rogers Ls3/4C

[greyhound]

http://www.uploadgeek.nl/files/00pisflkq15yuj5ezdzf_thumb.jpg (http://www.uploadgeek.nl/viewer.php?file=00pisflkq15yuj5ezdzf.jpg)

this is how i found them.
just lying there on the floor.


http://www.uploadgeek.nl/files/mhpw180nehsph450p9lm_thumb.jpg (http://www.uploadgeek.nl/viewer.php?file=mhpw180nehsph450p9lm.jpg)

now there upright and playing beautifullly.
the mid section is realy open. lots of information.
they go as deep as my century golds.
totally different character

more laid back, relaxed.
the century is more hifi and upfront.

now im gonna mod them a little. offcourse keep the original parts.
there are just forty pairs made for the BBC in the 70's
8" bexetrene woofer Ls2/13
audax tweeter Ls2/12

my century's are stored in the attic

[demon]

hello greyhound!

congratulations on these nice monitors. i found this page: http://www.mhennessy3.f9.co.uk/rogers/others.htm
containing this text: http://www.mhennessy3.f9.co.uk/rogers/bbc_txt.htm
containing this info:


...Yesterday's monitors...

LS3/1
A grey-painted totally-enclosed assembly for OB use. HF units were mounted on a perforated sub-baffle in front of the lf unit, to enable accurate monitoring at close range.
The following units were used:
- Plessey 15-inch paper cone woofer
- 2 x Rola-Celestion HF1300 tweeters

LS3/1A
Similar to the L53/1 but with the bass unit replaced by a Goodmans C129/15pr.

LS3/4, and B
An angled-front assembly for mounting close to the ceiling where space was at a premium, eg. OB vehicles or above vt machines. Beware! Some of these are still in service but the surround of the bass unit fails with age and the unit is obsolete. The old ones have a gold coloured grille cloth. There are later, current types, with a black grille and the old may be modified into the new (see LS3/4C and LS5/11 on the next page, under "Today's monitors").
The following units were used:
- Spendor BC2/8, 203mm Bextrene cone woofer
- Rola-Celestion HF1300 tweeter

LS3/5
The predecessor to the L53/5A. Superseded when the particular bass unit used became unreliable.
The following units were used:
- KEF B 11O, 1 l Omm Bextrene cone woofer
- KEF T27 27mm Mylar dome tweeter
LS3/7
Similar in size to the LS3/ 1 and designed to replace it. Some are still in service for talkback, but none should now be used for monitoring. Max SPL at 1.5m: 104dB(A). Will become obsolete when repair stocks of drive units are exhausted.
The following units were used:
- Spendor 8-inch Bextrene cone woofer
- Son Audax HD 12x9D25, 25mm fabric dome tweeter
The amplifier (AM8/15) is a modified Quad 303 where one channel drives the if and one the hf, by the use of an electronic frequency-splitting and equalising network.
as well as:


...Today's monitors...

LS3/4C
A medium sized triangular-shaped assembly, for mounting on a ceiling or wall where space is at a premium. Used in television in CMCRs/ MCRs or vt cubicles. Replaces the L53/4 and LS3/4B, or may have been converted from one of the above. Max SPL at 1.5m: 101dB(A). About forty are in BBC service.
The following units are used:
- 8-inch Bextrene cone woofer (LS2/13)
- Son Audax HD 13D34, 34mm fabric dome tweeter (LS2/12)
Requires a 50 watt amplifier.

LS3/SA
A small `bookshelf' assembly for use in restricted areas, such as OB vehicles. Extensively used in Local Radio. Max SPL from a pair at 1.5m: 95dB(A). Over 3500 are in BBC service and over 100,000 have been sold commercially, worldwide. Made under licence by Swisstone (Rogers), Spendor and Harbeth.
The following units are used:
- KEF B 110 SP1228, 1 l 0mm Bextrene cone woofer.
- Modified KEF T27 SP1032, 27mm Mylar dome tweeter.
- KEF SP2128 crossover (FL6/38)
Requires a 25 watt amplifier.

have fun--
mikey

[mech986]

Hi, nice find. Do you have additional photos showing closeup of the driver fronts and possibly of them pulled from the cabinets showing the backs? Sometimes one can then determine which specific drivers were used by Rogers as they used commercially available drivers for many of their speakers.

Also, do you have a pic of any labels on the back from Rogers or the BBC? Are they typical BBC XLR inputs? Did you also have the grilles?

These speakers could have been made either for corner use or for ceiling mount. Unlikely used as a floor monitor since they have limited power handling capacity.

Regards,

Bart

[mech986]

Here are links to the predecessor LS3/4 and LS3/4B models:

http://www.bbceng.info/EDI%20Sheets/10054.pdf

http://www.bbceng.info/EDI%20Sheets/10054_2.pdf

and the LS3/6 upon which it was based. The LS3/6 was a Rogers Design which eventually evolved into the Spendor BC-1 and the Rogers Export Monitor/Studio 1 designs, each moving from a 2-way to a 3-way.

http://www.bbceng.info/EDI%20Sheets/10056.pdf

Hope this helps.

Bart
Yahoo! LS3/5a Newsgroup Moderator

[greyhound]

http://www.uploadgeek.nl/files/jsjxmfmvajclwwobdxm3_thumb.jpg (http://www.uploadgeek.nl/viewer.php?file=jsjxmfmvajclwwobdxm3.jpg)


http://www.uploadgeek.nl/files/m7dg6lmsmj0az2boh5ww_thumb.jpg (http://www.uploadgeek.nl/viewer.php?file=m7dg6lmsmj0az2boh5ww.jpg)

didnt make any pics yet of the drivers. but i opened them up and the drivers of the Ls3/4C are there.

the old bextrene woofer stiffened with age. the C model has a beteter driver.
they have been reconed , i can see that. momnet i got them here they didnt open up in terms of sound but the temperature in my house and a little silliconespray on a dry cloth (rub the rubber edges of the cone)
did the trick.


just got a phone call my stephmother past away.
so im thank you all for your contributions.

[greyhound]

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