Acoustic Image Flex Pre Owner's Manual - Page 7

Browse online or download pdf Owner's Manual for Musical Instrument Amplifier Acoustic Image Flex Pre. Acoustic Image Flex Pre 12 pages.

Print Page

Filter

Effects

On/Off

Phase Inv

Spkr Em

(Optional)

d-Rear Panel

Effects

Prog Select

Headphone

Amp

Filter

Phase Inv

Ch 2

Spkr Em

Effects

jumper

(Optional)

On/Off

Ch 1

Ch 2

H/P

Preamp Out

10 db

Direct Out

Pre/Post

Pad

I/O Buss

Gnd Lift

Master

Level

Output to

Flex Cab

(RJ-45)

Mute

Rate

Level

Rtn

Snd

DC in

1 8V 400mA

Off On

Limiter

Sig/Pwr

Effects Loops

Stereo Out

Interface

Rear Panel

Level

The input level controls the level of the signal at the input stage of the

preamp. The master volume controls the level of the signal at the

output of the preamp (at the input of the Flex Cab or other powered

cabinet). Set the master control at "12 o'clock" and the input level at

zero. The input level should then be used to control the overall output

of the unit. The two controls are provided to allow independent control

of "house" volume and "stage" volume when the unit is used as a stage

monitor with a connection to a house PA. See the discussion under

"Direct Out" below.

If you have an instrument with a particularly "hot" output such as an

active bass guitar and you find that the front end of the preamp is

clipping or being overdriven, a 6 dB gain reduction option is available

via a jumper on the preamp control printed circuit board. How do

access and utilize this option is described in "Jumper Options" section

found on page 15.

Tone

Each tone control has a center detent at the flat position. Experiment

with the controls to achieve the frequency balance that sounds best to

you. In general, small values of boost and cut are best. The Flex Pre

is designed with flat frequency response so only minor corrections

should be required to compensate for room effects or "peaky" pickups

in order to maintain the balanced response desired for acoustic

instrument amplification. To minimize electronic noise, avoid

operating all controls simultaneously at their maximum settings. The

Low control is a shelving-type that affects frequencies below 150 Hz

and with a maximum boost/cut of 12 dB. The Lo Mid control affects

frequencies between 70 Hz and 700 Hz (peak at 250 Hz) and has a

maximum boost/cut of 12 dB. The Hi Mid control affects frequencies

between 700 Hz and 3000 Hz (peak at 1200 Hz) with a maximum

boost/cut of 12 dB. The Hi control is also a shelving-type that affects

frequencies above 3500 Hz with a maximum boost/cut of 12 dB.

Low Cut Filter/Phase Reverse/Speaker Emulation Filter

The Flex Pre has a sweepable low cut filter and phase reverse switch

in each channel. The low cut filter is a variable frequency type that

inserts a 12 dB per octave rolloff at frequencies between 30 and 150

Hz, depending on the position of the control. The low cut filter is used

to reduce the bass output in cases where room location or

instrument/pickup combination results in "boomy" sound. Press the

on/off switch to turn on the filter circuit. Start with the frequency control

fully counterclockwise and gradually turn it clockwise until the desired

effect is achieved. The frequency range of the control is limited in

order to give you more control in the critical low frequency range. As a

result, the effect you hear in normal circumstances may be subtle, but,