"My Overcomplicated Bi-amp Rig" or "How I Leaned to Love the Boom"

[FugaziBomb]

In my introduction thread, @rwillett encouraged me to expand on my Bi-amped bass rig.  Before I get into it, let me provide a little background:  I was playing in a reggae/hip hop band and my 8x10 set up wasn't hitting as hard on the low end as the DJs were between sets, so I decided to ditch a traditional bass amp in favor of some dedicated subs.  Eventually, this is what I put together:

 

 

This oversized monstrosity is my bi-amp rig.  It consists of two 18" Peavey subs each independently fed 500w from a Crown XLi2500 power amp to handle lows and an Eden 210XLT mated to a Mesa Stereo 2:Fifty tube power amp for another 50 watts of valve goodness to handle everything else (I'll get into a more detailed signal path later - it's really convoluted).  The idea was to have a lot of headroom for lows while the highs can benefit from that "edge of breakup" tube thing guitarists are nuts over (it turns out 50 watts is way too loud to push that hard, but I like the way out sounds in it's capacity, so I held onto it).  Another reason for it was that I didn't want to be limited to just using "bass" effects, so having a bass rig that was essentially a guitar amp sitting on top of a pair of subs meant I could use any pedal and still be fine.

 

So here's the rundown:

 

 

(This is a VERY dated picture of my board, but it's better than nothing.  Everything is pretty similar these days, but I've added a dedicated splitter instead of using the parallel outs from the wireless.  I also swap out my drive pedals a lot depending on my mood)

 

I house everything in two separate racks for weight dispersal.  One rack is signal processing, the other is power. My signal is split at the pedal board into two paths:

 

The clean signal - which will be for lows - bypasses all the effects and goes right into a Polytune.  The Polytune is nice because it acts as a mute, so I can kill the lows if I want to do some subtle work in an intro or breakdown passage of a song without all the bombast of big, round low end in the mix.  Anyway, this clean full range signal goes from the pedal board to a small crossover unit which can be seen just below the power conditioner.  I only use the low output of the crossover, so it's playing more of a low pass filter in this role.  I pass this at around 350 hz (one of two low pass operations it will go through) and send the signal to a sub harmonic synth (the Peavey Kosmos on the bottom of the processing rack).  The Peavey is a glorified octave pedal more-or-less.  I low pass my signal before it to remove a lot of the high-order harmonics that will make it sound like an octave pedal.  I only want it to "see" a certain frequency to taylor it's response.  In this role, the sub harmonic synth not only adds a lot of EDM style lows, but it keeps my lows very strong as I climb the fret board.  After the sub harmonic synth, the signal then goes to channel 1 of the EQ.  This is where I get rid of the rest of the mids and only leave up to 100hz (again removing any vestiges of the "octaver" sound) to be sent to channel one of the DBX 1066 compressor.  I set this to 4:1 with about 6-9db of gain reduction.  This really evens out the low end regardless of how soft or hard I attack the strings.  The DBX compressor has two outputs.  One goes right into a Radial ProDI for FOH (which has a ground lift I sometimes seem to need), the other goes into the Crown XLi2500 housed in the power rack.  From there, each side of the Crown feeds one dedicated subwoofer.  This thing hits HARD.  I can really make it uncomfortable in a room if I want to, but that's not what I'm after.  I'm after head room, and man do I have it.

 

The other signal routes through my pedal board in a very traditional manner, ending with a dedicate mute for the highs so I can have just lows to do that hip-hop/EDM thing when needed.  Also when I tune, I need to be able to mute both signals.  Anyway, from the board, it goes into the Demeter VSBP-201s tube preamp.  I run the input gain on this kinda hot so I get a little bit of break up as my baseline tone.  It's pretty subtle as the Demeter is a very clean tube preamp.  After that I use the XLR out with the Jensen transformer to send it to channel 2 of the EQ where I cut everything under 100hz and from there, into channel 2 of the compressor.  This side of the comp is set to 2:1 and barley nips the peaks of the waveform for pretty minimal gain reduction.  It's really nice for taking the peaks off the envelope filter I have on my board, which can get unruly, but it isn't very aggressive on my dynamics.  From there, the signal goes to the Mesa Stereo 2: Fifty tube power amp (loaded with 6L6s) housed in the power rack and then out to the 2x10 Eden cab.

 

The problem with all this signal pathing is that it's very cable intensive.  Because of this, I had to get a little OCD with cable management: 

 

 

 

I made all the power cables myself to specific sizes so that I could route them out of the way of my audio signal cables.  All the power is routed along the side of the rack case.  I used two heavy-duty power connectors to link the power amp case to the processing case which houses the power conditioner.  I also used two green LED indicator plugs for the power amps.  I did this so that I can tell if I have live power without looking at the front of the amp. 

 

The last step of the equation is how to send all of this to FOH.  I covered that with the lows - they get sent off though a DI right to the desk - but the only way to get the highs out front is to mic my 10s with an SM57 like a typical guitar amp.  I think that's the best way, though.  Otherwise without the high end filtering of the speaker cones, the drives and sawtooth synths would be pretty harsh.

 

And that's that - the world's most convoluted, over-the-top, back breaking amp.  I hope all of this made sense.  It's very complicated and it took a lot of trial-and-error to optimize it and bring it to it's current, final iteration.

 

It's worth noting that this is a throwback to my days of touring midsized to large venues.  It's wildly impractical for small clubs and I'm in the process of building a more compact version of it with a powered sub and a Trace Elliott 1x10 with a 20 watt lunchbox amp on top of it all.

 

[Lozz196]

I think trying to understand all of that would give me more of a headache than hearing it at full blast. Pretty much left me behind at the 810 rig. I’ll bet it sounds amazing though.

[Beedster]

I’m looking to bi-amp ahead of some gigs in June, there’s so much info there, I’m going to come back to it on a clear head tomorrow, but in the meantime many thanks for posting @FugaziBomb 👍

[FugaziBomb]

15 minutes ago, Beedster said:

I’m looking to bi-amp ahead of some gigs in June, there’s so much info there, I’m going to come back to it on a clear head tomorrow, but in the meantime many thanks for posting @FugaziBomb 👍

The biggest thing to takeaway is that sometimes it's more advantageous to overlap frequencies instead of using a traditional type of crossover.  When I used the crossover, I had a hard time sitting on a mix.  Either my lows were just rumble or my overall tone sounded thin, depending on how I balanced the crossover.  Now that I overlap 100hz, I don't have that problem at all.

[BassmanPaul]

You know if I had to carry all that stuff around from gig to gig I think I'd retire1! Best of luck.

 

[FugaziBomb]

1 hour ago, BassmanPaul said:

You know if I had to carry all that stuff around from gig to gig I think I'd retire1! Best of luck.

 

It used to be I had people to carry it for me.  It was a lot cooler back then.

[rwillett]

Simple, subtle, innocuous, subdued, understated....

 

Five words that have nothing to do with your setup.

 

I had imagined something slightly less than the control room of NASA 😊 it looks fantastic and I have no chance of replicating anything here apart from the tuner. 

 

However I am going to play with biamping just for the hell of it. 

 

Keep this thread going. It's great. 

[BigRedX]

I ran a bi-amp system in the 90s, but that was mostly so I could put certain effects on the HF side only. Also the way I had my rig set up allowed me to have the HF speakers at ear level which allow for better monitoring and lower backline levels on stage. The dual DIs for the PA feed did tend to confuse some in-house FoH engineers so we ended up with our own sound engineer. These days it can all be done within a decent must-effects pedal and the results summed at the output for direct feed to the PA.