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midlife
05-17-2009, 01:29 PM
What larger than 15" bass driver could I use in a custom cabinet that will be using L65 xovers, mid, and tweets?

BMWCCA
05-17-2009, 01:59 PM
What larger than 15" bass driver could I use in a custom cabinet that will be using L65 xovers, mid, and tweets?I don't know much but I can tell you any JBL driver larger than 15" (which pretty much means 18") would be wasted with an L65 crossover which is crossed at 1,000Hz. The 18" I'm familiar with, the 2245, I use crossed at around 300Hz. The specs in this site's library say the highest recommended crossover point for that woofer is 800Hz. Same for the 2240 18". If you want to use an 18" woofer, be prepared to use the proper crossover to complement it. You may find it's actually better and not that much more expensive to go with a bi-amp setup using an active crossover like the Ashly XR-1001 and dumping the N65. I'm sure others with more knowledge will tell you what you can actually do with the N65 but it seems to me there's not a great reason to build a system around one. And I doubt you're going to achieve the sound of your never-to-be-forgotten L300s with that L65 mid-range.

If you're going to cobble up a DIY project, get ready for an onslaught of conflicting advice and opinions, but all will suggest crossovers other than the N65 or building your own.

ratitifb
05-17-2009, 02:58 PM
my god :baby:

why choosing a woofer for a specific X-over :blink:
instead of designing an adapted X-over for a specific woofer plus mid:dont-know

midlife
05-17-2009, 03:41 PM
my god :baby:

why choosing a woofer for a specific X-over :blink:
instead of designing an adapted X-over for a specific woofer plus mid:dont-know
Honestly, don't know alot about putting a speaker together, but if I see it as a viable project I'm going to give it a try. And yes, selecting the speaker components and cabinet first and then tailoring a crossover to complement the components does sound like a better way. ;)

BMWCCA
05-17-2009, 04:02 PM
And yes, selecting the speaker components and cabinet first and then tailoring a crossover to complement the components does sound like a better way. ;)You might even end up with something like my 4345s once you get carried away by the whole project. Or procrastinate and buy them from my wife at her yard-sale some day. ;)

Loren42
05-17-2009, 04:34 PM
What larger than 15" bass driver could I use in a custom cabinet that will be using L65 xovers, mid, and tweets?

The answer is you can't without modifying the crossover.

First, the selected crossover point will most likely be wrong for the intended purpose.

Second, the crossover should contain impedance compensation for the woofer it was designed for and will not match whatever you decide to put in there. The result will be impedance mismatches that will impact the crossover performance and phase coherence.

Additionally, you will need to select a driver with the same SPL level as what the crossover was designed for. This is not so much a crossover requirement as correct matching for the midrange and tweeter.

If it were me I would throw out the crossovers or sell them and tri-amp the system. Then you can use pretty much whatever you want as a woofer.

If I am right, the L-65 was used with a 12" woofer. Why would you want to go to a larger woofer?

Perhaps this is the real question we should be asking and then talk about how to resolve the issue.

hjames
05-17-2009, 05:06 PM
Honestly, don't know a lot about putting a speaker together, but if I see it as a viable project I'm going to give it a try. And yes, selecting the speaker components and cabinet first and then tailoring a crossover to complement the components does sound like a better way. ;)

Honestly - first you need to decide what it is that you want to do.
For a lot of folks, a good audio system is fine, and if you need more bottom for Pipe Organ music or watching TV or something, you can power up a subwoofer to fill in the bottom.

The folks here can share schematics for existing systems or thing that aren't too far off existing systems, but if you are doing a one of a kind system, design will mostly fall on you - and if thats not your normal skill set - stick to things you do well.

Its not MY skill set, frankly, and neither is building cabinets ...

If you want to hack up an L300 kind of system, it will cost money even scrounging around a lot of the pieces ... that was a REALLY well designed system and you won't just fall into that kind of sound by adding a 15 inch woofer to something else ...

I sort of hacked up a kind of L300/4333 type system in an L200 cabinet I got pretty cheap ... the parts were more expensive and I'm still not quite done - and I did wire up my own crossover based on a design 4313B had posted here ... crossover was about $300 in parts alone!

Not trying to be mean, just trying to help you find focus perhaps ...

spkrman57
05-17-2009, 05:41 PM
Sounds like what you might be looking for. ;)

Unless you have L65 minus woofers and thinking of modifiying them.:blink:

I would not unless you have to.:)

Just my 2 cents worth of course.:D

Regards, Ron

midlife
05-17-2009, 06:53 PM
spkrman57, I think your avatar is the direction I'll be going, probably will tune it with room location. ;):blink::D

BMWCCA
05-17-2009, 08:00 PM
I'd be the last to talk you out of using an 18" JBL. As I write this I'm listening to my 4345s for the first time in over a month—too much travel and too much going on in the living room when I'm not traveling. I've got to tell you, even at tiny volume levels the presence in the room of a big system is impressive (slight 0-5dB smiley Fletcher-Munson boost from the Soundcraftsmen Pro-EQ 44). Perfect soundstage, crossovers set at a tad over 300Hz, and Lyle Lovett doing his harmony with Ricky Lee Jones on Joshua Judges Ruth (thanks Fred!). Leland Sklar's bass lines are easy to follow—and feel—and yet my wife isn't telling me to turn it down!

Great recording, even with a crappy DVD player; fine electronics, and killer speakers. Nothing anyone can say to me can take away this experience. Go for it!

spkrman57
05-18-2009, 06:54 AM
spkrman57, I think your avatar is the direction I'll be going, probably will tune it with room location. ;):blink::D

I'm using a JBL 2225H in 3 cu ft cab tuned to 41hz, the 350hz tractix wooden Edgarhorn has a EV DH1-A 2" compression driver. Crossover is currently 800hz, but will be changed to 1.6khz since I'm seated only 7 ft from the speakers in my small room. Amplification is 300B triode amp!

Regards, Ron