I am starting to build an all-tube microphone preamp. Planning to use two stages of 12AX7 and one 6922 SRPP output, now I am looking for the input and output transformers. Edcor looks to have what I need, but their web site does not a lot of information. Any suggestions on which Edcor transformer will work better?
Thx.
Thx.
I've never used Edcor transformers. I checked out their web page and looked at their mic input transformers, specifically their 1:8 ratio ones as that's the kind of ratio you need for a tube mic pre.
I note that:
1. Specs do not define the operating level at which measurements are made
2. There is no magnetic screening
3. They are quite inexpensive
I have no proof but I expect these are relatively poor mic transformers. You would probably be better looking at Jensen for example or Lunfdahl or Sowter.
Cheers
ian
I note that:
1. Specs do not define the operating level at which measurements are made
2. There is no magnetic screening
3. They are quite inexpensive
I have no proof but I expect these are relatively poor mic transformers. You would probably be better looking at Jensen for example or Lunfdahl or Sowter.
Cheers
ian
Originally posted by SY The Edcor plots I saw did specify the level. The left hand axis was marked "dBU." Distortion looked pretty good. [/B]
Yes, they did, but they fail to say whether it is input or output level; I suspect they are output levels. Also all the distortion characteristics look identical. I would very very surprised if a 23 dollar transformer can achieve better than 0.01% distortion at 10Hz at +18dBu output. If it can I'll take a truck load.
Cheers
Ian
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