Hartke VX215 cab with Kappalite 3015's ?

timber22 · #1 07-02-2010, 02:00 PM

One of my rigs is a Hartke VX215. It's not the one I usually use to gig, but I'd like to use it more. I like the size and weight of it for a 2x15. It actually sounds pretty good but not "great". I'm thinking of replacing the 15's with Kappalite 3015's and disconnecting the horn. I'm not a big fan of horns in general.

Has anyone out there tried this, and can give me some feedback on the results? Did it make a noticable improvement? Or any other feedback on putting 3015's with no horn or mid-driver in a similar box?

JimmyM · #2 07-02-2010, 10:30 PM

not getting much activity on this thread, so in lieu of an actual hands on result, i'll bump it and say that i've seen where a few people have used them in similar sized boxes and had good results. whether or not you'll like the tone is another story. there isn't much of a consensus on it. some really like it, some don't.

will33 · #3 07-02-2010, 10:44 PM

I'll bump it as well. I don't know the size of a hartke 215 but the 3015 is fairly forgiving of cab size, within reasonable limits and has loud, high SPL response up to 3k more so plus good lows and a good xmax. It'll play loud and be able to take a good deal of power. If you don't want such prominent mid/treble response, maybe consider a Legend CB15. Little darker, not as uppermid/trebly.

timber22 · #4 07-03-2010, 06:06 AM

Thanks for the replies, Jimmy and Will.

The exterior dimensions are 40 x 27.5 x 16.5, so I guess that makes the interior volume in the 9.5 cu ft range. It has two round ports.

I don't "need" the 900 watts of power handling of the 3015, but I do prefer neo drivers for the weight savings. I believe the Legends are considerably heavier.

lbwdog · #5 07-03-2010, 06:30 AM

By most accounts here on TB, the 3015 seems to be the "go to" speaker for most replacements. Works well in a variety of cab sizes and tunings, handles as much or more power than most others, and is readily available.

I've heard some say that it's expensive, but at $140-$150, it's not much more than we paid for new JBL or EV drivers twenty years + ago. IIRC, K & E 140s cost around $120 in the eighties & nineties.

lbwdog · #6 07-03-2010, 06:48 AM

Quote:

Originally Posted by timber22

The exterior dimensions are 40 x 27.5 x 16.5, so I guess that makes the interior volume in the 9.5 cu ft range.

Probably less than that. If you take the exterior dimensions and subtract 3/4" for each wall, plus an additional 1/2" for the front baffle recess, then divide by 1728", you'll get around 8.4 cu. ft. That's the gross volume. Net volume would be figured subtracting for the displacement of two drivers, crossover (if applicable) and bracing.

Still within recommended range (1.8 - 5.1cu. ft.) for each 3015 though.

NoGraveConcern · #7 07-03-2010, 08:44 AM

Give us port diameter and depth.

That vol is a little larger then optimal (IMO), but will work fine. Past about 6.5 cu ft you get into the diminishing returns realm where going larger makes lf sensitivity higher but max spl doesn't improve and the response curve is no longer the nice, flat one that makes the 3015 so good.

8.4 cu ft will extend the f3 below 50 hz, but the drop off beyond f3 is steeper.

timber22 · #8 07-03-2010, 09:50 AM

Thanks. I have band rehearsal today and this cab in is the band room. I'll try to get the port dimensions.

timber22 · #9 07-03-2010, 05:08 PM

Two ports. Each is about 4 inches diameter x 4 inches deep.

lbwdog · #10 07-03-2010, 05:16 PM

Quote:

Originally Posted by timber22

Two ports. Each is about 4 inches diameter x 4 inches deep.

Sounds like a pretty conventional 2x15 cab with ports so I'd bet a pair of 3015s would sound great.
There are several guys on here that will model this for you, and I'd figure 8.4 cu ft for this purpose.

Johnny Mack · #11 07-03-2010, 06:28 PM

4.2 cu.ft. net interior volume is a big box for a 3015. optimal is about 2.75 give or take 0.25. tuning can be modified later, so no worries there. for $300 bucks, i wouldnt even risk it as long as the current hartkes are still kicking.

fwiw, i play 2 3015s in diy boxes with 2.86 cu.ft. tuned around 46hz. they were replacements for an old peavey 215 that barely functioned. they then moved to 2 diy boxes NOT made for them. they were over 3.5 cu.ft. tuned around 40hz. after owning them for a couple years i finally built cabs for them specifically to get the optimum performance out of them. this may or may not foreshadow your possible future.

timber22 · #12 07-03-2010, 07:28 PM

Thanks for the info. I appreciate it. Gives me something to consider.

NoGraveConcern · #13 07-06-2010, 04:52 AM

If that 8.4 cu ft is correct (I didn't double check) then that box is tuned to 34 Hz. Two things, one is that 34 Hz is too low--45 Hz would be about right for 3015's. Second is that 2 x 4" dia ports are not enough port area for 2 3015's. If you replace the 4" ports with two 6" tubes 4.5" deep you will have acceptable port area and a 45 Hz tuning.