dmp
Well-known member
Anybody have a schematic on the conversion to a mic pre? I have a converted one that I'm trying to figure out. There used to be a schematic floating around but I can't find it now.
Ampex 351 micpre conversion info needed
- Thread starter dmp
- Start date
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ethervalve
Well-known member
Check out this thread:
http://www.electricalaudio.com/phpBB3/viewtopic.php?f=5&t=498&hilit=ampex
http://www.electricalaudio.com/phpBB3/viewtopic.php?f=5&t=498&hilit=ampex
ethervalve
Well-known member
oh right you are...
searching for the file name yielded this though:
http://www.flickr.com/photos/elmiko/5072897541/sizes/l/in/photostream/
searching for the file name yielded this though:
http://www.flickr.com/photos/elmiko/5072897541/sizes/l/in/photostream/
dmp
Well-known member
Thanks! That is the schematic I was looking for.
nielsk
Well-known member
You don't have to do anything to convert it to a mic pre, it already is one. Just put the output switch in the Record position. The question is figuring out what was done to mod anything, it can help to have the original docs...
Everything is available here:http://recordist.com/ampex/apxschem.html
Everything is available here:http://recordist.com/ampex/apxschem.html
dmp
Well-known member
It looks like it has just had the unused tubes removed and then recapped.
I'm looking at making a 2 channel, 2U version for use as micpres. It seems like the input transformer is pretty interesting, but sowter makes a copy. I'll say I tried it out last night and it has a very different flavor from any of my other pres. We found it awesome on vocals.
I'm looking at making a 2 channel, 2U version for use as micpres. It seems like the input transformer is pretty interesting, but sowter makes a copy. I'll say I tried it out last night and it has a very different flavor from any of my other pres. We found it awesome on vocals.
nielsk
Well-known member
If you are looking for color, stay with the original, they do come up available... I think the sound of it has a good deal to do with the output, basically a power amp. Tons of drive :
vincentgallo
Member
- Joined
- Mar 24, 2016
- Messages
- 7
Anyone using an AMPEX 351 as a mic pre please consider selling me your bias coil which is no longer need in your circuit
[email protected]
[email protected]
vincentgallo said:
I think I will perform a mod to an Ampex 351 for a Mic pre soon, the owner might not want that part.
Do you have pictures of what it's the Bias Coil?
