Here’s a bit on the Lingo 1 which came out in 1990. Back in the day many LP12 owners used Naim amplifiers and the stock Lingo did not behave well with the grounding system of Naim. A special earthed Lingo lead CONN 401/E which applies to amplifiers with floating earth, which rely on the turntable to earth the system (not Linn amps).
I thought the move from Valhalla to Lingo was well worth it. At the time Linn dealers had a Valhalla in a box to make listening to the two options very easy to switch between using the same LP12. I was running a LP12/Ittok/Troika with a white lined pre-Cirkus bearing on a floor standing Audiotech table at the time with an Exposure 15 integrated amp through Quad ESL-57’s.
The Cirkus bearing came out three years later…
Lingo Power Supply
Date Introduced: 1990 The Linn Lingo is a high precision, direct coupled, power supply designed to sit alongside the LP12 turntable. The Lingo upgrade moves the LP12's performance into a new league, further distancing it from the competition.
At the heart of the Lingo are two very low noise crystal oscillators derived from the Linn Numerik digital studio recording system - one for 33.33 rpm and one for 45 rpm. The switch on the turntable selects the appropriate oscillator, the output of which is fed into a synchronous counter to produce a 50 Hz or 67.5 Hz square wave for 33 rpm and 45 rpm respectively.
As the LP12 motor runs at its quietest when driven with a clean sinusoidal waveform, a precision filter is employed in the Lingo to remove harmonics from the square wave leaving only a pure wave form.
The most uniform torque is delivered from the motor when both phases are driven at ninety degrees with respect to one another. This is achieved by a ninety degree phase-shift network after the filter. The two resulting sinusoids drive two high voltage class A amplifiers, the outputs of which drive the two motor windings.
The Lingo uses 'stall detection' circuitry to feed the motor with a higher voltage for increased start-up torque. When the platter reaches the selected speed, this load-sensing circuitry reduces the power output. From then on the motor just maintains the platter's own inertia to keep it going silently.
A toroidal transformer on the PCB, and a mains filter, give a very high degree of electrical isolation from the mains voltage supply.