Suggestions on driver stages for big tube MI amps.

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I was hoping to get design suggestions for driver stages for my pet project, a big 200W tube bass head. It's more a thought exercise at this point, as I'm sure the price of a 200W OPT with good bass response will shock me back into reality.

As to what's already out there with 200W driver stages, there's of course Dogzilla:
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with its DC coupled followers, which is basically what an Ampeg SVT uses:
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There's the Weber AB200:

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which uses an interstage transformer, which is a little unique for MI.

Thoughts? Of course using SS followers is always an option but I wonder if that might not be a goode solution for MI.
 
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Nobody cares? Just thought of another candidate, how about a DC coupled pentode LTP like in the Tim Mellow OTL? I don't think I've come across that yet topology in commercial MI amps, but I bet that is because using small tubes as drivers is much more cost effective.
 
I like ampeg and would start there. What's the deal with Weber going the mile with a transformer coupled EL34 as driver (which would be able to truely drive the output tube) but wasting the potential with series capacitors and 15kohm gridstoppers? Might as well use a wimpy 12ax7 then!
 
I like ampeg and would start there. What's the deal with Weber going the mile with a transformer coupled EL34 as driver (which would be able to truely drive the output tube) but wasting the potential with series capacitors and 15kohm gridstoppers? Might as well use a wimpy 12ax7 then!

The more I look at the Weber design the less I like it. I think you're right about the grid stoppers: they are that size to primarily limit grid current when overdriven and not just to prevent RF oscillation. I looked at pictures and the interstage transformer is just a wimpy little thing. I think it's probably a mediocre design wherein reusing as many existing catalog parts as possible was a primary design objective.
 
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