SPL Stereo Vitalizer Mk2-T (tube) a beast of a loudness control at $1295

I like to mess about with the sound of my system and have found this unit. It is, in my estimation, a very sophisticated loudness control.

• 2-channel harmonic exciter
• Can enhance clarity, detail, loudness, and overall musicality
• Innovative filter network "de-masks" transient details
• Bass-focused compressor gives you impressive control over low-frequency dynamics
• Intuitive controls make it easy to shape sounds fast
• Equally effective on individual tracks and full mixes

I love this thing. It takes the flat poorly recorded techno music from the seventies(New Order...) and expands the depth and width of the sound stage as well as the dynamic range.

I imagine feeding this a Dolby B or C output from an old cassette player and being able to expand its dynamics. The same for analog I would imagine.