Palmer PDI-03 8 Ohm Speaker Simulator. This unit is #1 of 2 that were in my touring rack from the late 80's 90's & 2000's and until recently. It's in great condition considering its age and although the Line Out knob was replaced some time ago by a standard amp style knob due to loss of the original, it functions perfectly and sounds fantastic.

The Palmer PDI-03 Speaker Simulator is a legendary DI and load box that allows guitarists to capture the tone of a miked, cranked tube amplifier directly to a mixing board or interface without using a physical cabinet. The PDI-03 was a staple of 1980s and 1990s rack-based guitar setups. A definitive list of artists who have relied on the unit includes:

Eddie Van Halen Joe Satriani Keith Richards John Ashton Mark Knopfler Mike Campbell Joe Bonamassa Toni Iomi Josh Homme Johnny Marr Billy Corgan Dan Auerbach to name just a few.

It's a single-space rackmount unit that combines a signal splitter, DI box and power soak with an eight-ohm load circuit. Special filters within the PDI-03 are designed to provide carefully contoured equalisation to the amp signal, simulating the sound of a guitar amp through a cabinet.

Usable with or without a speaker cabinet, the signal is taken from your amp's speaker output into a rear jack and can be passed out unattenuated to a cab via an adjacent thru jack. A further four line out jacks, with output controlled from a front panel knob, are available on the rear panel to send an unfiltered (non speaker-emulated) signal to effects units or elsewhere.

The speaker-emulated signal exits either via a balanced XLR socket or an unbalanced jack and is tailored by three front panel controls: a volume knob and two three-way switches, which used together provide a range of speaker-emulated tones.

One offers variations on low-end tone - deep, which represents a 4 x 12 closed-back cab, and flat, a 2 x 12 open-backed combo-style speaker. The other offers high-end tonal variations with normal, mellow and bright options.