LCR Transformers

Silk Supermalloy SQ annealed core, MU shielded, most accurate and consistent RIAA we’ve seen. These LCR RIAAs are built with the best Supermalloy core inductor to perform within +/- 0.5dB from RIAA standard (from 20Hz-20KHz) or in the average of less than +0.15dB from the standard.

Wiring diagram:

The color-coding of the wiring instruction is not updated. Please ignore the color-coding of the wiring diagram.

Recommended operation

1) Should be driven with 600-ohm source impedance.
2) Should not allow DC potential between primary and ground/ secondary and ground of more than 100Vdc.
3) Should be located as far away from the main transformer as possible.
4) Should ground the casing of LCR via mounting bracket.
5) Should mount the LCR inside a steel casing. If external mounting is desired, care should be taken to prevent magnetic flux leakage from the main transformer to the LCR.

(10K version: The 10K version has slightly High Frequency response roll-off when compared to the LCR-600R. This is the nature of the high impedance network.)

LCR 600

LCR-600 has a primary impedance of 600 ohm and a secondary impedance of around 630 ohm, and a forward gain of around -20dB (1KHz). They have been tested at maximum working level of +15.7dBVrms (6.0Vrms) with 600 ohm source impedance. Since the LCR has around 630 ohm secondary impedance, it is not advisable to load the LCR with 600 ohm shunt resistor. This will effectively lower the secondary impedance to around 300 ohm and the primary impedance to 300 ohm. The source of the impedance of 600 ohm will not be able to drive the LCR in this scenario. Therefore it is recommended to load the second of our LCR with shunt resistor of 12K ohm or higher to avoid affecting the impedance and RIAA of the circuit.