Gyraf Audio Gyratec 23-S Preliminary User's Manual

Gyraf G23-S Tilting Equalizer
Gyraf Audio Gyratec 23-S "Ambler" Linear Tilting Equalizer.
Preliminary user manual, 17. May 2018. Edit May '20.
The Gyratec 23-S Tilting equalizer is a tone control based on a
somewhat different concept. Instead of going with standard 6dB/oct
"first order" filters with their inherent phase/group delay around
cutoff frequency, we approximate a 1dB/oct filter which
distributes the (necessary) phase clutter over eight octaves. This
results in a very unobtrusive response - even at extreme settings
the material will tend to stay in balance and subjectively sound
unprocessed.
On top of the tilting tone control, we have added a very-gentle
Baxandall tone control with shelving lows and highs and a bell
mid, each with three selectable corner frequencies.
Our interpretation of the the "Tilting" equalizer does not have
selectable corner or rotation frequencies, as the linear approach
makes this unnecessary.
The -S addition for the G23 designates an added solid-state
architecture – with the bypass switch in the "S" position, we
bypass the usual transformers and tubes, and wrap the tone control
circuits in servo-balanced active circuits instead. This for
situations where you need the enhanced cleanliness or huge drive
capabilities of solid-state.

In use:

First of all, when turning on the Eq, allow the unit to heat up
it's tube department for ten to fifteen minutes - to get the tubes
stabilised in their working temperature. The sound and operating
levels for the non-S setting will change slightly within this
period.
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