PDI-09 “The Junction”
The Junction is the shortest link between your pre-amp, multi-effects unit or guitar amplifier and a
recording-live mixing console. We all know that the sound quality of a guitar amplifier can’t be judged by
ordinary Hi-fi criterion. A guitar amplifier and its speakers are essential to your sound. For the longest time
the only way to amplify this sound was to use the classic approach in a microphone. In recent years there have
been efforts, some more successful than others, to authentically reproduce this sound using “Speaker
Simulators”. To argue about which approach is better is like asking which came first, the chicken or the egg.
That argument could go on and on however, in real life stage and studio applications the direct signal from a
guitar amplifier can make life much easier and produce fantastic results! Two examples: In a recording
situation the guitarist can work directly with the engineer in the control room without being confined to a
sound booth. Live, the acoustics changing from night to night can turn a powerful and crunchy sound from
one night in to mud the next. With a direct signal
both the guitarist and the engineer have a predictable sound
to work with.
Palmer speaker simulators are known to be among the best available today. Even sound purists like
Keith Richards “couldn’t deny that thing” (see Guitar Player interview December ’92) and Joe Satriani, (see
Guitar Player interview May 2000) How did you track the guitars? “We used Palmer Speaker Simulators.
That was the interface for all the amps. We'd go out of the Palmer into a Neve mic pre and then into Pro
Tools”. While Keith was using the older PDI-03 and Joe the newer more improved PGA-04 ADIG-LB both
incorporating a built in load-box, the concept is basically the same with the PDI-09, the only difference being,
the PDI-09 uses your speaker as the load when used at the output of a guitar amplifier. The PDI-09 utilizes
the same tried and true filters that the PDI-03 used in ’92, offering the same quality at a price less than that
of a comparable microphone, all the while functioning without batteries or phantom power. Now, some people
will say that the use of microphones is more versatile however, the PDI-09 will also work at instrument and
line/pre-amp level. Can you imagine micing a pedal-board or pre-amp? We think not! You’d be surprised how
good your favorite stomp box or pre-amp will sound going direct using the PDI-09 as your interface to your
live/recording console.
Connections: Pre-amps, multi-effects units or any devices that output at line level should be connected
to the input of the PDI-09 using a good quality shielded guitar cable. Guitar amplifiers (heads as well as
combos) should be connected to the input of the PDI-09 using a speaker cable and your speaker/speaker
cabinet or load box such as the Palmer “The Sponge” connected to the thru output of the PDI-09 using a
speaker cable as well. * If your amplifier has a variable impedance switch it should be set at the impedance of
your speaker/speaker cabinet and or external load box. CAUTION: If you are using a valve (tube)
amplifier, you MUST have a speaker or equivalent load box connected to the thru jack of the PDI-
09 or considerable damage will occur to the amplifier. Now, using a balanced microphone cable, hook up
the balanced XLR/Cannon output to the microphone input of the mixing console.
The attenuator switch is used to adjust the signal level coming out of the PDI-09. As a rough guide,
0db would be used for line level signals (pre-amps etc.) or instrument level signals such as a pedal board, 15 db
for speaker output signals from lower wattage amps (practice amps) up to 10 watts and 30 db for higher
wattage amplifiers.
