Fender Acoustic Junior, Acoustic Junior Go, Acoustic SFX II

This document provides user instructions and technical specifications for the Fender Acoustic Junior, Acoustic Junior Go, and Acoustic SFX II amplifiers.

Introduction

The Fender Acoustic Junior, Acoustic Junior Go, and Acoustic SFX II amplifiers deliver full, natural tone for acoustic guitar and microphone, housed in specially tuned wooden cabinets. All three amplifiers feature Bluetooth wireless streaming, studio-quality stereo effects, an auxiliary input and output, headphone output, configurable XLR line outputs, a USB port for audio recording, and more.

Ideal portable systems for solo performances, the Acoustic Junior and Acoustic Junior Go amplifiers feature two channels, each with a suite of studio-quality stereo effects. The Acoustic Junior Go offers convenient and eco-friendly operation with a rechargeable battery providing five hours of full volume on a single charge. With 100W of power, an 8-inch speaker, a compression tweeter, a convenient tilt-back stand, and light weight, both amplifiers are ideal for great guitar and vocal rehearsals and performances in a variety of venues.

For solo performances or on stage with a band, the Acoustic SFX II amplifier also features a two-channel design with studio-quality stereo effects and the amazing Stereo Field Expansion (SFX) technology, which goes beyond stereo for room-filling soundscapes that envelop the listener in a rich acoustic experience. It increases the power to 200 watts for perfect guitar and vocal power and performance.

Pictured from left to right: Acoustic Junior, Acoustic SFX II, Acoustic Junior Go.

Control Panel

The control panel features the following:

A. CHANNEL INPUT: Combo jack (XLR/1/4") for instrument or microphone. XLR provides phantom power for condenser mics (avoid ribbon mics).
B. VOLUME: Master volume control for all outputs.
C. FX LEVEL: Adjusts the intensity of the selected effect.
D. FX SELECT: Chooses from various effects like Room, Hall, Echo, Delay, Chorus, Vibratone, DLY+CHO, DLY+REV. An optional footswitch can control delay time.
E. FX DISPLAY: LEDs indicate the active effect settings for each channel.
F. POWER INDICATOR: Green light indicates the amplifier is powered on. For the Acoustic Junior Go, it also indicates battery status (Green: full, Yellow: low, Red: insufficient/faulty). It blinks while charging and stays solid green when charging is complete.
G. PAIR: Bluetooth pairing button.
H. STEREO SFX (SFX II ONLY): Controls the width of the Stereo Field Expansion effect for a 360-degree soundstage. Requires FX Select and FX Level to be engaged.
I. PHASE: Inverts channel polarity to reduce feedback.
J. TONE CONTROLS (LOW, MID, HIGH): Adjusts bass, midrange, and treble frequencies.
K. LOOPER BUTTONS (RECORD/DUB, PLAY/STOP, UNDO): Controls for looper functions.

Note: Features marked with an asterisk (*) are identical on the opposite channel. Refer to the Footswitch section for additional features.

Rear Panel

The rear panel includes the following connections and controls:

L. POWER: On/Off switch.
M. IEC POWER INPUT: Connects to AC power.
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: Balanced XLR outputs for connecting to external sound systems or recording devices.
Q. MONO/STEREO: Selects stereo (Out) or mono (In) output configuration.
R. GROUND LIFT: Switches between grounded (Out) and lifted (In) operation to reduce line noise.
S. MONO CONFIGURATION: Works with the MONO/STEREO switch to sum channels or provide separate outputs.
T. USB PORT: For audio recording to a computer. Visit https://support.fender.com for setup assistance.
U. RECOVER: For Fender service personnel use only.
V. FIRMWARE UPDATE: Instructions available at https://support.fender.com.
W. FOOTSWITCH: 1/4" input for optional MGT-4 footswitch.

Footswitch

A magnetic overlay is included for the optional MGT-4 footswitch to adapt it for use with these amplifiers.

X. MODE LEDs: Indicate Channel 1, Channel 2, or Looper mode.
Y. MODE BUTTON/LED: Cycles through modes. In tuner mode, the red LED indicates pitch flattening.
Z. FUNCTION BUTTON/LED 1: FX Bypass. In tuner mode, indicates pitch sharpening. Also REC/DUB for looper.
AA. DISPLAY WINDOW: Shows current mode and function.
BB. FUNCTION BUTTON/LED 2: FX Select. Cycles through effects. In tuner mode, indicates pitch sharpening. Also PLAY/STOP for looper.
CC. FUNCTION BUTTON/LED 3: Tap Tempo for time-based effects. Hold to enter tuner mode. Also UNDO for looper.
DD. CENTRAL TUNER LED: Lights green when correct pitch is achieved in tuner mode.

