The audio signal path of the AR-133 is an enhanced design based upon the long established BSS AR-116, now regarded by many as a reference unit. The sound quality, particularly on acoustic guitar and bass guitar pick-ups, is recognised as outstanding. The uses, however, are not limited to guitars or keyboards. The AR-133 is suitable for use whenever it is critical to match levels and impedances, sources need isolation or long cables are used.

Features:
- Switchable input attenuation 0dB for guitar-type pickups -20dB for line level signals -40dB for speaker feeds
- Matches the level and impedance with unity gain without loading the source
- Can drive signals up long cable lengths
- Powered from console phantom power or internal battery
- Automatic switchover to battery if phantom power fails
- Parallel Link Jack output to feed amplifiers directly
- Parallel XLR input for converting unbalanced outputs to balanced lines