Fender Acoustic Junior, Acoustic Junior Go, and Acoustic SFX II Amplifiers

Owner's Manual

Introduction

Fender's Acoustic Junior, Acoustic Junior Go, and Acoustic SFX II amplifiers deliver full, natural tone for acoustic-electric guitar and microphone, with specially tuned wood cabinets. All three amplifiers feature Bluetooth wireless streaming, studio-quality stereo effects, auxiliary input and headphone output, configurable XLR line outputs, and a USB jack for audio recording.

The Acoustic Junior and Acoustic Junior Go are portable systems ideal for solo performances, featuring two channels with a variety of studio-quality stereo effects. The Acoustic Junior Go offers convenient and environmentally friendly rechargeable battery operation with five hours of full volume from a single charge. With 100 watts of power, an 8” speaker, compression tweeter, a tilt-back kickstand, and light weight, both amps are suitable for rehearsals and performances in various venues.

The Acoustic SFX II amplifier also has a dual-channel design with studio-quality stereo effects and Stereo Field Expansion (SFX) technology, creating a room-filling tonal imagery. It provides 200 watts of power for enhanced guitar and vocals performance.

Image Description: Three Fender acoustic amplifiers are shown. The amplifier on the left is labeled 'Acoustic Junior', the one in the center is 'Acoustic SFX II', and the one on the right is 'Acoustic Junior Go'.

Control Panel

The control panel features:

A. CHANNEL INPUT: Combination jack for XLR and 1/4" inputs. Provides phantom power for XLR mics.
B. VOLUME: Adjusts overall volume level.
C. FX LEVEL: Controls the intensity of the selected effect.
D. FX SELECT: Chooses from various effects like reverb, echo, delay, chorus, and Vibratone.
E. EFFECTS DISPLAY: LEDs indicate the selected effect.
F. POWER INDICATOR: Green light indicates the amplifier is on. For Acoustic Junior Go, color indicates battery charge status (green: sufficient, yellow: low, red: insufficient/faulty).
G. PAIR: Bluetooth pairing button.
H. STEREO SFX (Acoustic SFX II ONLY): Adjusts the Stereo Field Expansion effect.
I. PHASE: Reverses channel polarity to help reduce feedback.
J. LOW, MID, HIGH: Tone controls for bass, midrange, and treble.
K. LOOPER BUTTONS: REC/DUB, PLAY/STOP, UNDO for looper functions.

Rear Panel

L. POWER: On/off switch.
M. IEC POWER INLET: Connects the power cord. For Acoustic Junior Go, connects to AC power to charge the battery.
N. PHONES: 1/8" stereo headphone output, mutes speaker output.
O. AUX IN: 1/8" stereo input for external audio players.
P. BALANCED LINE OUTPUTS: XLR outputs for connecting to external sound systems and recording devices.
Q. MONO/STEREO: Selects mono or stereo output configuration.
R. GROUND LIFT: Helps alleviate unwanted line noise.
S. MONO CONFIGURE: Configures mono outputs for channels 1 and 2.
T. USB PORT: For audio recording. Connect to a computer with recording software.
U. RECOVER: For Fender service personnel only.
V. FIRMWARE UPDATE: Instructions available at support.fender.com.
W. FOOTSWITCH: 1/4" input jack for optional footswitch.

Image Description: A diagram of the rear panel with labels for each connection and control.

Footswitch (Optional MGT-4)

The optional MGT-4 four-button footswitch provides hands-free control. A magnetic overlay is included for application to the footswitch.

X: MODE LEDS: Indicate selected mode (Channel 1, Channel 2, or Looper).
Y: MODE BUTTON/LED: Cycles through modes. In tuner mode, red LED indicates flat pitch.
Z: FUNCTION BUTTON/LED 1: FX BYPASS function. In tuner mode, red LED indicates flat pitch. Also used for Looper REC/DUB.
AA: DISPLAY WINDOW: Shows selected mode and function.
BB: FUNCTION BUTTON/LED 2: Cycles through effects. In tuner mode, red LED indicates sharp pitch. Also used for Looper PLAY/STOP.
CC: FUNCTION BUTTON/LED 3: Controls tap-tempo for time-based effects. Holding activates tuner mode. Red LED indicates sharp pitch. Also used for Looper UNDO.
DD: CENTER TUNER LED: Green LED indicates correct pitch in tuner mode.

