To Bi-amp or Not to Bi-amp, that is the question.

[edwin]

While the bass signal path is stereo, it's still mixed and panned mono at the FOH board. He just can get more deep into the tonal options of the DIs. Stereo doesn't have to mean panned left and right.

[sonicus]

Jazzy , in a BI -AMPed  signal , the signal is divided into highs and lows  that are separately amplified .
 
AN Alembic Series I/II in Stereo ; bridge & neck pickups separately processed and /or amplified.
 
 I think that what Edwin writes would be an excellent way to do it  ;
 
While the bass signal path is stereo, it's still mixed and panned mono at the FOH board. He just can get more deep into the tonal options of the DIs. Stereo doesn't have to mean panned left and right.
 
You are in luck that the engineer is granting you such a  large piece of sonic real-estate .

[fmm]

On a gig this important, I wouldn't want to test anything major in combat.

[bigredbass]

Random thoughts:
 
- I'd try plugging this all up somewhere else first, and see what you like and what you don't.  I've bi-amped before, and it can be confusing inasmuch as you may hear lots of the high pass, and not so much low pass, depending on the room.  Or vice-versa.
 
-Over the years, I've grown to think bi-amping with bass cabinets (ALL of which were designed as 'stand-alone' bins, not designed for two- or three-way operation as PA bins are) is maybe a crapshoot to begin with.  In the old days we did it, as there were so few good cabs and high-powered amps, no longer a consideration.  Having said that, I can think of no one that builds a 'system' of bass cabs designed for two or three-way operation.
 
-Then there's the consideration of that 'Gordian Knot' of all the control on a Series axe, plus the SuperFilter (and BTW, there's the F1X along the signal path, with crossover).  All of that Q and gain, I instantly understand why Jimmy plays direct and has his positions marked !  Amazingly, when I biamped, I'd set a neutral tone and jack the high pass for more treble, jack the low end for more bass, and never touched the tone controls.
 
-The 'classic' Alembic stereo idea was each pickup thru its own channel in the F2B, broken out to each side of a stereo power amp into separate cabs.  These days you could also go into a chorus or delay, to feed the two channels to get that swirl across the two, the same thing the Jazz Chorus does internally.  
 
-Then past all that, you're really only doing this for your stage sound:  After that, it's off into the house thru the Mains, where, hey, it's bi- or tri-amped depending on the setup, and any 'stereo' or 'chorus' effects would be applied.
 
I'm reaching for Tylenol just thinking this thru . . . Good Luck !
 
Joey

[keith_h]

Generally full range bass cabinets work best when run full range and you let the natural acoustical qualities work. When running different types of cabinets such as an 18 and 4X10 it is good to run them in dual mono so you can balance them but that is about it.
 
At one time Stanley Clarke's live rig consisted of two full range 18 running from the neck pickup and two full range 4X10 running from the bridge pickup. He also ran the bridge pickup through two 12 equipped guitar amps. In the early years the guitar amps were half Marshall stack but I have seen him use Fender Twins and these days some single 12 Fender. For the front end, other than the Carvin years, I have always seen him use one F1-X for the neck and another F1-X for the bridge pickups. To the best of my knowledge the basic building blocks haven't changed other than who makes the cabinets/guitar amps.  
 
Joey,  
Bag End builds bass cabinets intended for two-way use and the system controller supports 3-way although it isn't of much use for bass. This is what I use in my rig of 2, 18 subs and 2, 2X10 to handle everything above 98Hz.  
 
 
Keith

[bigredbass]

Keith, I knew about BagEnd, and have always wanted to hear an ELF (I don't care what they call it these days . . . ), but as is the case of most things Ron, it's hardly a conventional bi-amp set-up, as cool as it must be.
 
Interestingly, now BagEnd is offering self-powered cabinets, and yep, you can also get ELF built in.  Neat !
 
Joey

[dfung60]

Too late for advice on your gig, but I would keep life simple for the recording.  
 
Going DI is almost certainly going to give better fidelity sound in the recording than any mic setup on an amp, and certainly better than a multi-mic setup.  This will eliminate any shortcomings in the speakers and mic and guarantee that you're starting from a signal that has no phase issues.
 
If you go for a high-fi reproduction of the natural response of your bass, then you can DI from the output of your DS-5.  
 
If you like to EQ a lot, or use a compressor or other effects, then you want to DI from the point post your effects or right before the power amp.  By doing this, you won't be losing control of your compression or EQ to the soundman.  If you don't have a post-fx send on the amp, then you do create a problem where your changing the amp output level will change the recording level (that's why the soundman would rather take the DI directly from your instrument - only your instrument volume knob can screw the recording up then).
 
If you're Flea or Tim Commerford, and a highly distorted power amp is part of your signature sound, then you'll need a mic on the cabinet.  That's the only way authentically capture the sound of power amp distortion and speaker breakup.
 
For the recording, if they can capture a track with your cabinet mic'ed, they can get an idea of what you intended your sound to be and use it to sweeten the mix if necessary.
 
I've had bi-amp capability before, but never found it to sound great or be worth the trouble.  You need a crossover when the cabinet that you're using can't reproduce some of the spectrum you want.  If you like to use 18 speakers and you also want a bright slap sound, you can't reasonably expect the 18's to do it on their own, so you might add a cabinet with smaller speaker and crossover to split tasks. Now the 18's don't have to try to reproduce 4000Hz and the HF box doesn't need to be EQ'ed for 40Hz.  
 
If your HF speakers are 10, then if you had enough of them, you could reproduce the 40Hz (or at least 80Hz) cleanly, so why crossover?  It's hard to set up useful crossover frequencies that don't introduce phase shifts and notches and lead to you carrying around a lot of hardware.
 
Your mileage may vary!
 
David Fung

[jazzyvee]

Ok, we went neck pickup to 1x15 and bridge into 4x10. Tried do from bass then from the f1-x di and the engineer preferred the f1-x feeds. No sf-2 used at all. Both cabs were also close mic's. The rig we'd comfortable in volume and not loud on stage. I loved my onstage sound it was seriously incredible in clarity. I used my S1 for the first half and S2 for second and the difference there was clearly noticeable. The sound crew said they have never heard a bass that sounded this good clear and even toned. I will wait to hear the playback.  
I don't think bi smoking is something I will do that often as usually I only take one can to a gig and to be honest with two cabs on top of each other I couldn't hear a massive difference from mono. If I had an 18 inch or a 2x15 can on the neck pickup I expect it would be a different story. Anyway guys as usual you offer great insight for me and thanks for sharing your views and experience.

[lbpesq]

Jazzy:
 
Sounds like your gig was fun.  Post some audio if you can.
 
Bill, tgo

[jazzyvee]

Sorry my last post sounds odd the predictive text in my phone seems overzealous and changes words too drastically.

[elwoodblue]

entertaining though (Bi-smoking can get complicated )
 
I'd love to hear some of your gig too.

[keith_h]

I would really like to hear the difference an 18 inch or 2x15 can would make on the bridge pickup. To expand the idea would you use aluminum or tin, pop top or old fashioned lids? The possibilities are endless.  
 
Keith

[sonicus]

I have an old  Dual throat fold horn : loaded with a JBL K-151 that sounds awesome off a bridge pickup. It is an effective tool helping to obtain a JACO sound. Just a facsimile of that sound .

[sonicus]

Double post gremlin correction  
 
(Message edited by sonicus on December 14, 2014)

[terryc]

Low tech solution: Stick a mic in front of your amp..works for me everytime LOL