adhoc Flow/1
Compact Form.
Expansive Sound.
Flow/1 is a compact 3D-printed loudspeaker based on a folded coaxial tapered quarter-wave tube. It is a DIY project for makers who want to build a bespoke loudspeaker, not just another small box. Flow/1 folds a 4.8L air mass through unequal-length segments of concentric rings inside a compact enclosure. Its patented acoustic geometry works with the driver layout and active FIR crossover to produce useful bass extension without booming, precise imaging, and balanced sound from a loudspeaker small enough to fit easily in a real room.
Designed Around The Air Flow
Compact, Tuned Enclosure
The enclosure does the work. Printed internal geometry controls the rear wave, spreads resonances, and lets a small loudspeaker reach lower without turning bass into boom.
Coaxial Point Source
Flow/1 packs a 180-degree swivel tweeter and an optimized quarter-wave path into a compact 5-liter enclosure. While small speakers usually dictate where you sit and what you hear, Flow/1 balances bass extension and placement versatility by ensuring every cubic centimeter performs a dedicated acoustic function.
Swappable Driver Modules
Flow/1 is designed around removable high/low driver modules. A complete driver pair can be swapped between enclosures in under a minute, making driver comparison, measurement, repair, and future upgrades practical. Current modules support SB Audience, AuraSound, Wavecor, Tang Band, and Dayton Audio drivers, with more to come.
Designed for the Print-Build-Do-It-Yourself Maker
Flow/1 is a natural project for the PBDIY community: makers who print, build, repair, and create things themselves, supported by shared knowledge rather than finished commercial products. It is an engineered loudspeaker system you build, configure, measure, and bring to life by hand.
- It is for makers who want a bespoke loudspeaker, not another off-the-shelf box.
- It is for listeners who want audiophile performance, satisfying bass, and stable imaging from a compact, versatile package that fits in a real room.
- It is for anyone who cares how and why a system works, not just whether it plays.
What You Get
Maker's Guide
A detailed build path covering materials, tolerances, assembly, and construction choices. The value is not just instruction; it is confidence that a physical object is being realized the way the design intended. Available To Everyone.
Click the image of the Maker's Guide to view or download the free Flow /1 Maker’s Guide and see what it takes to build a pair of compact, high-performance audiophile loudspeakers from 3D-printed parts, selected drivers, DSP, and careful assembly.
Design Files
Complete STL and STEP files for all enclosure components, optimized for printability, fit, and acoustic performance. Available to subscribers.
Click the image of the models to access the design resources, or to subscribe for access if you are not already a member.
Created from First Principles
Flow/1 started with the acoustic problem: move a 4.8L air mass through a 1.7-meter path, suppress tube modes, preserve imaging, and keep the loudspeaker small enough for a real room. The folded coaxial quarter-wave geometry described in U.S. Patent 7,925,036 B2 is the core. Driver layout, FIR crossover, modular construction, 3D printing, and a swivel high-frequency driver all serve that geometry.
Every dimension, every taper and fold, every cleft, dimple and pimple; every internal cubic millimeter has a purpose.
Flow/1 Explosion
Why Bother Building This Flow/1 Speaker?
Because Flow/1 is not just a box that makes sound. It is a compact loudspeaker system with the flow of air shaped and controlled down to the cubic millimeter, built to vanish as a source and leave behind only the music: full-spectrum, balanced, satisfying, and free of the exaggerations that make many small speakers impressive at first but tiring over time.
Most speakers in this size class force a tradeoff between depth and detail. By engineering every cubic centimeter into function, Flow/1 resolves these compromises. Its 5L enclosure and 180-degree swivel tweeter balance low-end authority with the placement versatility required for real listening spaces.
Flow/1 exists to challenge those tradeoffs through careful geometry, controlled loading, time alignment, and DSP, not brute size. The goal is simple: deeper bass from a smaller footprint, sharper image focus, and a more coherent presentation from a speaker that still suits a real room.
Because building it gives you access to the whole system:
- the acoustic design
- the physical design
- the DSP
- the reasoning behind the choices
This is not generic DIY for its own sake. It is a compact active loudspeaker designed for serious listening, with controlled low-frequency extension, point-source coherence, precise imaging, and a form factor that makes sense in everyday spaces. Because if you are the kind of person drawn to PIY, DIY, or BIY, the effort is part of the reward. You do not just end up with a product. You end up understanding the machine and hearing the difference those decisions make.
And because the cost of building one is not just money and time. It is an exchange. You put in care, attention, and effort, and in return, you get something personal, unusual, and deeply considered. Something that reflects your standards, not a manufacturer’s brief.
So the real answer is this:
- You bother if you want presence instead of mere playback.
- You bother if you want to build something rare.
- You bother if you want to hear what careful geometry, controlled loading, and coherent radiation can do in a compact system.
If that matters to you, then Flow/1 is exactly the kind of project worth building.
Press 'Subscribe For Access' to the Flow/1 3D files, future design updates, and the member forum.