Quad 606 with a Quad 405
 

"MiNe 109" wrote in message

In article ,
"Arny Krueger" wrote:

"MiNe 109" wrote in message


In article
,

"Arny Krueger" wrote:

Bi-amped has traditionally meant, and means in most
audio circles to this day, active crossover, two power
amps, two-way speaker system.

Hence the term 'passive bi-amping' to distinguish it
from your definition.

There's a whole forest of made-up terms out there for
this sort of weirdness:

vertical bi-amp

horizontal bi-amp

come to mind.

Those are different configurations of passive bi-amping.

A possible case for the passive method is as an
intermediate step for one who wishes to complete the
active system later.

Almost everything is possible in the world of
imagination. Doesn't make many of them anything like a
good idea.

This is one of the good ones.

For the sales guy!

Here's a bad idea:
off-the-shelf electronic crossover to replace a specific
passive crossover.

That might not be any worse than using two power amps with mismatched gains,
which is what the combination that OP mentioned had. Yes, the OP had been
told a tall tale about matched gains, but the relevant facts told a
different story. The amps did not have matched gains. There was more than
enough gain difference to change the basic sound of the Spendors.

OTOH, traditional biamping is becoming a trend, as a
delivered complete engineered speaker/amp system, not a
random collection of parts thrown together by clueless
audiophile dupes and shyster sales hacks.

How are amps from the same maker said to have the same
gain a "random collection of parts"?

You're apparently not following the whole thread, Stephen. Yes, the OP said
that he was told that he had two amps from the same maker that had the same
gain. When we looked at the relevant facts, we found that someone had been
telling him audio fairy stories. The amps don't have matched gain, no matter
what he was told.

Quad 606 with a Quad 405
 

In article , Arny
Krueger
wrote:
"Jim Lesurf" wrote in message

In article , Bob Latham
wrote:

[snip]

Where have you seen any figures to support the assertion that the
"majority" would say this? And would it mean more than, "The magazines
keep saying it does"? :-)

I'd like to see a reference to an article in an audio ragazine with
meaninful circultation about an actual high end product that bi-amps
without an active product. For example, has Stereophile or HFN ever
reviewed a biamped speaker with no active crossover?

I have a vague feeling that HFN may have once reviewed the 'systems' that
some people put together. In general, of course, that won't be anything
that was intended by either the speaker manufacturer or the amp
manufacturer.

However IIRC back in the 1980's there was a UK fad for using multiple Naim
power amps to 'bi amp' the Linn Isobarik. Not sure if Naim or Linn pushed
the idea, but some dealers and 'subjective reviewers' did at the time.

Personally, I disliked both the Isobarik, and the Naim amps. So for me the
main benefit was that it piled the items I didn't want somewhere away from
where I had to encounter them. :-)

FWIW The Isobarik had an impedance that went south at LF, and the Naim
amps of the period had an output 0.22 Ohm series resistor and limited
current capability. So the Naim/Isobarik system did have a different
response to using an amp with low output impedance and decent current
capability. However I tended to make the choice here that wasn't the one
touted in magazines at the time. :-)

At the time Linn dealers used to insist that 'stereo image' was a myth.
Perhaps because you couldn't get one when using Isobariks. ;-

The most dramatic change I ever heard was in a shop when the removed the
Isobariks and tried Quad 63's. From awful to excellent. They shop droids
hated the Quads. But then they were unable to hear that one of the tweeters
in one of the Isobariks was busted... :-)

[snip]

Ironically, there's an argument that says that putting a normal woofer
in parallel with a highly reactive tweeter through a passive crossover
makes the reactive tweeter an easier load to drive. The signal through
the woofer drives the power amp output stage up its load line where the
out-of-phase current for the tweeters is coming from output transistors
that are already partially saturated from driving the woofer. The
voltage across the output transistors and the power dissipation in the
output stage is therefore reduced.

A few months ago there was someone putting a flawed argument forwards on
the 'audioholics' website in a thread about bi-wiring.

The wording of the claims 'evolved' as it was challenged. However it tended
to be based on saying there was a form of 'intermodulation' occurring in
conventional wiring that biwiring removed.

Mysterious consequences were described such as components in the spectrum
that an FFT could not show. Doubters were treated as being unable to grasp
the reality as they lacked the scientific insight of the idea's presenter.
;-

The argument used was incorrect, or at least inappropriate, and thus lead
to an wrong conclusion. I did an analysis and it was another example of how
a simple misconception can mislead, but a detailed analysis takes ages to
show what a good engineer would have thought in the first place. i.e. No
such problem, so no need for biwiring as a 'solution'. No real problem
with the FFT, either. Nor indeed with mudane ideas like linear
superposition, etc. :-)

Shame if anyone though they were hearing what was claimed since the claimed
theory didn't stand up to either measurement or careful analysis based on
the physics involved according to the claimant's own descriptions.

