MK-300 Guitar/Bass AMP Modeler & Effects Processor

Please read carefully before proceeding

Upon receipt of the product, please calibrate the Pedal 1 first, otherwise Pedal 1 cannot be used normally. For correction, see Pedal 1 setting for Global Settings.

Power supply

Please use a 5V 2A Power adapter to charge the MK-300. Failure to do so will result in damage to the device, fire, or other problems. Unplug the device when not in use or during thunderstorms.

Connections

Always switch off the power supply and other equipment before connecting or disconnecting the device, as this will help to avoid malfunctions and damage to other equipment. Also, always disconnect all connections and power cables before moving the device.

Important Safety Instructions

1. Read these instructions
2. Keep these instructions
3. Heed all warnings
4. Follow all instructions
5. Do not use this apparatus near water
6. Clean only with a dry cloth
7. Make sure to use it away from radio and television sets or other devices that generate magnetic fields to avoid interference
8. Do not use switches and controls by force
9. Do not allow paper, metal and other objects to fall into the machine
10. Do not drop the unit or subject it to shocks or excessive pressure

• High-quality 3.5" LCD screen.
• 4 footswitches for controlling presets and guitar/bass effects.
• 11 effects modules with 360+ different types of effects in total.
• Up to 160 editable user preset slots.
• Editable effects chain allows users to change the order of modules.
• Extensive I/O that provides flexibility for studio, stage, or practice.
• Under the main interface, the functions of the 4 footswitches can be customized and modified.
• 120 Built-in preamp models based on ANN (Audio Neural Net) modelling technology to recreate the feel of an authentic tube amplifier.
• 120 Built-in preamp models, and the DS module also provides 40 overdrive/distortion/fuzz effects.
• 100 high-quality cabinet simulations (1024/2048pts) with support for loading up to third-party impulse response files!
• MIDI port for MIDI IN.
• Global EQ allows user to adjust the tone quickly according to different audio setups.
• Integrated 300-second looper can be set to Tail mode or Head mode.
• 128 drum machine variations to choose from.
• The 4 footswitches allows user to set the footswitch as the on/off switch or tap tempo switch.
• The footswitch expansion function can set 4 footswitches to "use foot to Save", "preset ±4", "preset volume ±5", "Pedal 1 A/B", "Pedal 2 A/B", etc.
• Battery life: About 10+ hours.
• This unit can be used as an audio interface with a cellphone, use the accessory recording cable to connect the cellphone, then enter any video/audio recording APP for direct recording.
• USB jack: Use to charge the battery/The MK-300 can be a sound card of computer/ Computer software can be connected for interactive data transmission/ Use USB MIDI function/ Firmware updates or factory Settings can be restored in the computer software /Third-party IR files (CAB module) and AMP and DS files can be imported/ OTG recording.
• Designers provide users with a super convenient footswitches-stepping mode called the "PRESET LIST". In this mode, 4 footswitches represent 4 presets, 4 presets as a BANK, with the left two footswitches for BANK- and the right two footswitches for BANK+.
• The color of each preset footswitch-light can be customized.
• This machine provides users with 3 convenient parameter knobs, which can be customized according to different presets.
• Wireless BT function, support for BT music and for APP data transfer.
• 44100HZ 24Bit high sampling rate digital signal processor to provide you with a nuanced sound.
• Free download of computer software or mobile APP from our official channels to provide users with more ways of operation and management.
• RE-AMP mode, you can send audio tracks from your computer to be processed and have effects added by the MK-300. For example, a non-processed guitar track could be played through the MK-300 and have amp models and cabs added.

