Diy "Hi-Fi" Bass Rig

[sumsound]

Hey All I've posted this project mostly on the talkbass forums but I figure I'll post it here.

I built this bass rig out of the desire to have something that was as close to as clean sounding as a studio monitor as possible but be fairly small, and loud enough to be useful live, with some serous Bottom extension. The bottoms needed to be no larger than a Marshall Half Stack.

Oh yah and I had some old JBL bullet Tweeters (Not Exactly Hi Fi) that I've had sitting around for 13 years or so, and figured I should do something with them.

What I built:

a Dual 8" top box that uses RCF L8S800, JBL Alnico Bullet.
12dB/24dB per octave LR

Should do from 100Hz-16kHz arround 122dB per box

I also built a Sub.

Its a sealed Linkwitz-Transform/ELF style sub
Its ~4Cu'

This think will do 20Hz at ~110dB full tilt

About 117dB @ 30Hz, and about 127dB above 50Hz.

Uses 4 Eminence Lab 12 drivers and is powered by 2 1kW ICE amps.

[Moondog55]

Nice paint job.
Is that a six string bass??
Do you play with them stacked like that or seperated??

[zoranaudio]

The paint is LAW 'N...sexy

[sumsound]

Originally posted by Moondog55
Nice paint job.
Is that a six string bass??
Do you play with them stacked like that or seperated??

I have been playing with them seperated or single.

But If I play with them stacked I would probably turn the Top one upside down to try and get some sort of a array like effect with the bullet tweeters.

I used Duratex (african Violet)

Yes it is a 6 string Ibanez BTB

Nice Active Bartolini.

[qguy]

NICE !!!

how low does a Bass guitar go ?

[TheSeekerr]

Low E is 41hz, no?

[sumsound]

Originally posted by qguy
NICE !!!

how low does a Bass guitar go ?

Depends

5 string is tuned to B0 normally which is ~30Hz fundamental
Drop tune the instrument a whole step. So the low string is A0 27.5Hz
The same as the Low a on an 88 key piano.

In actuality it takes a fairly special EQ slope to get the same amplitude response with relation to 2nd harmonic at those fundamental tones due to the pickup placement practicality.

Ideal position for a pickup to get maximum signal from open string fundamental is dead center between Nut and bridge. This places the pickup in the 2nd harmonic null.

Anyhow the sub is good enough to be used as a home theater sub, or the whole rig would make a great keyboard rig also.

All that said a typical commercial bass rig seldom has real performance down to 60Hz let alone 40Hz.

Clean bass in those low registers is pretty cool, but may not be what a lot of bass players are comfortable with, especially Jaquo wanna bes.

Its a fun rig, still tweaking the limiters and EQ on the subs.

Its nice to have a built in DSP engine.

Antone-

[Don Snyder]

Hi Antone ... you've done a great job.

Some time ago, we had some dialog on the Tapped Horn Collabrative about various
efforts to produce good sounds for techno. While most use synth, one guy built a
three string extended length bass with bridge mounted piezos. Of course, piezos
have their own problems, but the low end didn't roll off like the electro-magnetic
pick-ups.

Do the active Bartolini pick-ups get down to 27 Hz?

[nickmckinney]

Originally posted by sumsound
Clean bass in those low registers is pretty cool, but may not be what a lot of bass players are comfortable with, especially Jaquo wanna bes.

Looks good. Guy who used to assemble the Lambda drivers early part of 2001 actually played drums with Jaco a couple of times. We built some true low bass tuned cabinets but found room mode issues a problem at every place we tested them. 30Hz and below just doesn't cover the dance floor evenly like 40+HZ.

[sumsound]

Originally posted by Don Snyder
Hi Antone ... you've done a great job.

Some time ago, we had some dialog on the Tapped Horn Collabrative about various
efforts to produce good sounds for techno. While most use synth, one guy built a
three string extended length bass with bridge mounted piezos. Of course, piezos
have their own problems, but the low end didn't roll off like the electro-magnetic
pick-ups.

Do the active Bartolini pick-ups get down to 27 Hz?

From what I understand, the pickups are sensitive to string displacement and velocity, to a point i think they are fine for Sub bass tones, but the high frequency is determined by pickup RCL characteristics and pickup aperture.

If you play with this pick up applet, you can slide the pickup around up the fret board and you see what the relationship between string displacement, fundamental and pickup placement.

http://www.till.com/articles/PickupR...emo/index.html

Basically the string is a 1/2 wave radiator, the center of the string 1/4 wave where maximum displacement happens.

I'd like to know more about these Neck Piezos.
It doesn't sound like it should work for electric bass since the neck is supposed to be fairly inert, and it is coupling the mechanical vibration of the body of the instrument. I guess it would be cool to put a contact pickup on a bass and take an FFT of what is happening.

I've been thinking about clamping a pickup to the neck of an old bass that I have and seeing how it sounds having much more fundamental energy picked up.

Originally posted by nickmckinney




Looks good. Guy who used to assemble the Lambda drivers early part of 2001 actually played drums with Jaco a couple of times. We built some true low bass tuned cabinets but found room mode issues a problem at every place we tested them. 30Hz and below just doesn't cover the dance floor evenly like 40+HZ.

Yes thats always a problem.

The only thing that can improve problems like that is room placement to try and find the best compromise.

I've heard of using out of phase speakers in the room to help change the intensity of positional room modes, but don't know if that will help for room coverage in the sub registers.

Good fun

Antone-