Ada MICROCAB I Owner's Manual page 5

ADA Microcab I owners manual version 1
HOW TO GET THE BEST TONE WITH YOUR MICROCAB
First, get your best tone using your whole regular rig, including your speaker cabinets! Now,
to capture that tone to tape, insert the MICROCAB between your preamp and your power
amp. Remember, you can listen to your regular speaker tone by using the MICROCAB's
pass-thru jacks on the rear panel. These are hard-wired directly off the input jacks.
Try the variety of cabinet configuration tone settings offered by the MICROCAB to obtain the
sound you want, starting with the exact speaker configuration that you are using. Use the HI
BALANCE tone control on the front panel to adjust the brightness, and the THUMP control to
boost or cut the amount of low-frequency resonance, especially if you are emulating a sealed
cabinet. The MICROCAB offers emulations of 12-inch speakers in 1, 2, and 4-speaker
configurations, in both open-back and sealed enclosures. You can also use the VINTAGE
settings for a darker-sounding tone coloration.
Note: When using headphones with the MICROCAB, you may want to adjust HI BALANCE
downward to compensate for high frequency emphasis found in most headphones.
WHAT THE MICROCAB DOES
The ADA MICROCAB is a tone-shaping device designed to emulate the complex physical
and psychoacoustic effects that make up the unique "live" sound of a close-miked guitar
cabinet. In the early days of recording, "distant" or "ambient" miking—often using a single
room microphone for the entire performance—was the standard; the distinctly modern
technique of close-miking adds more immediacy and control over the instrument voice.
There are some "competitive" products on the market, simple band pass filters, cutting highs
and some lows. Such speaker emulators can sound "muddy," that is, lacking in definition or
"presence." Only the ADA MICROCAB offers true emulation of a classic "close-miked"
speaker cabinet. The MICROCAB delivers improved voicing, brilliant presence, "in your face"
high-midrange sizzle (1.2-1.5 KHz), and the characteristic "thump" (low frequency
resonance) found in classic guitar cabinets. Moreover, the ADA MICROCAB offers you the
versatility of having a variety of speaker cabinet tones at your fingertips in one compact
single-space rack device.
The purpose of calling the ADA MICROCAB a "miked" guitar cabinet emulator is to
distinguish it by features that account for the microphone in the audio path. As the number of
speakers is increased in a miked cabinet, the number of signal paths to the microphone
increases, adding a comb filter effect to the guitar sound on tape. The sound from these
"paths" have a different distance to travel to get to the microphone element and therefore
when they combine they produce cancellations and reinforcements across the frequency
spectrum. This is one of the sources of the "complex" feel of the close-miked guitar cabinet.
Comb Filter
The "thump" or low frequency resonance in guitar cabinets mentioned above is perhaps the
most powerful characteristic in live amplified guitar performance. Most cabinets are like the 4
x 12 (an array of four 12" speakers as is used in British-style stack-type cabinets) with no
ports (holes as in hifi loudspeaker enclosures) and no open backs. The frequency produced
by such a speaker cabinet array is around 200 Hz (abbr. for Hertz or cycles per second),
which resonates with the human chest cavity. The ADA MICROCAB is unique it its ability to
reproduce this power and feel of the live performance directly to tape!
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