if the cable and resistor are linear. That's electrical circuits
225.


I think the effect is extremely minimal and I have never been able to hear
it, but the theory is actually reasonable. And hell, cable is cheap, so
you
might as well.

To me that's the best non-controversial argument. It's ironic that snake oil
cable vendors work so hard to inflate the price of copper. It's the low
price of copper that makes it such a good solution.

[Arny Krueger]

"William Sommerwerck" wrote in message
...
You're confusing bi-wiring with bi-amping. They're quite different
things.
The former assumes that speaker cables are non-linear, and separating
the
bass and treble will reduce intermodulation, and possibly other effects
caused by THE CABLES. This is almost certainly not true.

No. The point of biwiring is not that the cables are linear, but that
the cables are resistive.

Throw a resistor in series with your speaker... now if you have low
frequency information going through the woofer, the voltage drop through
the cable also affects the tweeter. The two drivers can modulate one
another due to the voltage drop.

That's non-linearity -- and it's an incorrect explanation.

Bingo!

There's a basic rule of mathematics -- superposition -- that says, in a
linear system, the output of input A+B can be found by adding the separate
outputs of the A and B inputs applied individually.

That's electrical circuits 225.

As far as the currents representing the signals to the woofer and tweeter
are concerned, they "see" the resistance of a linear cable separately.
There
is no interaction among them.

True as long as the inductance, capacitance, and resistance (including skin
effect) is linear. As a rule they are very linear. We're talking air-core
inductors and air-dielectric capacitance. Very linear!

[Laurence Payne[_2_]]

Would the real Arny Kreuger please stand up?

[Martin Haverland]

Arny Krueger schrieb:
"Thomas Thiele" wrote in message


I'm just installing the wiring for passive monitors.

I'm with Scott. Get some 12 gauge stranded speaker wire, and you don't have
to worry.

Should I install 2x2 per monitor for bi-amping or not?

You are confusing bi-amping with bi-wiring. 2 vastly different things.
Furthermore, thanks to the obsessivness of audiophiles, we even have 2
different styles of bi-amping.

There is only one kind of bi-amping that can make any technical sense at
all, and that is where you use electronic crossovers and 2 power amps, one
separate channel for each half of 2-way speakers. That requires essentially
re-engineering the speaker. All else is BS technical vodoo.

Does bi-amping have actual advantages or is it a kind of voodoo?

Biwiring is almost entirely vodoo.

If yes what thinkness?

(4m and 6m length)

I'm with Scott. Get some 12 gauge stranded speaker wire, and you don't have
to worry.

One of the first rules of professional audio involves *not* listening to
audiophiles. They want to tell you how to choose mics and position them.
They've never touched a mic in their lives and would struggle to unfasten a
XLR because their beloved RCA jacks don't latch. They want to tell you how
to mix and master. They've never touched a fader in their lives and become
hysterical if you mention even the simplist signal processing. As a rule
they first need to remove their heads from where the sun shines not! :-(



Certainly true.
I have to say that not only the so-called audiophiles can drive you
crazy with their weird terminology- it is the 'audiophile industy', that
is constantly working on making things less understandible...to sell
'special' proprietary voodoo technology.

A typical example
Today I listened to a Linn Ninka pair that sounded like crap to me
(well, for the money it costs) with one terminal wired to an Adcom amp
(which is a great amp btw.).
Then we listened to the Linns wired to 2 Adcoms with both terminal pairs
used.
That was a tremendous improvement.
I would call it 'bi-amping' with a strang3e kind of internal passive
crossover, but in Linn's weird terminology it is called :
'Bi-Wiring'...???
Apparently the internal passive crossover is designed for this procedure
only, because it sounds sooo much better. The 'recommended' method for
using only one amp is certainly a joke to drive customers into buying a
second amp after getting trapped-
But it comes worse, they sell a kind of active crossover for the speaker
model that is to be installed *after* the amp and from the outside to
the terminal of the speaker (well, if I understood it right from the
brochures...). Wow, if that is not an interesting concept *cough*. Don't
ask for the money a complete system costs...

Try to discuss bi-wiring with a guy who bought such a system to listen
to a live version of 'Money for nothing' because the guitar riff sounds
'soooo goood.'
Yesterday a customer asked me if he has to push the
Naim-preamp-system-interconnect-voodoo-cable to the left or the right
side of the Hafler studioamp.... You might know what I mean.
They are talking religion ('what they believe how things are
functioning'), not technology.
When I was a young live musician, we called them 'hi-fi guys'.
Unfortunately some of those guys believed they were real live sound
engineers. Worst sound you can get. Clueless mixing desasters...and
always it was the fault of the 'bad, bad sounding PA', hahaha....
I guess it was too many pots and no 'loudness' knob.

