Insides of Lazarus H-1A amp...

"I wonder if a good tech can take the H-1 to H-1A level? risky without schematics?"

Uuh...what would the tech DO? Without a H-1A schematic diagram and an H-1 amp, he/she wouldn't know what the differences (= upgrades) are.

Jsujo, yes.. risky to upgrade to the H-1A without schematics. But a good tech can always change the factory pc to something exotic and have the circuit board resoldered with lead-free, 4% silver solder. These tweaks will help. But if you're set on an H-1A, I have a lonely unit not in use.

I have two of the "Class A" models in mono right now, using the XLRs... sounds pretty darn good. :-)

If anyone is interested, I have lots of Lazarus literature & reviews. Jsujo, one review compares the H-1A stereo amp versus H-1A monoblocks. The monoblocks had more separation between instruments and better high frequency extension.

I have an H-1A and would be interested in any specifications (damping, slew rate, etc.) or literature available.

I am considering using it as the bass amp in my biamp system.

Jsujo, there are lots of improvements a knowledgeable technician can make to an H-1. It's full of capacitors and resistors, large and small, that can be upgraded. I've started upgrading caps on mine, replacing the lo-voltage PS bypasses on the bottom of the board. But I still want a schematic diagram of the circuitry before I do much more.