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Hoffman Amps Forum image Author Topic: yet another not a guitar amp.  (Read 2390 times)

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Offline DummyLoad

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yet another not a guitar amp.
« on: January 09, 2019, 11:30:33 am »
finished this one last night. KT88/6550 with edcor iron. 400V B+ to plates running in UL mode. ownder had a new pair of 1960's USA tung-sol 6550 and sylvania 6SN7. we ran it up with load resistors and tested with a signal gen and o-scope.


pics: https://www.dropbox.com/sh/uwlfhkx95nveylm/AADQ_oOvLqw7gyNFgEPYJEaXa?dl=0


--pete

Offline shooter

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Re: yet another not a guitar amp.
« Reply #1 on: January 09, 2019, 11:49:25 am »
NICE!  I like how there's more iron than tube  :icon_biggrin:

did you run siggen across the spectrum or just check clean/amplitude?
Went Class C for efficiency

Offline DummyLoad

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Re: yet another not a guitar amp.
« Reply #2 on: January 09, 2019, 01:35:09 pm »
thanks!


just basic. 60hz & 1khz tests. tomorrow night we use dist. analyzer and sweep freq.


--pete

Offline jjasilli

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Re: yet another not a guitar amp.
« Reply #3 on: January 09, 2019, 05:35:04 pm »
Nice & clean, straightforward build!  Hope all checks out as expected.

Offline p2pAmps

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Re: yet another not a guitar amp.
« Reply #4 on: January 10, 2019, 08:52:42 am »
finished this one last night. KT88/6550 with edcor iron. 400V B+ to plates running in UL mode. ownder had a new pair of 1960's USA tung-sol 6550 and sylvania 6SN7. we ran it up with load resistors and tested with a signal gen and o-scope.


pics: https://www.dropbox.com/sh/uwlfhkx95nveylm/AADQ_oOvLqw7gyNFgEPYJEaXa?dl=0


--pete

A man after my own heart Pete!  Nice work
Everything Affects Everything

Offline DummyLoad

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Re: yet another not a guitar amp.
« Reply #5 on: January 10, 2019, 10:53:10 am »
thanks for the kind words guys!


--pete

 


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