Joule LA100 MKIII or Granite Audio 770FP or Modwrt

Thanks for the feedback. The amp is new to me, and I'm basing my preamp purchase on written info only. I sold my current preamp, and am starting form scratch with a tube pre. I'm sure I'll go through a few iterations before landing on great system synergy.

I've read that many Baron owner have found what they are looking for in a passive pre. I'm a bit afraid of losing dynamics. I've decided to start with an active preamp with relatively low gain (the ones I mentioned). A friend has a Promethius I can A/B with, once I get an active pre for comparison.

The 'tubey' sound I sited in the original question was just some thoughts, as many tube preamps reviews speak about the 'tubey' sound. Which I take as maybe a bit thick in the mids? I certainly don't want the highs to roll off early, if that is 'tubey' as well.

Lloydc,
Yes, my Baron has all the upgrades including the TriTube upgrade. You mention EL34. Do you mean the E34L that came stock with some of the TriTube amps, or an EL34? I've read the transformers couldn't keep up with the current draw from the E34L, and Mesa stopped recommending them. But I need to call them and verify. I have a set of 5881s with under 100 hours on them, and a set of E34L as well. I've got 3 bad E34L, so before I purchase more, I need to talk to Mesa and see what they say about running them vs. EL34 vs. other tubes.

The IRS Gammas do have an option to run full range. Even if the amp can keep up with the funky impedance drops (below 2 ohm for the lows), there are other reasons to biamp the IRS. They were specifically designed by Arnie Nudel to run through the factory stand-alone crossover/Servo. When running servo'd/biamp, the LF response drops considerably, and remains flat to around 15hz. Without the servo system, I believe they are good for around 30hz. I also like the idea of taking that work away from the main amplifier, as well as being able to tune the low freq response with the electronic xover in the servo.

I think I'm going to try the Modwright, as I've read elsewhere it is very nuetral sounding. Sounds like a great place to start, to learn the different voicing of the Baron. The Modwright is new enough that I don't have to worry about capacitor shift like some of the older preamps I'm looking at.

I've never heard a loss of dynamics running a passive preamp in my system. If your source has low output impedance, at least 2V output, and you're running short interconnects you should be fine since your amp is passive friendly. Furthermore, you can avoid most impedance matching issues that cause loss of dynamics by using a transformer/autoformer based passive (like the Promitheus) versus one that uses resistors. However, I own one of each type and again have had no issues with loss of dynamics.

I had the Modwright and the Joule. Two different sounds. The Joule was more tubey and the Modwright was neutral. The Modwright was more refined and faster though. I ended up keeping the Modwright at the time. The Joule is much more plump in the midbass (too much for my liking). The Modwright has more gain than the Joule also. I now own a Supratek, which is comparable quality wise to the Modwright, bigger sound (6SN7s) not as dynamic as the Modwright just as detailed and warmer. The Modwright did soundstage better. I'd go with the Modwright given the rest of your equipment. Get one with a tubed rectifier, suppose to make it warmer, and possibly the new caps, more refined.

Re the Baron, a few observations I have from operating my earlier model which used 5881's exclusively. It benefitted from a cap mod done by Mesa, using Wima Caps, but that is as far as I went.

The gain issue, and the sound as well, seems infinitly variable, with selection of the 'imaging mode' and feedback. The all pentode mode is very high gain and will create some loss of flexibility using a volume control, unless you have very low efficiency speakers, with out regard to whether or not you are using a passive or active pre-amp.

FWIW, in my experience anyway, the using a passive pre-amp has more to do with reducing the 'dynamics' often introduced by an active pre-amp, not necessarily to help match gain. I have the same gain issues with a line stage with a 12db gain as I do with a pre-amp with a 26db line stage gain (An ARC SP10, a Primaluna 3, and an EAR).

Re tubes....I've only used 5881's in mine. I tried some 6l6GC's but it wouldn't bias properly and I didn't want to have Mesa reset the biasing parameters. But, I have used, in other amps, the Tesla (Gold Aero badged) E34L's, NOS Tesla EL34's, and found them both on the bright side of neutral. Great clarity however, a nice crystal clear sound. IME (as well as that of others I think) the Baron doesn't need any help in the high frequencies. To the contrary, a little damping might be advantageous.

Based on my experience using these tubes in other amps, and my experience using the Baron, if I had the multiple type selection that you have I'd be very interested in trying out SED EL34's my favorite new production EL34, both because of its neutral sonics and its ruggedness as well.

yeah, the tube rectifier in the Modwright is worthwhile!