Control Descriptions

• 1 PARA: Rotate or press to navigate and select from options. You can use it to select preset, select and confirm the item on the screen, move modules or edit parameters. ? Tips: When there are two or more dots icon showing on the screen, it means that under the current item, there are not only 3 parameters that can be adjusted. You can use the PARA button to click the current item again to turn the page of the parameter, and then you can use the three dials under the screen to adjust more parameters.
• 2 3.5" LCD screen: Display the states and detailed information.
• 3 MASTER: Control the output volume.
• 4 KNOB1 Custom knob: You can go to the CTRL interface to customize the setting function, which follows the preset. In factory condition, the function is set to the LEVEL-parameter adjustment of the AMP module.
• 5 KNOB2 Custom knob: In factory condition, the function is set to the GAIN-parameter adjustment of the AMP module.
• 6 KNOB3 Custom knob: In factory condition, the function is set to the MIDDLE-parameter adjustment of the AMP module.
• 7 SAVE illuminated Button: Press once to enter the save screen. When in the saving screen, press again to save and exit. On the save screen, hold the PARA key to switch to the SWAP function. On any screen, hold the SAVE button to save the preset without switching the current screen. In addition, the SAVE button light blinks to indicate whether the current default parameter has been changed. If the light blinks, it indicates that the parameter has been changed. Before you switch the preset, you'd better save the parameter in time to avoid data loss.
• 8 HOME illuminated Button: Click to go to the Main Screen. Click again to go to the STOMP Screen. Hold to turn on the Tuner. After turning on the tuner, the button light will be steady on. The "Main Display Screen" is the home page displayed right after the power is turned on. You can directly see the key information and settings of the current Preset, you can also know about battery conditions and other information and so on.
• STOMP interface: On the stomp interface, you can view the connection order and on/off states of 11 Modules, or use PARA to move the order. The function of the 4 footswitches under the STOMP interface is designed: the left two footswitches are used to switch the presets, and the right two are used to select and turn on/off the module.
• DRUM illuminated Button: Click to play or stop the drum machine immediately, and hold to enter the drum machine screen. The button light will be constantly on when the drum machine is playing.
• GLOB illuminated Button/BT switch Button: Click to access the global operation screen, and hold to turn BT on/off. When the light is steady on, it indicates that BT is successfully connected. When the light is flashing, it indicates that BT is enabled but not connected. When the light is off, it indicates that BT is turned off.
• 10 effects modules illuminated Button: These buttons show the on/off state of the 10 effect Modules. If the button is off, the effect is not enabled. If the button is on, the effect is started. If all 10 buttons are Off, the MK-300 is in Bypass state. Click to enter the Edit Settings Menu of Module, then click again to turn on/off Module. At any time, you can hold the button to quickly turn on/off Module. When the Edit Settings Menu is displayed on the screen, you can use the PARA and three dials below the screen to adjust any of the effects and parameters on the screen.
• When the Edit Settings Menu is displayed on the screen, the function of 4 footswitches has been set. The first and second footswitches are used to switch the Presets, use the third to turn the current module on/off, the fourth footswitch in some modules is non-functional. In some modules that require the effect of tapping-speed, the fourth footswitch can also be used to TAP.
• LOOPER illuminated Button.
• CTRL illuminated Button/The switch-button of VOL module in effects chain (The 11th module): Click this button to enter the ctrl interface. Hold this button to open the VOL module and enable or disable the VOL module functions. These functions in the CTRL interface are stored independently along with the preset, providing Pedal 1, Pedal 2, Knob 1, Knob 2, Knob 3, FS 1, FS 2, Ctrl A, Ctrl B.
• Functions of Pedal 1 and Pedal 2: Each pedal can store parameters of two states A/B, A-state can be set to control one of the parameters of one module, and pedal extremum can also be freely selected. The same can be done for B-state.
• Function of FS1, FS2, Ctrl A, Ctrl B: These are functions of Click or Hold the single footswitch when the screen is in the HOME interface. The table below describes the meaning of all the functions. (For convenience and simplicity, only the function of a single footswitch can be customized at preset. The function of combination footswitches is already defined by the designer and does not support modification.)

Footswitch Functions:

Function	Description
Module ctrl	Used to enable/disable one or more effect modules
Drum PLAY	Used to start/stop the drum machine
Looper	Play LOOP music or start recording
Looper stop	Stop Looper
tap	Adjust the current Preset bpm
tuner	Open the tuner
Preset list	Enter the Preset list interface
save	Used to save the current preset
Preset-1 / Preset+1	Used to switch to the previous or next preset
Preset-4 / Preset+4	Switch to the fourth preset above/below
Preset vol-5 / Preset vol+5	Adjust the volume of the current preset
Drum Preset + /Drum Preset- BPM- BPM+	Used to change the rhythm pattern of the drum machine / Adjust the current Preset bpm
Pedal 1 A/B / Pedal 2 A/B	Switch pedal A/B states
None	Non-function

There are three parameter dials for the Follow Screen function: Dial1, Dial2, and Dial3.

Preset UP/DOWN footswitch (Fs1 and Fs2): Can be customized in the ctrl interface. In factory default, they switch Presets up/down. Long-pressing them jumps to the fourth preset above or below. In the drum interface, they adjust speed. In Stomp/Module screens, holding them preselects/loads/cancels presets.

CONTROL A/B footswitch: Can be customized in the ctrl interface. In factory default, they switch Preset VOL up/down. Long-pressing them toggles Pedal 1 A/B states or saves the current preset. CTRL A can turn modules on/off. CTRL B selects modules in STOMP screen. In MOD/DLY/FX, CTRL B adjusts effect speed. In DRUM, they control drum machine on/off and TAP. In LOOPER, functions vary by state.

Expression pedal 1: Can be set as volume, wah, or other parameter control. Can be set to A/B states. Stepping down hard switches states. Parameters of Pedal1 A/B can be customized in CTRL interface, and states can be changed by footswitches.

