Bacelonas Cleveland

[GM]

But they thought since they owned the theater market they did not need to improve.

JBL courted Lucas. In the early days a system could not THX spec without a 2 inch driver.

OK, not the vibes I got from the local distributor, but they tended to be a 'law unto themselves' since the cost of THX theater certification was too much, so AFAIK there was ever only one in the greater metro Atlanta area and don't recall it staying in business all that long.

Don't recall anyone mentioning a THX 2" min. driver spec, but certainly fills in a lot of blanks to explain some other stuff re the ill conceived 511E, 9848 monitor and A9 cinema speakers that went nowhere.

Today, as big, populous as we are now, there's only three 70 mm Dolby cinemas AFAIK, with a few others that do temporary installs for the big blockbuster movies, so all things considered, THX, Dolby certification still isn't a big deal to the paying public.

GM

[Old Guy]

So were the JBL THX rated systems a 3 way setup?

I don't remember. I never worked in theater, always SR. UPDATE: All a quick google tuned up was early THX used stacked tweeters. I would assume the ring jobs.

- - - Updated - - -

OK, not the vibes I got from the local distributor, but they tended to be a 'law unto themselves' since the cost of THX theater certification was too much, so AFAIK there was ever only one in the greater metro Atlanta area and don't recall it staying in business all that long.

Don't recall anyone mentioning a THX 2" min. driver spec, but certainly fills in a lot of blanks to explain some other stuff re the ill conceived 511E, 9848 monitor and A9 cinema speakers that went nowhere.

Today, as big, populous as we are now, there's only three 70 mm Dolby cinemas AFAIK, with a few others that do temporary installs for the big blockbuster movies, so all things considered, THX, Dolby certification still isn't a big deal to the paying public.

GM

THX was the reason the EV DH1 came into existence. It's a DH1012/Altec 906 with a snout cast on to make it a 2 inch driver.

[lokie]

the 288 is, IMO, the perfect HF driver. It has most of the HF of a 802/902, with killer mids also.

How high can you get out of a 288 variant? I always thought 8khz was it's limit. Am I missing something?

[GM]

From a purely driver design POV, the 1" drivers are good to ~5500 Hz, the 1.4" to ~3500 Hz, rolling off for another octave [~11 kHz/7 kHz], so while one can use CD horn EQ to take them out to 15-20 Khz, much of it is technically just noise due to diaphragm break-up, surround resonances, horn reflections.

Our hearing acuity above ~5 kHz rapidly decays though, so basically their usable upper limit is a personal choice normally based on it broadband high SQ power limit.

GM

[Elitopus1]

How high can you get out of a 288 variant? I always thought 8khz was it's limit. Am I missing something?

GM is correct about the specs.

I think you just have to listen, and see if you like them or not. Some people need an additional tweeter.
I find them very satisfying to listen to without