This page is about the IMPACT 1017 100W amplifier head.
The amp on the pictures is my own. I have got a couple of reports about others of these. Some in Sweden, some in the UK. I guess there wasn't many made.
One unusual thing about this one is, that it's cathode biased and have no global negative feedback. In reality it's more of a 70W than a 100W amp. It has four ECC83/12AX7 and four EL34/6CA7 tubes.
The power amp section is very similar to the Vox 80/100 amp, the forerunner for the AC-100. It seems as that amp is known for overheating and following failures, and it was certainly a problem with this one too, when I got it. It's really a bad design, as far as speaking about the biasing of the power tubes. They are running far above there maximum plate dissipation with the original values of the cathode resistors.
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