The Microtubes® 500 is a 500W amplifier equipped with an all analog solid state preamplifier and a Class D Power Module. On the top row, you will find the clean section which is the foundation of your tone. It features a Gain control and an active 4 band EQ: along with Low and Treble controls, you will find Low Mids and Hi Mids controls, each knob with their own 2-way frequency switch. On the bottom row, you will find the Microtubes Engine®, an extra channel that will bring your clean tone to the next level by helping you cut through the mix while adding anything from subtle, tube-like, harmonics and natural compression to obliterating distortion.
Front Panel Features
- Input: Connect your instrument via a standard ¼” mono cable.
- Passive/Active: Switch from passive to active mode. Some active basses can have a hotter signal output which can make the amplifier distort early (feel free to use it on Passive mode even with active basses if such additional distortion is desired).
- Microtubes: Engages the Microtubes Engine™ to add natural compression, organic harmonic enhancement, and saturation ranging from mild overdrive to high gain bass rage. The Microtubes Engine operates before the clean section (you can, therefore, use the 4 Band Active EQ for additional tone shaping in addition to the Tone knob described below).
- Drive: Sets the Microtubes Engine’s distortion level. Ranging from soft, warm overdrive to devastating saturation plus everything in between.
- Tone: Controls the high harmonic content of the Microtubes Engine via a variable low pass filter: crank it up for additional attack and definition or dim it down for a smoother sound. This is handy when running bright EQ settings or cabinets with tweeters.
- Level: Controls the Microtubes Engine’s output volume.
- Blend: Mixes between the Clean and Distortion signals (Microtubes Engine).
- B3K/VMT: Selects between two overdrive circuits: B3K mode will deliver an aggressive, percussive sound while the VMT will bring up the mids for a warmer, more neutral character.
- Gain: Changes the volume of the signal driving the Active 4 Band EQ. You can set it low for cleaner tone or set it higher for more aggressive growl.
- Bass: +-12dB at 80Hz. Changes the low content of the signal.
- Low Mids: +-12dB of the selected frequency via the LOW MIDS ƒ switch (described below).
- Low Mids ƒ: Use this switch to change the frequency of the low mid band between 250Hz and 500Hz.
- Hi Mids: +-12dB of the selected frequency via the HI MIDS ƒ switch (described below).
- Hi Mids ƒ: Use this switch to change the frequency of the hi mid band between 1.5kHz and 3kHZ.
- Treble: +-12dB at 5kHz. Changes the high content of the signal.
- Master: Controls the overall volume of the amplifier. This control does not affect DI output or effects loop level.
- Mute: Mutes the amplifier.
- Footswitch: The Footswitch jack allows you to remotely engage and disengage the Microtubes Engine via our Intelligent Footswitch (sold separately). Hold the footswitch to Mute the amplifier. The VMT/B3K push button will remain operational with the Intelligent Footswitch plugged in.
- Dimensions: 23.2x19x7.3 mm (9.13x7.48x2.87 in)
Back Panel Features
- Speaker Output: Connects the amplifier to your cabinet. This Speakon combo jack allows for either Speakon or ¼” speaker cable operation. The minimum load for the amplifier is 4Ω. For higher impedance loads the maximum output power is reduced. The Microtubes 500 amplifier can run without a cabinet connected to this output. WARNING: Do not use an instrument cable with this jack. Using an instrument cable can damage your amplifier. Do not use a load lower than 4Ω.
- Headphone Output: Headphones with 1⁄4” plug connector can be connected to this jack. For quiet operation remove any speaker cabinet connected to the amplifier, as connecting the headphones does not disable the speaker output.
- Send: Line level effects loop output. Connect a cable from this jack to the input of any pedals used in the effects loop. The output can be used to connect to another power amplifier or a sound card. The output is not controlled by the Master volume. Gain control can be used to change the signal le
- Return: Line level effects loop input. Connect the output from your effects loop pedals to this connector.
- Post-Pre: Selects which signal will be sent to the Balanced output. Selecting PRE, sends a clean copy of your input bass signal. Selecting POST delivers the processed signal by the preamplifier (Microtubes Engine, gain, eq.)
- Ground Lift: Lifts the ground of the Balanced output. If you are hearing mains frequency hum in your setup, try changing this setting.
- Balanced Output: Connects the Microtubes 500 preamplifier to balanced equipment (mic preamp, console, recorder, compressor, audio interface, etc.) via a standard XLR connector. The balanced signal level is not affected by the Master volume.
- Fan: The fan cools the amplifier and should run at all times. Be sure to never cover the vent holes on either side of the chassis.
- AC Socket: Connects the power cord to the amplifier.
- AC Power On/Off: Turns the amplifier on or off.