Gibson Les Paul 1970 Les Paul catalogue. Page 11. Right hand page of a double spread on the Gibson Les Paul LP1 amplifier and LP2 cabinet. Continued from page 10.
This page also details the low impedance transformer required for normal operation with a high impedance amplifier.
When a low impedance instrument is not being used with the LP-12 amplifier, you must use a Gibson low-to-high impedance transformer cord with your conventional high impedance amplifier. If you do not use the cord, your instrument will not function properly.
Not using the transformer results in the guitar outputting a lower signal level - if an amp has enough headroom, it may be possible to simply turn it up to compensate for the lower input signal.