Is there a value in QUAD II amplifiers?
 

On Sun, 30 Sep 2007 14:32:31 +0300, "Iain Churches"
wrote:

http://www.saturn-sound.com/images/l...0amplifier.jpg

That's what I meant to post.

Thanks Don. Interesting link. Note both the Bulgin mains
socket and also the XLR (Cannon) speaker connector, which was
also at one stage used as a power connector. Neither are
approved these days.

Iain

Yes, my earliest valve designs for the Rank Organization used Bulgin
mains connectors. Video was done through Belling and Lee TV connectors
which were horribly unreliable. We eventually switched to those
screw-on PL259 UHF connectors that looked a little like N types from
outside.

d

--
Pearce Consulting
http://www.pearce.uk.com

Is there a value in QUAD II amplifiers?
 

"Don Pearce" wrote in message
...
On Sun, 30 Sep 2007 14:32:31 +0300, "Iain Churches"
wrote:

http://www.saturn-sound.com/images/l...0amplifier.jpg

That's what I meant to post.

Thanks Don. Interesting link. Note both the Bulgin mains
socket and also the XLR (Cannon) speaker connector, which was
also at one stage used as a power connector. Neither are
approved these days.

Iain

Yes, my earliest valve designs for the Rank Organization used Bulgin
mains connectors.

The large version of the Bulgin connector, the one shown in the
pic, was very common on broadcast and studio equipment, including
all the EMI TR and BTR series of tape machines. It is now no longer
approved except as an internal connector protected by a panel
attached by at least two screws. The small version is still available,
and rated at 70V.

So you worked for Rank, then Don? They took over Leak. Was
that before or after your time?

Iain

Is there a value in QUAD II amplifiers?
 

"Dave Plowman (News)" wrote in message
...
In article ,
Iain Churches wrote:
Can't remember the
identification they gave the Quad 50 in its various designations. The
BBC Leak amp still wore its Leak badge, though.

That is certainly so for the TL12, but the LSMs that I have seen
had no badge expect for the BBC engineering workshops plate
front left.

What colour where they?

They were battleship grey, with just the BBC engineering workshops
plate. I have always assumed that the gold versions were probably
from the Leak factory and the grey BBC ones built in-house.

The Leak amps I remember from my BBC TV days were
all Leak gold. BBC amps were all BBC grey - or whatever the contemporary
colour was.

But those Leak amps certainly had balanced inputs - I assumed
as supplied by Leak to special order.

I have just learned by e-mail that the LSMs were designed to
work with the BBC LSU/110 speaker. They were built into
the bottom of the speaker cab and had a 25 Ohm output
transformer. There were various versions, all balanced input,
with and without the input attenuator. Some also had a LF
equalizer.

I have been promised some pics.
Meanwhile, anyone interested in the original Leak TL12
can see an example of this beautifully constructed amp at:

http://www.kolumbus.fi/iain.churches/Pics/leaktl12.jpg


Of course later on they used Quad 405s for the LS5/8 which were specials
with crossovers built in - so it might make sense to remove badges to
avoid any confusion.

Indeed.

Iain

Is there a value in QUAD II amplifiers?
 

On Sun, 30 Sep 2007 17:16:02 +0300, "Iain Churches"
wrote:


"Don Pearce" wrote in message
...
On Sun, 30 Sep 2007 14:32:31 +0300, "Iain Churches"
wrote:

http://www.saturn-sound.com/images/l...0amplifier.jpg

That's what I meant to post.

Thanks Don. Interesting link. Note both the Bulgin mains
socket and also the XLR (Cannon) speaker connector, which was
also at one stage used as a power connector. Neither are
approved these days.

Iain

Yes, my earliest valve designs for the Rank Organization used Bulgin
mains connectors.

The large version of the Bulgin connector, the one shown in the
pic, was very common on broadcast and studio equipment, including
all the EMI TR and BTR series of tape machines. It is now no longer
approved except as an internal connector protected by a panel
attached by at least two screws. The small version is still available,
and rated at 70V.

So you worked for Rank, then Don? They took over Leak. Was
that before or after your time?

Iain


That happened well after I left them.

d

--
Pearce Consulting
http://www.pearce.uk.com

Is there a value in QUAD II amplifiers?
 

In article ,
Iain Churches wrote:
I have just learned by e-mail that the LSMs were designed to
work with the BBC LSU/110 speaker. They were built into
the bottom of the speaker cab and had a 25 Ohm output
transformer. There were various versions, all balanced input,
with and without the input attenuator. Some also had a LF
equalizer.

Think you mean LSU/10. Cabinet by Lockwood - before they became famous in
their own right as speaker assemblers.

I *think* there's some more confusion here. The LSU/10 used a dual
concentric unit by Parmeko with a Lorenz super tweeter added afterwards -
and I don't think ever had any equalisation offered. I'm pretty sure they
were the normal 15 ohm.

The later LS3/1 - designed for OBs and also as a foldback speaker (along
with the LSU/10) used a similar amp at first and IIRC that had some bass
EQ available - large driver in a small(ish) box. The LS3 continued for a
long time as a foldback speaker but was fitted with the Quad 50 later.

--
*I'm out of my mind, but feel free to leave a message.

Dave Plowman London SW
To e-mail, change noise into sound.

Is there a value in QUAD II amplifiers?
 

"Dave Plowman (News)" wrote in message
...
In article ,
Iain Churches wrote:

I have just learned by e-mail that the LSMs were designed to
work with the BBC LSU/110 speaker. They were built into
the bottom of the speaker cab and had a 25 Ohm output
transformer. There were various versions, all balanced input,
with and without the input attenuator. Some also had a LF
equalizer.

Think you mean LSU/10. Cabinet by Lockwood - before they became famous in
their own right as speaker assemblers.