Personally, I prefer an active monitoring every day. The old K+H O98
still do it for me until I can afford buying O300D or Geithain RL's.
Triamped active design where you do not have to worry about anything
regarding wiring, impedance matching between amp and speakers, poor (or
expensive) passive crossovers or speaker cable resistance.

Kind regards,
Martin

[Peter Larsen[_3_]]

Meindert Sprang wrote:

"Scott Dorsey" wrote in message
...

Thomas Thiele wrote:

I'm just installing the wiring for passive monitors. Should I
install 2x2 per monitor for bi-amping or not?

You might as well.

Definitely install required cabling and then some, ie. install for putting 4
way's up later, you can always parallel unneded separate wires and it is
unpleasantly costly and difficult to upgrade to more wires later.

Remember: any wiring harness dimensioned to requirement will be too small
..... O;-)

Does bi-amping have actual advantages or is it a kind of voodoo?

Bi-amping is a poorly defined wording, I read the OP to suggest using the
passive x-overs of the loudspeakers, but driving each pair of bi-wire
connectors from a separate amp. Doing that has slight merit, but some. It
does not give you the full advantages of an electronic x-over, but it does
give you the advantage of not having to redo the existing passive in a
passive box as electronic.

The idea is that biamping will reduce the interaction between the two
drivers caused by the series resistance of the cable. There is no
longer as much series resistance shared by both tweeter and woofer.

Isn't the cross-over filter already taking care of that?

No, you need to consider the reverse direction of current, ie. imagine the
cross-over network driven by the loudspeaker units as generators and loaded
either with only an amplifier via half the x-over or with an amplifier and
the full cross-over loaded by the other units section. (For simplicity
considering a 2-way!).

Loading with the amplifier only, as you would with a full electronic
cross-over solution loads the loudspeaker unit with a dead short, loaading
with a long cable presents it with a bit of impedance and loading it with
cross-over and possibly also the other units cross-over and the other unit
with varying complex loads. This is all about the dampening of the unit, a
dead short proving the shortest settlting time and a complex ""high
impedance"" load the longest, a cross-over with attenuation could provide
such a load. We are NOT talking big effects here, this is about subtleties
that are NOT going to be obvious on any and all setups.

Some three or four years ago someone did the math over in rec.audio.tech and
found some special case where the difference between bi-wiring to the same
amp or not would be a 0.5 dB frequency response variation. The general
finding was and remains that the best to do when presented with a biwired
setup is to parallel all wires to all units for lowest possible cable
impedance.

IMO either use the passive, optimized, cross-over and be happy or use a
properly customized active cross-over and be very happy and totally
eliminate some of the possible intermodulation distortions. If you are
building yourself the cost of high quality passive components suggests that
you might as well go active ....

Meindert

Kind regards

Peter Larsen

[Neil Gould[_2_]]

Hi Thomas,

Thomas Thiele" wrote:
3. Is Bi-Amping a great solution or waste of money, too. Whats to
regard? Frequency crossover (since the passive one are still in de
box) ?

You've gotten a lot of good responses, so I'll only toss my $0.02 in
regarding bi-amping, since there are some variables that I haven't seen
discussed. I presume that your installation is for a small listening area
rather than an auditorium or arena, so much of the reason for biamping is
already negated. Also, today's power amps are almost all too powerful for
speakers with any decent level of efficiency, so there is no need to
increase the power available to low frequency drivers in small environments.

Decent speakers are designed to perform with the supplied components; the
physical behavior of the drivers and performance parameters of the enclosure
have been taken into consideration to make a speaker that delivers a decent
overall frequency response. Since these factors are fixed, the most likely
outcome would be that speaker performance would be degraded by inserting
active crossovers, as that will alter the drivers' behavior at the point of
crossover due to 1) a shift in center frequency, 2) different rolloff
characteristics at the crossover point, 3) reduced insertion loss, 4) a
change in allocation of power to the drivers, or most likely, all of the
above.

At the end of the day, if biamping was done perfectly by designing the
crossovers to match your passive crossover performance, your listening
environment will have a much greater impact on the audible quality of your
system than the change.