Image Description: A diagram of the footswitch with labeled buttons and LEDs.

Looper

The looper allows recording loops up to 90 seconds and overdubbing. Functions can be controlled via the control panel or the footswitch.

Recording: Press REC/DUB button or footswitch to start recording. The LED flashes, and the display shows "REC".
Playback and Overdubbing: Press PLAY/STOP to start playback. Press REC/DUB again to enter overdub mode. The LED flashes, and the display shows "DUB".
Undo Function: Press UNDO to erase the last recorded passage.
Clearing Looper: Press PLAY/STOP to stop, then REC/DUB to start a new recording, effectively clearing the previous one.

Notes on Looper: Recorded audio is not saved when the amplifier is turned off. Looper output is mono. VOLUME control does not affect the looper after recording. The looper can be used on both channels.

Bluetooth

Press and hold PAIR (G) for three seconds to activate pairing mode.
On your external device, enable Bluetooth and select "FENDER ACOUSTIC". Use the device's volume control.
To disconnect, disable Bluetooth on your device or press and hold PAIR (G) for three seconds.

Performance Tip: The amplifier streams audio only from the mobile device. Phone calls will mute the audio stream. To avoid interruptions, enable airplane mode on your device and manually enable Bluetooth.

Specifications

Acoustic Junior, Acoustic Junior Go

Type	Power Requirements	Power Amp Output	Input Impedances	Input Sensitivity	Phantom Power	Tone Controls	Line Out	Speakers	Headphone Output	Battery (Acoustic Junior Go Only)	Footswitch	Dimensions	Weight
PR 5724	155 watts	100 watts into 4Ω (typical 35 watts)	4.7MΩ (instruments), 18.2kΩ (microphones)	40mVrms (instruments), 4mVrms (microphones)	16V (XLR inputs)	Low: ±12db @ 80Hz, Mid: ±12db @ 700Hz, High: ±12db @ 5kHz	Max level: +19.8dBu, Nominal level: +4dBu (2x), Impedance: 600Ω	8" speaker (4Ω) and compression tweeter	140mW into 16Ω/channel	Lithium ion rechargeable. Charge time: 4 hours. Battery life: 5 hours (max volume), 12 hours (moderate volume)	Optional MGT-4 (PN 0994071000)	Width: 15.71" (39.9 cm), Height: 12.02" (30.5 cm), Depth: 9.4" (23.9 cm)	Acoustic Junior: 15.7 lbs. (7.14 kg), Acoustic Junior Go: 17.1 lbs. (7.78 kg)

Acoustic SFX II

Type	Power Requirements	Power Amp Output	Input Impedances	Input Sensitivity	Phantom Power	Tone Controls	Line Out	Speakers	Headphone Output	Footswitch	Dimensions	Weight
PR 5725	300 watts (max)	2 x 100 watts into 4Ω (typical 49 watts)	4.7MΩ (instruments), 18.2kΩ (microphones)	40mVrms (instruments), 4mVrms (microphones)	16V (XLR inputs)	Low: ±12db @ 80Hz, Mid: ±12db @ 700Hz, High: ±12db @ 5kHz	Max level: +19.8dBu, Nominal level: +4dBu (2x), Impedance: 600Ω	Front: 8" speaker (4Ω) and compression tweeter; Side: 6.5" speaker (8Ω)	140mW into 16Ω/channel	Optional MGT-4 (PN 0994071000)	Width: 15.7" (39.9 cm), Height: 19.39" (49.2 cm), Depth: 10.21" (25.9 cm)	22 lbs. (9.98 kg)

Part Numbers

A list of part numbers for different regions is provided for Acoustic Junior, Acoustic Junior Go, and Acoustic SFX II models.

	Fender Acoustic Junior, Acoustic Junior Go, Acoustic SFX II Owner's Manual Comprehensive owner's manual for Fender Acoustic Junior, Acoustic Junior Go, and Acoustic SFX II amplifiers, detailing features, controls, operation, and specifications.
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