Yes. Sorry. Typo on my part. LSU/10 with the shelf at the bottom.

I *think* there's some more confusion here. The LSU/10 used a dual
concentric unit by Parmeko with a Lorenz super tweeter added afterwards -
and I don't think ever had any equalisation offered. I'm pretty sure they
were the normal 15 ohm.

The EQ was on the amp, in addition to the input level control.
The LSU/10 was 25 Ohm, according to two BBC people who
contacted me about this. This may also solve the puzzle of an
early Radford which I have seen with a BBC plate. It too has
a 25 Ohm OPT.

Iain

Is there a value in QUAD II amplifiers?
 

"Don Pearce" wrote in message
...
On Sun, 30 Sep 2007 17:16:02 +0300, "Iain Churches"
wrote:

So you worked for Rank, then Don? They took over Leak. Was
that before or after your time?

Iain


That happened well after I left them.

Leak disappeared when the Man with the Gong came onto
the scene. Some ten years ago the tradmark was for sale,
at a quite modest price. It seems it has since been bought
by a Chinese venture capital company.

Iain

Is there a value in QUAD II amplifiers?
 

"Iain Churches" wrote in message
ti.fi...

"Don Pearce" wrote in message
...
On Sun, 30 Sep 2007 12:14:49 +0100, Laurence Payne
NOSPAMlpayne1ATdsl.pipex.com wrote:

On Sun, 30 Sep 2007 10:28:41 GMT, (Don Pearce)
wrote:

I found this

http://www.saturn-sound.com/

Fascinating stuff! But don't his overuse of inverted commas and
misplaces apostrophes grate after a time! You get a (doubtless quite
erronous) picture of an old-timer who is pedantic, meticulous but
WRONG :-)

Oops - meant to dig a little deeper for the link.

http://www.saturn-sound.com/images/l...0amplifier.jpg

That's what I meant to post.

Thanks Don. Interesting link. Note both the Bulgin mains
socket and also the XLR (Cannon) speaker connector, which was
also at one stage used as a power connector. Neither are
approved these days.

Iain


Only just noticed the BBC version of Leak Point One 'sub-thread'.
Hope it's not too late to point out.....You got those interfaces inverted...
that huge, Bulgin 2-p panel plug!!
fed a loudspeaker system, and the Cannon/Switchcraft "LNE" panel unitor was
for 240V mains input, both items IMHO stupidly implemented in mating pairs
the dangerous way round! Note the 1.25" fuseholder does not stipulate
replacement fuse rating!
Jim

Is there a value in QUAD II amplifiers?
 

On Mon, 01 Oct 2007 12:38:00 GMT, "jim Gregory"
wrote:


"Iain Churches" wrote in message
hti.fi...

"Don Pearce" wrote in message
...
On Sun, 30 Sep 2007 12:14:49 +0100, Laurence Payne
NOSPAMlpayne1ATdsl.pipex.com wrote:

On Sun, 30 Sep 2007 10:28:41 GMT, (Don Pearce)
wrote:

I found this

http://www.saturn-sound.com/

Fascinating stuff! But don't his overuse of inverted commas and
misplaces apostrophes grate after a time! You get a (doubtless quite
erronous) picture of an old-timer who is pedantic, meticulous but
WRONG :-)

Oops - meant to dig a little deeper for the link.

http://www.saturn-sound.com/images/l...0amplifier.jpg

That's what I meant to post.

Thanks Don. Interesting link. Note both the Bulgin mains
socket and also the XLR (Cannon) speaker connector, which was
also at one stage used as a power connector. Neither are
approved these days.

Iain


Only just noticed the BBC version of Leak Point One 'sub-thread'.
Hope it's not too late to point out.....You got those interfaces inverted...
that huge, Bulgin 2-p panel plug!!
fed a loudspeaker system, and the Cannon/Switchcraft "LNE" panel unitor was
for 240V mains input, both items IMHO stupidly implemented in mating pairs
the dangerous way round! Note the 1.25" fuseholder does not stipulate
replacement fuse rating!
Jim



Right. But looking closely, it appears that the mains input socket is
a replacement for something the same size as the Bulgin speaker
connector.

d

--
Pearce Consulting
http://www.pearce.uk.com

Is there a value in QUAD II amplifiers?
 

"jim Gregory" wrote in message
...

"Iain Churches" wrote in message
ti.fi...

"Don Pearce" wrote in message
...
On Sun, 30 Sep 2007 12:14:49 +0100, Laurence Payne
NOSPAMlpayne1ATdsl.pipex.com wrote:

On Sun, 30 Sep 2007 10:28:41 GMT, (Don Pearce)
wrote:

I found this

http://www.saturn-sound.com/

Fascinating stuff! But don't his overuse of inverted commas and
misplaces apostrophes grate after a time! You get a (doubtless quite
erronous) picture of an old-timer who is pedantic, meticulous but
WRONG :-)

Oops - meant to dig a little deeper for the link.

http://www.saturn-sound.com/images/l...0amplifier.jpg

That's what I meant to post.

Thanks Don. Interesting link. Note both the Bulgin mains
socket and also the XLR (Cannon) speaker connector, which was
also at one stage used as a power connector. Neither are
approved these days.

Iain


Only just noticed the BBC version of Leak Point One 'sub-thread'.
Hope it's not too late to point out.....You got those interfaces
inverted... that huge, Bulgin 2-p panel plug!!

Gosh. So it is:-) A 2-pin Bulgin.

fed a loudspeaker system, and the Cannon/Switchcraft "LNE" panel unitor
was for 240V mains input, both items IMHO stupidly implemented in mating
pairs the dangerous way round! Note the 1.25" fuseholder does not
stipulate replacement fuse rating!
Jim