Bi-amping - How do I rewire LS3/5A Speakers.??
lawrie
These are old Chartwell 15 ohm type, with just a pair of very small
screw terminals on the rear.
Does anybody have the wiring diagram for the original LS3/5A crossover, and
better still, can anyone tell me how to re-wire the speaker and cross-over
for bi-amping.
I plan to use either Quad 303 or 405-2 amps, as I have a pair of each
available at the moment to play with. Are these OK, or does anyone recommend
anything better.??
Any advice welcome.
thanks.
Lawrie.
Stewart Pinkerton
>I would like to bi-amp an old pair of LS3/5A speakers.
Why?
--
Stewart Pinkerton | Music is art, audio is engineering
lawrie
allow for biamping, by just removing the connector strip between on the
back. BUT I dont know if this was home mod, or manufacturers mod.
Was assured it makes "one hell of a difference" to the sound
quality (seperation and ambiance, - not my words) when you biamp.
I have the amps available to try it, and also another pair of LS3/5A to use
as a reference.
So, why not.??
Can anyone help or advise.?
Thanks.
Lawrie.
Stewart Pinkerton <pat...@popmail.dircon.co.uk> wrote in message
news:378c3b86...@news.dircon.co.uk...
Stewart Pinkerton
>I have seen newer LS3/5A speakers with two sets of terminal posts that
>allow for biamping, by just removing the connector strip between on the
>back. BUT I dont know if this was home mod, or manufacturers mod.
>Was assured it makes "one hell of a difference" to the sound
>quality (seperation and ambiance, - not my words) when you biamp.
>I have the amps available to try it, and also another pair of LS3/5A to use
>as a reference.
>So, why not.??
I guess it can't actually do any harm, but I have *never* heard
bi-wiring produce an improvement when checked under blind conditions,
and there's no reason why it should.
Mark A
>
> I guess it can't actually do any harm, but I have *never* heard
> bi-wiring produce an improvement when checked under blind conditions,
> and there's no reason why it should.
I think it's probably true that an awful lot of the esoterica, that's
raved about in the HiFi press, produces zero difference in true blind
tests. People tend to hear what they want to hear.
But then I'm a bit cynical like that anyway. :)
Regards
Mark
John Chapple
<pat...@popmail.dircon.co.uk> writes
>"lawrie" <law...@btinternet.com> writes:
>
>>I would like to bi-amp an old pair of LS3/5A speakers.
>
>Why?
Yes quite agree this was a carefully designed loudspeaker & I don't
believe in bi-amping in any case
--
John Chapple
John Woodgate
inimitably wrote:
>I have seen newer LS3/5A speakers with two sets of terminal posts that
>allow for biamping, by just removing the connector strip between on the
>back. BUT I dont know if this was home mod, or manufacturers mod.
>Was assured it makes "one hell of a difference" to the sound
>quality (seperation and ambiance, - not my words) when you biamp.
>I have the amps available to try it, and also another pair of LS3/5A to use
>as a reference.
>So, why not.??
The 'hell of a difference' is almost certainly due to the fact that the
biamped units don't have the same level balance between woofer and
tweeter as the originals.
--
Regards, John Woodgate, OOO - Own Opinions Only.
Phone +44 (0)1268 747839 Fax +44 (0)1268 777124.
Did you hear about the hungry genetic engineer who made a pig of himself?
PLEASE DO ****NOT**** MAIL COPIES OF NEWSGROUP POSTS TO ME!!!!
Peter Clinch
> The 'hell of a difference' is almost certainly due to the fact that the
> biamped units don't have the same level balance between woofer and
> tweeter as the originals.
Yes, note that "difference" is not the same as "improvement"... So why
does almost everyone these days have bi-amping terminals on speakers?
Because the market demands it, is my cynical answer. Just like Michael
Bolton records, market demand doesn't mean it's something people are
better off listening to (unless you have shares in cable/power amp
companies, that is).
Pete.
--
Peter Clinch University of Dundee
Tel 44 1382 660111 ext. 33637 Medical Physics, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net p.j.c...@dundee.ac.uk http://www.dundee.ac.uk/~pjclinch/
Allen Hutcheson
My first experience of bi-amping/bi-wiring was immediately after listening
to an Arcam Alpha 8R for 2 hours it was hooked up to the Arcam 8P power amp
- treble driven by pwr amp in one and bass by pwr amp in other - and it
made no audible difference to me whatsoever. Maybe I was expecting too much
?
Regards
Allen
Mark A wrote:
--
Allen W Hutcheson
Nomura International PLC
1 St Martins-le-grand
London
John Woodgate
There are perfectly good objective reasons why *bi-amping* can give
better performance, notably if it is used with low-level crossovers. (It
is especially advantageous with valve/tube amplifiers - less opportunity
for intermodulation distortion). But it is tricky to set the amplifier
gains so that the woofer and tweeter levels are exactly the same as in
an unmodified loudspeaker, for comparison purposes.
But SP has not noticed that 'Lawrie' asked about bi-amping, not bi-
wiring, which is very effective in increasing sales of ridiculously
costly cables, but has no objective basis.
Paul Whatton
>allow for biamping, by just removing the connector strip between on the
>back. BUT I dont know if this was home mod, or manufacturers mod.
>Was assured it makes "one hell of a difference" to the sound
>quality (seperation and ambiance, - not my words) when you biamp.
