Need replacement for JBL 2225J

[Clammy]

So, I've come t the conclusion that the JBL 2225J speakers I have in my Marshall 1551 2x15 cab (dimensions: 29.75" x 29.3" x 17.5") are just not the right drivers for that cab, or the amp I'm using to drive them - an early 70s Marshall Super Bass. I've read a number of posts recommending Deltalite 2515 for similar lower-wattage rigs like mine (I run 2 Super Basses, each powering 1 cab), but I need either a pair of 16 ohm or 4 ohm speakers, as I need the total impedance to be 8 ohms, and it seems the Deltalite is only available in 8 ohms. Also, the speakers I have in the 4x12 cab have a sensitivity of around 100 dB, so I'm aiming for a similar number from the replacement 15s. Any suggestions?

Thanks.

Cheers!

[billfitzmaurice]

Originally Posted by Clammy

Any suggestions?

Get a larger amp. That's the only reason why a pair of 2225s would be insufficient.

[smoov]

Eminence Delta 15's come in 8-4-16 ohm. I have heard them and they sound pretty respectable..

[Clammy]

Originally Posted by billfitzmaurice

Get a larger amp. That's the only reason why a pair of 2225s would be insufficient.

Another amp is not an option.

Cheers!

[unclejane]

Originally Posted by Clammy

So, I've come t the conclusion that the JBL 2225J speakers I have in my Marshall 1551 2x15 cab (dimensions: 29.75" x 29.3" x 17.5") are just not the right drivers for that cab, or the amp I'm using to drive them - an early 70s Marshall Super Bass. I've read a number of posts recommending Deltalite 2515 for similar lower-wattage rigs like mine (I run 2 Super Basses, each powering 1 cab), but I need either a pair of 16 ohm or 4 ohm speakers, as I need the total impedance to be 8 ohms, and it seems the Deltalite is only available in 8 ohms. Also, the speakers I have in the 4x12 cab have a sensitivity of around 100 dB, so I'm aiming for a similar number from the replacement 15s. Any suggestions?

Thanks.

Cheers!

Holy smokes. It's hard for me to imagine how the 2225 (much less two of them) could be insufficient. That's one of the finest 15" drivers money can buy - what's the problem with them?

LS

[Clammy]

Originally Posted by unclejane

Holy smokes. It's hard for me to imagine how the 2225 (much less two of them) could be insufficient. That's one of the finest 15" drivers money can buy - what's the problem with them?

LS

They're just not a good match to the Super Bass head. The amp doesn't crank out super low frequencies, and these things seems to need to be pushed by a lot of watts. When I bought them, I knew nothing about 15" speakers (I only know a tiny bit more now! ). All I knew was that I needed a couple of 15s, and that JBL makes great drivers. I got a good deal on these, and put them in the cab. I also have a 4x12 cab I stack on top of the 2x15, and I never really noticed how much louder and fuller that cab sounds comapred to the 2x15 until I started running 2 heads, and I actually tried them individually. The 2x15 cab is quieter and has no balls at all. So, after reading a few threads here, and discovering that the 2225 is more of a PA subwoofer that needs a lot of power to drive, I've arrived here.

Cheers!

[billfitzmaurice]

If you'd rather have high midbass sensitivity than low frequency extension the Beta 15 will work well. But that makes the 2x15 response no lower than the 4x12, which begs the question: why bother? The only conceivable need for having more than four twelves is if they don't go low enough.

[Clammy]

Originally Posted by billfitzmaurice

If you'd rather have high midbass sensitivity than low frequency extension the Beta 15 will work well. But that makes the 2x15 response no lower than the 4x12, which begs the question: why bother? The only conceivable need for having more than four twelves is if they don't go low enough.

I would like some more low end, but it's clear that these particular speakers are not a good fit for the amp. Hence, the reason for this thread. And if, in the end, I wind up with a 2x15 cab that sounds the same as the 4x12, that would be fine too, as the 4x12 sounds great. I was just looking for a little more low-end "thud".

Thanks.

Cheers!

[unclejane]

Originally Posted by Clammy

I would like some more low end, but it's clear that these particular speakers are not a good fit for the amp. Hence, the reason for this thread. And if, in the end, I wind up with a 2x15 cab that sounds the same as the 4x12, that would be fine too, as the 4x12 sounds great. I was just looking for a little more low-end "thud".

Thanks.

Cheers!

It is true that the JBL 2225 is going to have a smoother freq. response in the mids, but for low frequency efficiency and low distortion, you've already got about the best drivers you can get. If you need more in the low mids, you'd probably do better to get a 4x10 or similar with a more pronounced freq. response in the low mids.

