Lately, I've been experimenting with using channel strips as a live bass rig preamp and have been VERY pleased with the results. After getting great bass tone from my Amek M3000 board running it thru a Urei 1176LN compressor in the studio, I figured it logical to try some of the channel strips that are currently available. I use Crown xti2000 poweramps bridged mono at 4 ohms which yield 2000 watts RMS, so that I never enter into the amp running out of power and introducing clipping or 'coloring' the sound.
MSRP $2500.00/ $2250-street.This is not really a bass preamp per se, but rather a stand alone, 2U “channel strip” that can also be used as a direct interface for a microphone, line level signal or any electric instrument. It does make an incredible bass preamp however, and features an all tube path using no less than four 6922 tubes. Although it is somewhat expensive, I love the sound of it. The parametric eq is fabulously smooth and warm and the optical compressor tube compressor very is useful. In other words, everything that you’d ever want in a high quality bass preamplifier. It is extremely well made and it weighs approx 22lbs. I updated/modified mine to have the ‘babyface mod’ which doubles the attack speed of the compressor. Although it's 100% tube, this preamp is for clean bass sounds only, but If you’re looking for one of the better preamps for bass, in my opinion, this is definitely one of them.
Here's a pic of the inside of my VT737SP:
Universal Audio 6176:
MSRP $2899 /$2399-street. This is my favorite bass preamp of all time. The LA 610's tube preamp section is fast, smooth and punchy. It's attack isn't as hard as the Avalon's, but rounder and has a much more transparent midrange. You can get very clean or very distorted/overdriven sounds from the preamp section, or anything in between, and although the equalization appears to be limited due to it being only two shelving controls, they are selectable and have found it to be plenty for any gig that I've encountered thus far. The FET based 1176LN compressor has always been my favorite compressor for bass, and the one in the 6176 is no exception. You can dial in the classic compressed tone, drive the heck out of it with the ALL setting, or run it a 1:1 just to get some of the 1176LN's color, which to me, is absolutely incredible. To me, every bass that I own sounds exactly as it should when I plug into this one.
Here's a pic of the inside of my 6176:
Universal Audio LA 610 MKII:
MSRP $1899 / $1599 Street. Another extremely nice preamp/DI for bass. It features the same LA 610 tube preamp as the 6176, but this time it's coupled with a tube LA-2 type opto compressor. The compressor is very simple to operate and sounds really good on bass, but I prefer the 1176LN in the 6176 quite a bit more. Still, its a great alternative if your budget doesn't quite allow the expense of a 6176. The original LA-610 was silver and black and weighed about 5 lbs more since it had a conventional power supply. The Mark II has a bit more gain, a larger VU, true bypass on the compressor, and a switching power supply, allowing use with USA an International voltages without having to reconfigure the unit.
Here's a pic of the inside of my LA 610 MKII
Focusrite ISA 430 MKII:
MSRP: $3499 /$2499 street. Here's another great preamp that sounds great for anything that you run thru it. Its versatility is almost endless with the ability to place any of the built-in processing in any order. The preamp section is big and almost completely transparent, with just a bit of that 'British' vibe. It tracks any bass really fast, without being stiff or 'hard' sounding. It has variable hi-pass filter so you can cut out the lowest frequencies to protect you speakers, as well as a variable low pass filter, which can be placed in the audio path, trigger the compressor, or the gate. The EQ in this unit is simply amazing. There is no interaction between the frequencies so you can slice and dice your frequency response very accurately. The compressor section is extremely versatile too, with your choice of three different types- VCA, Vintage optical, or Vintage limiting. With the VCA comp, you get fast and accurate clean compression that is completley adjustable for attack, threshold, release (or auto-release), and make up gain. With the "vintage' settings, you can run it clean, or dial in some distortion. And all of the comps feature a "blend" control that allows you to mix in the uncompressed signal with the compressed one. The gate is another nice feature, that eliminates any noise/hum coming from you bass when not playing. It gates/tracks beautifully. And if all that isn't enough,there's an additional soft limiter available on the final output so that you won't overdrive your power amp or speakers with too much gain. I've also recorded bass, vocals and drums with it using a Neumann 87ai, a vintage AKG c414 (C12K diaphragm) and even Shure SM57's and it has wowed me every time.
Focusrite Tone Factory:
MSRP $799 -NLA / $200-$250 used. I bought this one used on a whim for a very good price, and I'm glad that I did. Although I don't consider it a 'high end' unit that lives up to the Focusrite name, it does have some really nice features for an 'all-in'one' channel strip that is actually more suited as a bass preamp. The opto compression is unique, yet big and fat sounding, the EQ is very good as well as the gate easy to operate and very effective. There is a middle section of controls with EQ normally found on guitar amps that also can add even more 'color'. The only section that I found to be lacking is the distortion section, which sounds too artificial to me. I've used it as a bass preamp on quite a few gigs and it performed beautifully, with ALOT of punch and articulation. In my opinion, these are great units if you can't afford or justify the price of higher priced channel strips.