--
HTH,

Neil



--- news://freenews.netfront.net/ - complaints: ---

[Peter Larsen[_3_]]

Neil Gould wrote:

Decent speakers are designed to perform with the supplied components;
the physical behavior of the drivers and performance parameters of
the enclosure have been taken into consideration to make a speaker
that delivers a decent overall frequency response. Since these
factors are fixed, the most likely outcome would be that speaker
performance would be degraded by inserting active crossovers, as that
will alter the drivers' behavior at the point of crossover due to 1)
a shift in center frequency, 2) different rolloff characteristics at
the crossover point, 3) reduced insertion loss, 4) a change in
allocation of power to the drivers, or most likely, all of the above.

Which is why I used the wording "properly optimized".

At the end of the day, if biamping was done perfectly by designing the
crossovers to match your passive crossover performance, your listening
environment will have a much greater impact on the audible quality of
your system than the change.

Yes, but first use money on the acoustics.

Kind regards

Peter Larsen

[Neil Gould[_2_]]

"Peter Larsen" wrote in message
k...
Neil Gould wrote:

Decent speakers are designed to perform with the supplied components;
the physical behavior of the drivers and performance parameters of
the enclosure have been taken into consideration to make a speaker
that delivers a decent overall frequency response. Since these
factors are fixed, the most likely outcome would be that speaker
performance would be degraded by inserting active crossovers, as that
will alter the drivers' behavior at the point of crossover due to 1)
a shift in center frequency, 2) different rolloff characteristics at
the crossover point, 3) reduced insertion loss, 4) a change in
allocation of power to the drivers, or most likely, all of the above.

Which is why I used the wording "properly optimized".

As I wrote at the outset, I was only mentioning some items that I didn't see
in other posts. I didn't see "properly optimized" in your post... I did see
"properly customized", but it appeared to be in a different context than the
above, and I read a usage of "optimized" in that paragraph that seems to be
in the same context, but with a somewhat different conclusion.

At the end of the day, if biamping was done perfectly by designing the
crossovers to match your passive crossover performance, your listening
environment will have a much greater impact on the audible quality of
your system than the change.

Yes, but first use money on the acoustics.

"...but first..."? I _think_ we're in agreement, but, just to be clear, I'm
suggesting that Thomas drop the idea of bi-amping decent speakers that have
passive crossovers altogether and put the money where it might make an
audible difference. The details, above, were my rationale for taking that
position.

--
best regards,

Neil



--- news://freenews.netfront.net/ - complaints: ---

[Arny Krueger]

"Peter Larsen" wrote in message
k...

No, you need to consider the reverse direction of current, ie. imagine the
cross-over network driven by the loudspeaker units as generators and
loaded either with only an amplifier via half the x-over or with an
amplifier and the full cross-over loaded by the other units section. (For
simplicity considering a 2-way!).

There is no such reverse current unless you believe that the speaker has
negative impedance.

All that happens due to the so-called "back EMF" from the voice coil is that
the the impedance of the driver is higher than you would expect from
traditional resistance measurements.

Loudspeakers differ from other familair situations like dynamic braking in
vehicles in that loudspeaker propulsion systems are very, very inefficient.
Most of us know that a loudspeaker with 1% efficiency is a very efficient
speaker. That is partially due to the fact that for example a typical 8 ohm
loudspeaker starts out with a resistor of no less than 7.5 ohms in series
with all of the rest of it. Whatever the voice coil does because it is in a
magnetic field, is highly isolated from the speaker terminals.

[William Sommerwerck]

No, you need to consider the reverse direction of current, ie.
imagine the cross-over network driven by the loudspeaker units
as generators and loaded either with only an amplifier via half
the x-over or with an amplifier and the full cross-over loaded by
the other units section. (For simplicity considering a 2-way!).

There is no such reverse current unless you believe that the
speaker has negative impedance.

And that isn't what negative impedance is, anyway


Loudspeakers differ from other familair situations like dynamic
braking in vehicles in that loudspeaker propulsion systems are
very, very inefficient. Most of us know that a loudspeaker with
1% efficiency is a very efficient speaker.

It isn't, nor has it ever been. The early acoustic-suspension speakers were
around 1%, which was considered quite low. And despite the existance of
inexpensive high-powered amplifiers, almost every speaker currently made is
ported (rather than sealed) to get a bit more efficiency out of it. For all
practical purposes, the acoustic suspension speaker is dead.


That is partially due to the fact that for example a typical 8 ohm
loudspeaker starts out with a resistor of no less than 7.5 ohms
in series with all of the rest of it.