But for 50hz on down, you can't do much better than what you got driver-wise. Might just need to build a different cabinet for them (and hire a couple roadies to carry it around )..

LS

[BassmanPaul]

When you drop a driver, or two, into a cabinet that wasn't designed for that particular driver you get a crapshoot as to how it will sound. The 2225 is a great speaker but with a 400W power rating each you need much more that a 100W amp will provide.

As Bill opined, you need a bigger amp. Sorry but you can't change the laws of Physics.

[Clammy]

Originally Posted by BassmanPaul

When you drop a driver, or two, into a cabinet that wasn't designed for that particular driver you get a crapshoot as to how it will sound. The 2225 is a great speaker but with a 400W power rating each you need much more that a 100W amp will provide.

As Bill opined, you need a bigger amp. Sorry but you can't change the laws of Physics.

Yeah, I know it was a crapshoot. Like I said ealrier I knew NOTHING about bass speakers/cabs, only that JBL made great drivers.

As I said, a bigger/other amp is not an option. I'm not trying to change the laws of physics, but rather work with what I have, heheheh...

I know people run 2x15 cabs without having tons of power all the time, and that there are drivers more suited to that, so all I'm asking is what would be a suitable driver for a lower power application.

Thanks.

Cheers!

[BassmanPaul]

But again without doing the math you'll be dropping yet another pair of drivers into an arbitrary box and you'll be back to the crapshoot all over again! You would be better served by dumping the cabinet and getting one that WILL work for you. Driver exchange is an expensive way of cabinet design.

Edit: For the money you'll be putting out you could buy a bigger amp!

[Jeff Scott]

Originally Posted by BassmanPaul

But again without doing the math you'll be dropping yet another pair of drivers into an arbitrary box and you'll be back to the crapshoot all over again! You would be better served by dumping the cabinet and getting one that WILL work for you. Driver exchange is an expensive way of cabinet design.

Edit: For the money you'll be putting out you could buy a bigger amp!

+1

[Clammy]

Originally Posted by BassmanPaul

But again without doing the math you'll be dropping yet another pair of drivers into an arbitrary box and you'll be back to the crapshoot all over again! You would be better served by dumping the cabinet and getting one that WILL work for you. Driver exchange is an expensive way of cabinet design.

Edit: For the money you'll be putting out you could buy a bigger amp!

Well, I don't know of any decent amps that go for a couple hundred bucks, and I LIKE the tone and growl of my Super Bass heads, that's why I use them. No other amp sounds like they do.

As for the cab, it's outer dimensions are: 29.75" x 29.3" x 17.5". It's constructed of 5/8" ply, and the baffle tilts back about 1/2". Not sure what volume the speakers take up inside. It also has 1 6" round port cut into the baffle. So roughly, the internal volume would be (29.75 - 0.625)" x (29.3 - 0.625)" x (17.5 - 0.625 - 0.5)" = 7.91 cubic ft, or 3.955 cubic ft/driver.

Here's where I'm blocked, hehehe...

Cheers!

[Clammy]

Originally Posted by Clammy

Well, I don't know of any decent amps that go for a couple hundred bucks, and I LIKE the tone and growl of my Super Bass heads, that's why I use them. No other amp sounds like they do.

As for the cab, it's outer dimensions are: 29.75" x 29.3" x 17.5". It's constructed of 5/8" ply, and the baffle tilts back about 1/2". Not sure what volume the speakers take up inside. It also has 1 6" round port cut into the baffle. So roughly, the internal volume would be (29.75 - 0.625)" x (29.3 - 0.625)" x (17.5 - 0.625 - 0.5)" = 7.91 cubic ft, or 3.955 cubic ft/driver.

Here's where I'm blocked, hehehe...

Cheers!

I found the specs for the 2225 and the drivers themselves occupy 0.2 cu ft each, so the total internal volume of the cab (roughly) is 7.51 cu ft (3.755 cu ft/driver). I plugged the T/S numbers into the online version of ISD, and according to that, the volume is about double the "optimal" value. Now, the specs recommend 3 - 10 cu ft per driver, so from that point of view, they're ok... this is somewhat confusing. So, knowing the volume of the cab, and that I'm using a 100W amp to drive it (although old Super Bass amps are conservatively rated, and have been know to put out well over 130w, I don't run it wide open). Can anyone make a suggestion as to suitable drivers for this cab/head configuration? If more info is need, just ask, and I'll get it.

Thanks.

Cheers!