? Tip: Upon receipt, calibrate Pedal 1 first. See Global Settings for correction. Factory presets often use Pedal 1 for VOL module parameters (A-state), with some for WAH or other effects.

Connection Ports

• 1 PEDAL 2: 1/4" stereo audio input jack for external expression pedal (1/4" TRS cable). Pedal can be set to A/B states, adjustable via CTRL interface. Footswitches can change A/B states. ? Suggested: Use footswitches for A/B state switching. Disable "A/B Convert" in GLOBAL screen to set max/min values without press function. This avoids calibration issues with third-party pedals. Use Ctrl A or Ctrl B footswitches for A/B state switching.
• 2 INPUT: 1/4" mono audio input jack for guitar or output of another pedal.
• 3 MIDI: 5-pin MIDI port, MIDI IN.
• 4 XLR OUT: XLR stereo audio output for balanced signal (connect to L for mono setup).
• 5 GND/LIFT: Ground and lift switch for XLR output.
• 6 Phone recording jack: Supports mobile phone recording or playback to the earphone jack.
• 7 PHONES: 1/8" stereo earphone output jack.
• 8 OUTPUT: 1/4" stereo audio output jack for unbalanced signal (connect to L(MONO) for mono setup).
• USB jack: For charging battery, computer connection (data transmission, USB MIDI, firmware updates, factory reset, IR/AMP/DS file import), OTG recording. ? Can be used as a cellphone audio interface with a separate OTG converter and USB cable for direct recording via APP.
• Charging indicator: Off during normal use. Red during charging, changes color when fully charged.
• 11 Power Switch: Toggles the unit on/off.

Main Display Screen

The home page displayed after power-on. Shows key information and settings of the current preset.

• Preset number: 1-160 total. 1-60 for electric guitar, 61-80 for bass, 81-160 no effect. PARA knob switches presets. Factory reset available for first 80 or all 160 presets via computer software.
• Preset name.
• INPUT volume monitor.
• Mixed output volume monitor.
• CPU condition: Warning if load rate exceeds 90%, may cause noise.
• Ctrl A or Ctrl B: Single click functions on this screen. Long-press functions require entering the CTRL interface.
• Pedal 1 and Pedal 2: Show pedal states (blue for A, red for B).
• Preset BPM: Adjustable range 40-240 BPM.
• Battery display icon.
• Fast adjusting Dials (Dial 1, 2, 3): Show current function (e.g., Preset volume, BPM, PAN). Dial 3 PAN at -100 outputs only to the left channel.
• Looper display bar: Appears if audio is in the Looper.

TUNER

Long press the first and second footswitches on the home screen, or hold the HOME button, to enter tuning mode.

The screen displays note name, string tuning accuracy (left=flat, right=sharp), volume (Dial 1, 0-100), and standard A frequency (Dial 3, 430Hz-450Hz, default 440Hz). Effect chain is bypassed, hearing dry guitar sound. Other footswitches exit tuning mode.

LOOPER

Press the LOOPER button to enter the Looper screen. Long press LOOPER to start/stop recording and save. If audio exists, long press LOOPER to play/stop audio. In the LOOP interface, the LOOPER button functions like the third footswitch. Right two footswitches on the home screen also access the Looper screen.

On the Looper screen, short pressing the left two footswitches returns to the main screen; pressing one switches presets. Rotating PARA has no effect but cycles dial display functions. Footswitch display shows real-time functions (short/long press). Looper display bar shows recording (red), playing (green), or overdubbing (yellow). Long press the rightmost footswitch to switch to the drum machine interface.

Looper Dial Functions:

1. REC VOL: Changes looper recording volume.
2. PLAY VOL: Changes looper playback volume.
3. AUTO REC: Turns auto-recording on/off. ONCE for single recording, HOLD for multiple.
4. AUTO GATE: Auto-recording threshold. Higher threshold reduces triggers.
5. POS: Looper position in effects chain ("HEAD" for dry sound, "TAIL" for effected sound).
6. DRUM SYNC: Starts drum and loop simultaneously, aligning them. ON1/ON2 differ in whether the drum pauses with the loop.

DRUM

Long press the DRUM button to enter the drum machine interface; short press plays/stops the drum machine. The DRUM button light is on when playing, off when stopped. Long press the right two footswitches on the main screen to enter the DRUM screen.

In the drum interface, PARA switches genres/styles (128 drum presets). Left two footswitches adjust Drum BPM. Short press left two footswitches returns to main screen. Long press rightmost CTRL B footswitch switches to LOOPER interface. On the Drum screen, CTRL A plays/stops the drum; the fourth footswitch is for TAP tempo.

