Doepfer A138i

$86.94 to $127.00 Price Tier: Budget

All time low price

0 wishlisted

3 saved

Page last updated Jun 06, 2026

Pricing and availability

We compare 600+ stores and found this item at 3 stores. Prices updated June 5, 2026.

Store

Reviews

Price

$127.00

View Deal

5.0 (1)

$86.94 3 available New

$81.00 1 available Used

View Deal

4.6 (8)

$93.00 $92.00 $1.00 · All time low

View Deal

Average Price: $97

Budget/Beginner

$149

$350+

Price Tier

In the Modular Synthesizers category, Doepfer A138i is priced in the Budget/Beginner range. This is great gear to get started with or for creators on a budget.

Budget

Standard

High-end

Price History

Based on price data from 2 merchants for "Doepfer A138i". Prices shown reflect NEW condition. Tracking began Apr 2, 2026.

^* Product prices and availability are updated by Equipboard every 24hrs and are subject to change. Equipboard may receive compensation for purchases made at participating retailers linked on this site. This compensation does not affect what products or prices are displayed, or the order of prices listed. For more information, please refer to our affiliate disclosure.

Description

Edit description

The Doepfer A-138i is a compact 4-channel mixer designed to seamlessly integrate into your Eurorack setup, offering a versatile solution for both audio and control voltage (CV) signals. Whether you're a seasoned synthesist or just venturing into the world of modular synthesis, this mixer is engineered to provide flexibility and precision in your sound design process. Each of the four input channels is equipped with a volume control and a mute switch, allowing for dynamic manipulation of your signals. The module features an innovative output configuration: two mix outputs and two single output groups. This setup makes it possible to craft complex signal paths and explore new sonic territories.

The A-138i stands out with its DC-coupled connections, making it an invaluable tool for mixing audio and intricate CV signals. Thanks to its space-efficient design at just 6HP, this module is perfect for those with limited rack space who don't want to compromise on functionality. Power requirements are minimal, ensuring it integrates effortlessly into your existing setup. Whether you're balancing multiple audio sources or routing envelopes and LFOs for modulation, the Doepfer A-138i offers the adaptability you need to push your creative boundaries.

Key Features:

Compact 4-channel mixer for audio and CV signals
Volume control and mute switch per channel
2 mix outputs and 2 single output groups
DC-coupled connections for versatile signal mixing
Space-efficient at 6HP width
Power requirements: +10 mA (+12 V) / -10 mA (-12 V)

Product specs

Type	Mixer Eurorack Module
Depth	1.57" (40mm)
HP Size	6HP
Power Usage	±12V/10mA
Power Supply	Requires Eurorack case and power supply

FAQs

What is the primary function of the Doepfer A-138i Interrupting Mixer?: The Doepfer A-138i is a Eurorack mixer module designed to allow for the mixing of audio or control voltage (CV) signals. It features an interrupting function, which can mute or bypass each channel individually, making it versatile for live performance or complex patching setups.
How many channels does the Doepfer A-138i mixer offer?: The Doepfer A-138i provides four channels, allowing you to mix four different audio or CV signals within your Eurorack setup.
Does the Doepfer A-138i require a specific power supply?: Yes, the Doepfer A-138i requires a Eurorack case with a compatible power supply, using ±12V and drawing 10mA.
What are the dimensions of the Doepfer A-138i in HP size?: The Doepfer A-138i has a width of 6HP, making it a compact option for Eurorack systems.
Can the Doepfer A-138i be used for both audio and CV signals?: Yes, the Doepfer A-138i is designed to handle both audio and control voltage signals, providing flexibility in modular synthesizer setups.

Videos

Add video

DominikVogel

Doepfer A-138i Interrupting Mixer (Review)

DominikVogel

Reviews

Add review

PROS

Features mute switches for easy sound control
Extra outputs enhance connectivity for effects and external gear
Fine sound quality with no noise
Compact design (6 hp) saves space in setups
Improved design with better knob and jack placement
Suitable for complex mixing tasks, especially with oscillators
High-quality build and reliability from Doepfer

CONS

Grounding required for switches to prevent popping
Knobs are closely spaced, limiting finger room
Small module design leads to smaller, more fiddly knobs

Owner Insights

We analyzed real musician discussions from forums and Reddit to find what players love, question, and tweak about Doepfer A138i.

Setup and maintenance

0 0

Older units may require chip replacement if used; ensure proper power delivery and check for signs of damage or miswiring.
Source
0 0

Replacing electrolytic capacitors may be necessary if power issues persist, affecting audio clarity.
Source

User experience

0 0

Some owners report noise issues when using the Doepfer A-138i with certain power supplies like the uZeus, especially noticeable with LFOs.
Source
0 0

Some users find that moving away from compact or menu-heavy modules like the Disting EX to more tangible modules like the A-138i enriches the modular experience.
Source

Features and functionality

0 0

The top mix control can become scratchy, affecting sound quality when set past noon or at minimum.
Source
0 0

The Doepfer A-135-2 Mini Quad VCA / VC Mixer offers both audio and CV mixing, making it versatile for small systems.
Source

Use cases and applications

0 0

The A-184-1 Ring Modulator/S&H/T&H/Slew Limiter is noted for its useful track & hold and sample & hold functions, though some find the pitch from S&H unstable.
Source
0 0

Owners prefer the A-138i for hands-on, WYSIWYG setups that enhance performative modulation, providing a more intuitive experience than menu-driven modules.
Source

Comparisons

0 0

The A-111-6 Miniature Synthesizer Voice is praised for its powerful performance in small systems compared to MI Plaits, with a preference for its subtractive synthesis interface.
Source
0 0

The A-138i's larger format and stiffer knobs are seen as superior in ergonomics compared to compact Doepfer mixer modules, aiding in better interfacing.
Source

Build quality

0 0

The A-140-1 Envelope Generator is larger than average EGs at 10HP, but its sound quality justifies the space it occupies in a setup.
Source
0 0

The Doepfer A-138i is favored for its ergonomics, with larger, more precise knobs that enhance tactile interaction and control, compared to compact alternatives.
Source

Mods and upgrades

0 0

The A-111-6 has been recommended for those looking for a compact, powerful synth voice, offering a sound reminiscent of the SH-101.
Source

Value and pricing

0 0

It's noted that Doepfer modules, including the A-135-2 VCA, are well-priced, especially when purchased from Thomann, even with international shipping costs.
Source