SOWTER AUDIO TRANSFORMERS
1:20 PHONO CARTRIDGE TRANSFORMER

Sowter Type 1990
Configurable 1:10 or 1:20  Transformer  3 to 50 ohm Phono Cartridges - BUY

1990 frequency response
Style f leads

APPLICATION

For matching a moving coil phono cartridge to balanced or single sided solid state or valve pre-amplifier. Ensures appropriate loading of the cartridge and correct matching to pre-amplifier. Ideal for use with low output cartridges with a dc resistance in the range 1 to 5 ohms. 1:20) and 1 to 40 Ohms (1:10 configuration). The loading seen by the cartridge may be adjusted by means of a secondary load resistor. For more information CLICK HERE

Two transformers are required for a stereo system. For 1:20 operation connect the primary windings in parallel. (Grey to Red and Orange to White) For 1:10 operation connect the primary windings in series (Orange to Red). The Black (ground) lead is normally connected to the signal ground of the amplifier. You may need to experiment with different connection points to eliminate hum.

FEATURES

Mumetal (76%Nickel) laminated core for minimal harmonic distortion and exceptional bandwidth. 4 separate electrostatic screens for rejection of hum and noise in the cable connecting between the cartridge and transformer. Multiple interleaved windings ensuring exceptionally good bandwidth with a wide range of cartridge impedances. As shown above the bandwidth improves with lower cartridge resistances. The high bandwidth and very low phase shift ensures excellent transient response. Mumetal can for magnetic shielding. Available with colour coded leads or international octal plug for a small extra charge. Available wound with OCC wire as an option. This transformer replaces types 7136 and 9575. Available with threaded grommet (style e), Octal base (style g) and side leads (style f). To see dimensions etc CLICK HERE
RATIO 1+1+20
PRIMARY INDUCTANCE (primaries in series 1:10 ratio) 2H approx
DC Resistance (primary) 2.4 Ohms approx
DC Resistance (secondary) 1500 Ohms approx
FREQUENCY RESPONSE 40 Ohm source 10 KOhm load. (-3 dB points) 5Hz to 100 KHz
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