LJ Line amp 2019

With my 2019 line amp, I wanted to create a simple but extremely refined line amp. With remarkable IC:s like LM 4562, it is not difficult, and it is not expensive.
The layout is simple, two IC's, non inverting configuration, and a volume control in between. About 10 times gain on the first IC, and the second works as a output buffer with unity gain, no problem, since 4562 is unity gain stable. I could have used a dedicated buffer IC, but since I know what loads the line amp will be exposed to, I stayed with 4562 due to it's low distortion.
Volume control is a true attenuator, only 2 resistors in the signal path. They are SMD, and 0.1 % tolerance, there are 24 steps. See picture with open amp. XLR in and out connectors, only one stereo pair in and out, no switches. Input impedance is 33 K ohms. Volume attenuator is 10 K ohms.
Power supply is +/- 15 Volts, and it is housed in a separate box. The supply electronics are all transistors, no IC's, and was originally made for me by a friend as power supply for a Hiraga moving coil preamplifier. Very stable, and very low noise due to carefully selected components – I will try to find a diagram and add it to this section. PSU connector is a 3-pole bayonet connector, rear, right on the amp.
Why LM 4562? First of all, the extremely low distortion. I also use my LJLineAmp2019 for my music making activities, and today's standards are high. I use 96 K Hz sampling frequency, 24 bit resolution, (32 bit float internally), soundcards with signal-to-noise ratios better than -120 dB, and very low distortion. I don't want to use line amplification that degrades the sound. (But yes, sometimes I do want coloration of the sound, and in that case I use other relevant electronics to do this type of job). Slew rate is 20 V per microsecond, and that figure is fine with me, I don't need a faster amplifier. IC's are socket mounted, not soldered, makes it easy to change if a new and even more fantastic IC appears on the market.

Front view of LJ 2019 line amplifier
LJ 2019 Line amp, front view.
Rear view of LJ 2019 line amplifier
Stereo XLR in and out, three-pole bayonet mount PSU connector to the right
Top view of open LJ 2019 line amplifier.
LJ 2019 line amp. SOTA volume attenuator, no switches, XLR in and out, power supply connector rear right.
Feature data sheet for LM4562.
LM4562 Features.