Linear Tube Audio ZOTL40 Reference, User Manual, Page: 6 / 8

Operating Modes
MONO/STEREO Switch: Two ZOTL40 Reference amplifiers can be
operated as mono-blocks, which deliver approximately 1.7x the
power into 8 Ohms. To operate in the mono mode:
1. Set the MONO/STEREO switch to Mono.
2. Use the left RCA input.
3. Using jumpers cables, bridge the two positive (red)
speaker terminals together and bridge the two
negative (black) speaker terminals together. DO NOT
CONNECT the red and black speaker output terminals
together, as this shorts the amplifier. Once bridged,
either positive terminal and either negative terminal
can be used to connect your speaker.
Protection Circuit
The amplifier is DC-coupled and has a protection circuit that will
shut down the amplifier internally if certain parameters are sensed.
The protection circuit can also be triggered by over-driving the
amplifier. If the amplifier goes into protection bright, white LEDs will
light up on the audio board, which should be visible through the
top of the case on the left side (if you are looking at the front of
the amp). More obviously, if the amplifier goes into protection it will
stop playing when turned on. Be sure to check that it is the
amplifier causing the problem and not another component.
To reset the circuit, simply turn it off, wait a few minutes, and turn
the amplifier back on. If the amplifier does not reset successfully,
or goes into protection again immediately, try waiting an hour
before turning back on. If the amp is still unresponsive, or if the
protection circuit is continuously triggered, contact us.