Been away on holidays for a month so just saw this for the first time.
The second one is the "final" after tweaking circuit I used.
The first one has a missing resistor in the diff amp current source circuit.
The Baby Huey shunt feedback scheme relies on the diff amp swinging extra voltage to overcome the "local" feedback bein applied. There is accordingly a practical limit to how much feedback you can apply which usually will be around 6 to 9 dB (X2 to X3). Without Ultralinear taps some global feedback WILL be required to get output impedance down to a suitable level.
Use SY's LED bias scheme on the outputs, as he says above, this will give much better overload recovery.
Cheers,
Ian
The second one is the "final" after tweaking circuit I used.
The first one has a missing resistor in the diff amp current source circuit.
The Baby Huey shunt feedback scheme relies on the diff amp swinging extra voltage to overcome the "local" feedback bein applied. There is accordingly a practical limit to how much feedback you can apply which usually will be around 6 to 9 dB (X2 to X3). Without Ultralinear taps some global feedback WILL be required to get output impedance down to a suitable level.
Use SY's LED bias scheme on the outputs, as he says above, this will give much better overload recovery.
Cheers,
Ian
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