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Howdy Chaps, For starters it's been a very long time since I've been near forums like this. I think it was maybe 2006, so twelve years ago, I kinda gave up and moved onto other things.
Umm, Ampage... That was where it started for me, 2000 it would have been, a 166MHz 'puter and a dial up...
Anyway, here I am again and I've a ac10 schematic in front of me... I like it, reasonably simple (I was looking at the ac15 with tremolo too but, my God, I'd need to take out a mortage to get all those caps at higher voltages, then (it'd started with the ac30) maybe theres something even smaller and sure enough... the ac10.
This radio I have, though the tubes might be shot, it's basically got the power and output transformers, two 12ax7's, two el84's in push/pull, and three radio tubes so I should be covered.
Also I bought a box of about 8 x ef86's a while back at one of my favourite second hand dealers and before I gave up had a penchant for ecl82's (6bm8) as they were quite in abundance as single ended radio output tubes.
Okay... questions.
1. I don't want all the inputs (4) so was thinking of paralleling up the ef86 and the triode of the 6bm8 at the inputs just through mixing 68k's to each grid from a single input. Simple enough?
Then I'd, I suppose have the two 500k volume pots into say 100k resistors then together into the phase inverter just on the top leg. Another option possibly is each channel with 100k on the ends and across opposite ends of a single 1M pot with the wiper going to the phase inverter.
Also I have a few old reverb tanks from organs (I think thats where they were from) and I think I'd quite like reverb too! Referring then to this deluxe reverb schematic, I quite like the switch to bypass the tank and use it as a boost, and given one of my tanks has an 8 ohm input then is it likely, given small radio output trannies stuck on speakers usually 6", that that size of trannie would suit the paralleled up 12at7 shown on this schematic? (I know, I know, do the calcs... but I'm lazy and it's just at the beginning stages.)
Gosh, It's getting complicated... but given I then need another full tube to recover from the reverb I may as well use an 12ax7 whereby the second triode could be a cathode follower and throw in a set of tone controls as with all this going on I may need them!
Typical of me getting so complicated... gosh, no wonder at least half of the amps I'd built way back then didn't work! Well, more like a third... thing was I liked the construction of them, all the metal folding a cutting of holes, the wiring and the soldering, not to mention cabinet building... it was all so much fun that if it didn't work, I'd just start another one.
Hopefully this time around I'll be less inclined to go gung ho and spend a bit more time bread boarding stages... actual testing of circuits before committing to metal work and making special knobs on the lathe!
Thank you for taking the time to help me see right, Sean.
Umm, Ampage... That was where it started for me, 2000 it would have been, a 166MHz 'puter and a dial up...
Anyway, here I am again and I've a ac10 schematic in front of me... I like it, reasonably simple (I was looking at the ac15 with tremolo too but, my God, I'd need to take out a mortage to get all those caps at higher voltages, then (it'd started with the ac30) maybe theres something even smaller and sure enough... the ac10.
This radio I have, though the tubes might be shot, it's basically got the power and output transformers, two 12ax7's, two el84's in push/pull, and three radio tubes so I should be covered.
Also I bought a box of about 8 x ef86's a while back at one of my favourite second hand dealers and before I gave up had a penchant for ecl82's (6bm8) as they were quite in abundance as single ended radio output tubes.
Okay... questions.
1. I don't want all the inputs (4) so was thinking of paralleling up the ef86 and the triode of the 6bm8 at the inputs just through mixing 68k's to each grid from a single input. Simple enough?
Then I'd, I suppose have the two 500k volume pots into say 100k resistors then together into the phase inverter just on the top leg. Another option possibly is each channel with 100k on the ends and across opposite ends of a single 1M pot with the wiper going to the phase inverter.
Also I have a few old reverb tanks from organs (I think thats where they were from) and I think I'd quite like reverb too! Referring then to this deluxe reverb schematic, I quite like the switch to bypass the tank and use it as a boost, and given one of my tanks has an 8 ohm input then is it likely, given small radio output trannies stuck on speakers usually 6", that that size of trannie would suit the paralleled up 12at7 shown on this schematic? (I know, I know, do the calcs... but I'm lazy and it's just at the beginning stages.)
Gosh, It's getting complicated... but given I then need another full tube to recover from the reverb I may as well use an 12ax7 whereby the second triode could be a cathode follower and throw in a set of tone controls as with all this going on I may need them!
Typical of me getting so complicated... gosh, no wonder at least half of the amps I'd built way back then didn't work! Well, more like a third... thing was I liked the construction of them, all the metal folding a cutting of holes, the wiring and the soldering, not to mention cabinet building... it was all so much fun that if it didn't work, I'd just start another one.
Hopefully this time around I'll be less inclined to go gung ho and spend a bit more time bread boarding stages... actual testing of circuits before committing to metal work and making special knobs on the lathe!
Thank you for taking the time to help me see right, Sean.
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