CJ...I'd also like to get a copy of the 610 schematic. I have a 6176 on the bench and the mic preamp is acting up. Thanks!
Quote from: "Brian Roth"CJ...I'd also like to get a copy of the 610 schematic. I have a 6176 on the bench and the mic preamp is acting up. Thanks!Brian, sorry to say but the schematic that CJ has might not help you that much with a 6176. He has a schematic I redrew from an original '60's era 610 and the 6176 isn't exactly a clone of that.
Well, *anything* is better than nothing, since Universal Audio has a "no schematics" policy!i
Ah, but that was 1999; we don't party like that any more.
The detail around the LF switch looks wrong; No difference between '+6' and '0' as drawn...Keef
any idead if this is the identical circuit as in the mono 610 or the 610 solo tabletop units?thanks
is there enough info on this to be buildable as is. Obviously for personal/educational use only.
Looks fine to me:...The other pole (top one as drawn) ... opens up C9 and R21 in the feedback loop and causes less L.F. feedback. You then gets mo' bass mo' fo'. :wink:
Not as drawn... you'd have to lose the connection to the common middle terminal to do what you describe... unless I'm reading the actuation of the switch wrongly...Keith
Phew! -I thought I was mad for a minute. :twisted: Keef
output section kind of looks a little like...
...also, is the 8mA in an A25 enough headroom for this output?
Yes a little. I seem to remember Paul Stamler saying the input stage is very similar to a Dynaco pre amp as well.A lot of these older circuits seem to have elements that look to have been lifted straight from valve data manuals. I have a UK Mullard one from 1959 (same year as the REDD47 was designed) and it contains pretty much the exact EF86 input stage for the REDD. Maybe this and the Dynaco and the BA-2A is just an RCA tube manual circuit? Then there's the 'White' output stage for the LA-2A which is in Howard Tremaine's book...