• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join free Log in
    Want zero display ads or expanded classifieds tools? Compare plans.

diy Kappalite3015+midrange

Q

qts

May 15, 2006
324
1
64
Ijmuiden-holland
#1
I'm thinking to build a basscab with the KL3015, and did some search on the forum if there are anny who uses a middriver, but i couldn't find anny.
most of the people claimed, this driver has a lot of mids by it self compare to the LF versoin
I also noticed BillFM metioned several times that all 12s and 15s need a middriver if you want these freqs reach the audience.

I want to go for a small cab 2.5cft ~50HZ (4string bass)
I saw this driver has enough low end, but i like also some mid punch, so it can cut trough the mix.

If so; Do i need a mid range driver for my needs?
Can i use the La6-CBMR for this configuration? so i can avoid a separate chamber.

thx in advance
 
#4
Not a lot of 6" midranges can hang with the sensitivity of the 3015. 2.5cf is a bit on the shy side, I would aim closer to 3, which makes getting the requisite baffle space for a midrange easier (since @ 2.5cf with a mid you're going to have an extraordinarily shallow or narrow cabinet, probably both).

Your choices are pretty much:
Beyma 605nd
18 sound 6nd410

The Faital 6Pr150 and B&C 6md38/6PEV13 all will do OK jobs, but not be quite as loud or take as much juice (and cost almost as much).

If you want a sealed back the only choice I see for keeping up with a 3015 is an Alpha 8MRA (which does not sound great IMHO, but is better than nothing).
 
#7
It'd take two alpha 6a's to even come close.

You might be better off going with an 8" driver if you want to cheap out. It won't disperse as well but it'll be better than a normal cabinet.
 
#8
I'm using 1 B&C 6.5 (about $90 from Parts Express IIRC) and it will easily keep up with 2 3015's. it's a really nice sounding driver. there is an old adage in the bass world that goes something like 'your tone is all about your mids'... It is very true and so your mnid driver is not a place to cheap out IMO. Basically it costs another $40 to get close to the top shelf...

Sealed chamber is the way to go. Study the plan of the fEarful 12+6. Note the mid speaker baffle brace. That forms the bottom of the mid chamber. the top is formed by a tight fit against the top of the cab. Then you need the side and back. It's way easy. Just cut a strip 3" wide and as long as the baffle is wide + 7 & 7/8. Out of that, cut off a strip of 7.75. That is your side piece, the remainder is your mid brace/mid chamber bottom.

Now you need a piece 8 " square for the back. Drill as small a hole as will accomodate the speaker wire to the mid.

Dry fit the baffle against the top of the cab & the side you chose for the mid chamber. Sand until you've got a nice snug fit. glue it, clamp it and let it sit. You get your mid chamber and some extra stiffness on your baffle board.

Anyone DIY'ing a cab should really study the fEarful plans and build info. It's really fundamental stuff - it applies to all of the cab's I'm llikely to be building... there is some extra work in there, a little extra cost but I'm aiming at a cab that will perform like a Berg, cost less than an Avatar and be easy to move as well... pretty sure I'll get there to! thanks to the efforts of Passinwind, Greenboy, Davio & Duke Lejeune among others ...

BTW -I'm also doing a 12+6. If you have enough power, it's a tough cab to beat...
 
#11
rpsands said:
Are you using the 6pev13 or the 6md38? Both of them are available for ~80 from beach :)
Click to expand...



6md38

beach - good to know as I'll need another. I'll have to consult with my local mentor for should it be the 18Sound or the B&C. I know he's high on the 18Sound ... might be overkill for me tho...

Crossover... probably not GB's... but maybe... See this is the icky part. The crossover has a HUGE impact on the sound of the cab... There are some obvious wrongs and some not so obviuos rights. By far the bast way to do this is to snag an active crossover with a known method (lp and hp slope) and a 2 channel power amp - then test. That will tell you a lot about where you want to cross.