Looper

The Looper mode allows recording loops up to 90 seconds with overdubbing. Only the last overdub can be undone.

Recording: Press REC/DUB (control panel or footswitch) or Y (Looper mode) then Z (REC/DUB) on footswitch. Display shows "REC". Play for up to 90 seconds.
Playback/Overdubbing: Press PLAY/STOP (control panel or footswitch). Display shows "PLA". Press PLAY/STOP again to stop ("STP"). Press REC/DUB again to enter overdub mode ("DUB").
Undo: Press UNDO (control panel or footswitch) during recording/playback/stop of the first loop to erase it. After overdubs, UNDO only affects the last overdub.
Clearing Looper: Stop playback, then press REC/DUB to start a new recording, clearing the previous content.

Looper Notes: Recorded audio is not saved when the amplifier is powered off. Looper output is mono. The VOLUME (B) control does not affect the looper after recording. The looper can use both channels, which are mixed equally.

Bluetooth

Pairing and connecting your device:

Press and hold the PAIR button (G) for three seconds to activate pairing mode. The PAIR button blinks and then stays lit when connected. The amplifier auto-pairs with the last connected device.
Enable Bluetooth on your external device, scan for "FENDER ACOUSTIC," and connect. Use the external device's volume control.
To disconnect or pair with another device, disable Bluetooth on your mobile device or press and hold PAIR (G) for three seconds.

Performance Tip: To avoid interruptions from phone calls, enable airplane mode on your mobile device and manually enable Bluetooth.

Technical Specifications

Feature	Acoustic Junior, Acoustic Junior Go	Acoustic SFX II
Type	PR 5724	PR 5725
Power Requirements	155W	300W (max)
Output Power	100W @ 4Ω (Junior)	2 x 100W @ 4Ω
Typical Power Consumption	N/A	49W (typical)
Input Impedance	4.7 MΩ (instrument) 18.2 kΩ (mic) 18kΩ (aux)	4.7 MΩ (instrument) 18.2 kΩ (mic) 18kΩ (aux)
Input Sensitivity	40 mVrms (instrument) 4 mVrms (mic) 900 mVrms (aux)	40 mVrms (instrument) 4 mVrms (mic) 900 mVrms (aux)
Phantom Power	16V (XLR input)	16V (XLR input)
Tone Controls	Low: ±12dB @ 80Hz Mid: ±12dB @ 700Hz High: ±12dB @ 5kHz (shelf)	Low: ±12dB @ 80Hz Mid: ±12dB @ 700Hz High: ±12dB @ 5kHz (shelf)
Reverb Max Level	+19.8dBu	+19.8dBu
Speakers	8" speaker (4Ω) and compression tweeter	Front: 8" speaker (4Ω) and compression tweeter Side: 6.5" speaker (8Ω)
Headphone Output	140mW @ 16Ω/channel	140mW @ 16Ω/channel
Battery (Junior Go Only)	Rechargeable Lithium-ion Charge Time: 4 hours Battery Life: 5 hours (heavy use) Capacity >70% after 500 cycles	N/A
Footswitch	MGT-4 (optional, PN 0994071000)	MGT-4 (optional, PN 0994071000)
Dimensions (W x H x D)	15.71" (39.9 cm) x 12.02" (30.5 cm) x 9.4" (23.9 cm)	15.7" (39.9 cm) x 19.39" (49.2 cm) x 10.21" (25.9 cm)
Weight	Acoustic Junior: 15.7 lbs (7.14 kg) Acoustic Junior Go: 17.1 lbs (7.78 kg)	22 lbs (9.98 kg)

Product specifications are subject to change without notice.

Part Numbers / References

Various part numbers are listed for different regions and voltage configurations for the Acoustic Junior, Acoustic Junior Go, and Acoustic SFX II models.

Manufacturer Information

Fender Musical Instruments Corp.
311 Cessna Circle
Corona, Calif. 92880 USA

Imported by: Fender Ventas de México, S. de RL de CV
Calle Huerta #279, Int. A. pukovnik El Naranjo. CP 22785. Ensenada, Baja California, México.
RFC: FVM-140508-CI0

Customer Service: 01(800) 7887395, 01(800) 7887396, 01(800) 7889433

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