500 Series Stereo Bus Tube Saturator RSE TS508

The 500 series device works in stereo mode. Each channel has its own input&output transformers and two tube stages - triode and pentode ones, so four tubes stages in total.
All tube stages are powered with a high-voltage built-in source.
Calibration screws for each channel on the faceplate, to ensure stereo balance is easily maintained.
Input gain, output trim, and a final dry/wet mix at the end of the circuit. Unity gain is when the input knob is fully counterclockwise and the output knob is fully clockwise.
Bias controls for both the triode and pentode stages, and a mix knob to blend the two tube stages, or remove one if the mix knob is fully clockwise or fully counterclockwise.
Emphasis EQ section inspired by the Goodhertz Tupe plugin. Consists of a low shelf, mid-bell, and high shelf before the tube stages, and an inverse low shelf, mid-bell, and high shelf after the tube stages.
12 o'clock is flat on all bands. Counterclockwise will cut the pre-tube band and simultaneously boost the post-tube band. This results in de-emphasizing the tube saturation on that band, without lowering the band's volume. Clockwise turns past 12 o'clock does the opposite.

https://on.soundcloud.com/kY4Ab7Rk82evWgzLA

Technical Specifications

• Input/Output signal level: +20dBu
  
• Frequency response :  20Hz-20kHz
• Size: 500series*2slot
• Number of channels: 2 (stereo operation)
• Plate voltage: 200VDC
• Transformers: RSE TL5.001 (amorphous core)
• Tubes: 6Ф1П (ECF80) - may be changed
• Indication: Analog VU in/out meter + Input clip indicator
• Controls - smooth potentiometers
• EQ: empasis (low shelf <200Hz, mid bell =1k, high shelf >2k)