I have a Motorola HS-711B console (16w)(4-EL84's and 12AXTx2 with a 5U4G) I got with no output transformers? I'm going to re-cap and do a full resistor R&R and make it a stand alone. It has a huge PT. The orginal OT's were from the schematics 5500 Ohm input and 6-8 ohm out.
I thought I might get a better FQ responce and sound by taking the coulping caps up from .02MFD to say 1.5 or .22 and putting in a pair of new OT's-These are the two I am looking at-suggestions?
25w
input-7.6K ohm
Out-8-ohm
20-20K Hz responce
Screen/grid-40%
OR
60w
input 10K ohm -it would lower the gain by about 1dB
out-8 ohm
20-20K
S/G-40%
I also thought about doing a UL Mod by going to pin 6 on the EL84's with a in-line 100 Ohm 2w resistor from the OT's?
Your thought are appreciated and I would inc the schematics but I get a "File size to large".
I thought I might get a better FQ responce and sound by taking the coulping caps up from .02MFD to say 1.5 or .22 and putting in a pair of new OT's-These are the two I am looking at-suggestions?
25w
input-7.6K ohm
Out-8-ohm
20-20K Hz responce
Screen/grid-40%
OR
60w
input 10K ohm -it would lower the gain by about 1dB
out-8 ohm
20-20K
S/G-40%
I also thought about doing a UL Mod by going to pin 6 on the EL84's with a in-line 100 Ohm 2w resistor from the OT's?
Your thought are appreciated and I would inc the schematics but I get a "File size to large".
Also,I'd be careful about your proposed coupling cap values. I'd start with double the 'stock' value(0.047uf),and go from there. Beware that too large of a value may cause LF stability problems,.22 might be a bit on the large side. 1.5uf would be insanely huge,and is likely to cause problems,IMO.
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