Drum Dial Functions:

• Dial 1: Changes drum volume (0-100).
• Dial 2: Changes drum tempo (40-240 BPM).
• Dial 3: Synchronizes drum tempo with preset tempo.

The order of the 11 effects modules can be customized. The LOOP position can be set to Tail or Head.

The chain consists of: WAH, FX, GATE, DS, AMP, CAB, EQ, MOD, DLY, REV, VOL, LOOP, DRUM.

Connections include: IN, BT, USB, USB, XLR OUT, OUT.

Global Settings affect the entire MK-300 state and do not change with presets. Changes take effect immediately.

Pedal 1 and Pedal 2

1.A/B Convert:

• Off: No third calibration step needed, only max/min values. No press value. Can use 4 custom footswitches for A/B state switching.
• On: Pedal can use press function to switch A/B states. ? Tip: When calibrating, avoid similar forces for second/third steps to prevent calibration failure.

2.Sync:

• Off (Factory Default): Machine does not read pedal value upon preset change unless pedal is moved. Ensures presets are not affected by pedal position.
• On: Machine immediately reads pedal value upon preset change. Useful when using the pedal as a controller for all preset VOL volumes or fixed parameters.

3.Pedal State: Not a global feature. A convenient toggle for preset A/B states.

Other

• 1.RCH: Three gears. Gear 1: Left/right channel output is the same. Gear 2: Left=dry, Right=wet (wet record dry). Gear 3: Left=CAB effect, Right=no CAB effect.
• 2.USB Audio: Three gears. Gear 1: Records accompaniment and instrument sound. Gear 2: Loopback function. Gear 3: RE-AMP mode (process computer audio tracks through MK-300). ? Loopback is common for sound cards. "Nor" gear records computer/phone music and instrument sound together (mixed). "No" gear records only IN interface and 13 modules, useful for sub-track recording.
• 3.BT&USB VOL: Adjusts BT and USB input volume.
• 4.Pedal 1 Toe Switch and Pedal 2 Toe Switch: Three gears. Gear 1: Pedal switch state doesn't affect module on/off. Gear 2 (Resume): Effect turns on when pedal switches to it, returns to original state when switching away. Gear 3 (Disable): Effect turns on when pedal switches to it, turns off when switching away.
• BT: Turn BT on/off (same as long-pressing GLOB button).

Global EQ

Controls the global equalizer to change the overall tone feel.

Connect MK-300 to PC/Mac to use free MK-300 software for tone adjustment, preset import/export, factory reset, firmware upgrade, loading 3rd party IRs, etc.

APP Usage Tips:

Ensure BT is on for both cellphone and MK-300. Run the APP, click the "≡" button, select "Current Device", choose "MK-300", then scan nearby devices to connect.

We will continuously improve our products and reserve the right to modify functions and specifications without prior notice. Please confirm product functions and specifications with your local distributor before purchase. Product images and colors may differ from the physical product due to lighting and screen settings.

• Dynamic Range: 117dB
• Working current: 350mA
• Sample rate: 44.1KHz/24bit
• Module: 11
• Total effects: 320+
• Preset Memory: 160 Preset slots, 80 Factory Presets
• Looper: Maximum 300 seconds of record time
• Drum Machine: 128 drum presets
• MIDI: 5-pin MIDI connectors or BT MIDI or USB-C
• Analog Input Connections: Guitar Input: 1/4" Unbalanced (TS)
• Analog Output Connections: L/R Unbalanced Outputs: 1/4" TS jacks, L/R Balanced Outputs: XLR jacks, Earphone Output: 1/8" Stereo (TRS), Phone record Output: 1/8" Stereo (TRS)
• Digital Connections: USB Port: USB 2.0 Type-C, USB audio, USB MIDI, LOOPBACK ON/OFF, RE-AMP support.
• Size and weight: Dimensions: 330mm(L) x 175mm(W) x 55mm(H), Unit Weight: Approx. 1460 kg
• Battery life (10h): Requirements: USB 5V 2A, Capacity: 5000mAh, Model: 105080, Voltage: 3.7V, Charging current limit: 1A
• BT Music: Support
• Software support: WINDOWS, MAC, IOS, Android
• Third-party DS and AMP timbre loading: Support
• IR processing (CAB module): 44.1K/24Bit Mono WAV files, 1024/2048 sampling points
• Built-in pedal: 1
• External pedal jack: 1
• Attachment: USB cable, User manual, Recording cable.
• Revision: 2024-12-26

Changes or modifications not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment. This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
• Consult the dealer or an experienced radio/TV technician for help.

FCC Radiation Exposure Statement

The device has been evaluated to meet general RF exposure requirement. The device can be used in portable exposure condition without restriction.

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions:

1. This device may not cause harmful interference.
2. This device must accept any interference received, including interference that may cause undesired operation.