Crossover for JBL 2245h

[ITcity]

Hello,
can I use JBL 5234 for JBL 2245h
http://www.jblpro.com/pub/obsolete/5234a.pdf
If I just use 2245h as woofer, do I have to install crossover cards into JBL 5234? Now my 5234 is using 800hz Crossover, (18db Per Octave) Cards, do I have to change it?
Many thanks!

[pos]

Hi,
800Hz is really high for a 2245H, even for SR use.
500Hz seems to be the maximum most people would accept, and even 300Hz for home use (as in the 4345)
What are you using above these 2245?

[ITcity]

Many thanks,
I just want to improve Bass for my :
Altec 416A - 16ohm in Onken 360, 802D - 16ohm, horn 511B, N500F crossover, drive by pairs of Altec 1570B amplifier.
I intend to build 2 woofer cabinets with JBL 2245h, connect to LF of JBL 5234 crossover.
Is that correct or any better solution?
Thanks!

[grumpy]

If you want to use the 5234A with stock crossover cards, I'd start looking for some of
the 80Hz variety (51-5138). Depending on the bass rolloff of your system and your
personal preferences, you may be better off with a different frequency and slope,
and letting the onken cabinet run full range (just bringing up the 2245's to fill in the
bottom octave).

If you can find or borrow an adjustable crossover to experiment with,
you might get better focus on what works for you and your room/system.

[speakerdave]

grumpy pretty much says it.

The 80Hz cards are going to be a little difficult to find. If you look at the manual for the 5234A you will find instructions for loading 12 dB cards for 50, 70 and 100 Hz crossovers and 80 Hz high pass only and 100 Hz crossover 18 dB cards. I think I have some 80 Hz 18dB crossover cards at home, and if you'd like I could read you the loads for that. You could convert your 800 Hz cards.

Running the present system full range and feathering in the subwoofer is a nice idea, and is the one I prefer in many situations, but I think it would not be easy with your present set up unless you are prepared to move speakers around and do some testing. The room modes and two bass reflex systems to balance just may drive a person crazy.

The manual for the 5234A (and many others) may be downloaded at JBL PRO> Support>Service>Support/Information>JBL/UREI Electronics

[grumpy]

http://www.jblproservice.com/pdf/Vintage%20JBL-UREI%20Electronics/JBL-5235%20manual.pdf

5235 manual has the component listings (note that it's a ~4MB+ download)

[ITcity]

Thanks for your explanations,
after long long time waiting, luckily I've just won JBL 5234A with 80hz card on ebay:
http://cgi.ebay.com/JBL-FREQUENCY-DIVIDING-NETWORK-5234A_W0QQitemZ390036461152QQcmdZViewItemQQptZLH_D efaultDomain_0?hash=item390036461152&_trksid=p3286.c0.m14&_trkparms=66%3A3|65%3A1|39%3A1|240%3A1318

I have pair of 2245H new, can I build two JBL B460 and use my 80 hz 5234A crossover for it? each chanel for one B460?

[speakerdave]

Thanks for your explanations,
after long long time waiting, luckily I've just won JBL 5234A with 80hz card on ebay: . . . . I have pair of 2245H new, can I build two JBL B460 and use my 80 hz 5234A crossover for it? each chanel for one B460?

Yeah, I saw that right after you started that thread and thought of you. . . . . Synchronicities enough to delight any Jungian. Good score, anyway.

Do some searches here for 2245 and B460, and I believe somewhere you will come across some suggestion about using the built in bump and high pass possibilities in the 5234A. Also, read the manual.

You can feed the 5234 with stereo signals and run one LP output to each sub amp. Is that your question?