This is a fundamental -- and understandable -- misunderstanding. ALL the
current flowing through the voice coil -- whether resistive or reactive --
generates a magnetic field that moves the driver. * The energy "consumed" by
the driver's resistance is not wasted.

An "8 ohm" speaker whose impedance was wholly reactive would be no more or
less efficient than one with a wholly resistive impedance. The driver's
motion is determined by the current flowing through it, and nothing else
(assuming the Bl product is the same).


Whatever the voice coil does because it is in a magnetic
field, is highly isolated from the speaker terminals.

This is an interesting point. The more-reactive the driver's impedance, the
less-isolated it is (ignoring the crossover's effect, of course).

A few years ago, a British speaker manufacturer inveighed /against/ active
crossovers, claiming that passive crossovers did a better job isolating the
driver from the amplifier. The company apparently felt that having an
amplifier directly "look at" a reactive load was not a good thing! (There
are plenty of amplifiers, including modestly priced ones, that have no
trouble with electrostatic speakers.)

* I'm ignoring the phase angle between the reactive and resistive
components. But "8 ohms" is "8 ohms", regardless.

[Don Pearce[_3_]]

On Sun, 7 Mar 2010 05:06:10 -0800, "William Sommerwerck"
wrote:

An "8 ohm" speaker whose impedance was wholly reactive would be no more or
less efficient than one with a wholly resistive impedance. The driver's
motion is determined by the current flowing through it, and nothing else
(assuming the Bl product is the same).

A speaker whose impedance was wholly reactive would produce no sound.
The speaker acts as a transformer between the electrical signal and
the acoustic one, and all of the acoustic power it produces has to
appear as a resistive impedance term in the overall impedance. A
speaker that shifts air cannot be wholly reactive. The reactive term
is, to all intents and purposes, a leakage term that plays no part in
the signal transfer.

d

[William Sommerwerck]

"Don Pearce" wrote in message
...
On Sun, 7 Mar 2010 05:06:10 -0800, "William Sommerwerck"
wrote:

An "8 ohm" speaker whose impedance was wholly reactive would
be no more or less efficient than one with a wholly resistive impedance.
The driver's motion is determined by the current flowing through it, and
nothing else (assuming the Bl product is the same).

A speaker whose impedance was wholly reactive would produce no sound.
The speaker acts as a transformer between the electrical signal and
the acoustic one, and all of the acoustic power it produces has to
appear as a resistive impedance term in the overall impedance. A
speaker that shifts air cannot be wholly reactive. The reactive term
is, to all intents and purposes, a leakage term that plays no part in
the signal transfer.

What you're saying is correct, but the issue was about another matter. The
degree to which a driver is resistive or reactive has nothing to do with its
efficiency (as far as I know). I interpreted Arny's explanation as
suggesting that current flowing through the resistive component of a
driver's static impedance contributes nothing to its output, which is not
true.

Let's not turn this into a techno-megillah. Please.

[Don Pearce[_3_]]

On Sun, 7 Mar 2010 05:50:21 -0800, "William Sommerwerck"
wrote:

"Don Pearce" wrote in message
...
On Sun, 7 Mar 2010 05:06:10 -0800, "William Sommerwerck"
wrote:

An "8 ohm" speaker whose impedance was wholly reactive would
be no more or less efficient than one with a wholly resistive impedance.
The driver's motion is determined by the current flowing through it, and
nothing else (assuming the Bl product is the same).

A speaker whose impedance was wholly reactive would produce no sound.
The speaker acts as a transformer between the electrical signal and
the acoustic one, and all of the acoustic power it produces has to
appear as a resistive impedance term in the overall impedance. A
speaker that shifts air cannot be wholly reactive. The reactive term
is, to all intents and purposes, a leakage term that plays no part in
the signal transfer.

What you're saying is correct, but the issue was about another matter. The
degree to which a driver is resistive or reactive has nothing to do with its
efficiency (as far as I know). I interpreted Arny's explanation as
suggesting that current flowing through the resistive component of a
driver's static impedance contributes nothing to its output, which is not
true.

Let's not turn this into a techno-megillah. Please.


I haven't read the thread, so I don't know what he wrote, but what he
says is correct in essence in that the power dissipated in the coil
resistance can only appear as heat, never sound. I think maybe you are
as guilty as I of trying to make a techno-whatever-you-called-it.

d

[Peter Larsen[_3_]]

Neil Gould wrote:

Which is why I used the wording "properly optimized".

