frequency response for a 2x15

I'm a newbie and I need a little help. I recently bought a vintage bass head and I want to build a cabinet for it. The original cab for this head was a 1x15, but this head certainly has the power to be played through a 2x15, which is what I want to design and build.

The original cab (from the early 70's) was a 1x15 ported cab with no tweeters or anything. I've seen plenty of vintage 1x15's and 2x15's that have nothing in the box other than the 15's.

My question is this: what sort of frequency response can you get out of a simple 2x15 cab? Can I get by on just a couple 15's? I play only four string basses, so I don't need to get down to 30Hz or anything, but I do get up on the D and G strings more often than your average bassist. I don't slap or pop that often, but I do occaisionally. So should I plan on adding a tweeter to my cabinet or a 8" or something? Any advice will be greatly appreciated.
 
You might be suprised to hear what comes out of those 15's. You could try it before building the cabinet to see if you like the upper end or not. Just hook up your speakers to the head and play, no need for a cabinet (you won't have any bass this way).

I would suggest a semi-full range speaker instead of a tweet of any kind. How many bass cabinets actually have the tweet turned on? They are always turned off by the player.....

Something like these speakers would be a good choice for a smoother top to your cab.

http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=290-015

http://www.partsexpress.com/pe/pshowdetl.cfm?&PartNumber=295-010&DID=7


http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=295-015

I would hook it up with an L-pad and tweak to suit.

Good Luck!
 

Brett

Member
2002-01-07 6:02 pm
Almost all single cone 15's will be rapidly fading not long after 1kHz. I don't like whizzers on bass drivers as with the long excursion required to get some decent SPL, they tend to go muddy.

It depends on lots of things, whether you'll like the top end on a 2x15, including what you play, style of music and where you want to sit in the mix. A lot of people like the 'old school' 2x15 sound, but I personally find it a bit limiting. My personal rig is a 1x15, 1x12 and 1" on a large flare. All the drivers are very high quality pro drivers, actively driven. If you just want the thud, it's easy to roll off the top end.
 

Brett

Member
2002-01-07 6:02 pm
Forgot to add, for the bottom end, Hoffman's Iron Law still rules. Most bass boxes are usually rapidly fading below 60-80Hz, even the 15's. Each octave lower you go, you need to move 4x the air.

You don't need 30Hz on stage, even with a low B, and even if you did, it'd likely cause problems. So long as the second harmonics are there and clean and strong, the brain will fill in the rest.