None of which stopped the claimant from continuing to push his idea.

I wonder if any of that appeared in any USA printed mags?... Didn't appear
here in print so far as I know.

[snip]

Interesting how many people pooh-pooh equalizers, but rush to accept an
badly-designed "Bi-amp" equalizer implmented by what might be the most
expensive and non-adjustable means possible.

IIRC the use of biamping, biwiring, etc, all tended to only come into vogue
*after* the gurus decided that 'tone controls are baaaad' and makers saved
cash by stopped including them. No problem for them if the result was that
people bought more amplifiers. :-)

Personally I still like tone controls and balance controls to be avilable.
Although I appreciate them being designed to work well, and to be bypassed
if preferred. Much cheaper and more flexible than biamping IMHO.

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.audiomisc.co.uk/index.html
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html

Quad 606 with a Quad 405
 

MiNe 109 wrote:

Here's a bad idea: off-the-shelf
electronic crossover to replace a specific passive crossover.

The 'off-the-shelf' crossover I mentioned is accurate, high-order
and has adjustable delay. How can that be worse than a passive one?

--
Eiron.

Quad 606 with a Quad 405
 

"MiNe 109" wrote in message

In article ,
"Arny Krueger" wrote:

"MiNe 109" wrote in message

In article
, "Arny
Krueger" wrote:

"MiNe 109" wrote in
message


In article
,

"Arny Krueger" wrote:

Bi-amped has traditionally meant, and means in most
audio circles to this day, active crossover, two
power amps, two-way speaker system.

Hence the term 'passive bi-amping' to distinguish it
from your definition.

There's a whole forest of made-up terms out there for
this sort of weirdness:

vertical bi-amp

horizontal bi-amp

come to mind.

Those are different configurations of passive bi-amping.

A possible case for the passive method is as an
intermediate step for one who wishes to complete the
active system later.

Almost everything is possible in the world of
imagination. Doesn't make many of them anything like a
good idea.

This is one of the good ones.

For the sales guy!

The sales guy has to wait for the eventual purchase of
the active crossover.

Here's a bad idea:
off-the-shelf electronic crossover to replace a specific
passive crossover.

That might not be any worse than using two power amps
with mismatched gains, which is what the combination
that OP mentioned had. Yes, the OP had been told a tall
tale about matched gains, but the relevant facts told a
different story. The amps did not have matched gains.
There was more than enough gain difference to change the
basic sound of the Spendors.

That's too bad for him.

OTOH, traditional biamping is becoming a trend, as a
delivered complete engineered speaker/amp system, not a
random collection of parts thrown together by clueless
audiophile dupes and shyster sales hacks.

How are amps from the same maker said to have the same
gain a "random collection of parts"?

You're apparently not following the whole thread,
Stephen. Yes, the OP said that he was told that he had
two amps from the same maker that had the same gain.
When we looked at the relevant facts, we found that
someone had been telling him audio fairy stories. The
amps don't have matched gain, no matter what he was
told.

Perhaps you could suggest a way of matching gains.

In this case, the most sensible approach is to use just one amplifier.

Quad 606 with a Quad 405
 

"Eiron" wrote in message

MiNe 109 wrote:

Here's a bad idea: off-the-shelf
electronic crossover to replace a specific passive
crossover.

The 'off-the-shelf' crossover I mentioned is accurate,
high-order and has adjustable delay. How can that be
worse than a passive one?

A well-designed passive crossover also considers the response of the
drivers, possibly with additional compensating components, crossover points
and and filter Q's shifted to compensate for the drivers.

Quad 606 with a Quad 405
 

"Arny Krueger" wrote in message
...
"Bob Latham" wrote in message

In article ,
Arny Krueger wrote:
"Bob Latham" wrote in message


You are both correct from a simple electrical point of
view it is quite pointless. However, I might point out
that rightly or wrongly, probably a substantial majority
of people with an interest in Hi-Fi would say that
Bi-amped systems sound better

But this isn't really bi-amping. There are still passive
crossovers, and both amplifiers have to amplify the full
signal.

Its not "active" certainly but it is what most would mean
by bi-amped.

Who is this "most"?

Most audio fanatics?

Bi-amped has traditionally meant, and means in most audio circles to this
day, active crossover, two power amps, two-way speaker system.

