Graham LS5/9

[f1eng]

LS5/8 and LS5/9 are both standard BBC designations.
The basic design is a given and there is not much variance permitted by the BBC if the manufacturer wishes to use the designation and be licensed.
The BBC require them to sound the same as each other so any LS5/8 or LS5/9 (or LS3/5a) can be dropped in as a replacement for any other if one gets damaged, for example.
Mind you, I don't know how many are still in use at the beeb 30 years after they first came into service.
Derek Hughes said in the interview that he specified the 8" unit and that his intention was to produce the LS5/9 sound without the unit suffering the deterioration heard in the existing old units out there.
The LS5/8 does have a 12" bass unit.

Edit: some info, though I can't vouch for its accuracy it is, after all, on an internet site
http://www.markhennessy.co.uk/rogers/ls58.htm

another edit, Harbeth actually state that the Monitor 30 is a "refinement" of the LS5/9. Certainly all Harbeths have been designed using the BBC design philosophy since day 1 as Dudley Harwood was a senior engineer at the BBC and was instrumental in coming up with the cabinet philosophy used by all the LS speakers since and experimented with cone materials.

Frank,

In your first post you mention that the Graham LS5/9 has a 12" woofer (or was it a misspelling?) however as you say now it has a 8" hence I stated this.

To my ears the Graham LS5/9 is a refinement of the Harbeth 30.1 sound output despite that the Graham version is licensed and has to stick to the original construction. Though as I understand from the interview is that Graham made some refinements too.

A 12" bass unit on the LS5/8 should on paper including the more than 3 times bigger box be able to output both more as deeper bass,

Our listening room is about 30 m2 so I guess it could take the bigger LS5/8.

I will for sure have a go with the LS5/8 in my home before making a commitment to buy.

/Mike

Yes Mike,
I got confused with my BBC nomenclature, sorry! It is the LS5/8 which has the 12" main unit. Indeed it should produce more bass, the problem has always been the beaming of the mid range and up to crossover frequencies of such a large main unit and integrating the step to the tweeter.
I have never heard a LS5/8 but have had Harbeth active Monitor 40s here on loan from their owner. His other pair sounded absolutely fabulous in a different room but here I have been unable to find a location where the bass is not bloated and tubby sounding, unfortunately. They are extremely room position sensitive.
I haven't heard either the Harbeth M30 or the Graham, just the Rogers LS5/9 decades ago.