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New Project - Direct coupled 845 SE amp.
Posted: July 12th, 2020, 4:33 pm
by Roscoe Primrose
Haven't built his yet, but it's next up in the queue...
Roscoe
Re: New Project - Direct coupled 845 SE amp.
Posted: July 13th, 2020, 12:44 am
by FerdinandII
Haven't I seen this at your house before.......minus a few tricks?
Do you still have enough quiet 5842 tubes to do this?
Where are you getting your grid chokes from?
This one's going to be mono-blocks, right?
Re: New Project - Direct coupled 845 SE amp.
Posted: July 13th, 2020, 7:57 am
by tomp
Never saw a 100H choke.
Re: New Project - Direct coupled 845 SE amp.
Posted: July 13th, 2020, 8:09 am
by David McGown
Magnequest has a 100H/20mA choke, which I bet is what Roscoe is using.
David
Re: New Project - Direct coupled 845 SE amp.
Posted: July 13th, 2020, 8:14 am
by ratbagp
A proper boat anchor builder would line up 10 Hammond 193M inductors. 10H 300 mh 63 ohms and a respectable 10.5 lb each.
ray
Re: New Project - Direct coupled 845 SE amp.
Posted: July 13th, 2020, 9:57 am
by SoundMods
Roscoe Primrose wrote:Haven't built his yet, but it's next up in the queue...
Roscoe
Speaking of projects in the que -- did you ever build the tape-drive pre-amp you talked about? If you did -- how did it work out as compared to the stock electronics?
Re: New Project - Direct coupled 845 SE amp.
Posted: July 13th, 2020, 11:04 am
by Roscoe Primrose
FerdinandII wrote:Haven't I seen this at your house before.......minus a few tricks?
Pretty much. The regulated driver supply is a new twist...
Do you still have enough quiet 5842 tubes to do this?
Yes. I also have >150 8532s, which could also work great with a bit more inductance in the plate choke. Might need to get Dave Slagle to wind me a pair if I go that route.
Where are you getting your grid chokes from?
They're plate chokes, Magenequest. Been in and out of the stereo 845 amp for quite some time...
This one's going to be mono-blocks, right?
Absolutely. I'm getting too old to schlep around a stereo 845 amp any more
Roscoe
Re: New Project - Direct coupled 845 SE amp.
Posted: July 13th, 2020, 11:04 am
by Roscoe Primrose
tomp wrote:Never saw a 100H choke.
But you've heard them
Re: New Project - Direct coupled 845 SE amp.
Posted: July 13th, 2020, 11:05 am
by Roscoe Primrose
ratbagp wrote:A proper boat anchor builder would line up 10 Hammond 193M inductors. 10H 300 mh 63 ohms and a respectable 10.5 lb each.
ray
Nobody's ever accused me of being proper
Re: New Project - Direct coupled 845 SE amp.
Posted: July 13th, 2020, 11:06 am
by Roscoe Primrose
SoundMods wrote:Roscoe Primrose wrote:Haven't built his yet, but it's next up in the queue...
Roscoe
Speaking of projects in the que -- did you ever build the tape-drive pre-amp you talked about? If you did -- how did it work out as compared to the stock electronics?
Not yet. I did pick up a pair of late 60s Ampex solid state electronics, but haven't done anything with those yet either...
Roscoe