That a few naive audiophiles have been snookered into buying two amps to a
job that one amp can do as well, is an aberration.


Arny, as this is a UK news group, we normally use UK nomenclature. This side
of the pond, using two amplifiers but retaining the passive crossover is
generally called "bi-amping" whilst using two amplifiers with electronic
crossovers is generally called "active". The former is of no value whilst
the latter provides many benefits.

S.

--
http://audiopages.googlepages.com

Quad 606 with a Quad 405
 

"Arny Krueger" wrote in message
...
"MiNe 109" wrote in message

In article ,
"Arny Krueger" wrote:

"MiNe 109" wrote in message


In article
,

"Arny Krueger" wrote:

Bi-amped has traditionally meant, and means in most
audio circles to this day, active crossover, two power
amps, two-way speaker system.

Hence the term 'passive bi-amping' to distinguish it
from your definition.

There's a whole forest of made-up terms out there for
this sort of weirdness:

vertical bi-amp

horizontal bi-amp

come to mind.

Those are different configurations of passive bi-amping.

A possible case for the passive method is as an
intermediate step for one who wishes to complete the
active system later.

Almost everything is possible in the world of
imagination. Doesn't make many of them anything like a
good idea.

This is one of the good ones.

For the sales guy!

Here's a bad idea:
off-the-shelf electronic crossover to replace a specific
passive crossover.

That might not be any worse than using two power amps with mismatched
gains, which is what the combination that OP mentioned had. Yes, the OP
had been told a tall tale about matched gains, but the relevant facts told
a different story. The amps did not have matched gains. There was more
than enough gain difference to change the basic sound of the Spendors.

OTOH, traditional biamping is becoming a trend, as a
delivered complete engineered speaker/amp system, not a
random collection of parts thrown together by clueless
audiophile dupes and shyster sales hacks.

How are amps from the same maker said to have the same
gain a "random collection of parts"?

You're apparently not following the whole thread, Stephen. Yes, the OP
said that he was told that he had two amps from the same maker that had
the same gain. When we looked at the relevant facts, we found that someone
had been telling him audio fairy stories. The amps don't have matched
gain, no matter what he was told.


The OP was told, apparantly erroneously, by QUAD that the amps had the same
gain. Consequently, they could be used for bi-amping. However, it turns out
that the amps don't have the same gain, but the same sensitivity for full
power, consequently they can't be used for bi-amping unless the more
sensitive (606) is padded down to match the less sensitive (405).

S.


--
http://audiopages.googlepages.com

Quad 606 with a Quad 405
 

"Serge Auckland" wrote in
message
"Arny Krueger" wrote in message
...

Yes, the OP said that he was told that he had
two amps from the same maker that had the same gain.
When we looked at the relevant facts, we found that
someone had been telling him audio fairy stories. The
amps don't have matched gain, no matter what he was
told.

The OP was told, apparantly erroneously, by QUAD that the
amps had the same gain. Consequently, they could be used
for bi-amping. However, it turns out that the amps don't
have the same gain, but the same sensitivity for full
power, consequently they can't be used for bi-amping
unless the more sensitive (606) is padded down to match
the less sensitive (405).

Agreed. What we were possibly seeing here was a stimulus for the creation
apparent support for yet another audio myth - the myth of passive
biamplification. Had the OP fallen for the erroneous advice he received, he
would have probably heard a difference due to the difference in the
amplifier gains.

Fortunately a little fact-checking nipped the potential damage done by the
erroneoua advice in the bud.

Quad 606 with a Quad 405
 

In article ,
MiNe 109 wrote:


Am I the only one who has actually used a multiple amp passive system?
In my case, Linn Kabers, a single LK100 was better than a Majik
integrated, but two LK100s weren't better than a single. Three with an
active crossover were a massive improvement.

A) What steps did you take to check if the frequency response was the same
in every case? e.g. did you ensure the gain levels were the same in each
case?

B) What steps did you take to ensure that your conclusions were based
solely on the actual biamping? e.g. not due to variations in your hearing,
or a slight movement in speaker locations, or a combination of various other
possible variables?

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.audiomisc.co.uk/index.html
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html

Quad 606 with a Quad 405
 

The most dramatic change I ever heard was in a shop when the removed the
Isobariks and tried Quad 63's. From awful to excellent. They shop droids
hated the Quads. But then they were unable to hear that one of the tweeters
in one of the Isobariks was busted... :-)


"Never in the field of domestic audio was so much bull**** dispensed by
so few and believed by so many"

With apologies to Winnie;)...
--
Tony Sayer