porous
Member
First post. I am no tech by any means but have successfully recapped a few of my tube devices and because I linger here have checked out all the info available for the Altec 438A.
Okay, I bought this on ebay about two years ago for $260, which was cheap but it looked like it had been sitting in a damp garage for about 20 years, literally. I spent about 12 hours just cleaning it, but all xformers and the meter worked. Then I replaced all the film and electrolytic caps and got her up and running. Its acutally pretty good. I will be building proper I/O pads, and have the so called EMI mods to install.
Heres my questions about the mic pre. Would there be any sonic advantage to 'upgrading' the mic pre circuit with fancy resistors like Caddock or Roederstein? (R1, R2, R3). C1 is a 50mf 3v electrolytic which I replaced with one of those 50 cent blue off the shelf things with the arrows on em, Nichicon or Panasonic, I think. (Aluminum?) Would it help to replace this with a Black Gate or some other fancy cap? How about the resistors in the power supply or changing the input pot to conductive plastic? Though the unit sounds good as is I'm basically trying to lower the noise, not that its really noisey, but is not as quiet as a Manley Varimu.
Thanks in advance. Mark.[/i]
Okay, I bought this on ebay about two years ago for $260, which was cheap but it looked like it had been sitting in a damp garage for about 20 years, literally. I spent about 12 hours just cleaning it, but all xformers and the meter worked. Then I replaced all the film and electrolytic caps and got her up and running. Its acutally pretty good. I will be building proper I/O pads, and have the so called EMI mods to install.
Heres my questions about the mic pre. Would there be any sonic advantage to 'upgrading' the mic pre circuit with fancy resistors like Caddock or Roederstein? (R1, R2, R3). C1 is a 50mf 3v electrolytic which I replaced with one of those 50 cent blue off the shelf things with the arrows on em, Nichicon or Panasonic, I think. (Aluminum?) Would it help to replace this with a Black Gate or some other fancy cap? How about the resistors in the power supply or changing the input pot to conductive plastic? Though the unit sounds good as is I'm basically trying to lower the noise, not that its really noisey, but is not as quiet as a Manley Varimu.
Thanks in advance. Mark.[/i]
