Last time I looked it was stable to unity, so you can generally adjust it
without fear of instability.
Hm. Bi-amping with F4 and J2 unity gain? Oooh, la, la! And here I thought this was a family friendly forum
I will see what I can figure out.
Bi-amping with F4 and J2 unity gain? Oooh, la, la! And here I thought this was a family friendly forum
I don't actually recommend it - the front end can't see the full voltage output
swing as an input without issues.
Ok, with gain around 5.5 (90.9K + 20K), reduced CCS current on the front end (now 8mA) and a lower bias through the output stage (from 1A to 0.8A at 24V rails), I think it will all work just fine. Adjusting the diode current in the CNY didn’t do much to reduce the bias, so I added a resistor across the transistor side of the opto to adjust the voltage.
All this meddling allows me to not externally cut the gain at my active crossover, which was my goal.
So, still have some gain so hopefully back in “recommended” territory.
I suppose that raises the question of why not a F4J - despite the fact I don’t have enough devices...
All this meddling allows me to not externally cut the gain at my active crossover, which was my goal.
So, still have some gain so hopefully back in “recommended” territory.
I suppose that raises the question of why not a F4J - despite the fact I don’t have enough devices...
Ebay is listing a pair with an amp around them : First Watt J2 Stereo Power Amplifier - Nelson Pass - Audiophile - Made in USA | eBayI cant find at any price, or I might snap up another set as back up. The ones I have came from Semisouth...the member not the company,,,,well, both I guess.
Russellc
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