Funny you should ask, as I've been fighting with it lately. It did work out, for the most part. It has some noise, which a local tech diagnosed as improper power supply wiring. I always work for super short wires, but sometimes that leads to troubles.
Aside from those issues, it has worked and sounded great! There are so many ways you can go with and SE EL84 amp.
Paul
Aside from those issues, it has worked and sounded great! There are so many ways you can go with and SE EL84 amp.
Paul
I should add that to get the 12B4 stable I ended up using a stacked mosfet CCS and LED bias. I originally tried it with resistors at both ends, but it was motor boating. That may be somewhere in another thread. The CCS and the LEDs are both cheaper than decent resistors, too!
But, it probably isn't what most folks would want to do with this amp. Unless you need a preamp stage with serious drive, there is no good reason to cram one in to this chassis.
Paul
But, it probably isn't what most folks would want to do with this amp. Unless you need a preamp stage with serious drive, there is no good reason to cram one in to this chassis.
Paul
you wouldn't happen to know the specs of the output transformers? I have an el84 amp that I built based off of a motorola design and I was thinking that I could use the transformers from the M8 to make mono blocks based off that but keep the meters, and I was thinking about using 6SJ7's as the preamp stage, since I have two NOS pairs laying around.
You wouldn't happen to know the value of the resistor R25, the one that comes after the meter?
Thanks,
You wouldn't happen to know the value of the resistor R25, the one that comes after the meter?
Thanks,
Recently purchased an M8 and am using it as an amp-preamp combo using line ins for CD and speaker outs to my 90dB Peerless nomex/BG Neo3 desktop speakers. Plenty of level for listening within one meter, and it sounds great (using 7 1/2 Tone setting for a touch of roll-off). Apparently the Tone circuit is pre-shaping for the tape deck and can be bypassed. My right channel has issues so looking into it...
Using the M-8 with line ins/speaker outs with a stock unit:
-Set the Tape Speed control to OFF
-Press the Start button
-With the Play/Rec control set to Play, press the red button and while holding it, shift the control to Rec. The Record lamp will glow amber.
-Make sure the Monitor button is out to defeat the internal speakers.
Vintage Coltrane and modern Bonamassa sound wonderful. I've read that the amps may not be flat while the recording emphasis circuit is in place, so that merits investigation. Best luck with your rebuild(s).
Using the M-8 with line ins/speaker outs with a stock unit:
-Set the Tape Speed control to OFF
-Press the Start button
-With the Play/Rec control set to Play, press the red button and while holding it, shift the control to Rec. The Record lamp will glow amber.
-Make sure the Monitor button is out to defeat the internal speakers.
Vintage Coltrane and modern Bonamassa sound wonderful. I've read that the amps may not be flat while the recording emphasis circuit is in place, so that merits investigation. Best luck with your rebuild(s).
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