On top of 2 3015's the B&C sounds really good - but different anywhere between 400 and about 800 - what I dig - you might not so you need to suss that on your own...

This is one more reason to adore the venerable old WT800A ... dump the amp you have now and grab an old GK 800 - tht's plenty enough power to make a 3015 & mid range dance in a biamped kinda way. There is probably some Carvin that will do this too but ... unless it is a dcm series power amp I have little faith in those folks...
 
#13
How much midrange sensitivity you want compared to woofer sensitivity may vary, but I shoot for actual parity, and look at pattern/dispersion matching so that the enclosure represents well in the far field. I'd rather "voice" with EQ after the fact and don't trust variable L-pads for beans until you get to the tweeter range where for electric bass especially it doesn't matter much.

4Mal said:
By far the bast way to do this is to snag an active crossover with a known method (lp and hp slope) and a 2 channel power amp - then test. That will tell you a lot about where you want to cross.
Click to expand...

More often than not, the passive crossover is an entirely different world. Component (include the drivers in that) interaction/reactance, resonance transferal... entirely different than active crossover / power amp combination which doesn't care a whole lot about these factors. Anyway, because of the many interactions, and the need to keep impedance curves in the safe zone, what works for active cross points may not even be practical with a passive. Let alone the difference in having easy deep slopes with actives, usually at least BW18 or LR24.
 
#14
The crossover specific for this configuration is the issue now.
I know the crossover calculators on the internet, and most the simple one, who don't take these parameters in acount cause they see only the nominal impedace.
I have two options then, to jump in de more profesional simulators as you (GB) use to find the perfect mach.
Or go to a Hitech audio company, were i did buy the componets for my earlyer build crossover.
The whole day a guy is experimentating with caps and coils, but i will take in acount it will not be for free
 
#15
A great crossover design often takes months, even - using a combination of sophisticated modeling software, impedance and Thiele-Small verification measurements of drivers in free air and then within enclosure, and component swapping after each round of on- and off-axis FR, etc.

All that is another reason I love bi-amping ; }
 
#17
If you're only going to take into account nominal impedance, wouldn't you do better just using something pre-built? Or even just using a horn and skipping the midrange?

The 3015 is pretty smooth up top and is pretty acceptable sounding without an Xover IMHO. High passed straight to a horn with no low pass would be totally usable, up around 2.5khz or so (although not ideal). You'd lose some off-axis, but gain simplicity.
 
#18
rpsands said:
If you're only going to take into account nominal impedance, wouldn't you do better just using something pre-built?
Click to expand...

It's not that hard to beat most of the ready-builts - only the Peavey ECS-3X because of its adjustability really has an edge. It's easy to beat them in component quality, and by using approximated impedance values at the chosen crossover point instead of just typing in "8 ohms". Even using the free air impedance at the point can beat the nominal value usually.

Or even just using a horn and skipping the midrange?
Click to expand...

Doing a lower-crossed horn takes a lot more crossover work to sound great than designing around a cone midrange.

The 3015 is pretty smooth up top and is pretty acceptable sounding without an Xover IMHO.
Click to expand...

Sound better yet with a small-format dedicated mid - especially when you consider further out from the enclosure.


High passed straight to a horn with no low pass would be totally usable, up around 2.5khz or so (although not ideal). You'd lose some off-axis, but gain simplicity.
Click to expand...

If you want not to stretch yourself at all, and call that simplicity, don't do anything at all ; } ...Don't bother building because there are a gazillion cabs that already do "simplicity". Improvement is beyond the next ridgeline, but you have to climb a little to get it.
 
#19
Honestly, I've tried a lot of cabinets and not a lot out there can compare to a 3015 and a horn in a well built box :) Nothing under a grand.

If you're using a horn too, the ECS-3X would probably be a good choice, but isn't it kind of a bad choice for a 2-way design?
 

Latest posts

Top Bottom
Back