2225 enclosure

[hector.murray]

I'm getting ready to build a 2225 cabinet with a pair of 2225Hs'. Reading the JBL PROFESSIONAL ENCLOSURE GUIDE here http://www.jblpro.com/pub/manuals/enclgde.pdf I'm a little unsure of the number of ports to use. The way I'm reading it, I believe I need to use a total of four 4" dia x 5" length ports. Is this correct?

[Zilch]

That's how I read it, yes, for an 8 cu.ft. enclosure....

WinISD says you want a 3.596 cu.ft. box tuned to 58.12 Hz with two 4" ports 2.5" long for optimum. That sucks. Lemme try again. :D

8 cu.ft. tuned to 40 Hz wants four 4" ports 7.5" long, or two of them 2.3" long.

10 cu.ft. tuned to 40 Hz wants four 4" ports 5.375" long.

I'd be modeling on the SR or SRX series dual 15 subs, probably, which have two 2226's in them. JBL already did the figuring for you.

Discretely measure port dimensions at Guitar Center....

[hector.murray]

I got the same numbers in WinIsd as you did.

[Dave G]

I would expect longer ports would lower the tuning well below 40 as I found win isd to be inaccuarate compared to actual test box using JBL guide. I'm using 2226 which is similar woofer parameters to 2225.

Of course the volume of the JBL box has taken in to account .2 cu ft woofer displacement per woofer and port dispalcement of volume. Fraction over 4 cu ft of actual volume with my single woofer box.

SRX dimensions and port arrangment are welcome:) it uses very tidy central slot port. The SR mk 1 is not very special, you could build better box from JBL guide.

[paragon]

A Dual Reflex for the older 2205A Driver i build in the mid 80`s and had them for many years in my living room. Pics are bad, sorry.

[spkrman57]

How would you characterize the sound from a pair of 2205A's in that cabinet. I have a pair of 2205A's also and found them to sound best in a large sealed cabinet. With a ported cabinet, I detected a muffled boominess in mine.

Once I sealed the ports, the boominess went away.

Ron

[hector.murray]

I live in the sticks. Finding a guitar center that handles JBL is a 3 or 4 hour run, depending on whether I go south or west.
I'm thinking about how this thing is going to get lugged around. I think it's gonna get wheels, otherwise I'm going to become a roady for my 13 yo son who is going to be the recipient of this thing.
You shoulda seen his response yesterday when the mailman delivered it. :bouncy:
Well, I'm off to the garage to cut some plywood.
Thanks everyone.

[paragon]

Hi Speakerman,

Sound was good (remember), speakers standing in the edge (corner?), response going to 40 Hz down and they where louder than my 4530 (of course 4 Ohms !!).
Loved this speakers, but we got new furniture and there was no place for this big ones. So i changed to a pair L90 with a big Bandpass sub (with two 2205A).
In my "music room" is still playing the old 4530 (copy).

Eckhard

[spkrman57]

If the sound might have changed much.

My 2205A's(not original owner-so don't know if they demagnetized or not) did not do well in 4 cu ft enclosure with dual ports(6 cubic ft). The sound was a muffled boominess.

I stuffed the ports until they did next to nothing and the 2205A's came to life with really great bottom end.

I have them in my 80 hz midbass horns(Edgar) and I am not impressed with them as they don't seem to have much efficiency.

Now that I have Mike's E-130's reconed to 2225's, I will try them in the midbass horn and see if the results are the same as the 2205A's.

Ron

[paragon]

Try as you want.
My 2205 (self bought) running very well in reflex an horn enclosure.

[spkrman57]

I got them a few years back through the connections of several folks. So I am unaware of the magnet strenth.

Mike's 2225's are ferrite and similiar spec's wise. I might have to try them out this week if I find the time.

Ron

[jbl]

Hector,
Do what I did, you won't go wrong. Check the Library for the 4507 cabinet. I have them. With the 2225H, they sound great. The 4507 uses 4 ports. Don't use a smaller cabinet than 5ft3.

Ron

[Zilch]

Yup. 4507. I forgot about those. Another good model. The design work's been done.... :)

[Richard Long]

hi,

a friend want to work with one 2225h down to 30hz. what enclosure dimension he need ?

[speakerdave]

That dog won't hunt.

He COULD rip the 2225 cones out and have 2235's installed, but then he probably paid for working woofers, and the changeover would be expensive. JBL savvy Forum member Guido is in Germany. Send him a PM; he can help.

David

[jbl]

That dog won't hunt.

He COULD rip the 2225 cones out and have 2235's installed, but then he probably paid for working woofers, and the changeover would be expensive. JBL savvy Forum member Guido is in Germany. Send him a PM; he can help.

David
Don't destroy the 2225!
I bought brand new pair of 2235H rather than destroy the 2225H by reconing them. I bought the 2225H new in 1985. Never overdriven. If you have a questionable pair of woofers, make certain that the magnet hasn't shifted before reconing.
The voicing between 2225H and 2235H are the same in the midrange. The 4 dB difference isn't a factor with my system. At first, I was concerned that I would have to pad down the 2425/2370. Not necessary.
The difference is the extended LF as well as higher output at the low end of the 2235H.
The 2225H works well in a 5 ft3 cabinet, so consider that. You can use the 2235H as a sub.
The combination makes for a very versitile future or present system.
With the 4507, for example, the cabinet could be tuned to 40Hz for use with the 2225H, or for 35Hz, using 3 ports, or for 30Hz using 2 ports with the 2235H. In addition, the 2225H can be used with the 4507 (40Hz as intended) along with a sub woofer system using the 2235H. Four different combinations. Can't beat that!
Just my thinking when I bought the 2235H. Yes, it was expensive to get the 2235H, but they were new from JBL. Still a better investment since I keep the 2225H as well.

Ron