ca21

"I can't think of another line preamp under $8k that I'd rather live with - it's that good!" - Dick Olsher, The Absolute Sound.
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The ca21’s full-size chassis provides a much larger playground for Mystère’s European engineers. It gives them space, a tremendous advantage for less restrictive designs, for more and improved power supplies, and for the most advantageous wiring positions.
It takes a lot of trial and error to find the best route for wires; the more space, the more options—but ultimately, the better the result. With these separates, the results are phenomenal.
Like the ca11, the ca21 uses an SRPP (Series Regulated Push-Pull) circuit for high gain, low distortion and very low output impedance by using a variation of the White Cathode Follower. The circuit uses no negative feedback for more natural tonality.
It uses a single 5AR4 for rectification followed by a massive pi network consisting of a big inductor, separate left and right channel capacitors, regulator circuits and DC filament supplies.
Further improvements are realized by using a larger power transformer and increased power supply filtration. Add this together with high quality, heavy duty, 24-step volume attenuator and fast, wide-band polypropylene caps, point-to-point wiring with rigid copper wire, loosely insulated with silk tubing and you have a linestage preamp second to none.