Getting old 1960s microphone preamps to work in their sweet spot is a quite excessive progress. I took a new old stock aluminium frame, fitted one phantom power 48 Volt and one Tonader T-power 12 Volt power supply from Sennheiser in the center of the frame. The transformers have been custom mu metal shielded to achieve absolute quite amplification within this tight space. Four V376 on the left, four V276 on the right are set next to the power supplies. To get the cleanest and most reliable 24 Volts to the preamps I chose two FUNK Studiotechnik power supplies. One for each four preamp sets. It’s simply the cleanest audio power supply available for this application. Only high end cable materials were used inside the custom rack. After months of testing and finally building this setup, I assume this to be the most compact yet quiet and clean 8 channel Sitral rack. One DB 25 connector goes out of the rack to the attenuator and the Metric Halos.