It does not matter lin or log because the range from 0 to 50k is the most audible. Further you can use any decent pot because you do not use it as often as the volume pot.
I use often the origenal chinese volume pot with i replaced for a Alps type.
Ronny
I use often the origenal chinese volume pot with i replaced for a Alps type.
Ronny
Well i have searched and searched but I cant find the 5.1k feedback resistor. Its supposed to be in series with the 8 ohm tap but i cant see anything there.
Edit: photo attached . My finger is on the wire leading to the 8 ohm tap
Edit: photo attached . My finger is on the wire leading to the 8 ohm tap
Attachments
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If that feedback resistor is "missing" then you do not appear to have the correct circuit diagram.
I would suggest drawing out exactly what you do have before trying to alter anything.
I would suggest drawing out exactly what you do have before trying to alter anything.
I will try once i get a replacement tube for the one i blew - along witb a cooked resistor
Fu50 kit
Wondering if anyone else has had a fru50 kit from "douk audio" in China?
I purchased one and not happy, parts missing and when completed did not work. No anode voltage to 6j8p and fu50. This kit has a printed circuit board.
Any help or info appreciated.
Wondering if anyone else has had a fru50 kit from "douk audio" in China?
I purchased one and not happy, parts missing and when completed did not work. No anode voltage to 6j8p and fu50. This kit has a printed circuit board.
Any help or info appreciated.
I got one a year ago. It was missing about four resistors and the caps were not real, they were fakes that popped after two days. I replaced them with proper caps and they were fine. I'm using SS rectification so I had to wire it differently that suggested. Oh yeh, no schematic was ever sent.
It sounds ok but I'm going to see if I can use the output tubes in another project.
Good luck!
It sounds ok but I'm going to see if I can use the output tubes in another project.
Good luck!
I got lazy and implanted some resistors in the wire rather than a pot (will insert the pot next week)
Anyway I am using 2 x 47K resistors in series on each side, so very little NFB now.
I actually prefer the sound this way. Noticable changes:
Smoother / softer presentation
Less soundstage width
More soundstage depth
More "analogue" sounding
Much less bass, and a bit less upper mid / treble emphasis - this works as I have woofers below that are SS powered
Fun experiment
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Douk audio are good with refunds in my experience. I would ask them for one.
I bought mine as a completed kit from seller "diytalent86"
Have had no problems so far and im very happy with the sound
That was so they could be pulled out hot and replaced on the fly! These tubes were used in mission critical devices so they needed a way to pull them out and pop in a new one. Cool, huh?
Still enjoying this amp. The GU50 is a very nice tube
Im planning to perform some more mods but will need some guidance
Could some please tell me the purpose of the 47uF and 330uF capacitors in the circuit? Should any of these be replaced (could be mismatched) or removed?
I remember that there is a trace that has to be cut to use a tube rectifier. Take a look at the traces around the react.