http://www.thefret.net/showthread.php?t=13161
Doug White @ Jet City Amplification:
' Regarding the
JCA20H and comparisons to the SLO100 - I think there may be some misconceptions... Marnold has it right: there's no way a 20 watt amp is going to represent the tone of an SLO100. Of course there is A LOT more to it than I could write in one post, but let me just say, both our JCA20H and our JCA100H we personally designed by Mike Soldano, with his own hands and ears (various other body parts too). JCA20H sounds very "Soldano" and probably has more gain than most amps in it's class, but it isn't based on the SLO100 at all.
JCA100H has two channels, and the OVERDRIVE channel indeed has the now-famous-often-modelled-and-copied SOLDANO overdrive circuit which is also found in the SLO100. But! that doesn't make this amp an SLO100 either... there are many things which go into that amp which are beyond the scope of a single post.
But I can say with complete satisfaction that both amps (plus our combo and other stuff we are working on) sound VERY Soldano, because they ARE. And if you're looking for the signature SLO100 overdrive sound, the JCA100H delivers a pretty d@mn good version of it. '
' What makes us unique? There are a couple of tube heads for a bit less money than [the
JCA20H], but they're in the 5watt range and typically have only a single preamp tube and single power tube. There are several heads at 15watts or 20watts, which are at least $50 more than us, but typically $200 or more higher than us. So what out there offers 20 watts, 3 12ax7 and 2 EL 84 at only $299? As far as I know, no amp other than ours.
Transformers - VERY important! We started with a Soldano
Atomic 16 and the goal of making a highly similar transformer to the American-made trannys in the Atomic. I personally worked with the transformer maker and through both critical listening and Audio-Precision measurements, revised the design probably 4 or 5 times. THEN Soldano himself compared it to his original tranny and even though he was happy with what I had done, made a couple more improvements and then signed off on the final version. So we spent some important time on the trans and I'm very pleased with how it turned out. Hopefully, you will be too. '
'
20H and
2112 [combo] are both based upon the
Astroverb circuit but are slightly different. 20H has more gain cos he's just a head without verb, so we could crank him up. 2112 we slightly backed off the gain cos the higher gain with reverb just isn't as desireable. Plus, the 2 extra tubes in the circiut for the reverb itself do change the signal path a little bit. Not sure I can hear it, but it is on the scope. And of course he has an open back. '
' Andy Marshall (owner of THD) and I have been friends for several years now, and have been wanting to do a project together. So when I told him about Jet City, he had the idea to contribute the
PicoValve -- it's 5 watts, with a 1/2 power switch, and full EQ. It also features Andy's cool "swappable power tubes" topology, which allows the player to use almost any octal power tube without changing the bias or any other settings. It will be playable at NAMM, and available on the street probably March. '
'