Biamped rig for bass and more

[:bassist:]

First post here but I've been lurking for a while.

I decided to toss out some info and pictures of the bass guitar rig I built. Inspiration and plans for the LF section came from greenboy's fEarful project on talkbass.com.

The LF driver is an Eminence Kappalite 3015LF in a fEarful 15/6 cabinet. The 15/6 plans call for a small chamber for an 18Sound 6ND410 mid. I decided to build a separate mid-high cabinet using two Eminence Alpha 6A drivers so I left the mid chamber out of the 15/6 cabinet.

The highs are handled by an Eminence ASD1001 compression driver on a JBL PT-B99HF-1 90 x 90 waveguide. The mid-high cabinet uses the MTM format and is used in an upright position to maximize horizontal dispersion.

The HP filter for the 1001 is a Duke LeJeune/AudioKinesis design. Duke's comments explain why no LP filter is needed ahead of the 6" drivers.

I'm using an active crossover from Marchand Electronics and there is an honest 400 watts available to the mid-high cab and at least that much available to the bass cab. Power for the top end is supplied by a Yorkville XS400 head and the bass cab is powered by (please don't laugh) a Behringer PMP2000 in bridge mode. The Yorkville head also performs preamp duties. Crossover point is 900 Hz--chosen based on Eminence FR graphs for the 15" and 6" drivers.

One of these days I'll get around to putting some kind of finish on the bass cab. I'll probably get a Peavey IPR1600 soon to power the bottom end. The B* powered mixer's amp section works well but I'm not sure about its reliability. Dig that crazy project box that houses the crossover :D

Comments and such are welcomed. Thanks for this great site!

:bassist:

[jeff_free69]

Re: Biamped rig for bass and more

Nice - should sound awesome for bass!

I used same woof and mid components for a bass & keyboard rig.

How are those active crossovers? Can you change the frequency?

The alphas can also go way lower than 900. But that should based on a preference for how much body you want out of the bottom and how much articulation you need out of the top and vice-versa. Sometimes the hardest thing about setting up bass amps is that everybody seems to hear it except the guy with the guitar standing in front of it

BTW if you find it sounding a little "clangy" or forward especially on fullrange material, you may want to revisit the lack of a hi cutoff on the alpha6 . Its not as bad as most pro drivers in this range but there is a definite bit of breakup/peakiness in the 1 - 5 K range. but then again, it might just what the doctored ordered for your Rickenbacker (or whatever bass you play)!

http://www.eminence.com/pdf/alpha-6a.pdf

[:bassist:]

Re: Biamped rig for bass and more

I used same woof and mid components for a bass & keyboard rig.

I didn't mention the "and more" part before. The rig sounds very good for playback of recorded music at home and also does a good job on vocal reinforcement at rehearsals.

How are those active crossovers? Can you change the frequency?

From the Marchand website: The crossover frequency of the XM1 electronic crossover can easily be changed by changing the value of four resistors. These four resistors are mounted on an 8 pin DIP header plug for ease of change.

The alphas can also go way lower than 900. But that should based on a preference for how much body you want out of the bottom and how much articulation you need out of the top and vice-versa.

I was going for flattest possible FR. The 15 gets ratty above 900 and the 6s are less sensitive below 900--according to the Eminence graphs anyway.

Sometimes the hardest thing about setting up bass amps is that everybody seems to hear it except the guy with the guitar standing in front of it

BTW if you find it sounding a little "clangy" or forward especially on fullrange material, you may want to revisit the lack of a hi cutoff on the alpha6 . Its not as bad as most pro drivers in this range but there is a definite bit of breakup/peakiness in the 1 - 5 K range. but then again, it might just what the doctored ordered for your Rickenbacker (or whatever bass you play)!
http://www.eminence.com/pdf/alpha-6a.pdf

I bet a Ricky would growl real nice through this rig. I know my Fender Jazz does

Cheers and thanks for the reply,

:bassist: