BX63A better than BX63?

[pmakres1]

I recently inherited another 18" JBL sub, utilizing a 2241 driver in a roughly 8 cubic foot enclosure. It sounds nearly identical to my B460 sub. Along with it I was given a very nice BX63A crossover. I pulled my basic BX63 unit from my main system, and replaced it with the newly acquired BX63A. (I then put the newly acquired sub, with my basic BX63, on another system). Needless to say, the newly acquired sub sounds terrific.

To the point: As soon as I powered up my main system, with the BX63A, it seemed there was (is) a notable improvement in sonics. (this is all other settings being equal-gain, and keeping the network set at 63Hz, same as a stock BX63). It could be my imagination, but I don't think so. I noticed better space, soundstage, and what seems a more relaxed and open presentation.

I'm pretty sure this has been covered here before, but I'm hoping those in the know will chime in with their thoughts on what would account for this apparent improvement. The technical sheet states that aside from the variable crossover frequency, the specs between the two networks are identical. Did the BX63A use better quality components? (esp. caps?) It seems to me it's been said on here in years past (giskard?) that the BX63 is actually a superior unit. I'm hoping gisk/4313B and others will share their thoughts on this...

Thanks

Peter

[Robh3606]

I believe the difference is added DC blocking caps and the Frequency Adjust

Schematics are here:

http://manuals.harman.com/JBL/HOM/Technical%20Sheet/BX63%20ts.pdf

Rob:)

[Doc Mark]

Greetings, Peter,

Oh, Man, you got my juices bubbling, now!! I thinking that your "new" 2241-based sub is not too different from the 2242 that I've been giving thought to making into a sub! I'll have to check the TS and see how close they are. I was thinking that the 2245 sub would smoke the 2242, or at least some folks do believe that this is the case, and from looking at the performance graphs, I would am inclined to believe them. Now, here you go and tell me that your 2241 sub sounds "nearly identical to my B460", and you definitely have my full attention!! Could you please take some measurements of your new enclosure, and send them to me? Also, I'd appreciate learning your porting information on that new cabinet, too.

It's really funny, but just today, I ran graphs on the 2235H vs the 2242H, and it appears that the 2235H has far better bass performance than the 2242H! :blink: However, after reading of your own thoughts on how good your 2242 sub sounds when compared to your B460, I'm eager to learn more about it. Thanks, very much, for any information you can share with me! Congrats on adding what looks to be another wonderful sub to your systems!! :applaud::D:applaud: Take care, and God Bless!

Every Good Wish,
Doc

[pmakres1]

Greetings, Peter,

Oh, Man, you got my juices bubbling, now!! I thinking that your "new" 2241-based sub is not too different from the 2242 that I've been giving thought to making into a sub! I'll have to check the TS and see how close they are. I was thinking that the 2245 sub would smoke the 2242, or at least some folks do believe that this is the case, and from looking at the performance graphs, I would am inclined to believe them. Now, here you go and tell me that your 2241 sub sounds "nearly identical to my B460", and you definitely have my full attention!! Could you please take some measurements of your new enclosure, and send them to me? Also, I'd appreciate learning your porting information on that new cabinet, too.

It's really funny, but just today, I ran graphs on the 2235H vs the 2242H, and it appears that the 2235H has far better bass performance than the 2242H! :blink: However, after reading of your own thoughts on how good your 2242 sub sounds when compared to your B460, I'm eager to learn more about it. Thanks, very much, for any information you can share with me! Congrats on adding what looks to be another wonderful sub to your systems!! :applaud::D:applaud: Take care, and God Bless!

Every Good Wish,
Doc

Hi Doc,

I'm not sure where to start...okay, like you I couldn't imagine a better driver than the 2245H. I don't know if I'm prepared to say that the 2241G/H is a better driver, but I will go so far as to say that I can't decide which sub I like better...my B460 or my newly acquired 2241 based sub. It has the same clean, deep, powerful and yet very musical qualities as the 2245H. It's teamed up with my 4313B's in my Florida Room system, which doubles as my art studio of sorts. (See pics). The electronics are based on Vintage McIntosh, a C32 preamp. an Mr77 Tuner and an MC2205 amp. The new sub is powered by a bridged Hafler DH500 amp. The new sub replaced a JBL PB12 that resided in the system. (no comparison at all). The sound is, in two words, simply beautiful. In studying the differences between the 2241/2242/2245 I find that the 2241 is 3db more sensitive than the 2245, (98db vs. 95) with the same power handling capacity (600W). I find that the 2242 is even more sensitive (99db) with EVEN HIGHER power capacity (800W). Of the three drivers, it appears the 2245 has the deepest, most extended response (20Hz), followed by the 2242 (25Hz), then the 2241 (30Hz).

In case you don't have all the data on the drivers:

2241G/H: http://www.jblpro.com/pub/components/2241.pdf

2242H: http://www.jblpro.com/pages/pub/components/2242.pdf

2245H: http://www.jblpro.com/pages/components/2245h.htm
also http://www.jblpro.com/pages/components/2245H.pdf

To be honest, Doc, I can't imagine you going wrong with any of these superb drivers. It may just depend on your priorities, or availability.

(I'm not sure how the 2235H could be a better performer than the 2242...though I do know the 2235H is a superb performer in its own right).

The 4313B's, with this new sub, sound simply beautiful. Not just with earthquakes and cannon shots-even at very low volume levels with delicate passages, the sound is simply beautiful. The 4313B is a smooth and nicely balanced system, but of course you can only expect so much from its 10" (LE10H, I believe) low frequency driver. You remove this limitation, and...wow!

Add to this mix the fact that the system is in a very small room, and when I'm painting, I'm sitting practically on top of the sub...and add to that the the increased efficiency of the 2241 over the 2245...and you have a very, very enjoyable setup that has lots, and I mean LOTS of headroom!

I don't think there are many subs, even today, that can compete with these 18" JBL professonal series sub drivers. They are simply superb.

The cabinet dimensions of my newly acquired sub are:

33-1/2" Wide
26" High
21-3/4" Deep, not including Grille frame
23-1/8" Deep including Grille frame

The square port measures 5.25" x 5.25" and extends 12" deep from the front baffle surface.

The enclosure has been very rigidly constructed with, I believe, 1" thick plywood (type unsure), is braced internally and is very amply insulated.
Like the B460, when the system is playing, cabinet vibration is virtually non existent.

I hope this helps...I know you'll be working on your project day and ight now!!:D

Best regards,

Pete

[Doc Mark]

Howdy, Pete!

WOW, what a fantastic response to my questions, and photos, to boot!! Thank you, very much!! :applaud::applaud: I think you answered all of my questions, and then some! :D

Your studio looks wonderful, Pete! I am hoping that, one day, I can get Sweet Bride's work studio into such nice shape, and can upgrade the music system we use in there to something better. I have most of the stuff, just need the time...

Your new sub looks very nice, and quite well done. Do you actually know the person who built it, or did it come from another person? Your systems always look so very well thought-out, and this new sub fits in perfectly, as far as I'm concerned! Much food for thought, Pete, and I do very much appreciate your efforts in this. I'm ready to get started RIGHT NOW, except that my efforts have to be channeled into other things, like work, home repair, plumbing, painting, felling trees in the forest behind our home, moving lots of dirt and some rocks, etc., etc.. So, as much as I'm chomping at the bit (and HAVE been for a very long time!), the rest of this stuff needs to be done first, and with Winter on it's way, time is in very short supply.

But, at least I have options, and when it comes to things JBL, that's always a huge blessing!! Thanks, again, Pete, and God Bless!

Every Good Wish,
Doc