QSXM2 Ultra Extreme RIAA amplifier
This is a masterpiece when it comes to vinyl listening experience, an ultra high performing RIAA amplifier which can handle MC and MM cartridges. I have put lot's of work into the design and every built amp have worked right away. All visible metal surfaces are covered with 24 carat of gold (ENIG). It's an unpopulated pcb.
In order to get an extremely linear and extremely low distortion design I have taken a couple of measures:
- Configurable for both MM and MC cartridges
- Symmetrical design
- No capacitors in the signal paths
- Cascodes in the input stage and in the high gain stage
- Buffered cascodes with emitter followers
- Possibility to use ultra low noise transistors
- High speed output stage
- Advanced input bias servo with chopper stabilized or conventional opamp
- Totally DC-coupled together with DC-servos and input bias current servo
- Many decoupling capacitors and EMI-filters
- Professional quality printed circuit board with groundplane
- The pcb has lot's of possibilities when it comes to tweaking. You could use JFET's as input transistors for instance.