2035H opinions

[DS-21]

What's the general opinion of the 2035H? Would a single one per side be a good bottom end for an 8" high-efficiency coax, to be used from 60Hz until ~400Hz (sub crossover is 60Hz, because of room issues more than anything, and the upper crossover will be determined by listening and measuring) and fed a steady diet of Mahler, Shostakovich, and Bruckner in a medium-sized room?

While I've never used any JBL driver, by the numbers the 2035H's seem like nice drivers: Lambda Acoustics-like .25mH inductance, copper sleeve motor, 7mm, 98dB/w/m sensitivity, and a nice F3 for a main speaker in a reasonably-sized box. (For aesthetic reasons I had wanted something narrower than a 15, but there are virtues to 600cc displacement, too...) But searching didn't turn up much information about them beyond the snippets and graphs on the JBL product pages for some cinema systems.

[Robh3606]

I used them over the same range and they were fine. They sounded very good and can get down to 40Hz with no problems.


Rob

[DS-21]

What kind of box were you using to get 40Hz output? While I haven't done any serious modeling, my rudimentary sims thus far have told me that their effective F3 sealed is around 100Hz and ported is around 60.

Also, I note that you wrote "used" rather than the present tense. Is there another driver I should be looking at instead of the 2035H?

[johnaec]

Does the 2035H have a 3" or 4" voice coil? I know many of the 20xx speakers use a 3" voice coil.

John

[Robh3606]

I used them in 5 cuft. ported. as my mains with subs under them. They have a 3 inch coil. I used them mainly before I went active. Once I went active I started swapping out drivers. I use E145-8 now. I changed out the 2035's after I changed out my mids to 2123's. I felt the E-145,2123,2344 was the sound I was looking for and the drivers worked very well together. The E-145 is a unique bass driver not a general purpose 15 and has excellent clarity and dynamics. I like a very quick dynamic sound with no overhang and that combo was the best with the drivers that I tried IMHO.



Should you be looking at another driver??? Hard to say I don’t know what your looking for. There is nothing wrong with the 2035. It is an excellent general purpose 15 I just liked the E-145 better for my application. You could look at a 2234 as an alternative. Basically a 2235 without the mass ring. That's another 15 that could do the job very well and keep the efficiency up at 96db. You doing active or passive crossovers?? Do you need a 98db woofer???



Rob

[Robh3606]

Look here for more info

http://www.jblpro.com/pub/cinema/4638.pdf

Give distortion and what not

http://www.jblpro.com/pub/cinema/3677.pdf

You can run them safely up to 1.2K
Rob

[DS-21]

Should you be looking at another driver??? Hard to say I don’t know what your looking for.

Basically, I'm looking for midbass support for an 8" coax (Tannoy 2046, used in their System 800 monitor and CMS8 in-wall) in a system that will be used for all types of music but must especially sound good on balls-to-the-wall orchestral stuff such as well-recorded Shostakovich, Mahler, Sibelius, etc. (Though they will be connected to HT electronics, all the serious listening will be music.) I'll be doing a passive crossover within the mains, but of course going active to the remotely-located subs.

In 5 cubes tuned low, I can see getting in-room response to 40Hz with these things. I'll have to play some more with the models - and do some mock-ups to see how large my mains are allowed to get - to see what the sweet spot for me will be.

I figure a 98dB/w/m midbass will give me a total sensitivity in the 92-93dB/w/m range after considering crossover insertion losses, baffle step compensation, and bandpass gain on the woofer section of the coax. That said, I don't need 98dB/w/m; I'm not running flea-powered amps so if I have to pad the coax down a bit and use less-sensitive drivers I won't really lose anything. However, I expect now that I'll start with the 2035H and see where my system goes from there. Thanks for your help!

PS: The graphs on the 4638 page tell me that for hi-fi use these woofers are much happier being used only up to 300-400Hz or so, and that with fairly steep filters. That's fine for me, though it also tells me that should I ever ditch the coax approach for a Geddes-style horn crossed in where the woofer's directivity matches the horns I'll need a different woofer.