As I wrote at the outset, I was only mentioning some items that I
didn't see in other posts. I didn't see "properly optimized" in your
post... I did see "properly customized", but it appeared to be in a
different context than the above,

You are quite right. In this context "properly customized" and "properly
optimized" are interchangeable, but it is quite possibly less confusing to
use the exact wording when re-iterating.

Yes, but first use money on the acoustics.

"...but first..."? I _think_ we're in agreement, but, just to be
clear, I'm suggesting that Thomas drop the idea of bi-amping decent
speakers that have passive crossovers altogether and put the money
where it might make an audible difference. The details, above, were
my rationale for taking that position.

The primary benefit of biwiring is to the cable manufacturer and vendor,
bi-amping without a suitable active cross-over is a method for also
transferring hopefully excess funds to amplifier manufacturer and vendor. A
proper active system ... then we're talking and even that may have
shortcomings. For a simple example: to listen for the differences in sound
between electronic components a good fullrange speaker can be a very good
choice.

There is of course a scale, and I don' want to try to put my finger on the
optimum setup, but is possible to add so much to a signal path that an
compoment more or less gets lost in the general fog of distortion. And it is
possible to find program where many components more or less is totally
irrelevant and inaudible because it is plain miserable.

Which is to say that we are quite possibly facing the daunting perspecive of
perhaps not disagreeing.

Kind regards

Peter Larsen

[Peter Larsen[_3_]]

Arny Krueger wrote:

"Peter Larsen" wrote in message
k...

No, you need to consider the reverse direction of current, ie.
imagine the cross-over network driven by the loudspeaker units as
generators and loaded either with only an amplifier via half the
x-over or with an amplifier and the full cross-over loaded by the
other units section. (For simplicity considering a 2-way!).

There is no such reverse current unless you believe that the speaker
has negative impedance.

Oh yes, no contest, I just suggested a viewing angle that makes the concepts
simpler, the actual currents are regulated by Ohm's law and a loudspeaker
unit with a high internal impedance is not likely to be able to deliver
relevant power back to a near zero ohm powered up and unclipped amplifier.

All that happens due to the so-called "back EMF" from the voice coil
is that the the impedance of the driver is higher than you would
expect from traditional resistance measurements.

Loudspeakers differ from other familair situations like dynamic
braking in vehicles in that loudspeaker propulsion systems are very,
very inefficient.

Yes, for household implement type loudspeakers there is so little power lost
in the generation of sound that it is a suitable asumption that all the
power the amplifier delivers to the voice coil needs to be removed as heat.

Most of us know that a loudspeaker with 1%
efficiency is a very efficient speaker. That is partially due to the
fact that for example a typical 8 ohm loudspeaker starts out with a
resistor of no less than 7.5 ohms in series with all of the rest of
it. Whatever the voice coil does because it is in a magnetic field,
is highly isolated from the speaker terminals.

A helpful image, thanks!

Kind regards

Peter Larsen

[William Sommerwerck]

What you're saying is correct, but the issue was about another matter.
The degree to which a driver is resistive or reactive has nothing to do
with its efficiency (as far as I know). I interpreted Arny's explanation
as suggesting that current flowing through the resistive component of a
driver's static impedance contributes nothing to its output, which is not
true.

Let's not turn this into a techno-megillah. Please.

I haven't read the thread, so I don't know what he wrote, but what he
says is correct in essence in that the power dissipated in the coil
resistance can only appear as heat, never sound. I think maybe you
are as guilty as I of trying to make a techno-whatever-you-called-it.

A megillah is a long, drawn-out story.

You've neatly summed up the issue. Thanks.

You and Arny raised an interesting point I'd never thought about. But let's
let it drop here. We all have othe things to do.

[Scott Dorsey]

Arny Krueger wrote:
"Peter Larsen" wrote in message
. dk...

No, you need to consider the reverse direction of current, ie. imagine the
cross-over network driven by the loudspeaker units as generators and
loaded either with only an amplifier via half the x-over or with an
amplifier and the full cross-over loaded by the other units section. (For
simplicity considering a 2-way!).

There is no such reverse current unless you believe that the speaker has
negative impedance.

All that happens due to the so-called "back EMF" from the voice coil is that
the the impedance of the driver is higher than you would expect from
traditional resistance measurements.

What do you mean "all that happens is the impedance is higher?" What more
do you want?

The fact that the impedance of the driver varies with frequency as the result
of back-emf is a major, major problem and it's the main glitch in passive
crossover design.