>I have the amps available to try it, and also another pair of LS3/5A to use
>as a reference.
>So, why not.??
>Can anyone help or advise.?
>Lawrie.
Hi (again) Lawrie
I will email you the circuit diagram of the LS3/5a crossover FL6/23.
The circuit does indeed lend itself very easily to bi-amping or bi-wiring,
the HPF and LPF sections can be easily seperated.
I have not tried either bi-wiring or bi-amping myself but since you have two
pairs you might like to try stacking them. Early LS3/5as were 15 ohm and so a
pair in parallel provide an easy load for the amplifier and a little extra
SPL (but no improvement in LF response) at the expense of high frequency
vertical beaming.
Incidentally I have tried stacking my 3 pairs, after all if you can
stack Quads why not 3/5as!
Regards
Paul
John Chapple
<j...@jmwa.demon.co.uk> writes
><JjwgfJA6...@ch-w.demon.co.uk>, John Chapple <j...@ch-w.demon.co.uk>
>inimitably wrote:
>>In article <378c3b86...@news.dircon.co.uk>, Stewart Pinkerton
>><pat...@popmail.dircon.co.uk> writes
>>>"lawrie" <law...@btinternet.com> writes:
>>>
>>>>I would like to bi-amp an old pair of LS3/5A speakers.
>>>
>>>Why?
>>
>>Yes quite agree this was a carefully designed loudspeaker & I don't
>>believe in bi-amping in any case
>
>There are perfectly good objective reasons why *bi-amping* can give
>better performance, notably if it is used with low-level crossovers. (It
>is especially advantageous with valve/tube amplifiers - less opportunity
>for intermodulation distortion). But it is tricky to set the amplifier
>gains so that the woofer and tweeter levels are exactly the same as in
>an unmodified loudspeaker, for comparison purposes.
well can an electronic crossover simulate this?
Not being an expert I appreciate (a little) the theorical point about
intermodulation distortion.
>
>But SP has not noticed that 'Lawrie' asked about bi-amping, not bi-
>wiring, which is very effective in increasing sales of ridiculously
>costly cables, but has no objective basis.
--
John Chapple
John Woodgate
inimitably wrote:
>Well (IIRC) the crossover for the LS3/5A was especially complicated. How
>well can an electronic crossover simulate this?
I was speaking in general about advantages of bi-amping. But, for
example, it is easy to accommodate differences in basic sensitivity
between woofer and tweeter by a simple gain tweak, whereas the passive
network really requires an auto-transformer, especially if it's the
woofer that's more sensitive.
John Chapple
<j...@jmwa.demon.co.uk> writes
><BkGy9CAv...@ch-w.demon.co.uk>, John Chapple <j...@ch-w.demon.co.uk>
>inimitably wrote:
>>Well (IIRC) the crossover for the LS3/5A was especially complicated. How
>>well can an electronic crossover simulate this?
>
>I was speaking in general about advantages of bi-amping. But, for
>example, it is easy to accommodate differences in basic sensitivity
>between woofer and tweeter by a simple gain tweak, whereas the passive
>network really requires an auto-transformer, especially if it's the
>woofer that's more sensitive.
The differences in sensitivity I can understand, but how with biamping
do you accomodate (for instance) a rising or falling sensitivity of a
particular loudspeaker unit or a notchy response?.
Things that the loudspeaker designer solves with an anecoic chamber &
(nowadays) a computer & a certain amount of art; & effects with a
passive crossover
--
John Chapple
Anahata
j...@ch-w.demon.co.uk "John Chapple" writes:
> The differences in sensitivity I can understand, but how with biamping
> do you accomodate (for instance) a rising or falling sensitivity of a
> particular loudspeaker unit or a notchy response?.
> Things that the loudspeaker designer solves with an anecoic chamber &
> (nowadays) a computer & a certain amount of art; & effects with a
> passive crossover
>
As I see it, there are three levels of sophistication in a passive
crossover:
1. the basic high pass and low pass filter function assuming resistive
loads
2. adjusting the component values to account for the fact that drivers
are not resistive
3. Compensating for frequency response irregularities in the driver
response itself.
A simple active crossover deals with (1) and (2) above, which solves
most of the problems
You are talking about (3) which is a fine tuning measure and can be done
in the same way, but then the active crossover is designed to work with
a particular set of drivers. This is of course, what happens in active
speakers, which explains why they can work so well.
--
Anahata
ana...@freereed.demon.co.uk http://www.freereed.demon.co.uk/
ana...@locust.co.uk (1st 8 lines sent as text message to mobile phone)
phone 0171 229 6076 home, 0171 638 5577 work, 0976 263827 Orange mobile
John Woodgate
inimitably wrote:
>The differences in sensitivity I can understand, but how with biamping
>do you accomodate (for instance) a rising or falling sensitivity of a
>particular loudspeaker unit or a notchy response?.
>Things that the loudspeaker designer solves with an anecoic chamber &
>(nowadays) a computer & a certain amount of art; & effects with a
>passive crossover
You either retain the passive crossover (splitting it into two paths at
the loudspeaker input terminals) or replace it by a low-level crossover
with the right responses. To do the latter, you need acoustic test
equipment. Not practical at home!
John Woodgate
<Ana...@freereed.demon.co.uk> inimitably wrote:
>A simple active crossover deals with (1) and (2) above, which solves
>most of the problems
If you believe that, you will believe in many things.