Lundahl LL156X-3FX3MX Audio transformer

The XLR inline transformer unit LL156X is designed for breaking up ground loops and for balanced-to-unbalanced conversion in mobile or stationary audio systems. The unit is magnetically shielded and contains a high impedance input transformer LL1565, with LF saturation above +22 dBU, 40 Hz. The two ends of the unit are galvanically isolated from each other.

The LL156X is available in four versions:

LL156X-3FXNP2C   Female XLR connector to 2-pole ‘A’-gauge 1/4” jack plug

LL156X-PHF3MX    Female Phono (RCA) connector to male XLR connector

LL156X-3FXPHM    Female XLR connector to Phono (RCA) male

LL156X-3FX3MX     Female XLR connector to male XLR connector

Characteristics of built in transformer LL1565

• Static resistance of primary:                                                                        1.6 k ohms
• Static resistance of secondary:                                                                     1.3 k ohms
• Core:                                                                                                               Amorphous strip core
• Max level:                                                                                                       +22 dBU @ 40 Hz
• No-load impedance (@20 dBU, 50Hz):                                                        220 k ohms typically
• Frequency response @ 0 dBU (source 600 ohms, load 10k ohms) :            4 Hz - 100 kHz +/- 0.5 dB
• Distortion (THD, source 600 ohms)                                                              < 0.2 % @ 50 Hz, 0 - 22 dBU
• Loss across transformer, load 10k ohms / 100k ohms                                 2.2 dB / 0.3 dB
• Isolation between windings:                                                                         1 kV