Loudspeakers differ from other familair situations like dynamic braking in
vehicles in that loudspeaker propulsion systems are very, very inefficient.
Most of us know that a loudspeaker with 1% efficiency is a very efficient
speaker. That is partially due to the fact that for example a typical 8 ohm
loudspeaker starts out with a resistor of no less than 7.5 ohms in series
with all of the rest of it. Whatever the voice coil does because it is in a
magnetic field, is highly isolated from the speaker terminals.

Depends on the driver, but indeed the poor coupling is about the only
salvation poor crossover designers get.

On the other hand, we have zobel networks to deal with some of the worst of
the issues.

It's a wonder speakers work as well as they do. And by the standards of the
rest of the signal chain, they don't work very well at all.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Arny Krueger]

"William Sommerwerck" wrote in message
...
No, you need to consider the reverse direction of current, ie.
imagine the cross-over network driven by the loudspeaker units
as generators and loaded either with only an amplifier via half
the x-over or with an amplifier and the full cross-over loaded by
the other units section. (For simplicity considering a 2-way!).

There is no such reverse current unless you believe that the
speaker has negative impedance.

And that isn't what negative impedance is, anyway

It is one of the ways to have something with negative impedance.

Loudspeakers differ from other familair situations like dynamic
braking in vehicles in that loudspeaker propulsion systems are
very, very inefficient. Most of us know that a loudspeaker with
1% efficiency is a very efficient speaker.

It isn't, nor has it ever been. The early acoustic-suspension speakers
were
around 1%, which was considered quite low.

Yes, 1% was considered to be low at the time. But that was a historical
perspective, largely driven by the fact that making really good, powerful
audio amplifiers with tubes is a highly uneconomical enterprise. So the
general run of quality speaker was expected to be highly efficient.

In fact the origional AR-1 and the first AR-3s were be considered to be
moderately high efficiency by modern standards. I know this because I once
owned a pair of origional AR3s, about 20 years ago. Their 90 dB SPL/watt
efficiency was the bane of my existence at the time - the tweeters and mids
were fried, and I tried to mate them up with some modern dome drivers of
average or better efficiency. No problem with the tweeter, but the modern
dome (Morel) midrange had appreciably less efficiency than the old AR
woofer. The final answer was electronic crossovers and 3 separate stereo
power amps.

It's not uncommon to find home speakers with efficiency in the low 80s or
even less, particularly subwoofers. Average is more like 87 dB/watt.

And despite the existance of
inexpensive high-powered amplifiers, almost every speaker currently made
is
ported (rather than sealed) to get a bit more efficiency out of it.

There are tons of modern speakers that are in sealed boxes. Furthermore,
porting a speaker box does not give it that much gosh-much more efficiency.
The benefit of porting is a fraction of an octave worth of bass extension,
all other things being equal. Now you can take that bass extension as
efficiency or a smaller box, but the benefits are marginal.

In these days of highly efficient and inexpensive power amplifiers, few but
people involved with live sound care much about how efficient a speaker is,
within very broad limits.

For all practical purposes, the acoustic suspension speaker is dead.

True the sense that "Acoustic suspension" was a sales phrase with little
technical meaning. The so-called acoustic suspension speaker drivers still
had effective menchanical suspensions. They weren't even all that softly
suspended by modern standards.

That is partially due to the fact that for example a typical 8 ohm
loudspeaker starts out with a resistor of no less than 7.5 ohms
in series with all of the rest of it.

This is a fundamental -- and understandable -- misunderstanding. ALL the
current flowing through the voice coil -- whether resistive or reactive --
generates a magnetic field that moves the driver. * The energy "consumed"
by
the driver's resistance is not wasted.

You can't have it both ways. Either speakers have about 1% (plus/minus)
efficiency, as opposed to say 50 or 90 percent, or they waste most of the
energy that enters the driver's terminals. There are drivers that are 30-50%
efficient, but they are compression drivers for use with waveguides (horns).

An "8 ohm" speaker whose impedance was wholly reactive would be no more or
less efficient than one with a wholly resistive impedance.

I guess you forgot that a pure reactance wastes no energy, it just stores it
and returns it later on.

The driver's
motion is determined by the current flowing through it, and nothing else
(assuming the Bl product is the same).

When there is a 7.5 ohm DC resistance that is effectively in series with a
so-called 8 ohm speaker, the current flowing through the speaker heats up
the resistor and the energy is lost to the environment without making any
sound.

Whatever the voice coil does because it is in a magnetic
field, is highly isolated from the speaker terminals.

This is an interesting point. The more-reactive the driver's impedance,
the
less-isolated it is (ignoring the crossover's effect, of course).

I prefer to look at it as being less resistive.