The headphone amplifier with VU-meters almost finished:
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https://www.banggood.com/NE5532-OP-AMP-HIFI-Amplifier-Preamplifier-Volume-Tone-Control-Board-p-1098533.html?rmmds=search&cur_warehouse=CN
The pre-amp uses two NE5532 low-noise integrated circuits
https://www.banggood.com/NE5532-OP-AMP-HIFI-Amplifier-Preamplifier-Volume-Tone-Control-Board-p-1098533.html?rmmds=search&cur_warehouse=CN