Cliff Schecht wrote:I built a quad KT-120 bass amp recently and it was all the way loud. ~550V on the plates and each tube idled about ~75mA IIRC.. They get REALLY hot though, enough to where I'm installing fans in that amp once I get some time. Here's a gutshot before I put in the final e-caps.. I still owe you guys a proper build thread, maybe after the thesis is finished..
Oh Cliff, I know you're busy, but when you get a chance you've got to tell us more about this beast. I remember the original thread where you were debating various topologies. I've been waiting for a followup ever since that thread.
Yeah I plan on it, I have better pictures and a full schematic drawn up too. I have to finish my thesis and defend on the 18th, so after that I should have a lot more free time to post. Considering how complicated this thing is, it turned on and worked with relatively little hassle. I think it was more just myself being nervous about redplating such massive output toobs..
Mark: I think 550V was plenty of HV for these tubes. Remember that I went with an ultra-linear output transformer so I'm running the screens at pretty high as well. I surely could have gone higher voltage on the B+ but the PT I used had over 1A of current available on the HV tap (!!!). I figured that was beefy enough to make a lot of noise. I might get in there and figure out a way to increase the drive to the power tubes though, I feel like it *could* be louder before clipping .
Considering how cheap (including sockets), I'm tempted to build one into a display style head cab. That idea automatically gets derailed because I have no place where I can actually "turn it up." Even if I was home alone in my 33' x 16' living room, I don't think that would work. Then there is the matter of a cab to take that sort of power. Nope, won't be doing it.
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