$114.27
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components.
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Mounts & Accessories recommended
Recorders, NVRs & Storage recommended
Licenses & Software where applicable
Services & Training optional
At A Glance
- Input Impedance
- 1 MΩ
- Output Impedance
- 470 Ω
- Max Output Level
- +7 dBV
- Noise Floor
- -87 dBV
- Tone Controls
- BASS: ±14 dB, 33 Hz / TREBLE: ±11 dB, 8.4 kHz
- Gain Control
- +0.5 dB to +26 dB
- Frequency Response
- 20 Hz to 20 kHz, ±0.75 dB
- Bypass
- True Hardwire
- Current Draw
- 6.5 mA
- Power Supply
- 9 Volts DC
Description
MXR positioned the Micro Amp Plus (M233) as an upgraded iteration of its classic Micro Amp boost circuit, adding active EQ controls, low-noise op-amps, and true hardwire bypass to the core clean-boost platform.
The pedal delivered a gain range of +0.5 dB to +26 dB across a frequency response of 20 Hz to 20 kHz (±0.75 dB), with a noise floor of -87 dBV and a maximum output level of +7 dBV. Two tone controls shaped the boosted signal: a bass band centred at 33 Hz with ±14 dB of cut or boost, and a treble band centred at 8.4 kHz with ±11 dB of cut or boost. Input impedance was 1 MΩ and output impedance 470 Ω. The unit drew 6.5 mA from a 9 V DC supply and engaged via true hardwire bypass.
Owners sourcing a compatible power supply should confirm the 9 V DC centre-negative standard common to most compact effects units; a qualified guitar technician or electronics repair specialist can assist with any internal servicing or bypass switch maintenance.
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Put yours on the record.
The catalog shot showed one finish, under one light, a long time ago. Yours has been played. Photos from owners are what the next person finds when they are trying to identify a part, match a finish, or work out whether the one they just bought is really what the seller said it was.
Comments
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Specs only go so far. What actually fits, what breaks first, what the factory got right and what everyone ends up changing — that lives with the people who own them, not in a datasheet. Post what you know and it stays on this page for whoever comes looking next.
Ask Blake About This Rig
Shop Lead · 30 years of shred · Replies within 1 business dayBuild Your Complete System
Manufacturer-verified compatible cameras, recorders, mounts, accessories, and licenses for this product. Adjust quantities and add the entire bundle to your cart in one click.
Item
Qty
Status
Price
Mounts & Accessories recommended
Recorders, NVRs & Storage recommended
Licenses & Software where applicable
Services & Training optional
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Since 2007
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