2hp Switch (2013–)

Name: 2hp Switch
Brand: 2hp

A deceptively simple gatekeeper that turns signal routing into a performance instrument—when it clicks, your patch breathes.

Overview

You don’t notice the 2hp Switch at first. It hides in plain sight, a sliver of brushed aluminum tucked between oscillators and filters, doing its job so quietly you might forget it’s there—until the moment it isn’t. Then the patch collapses. No warning, no drama—just silence where there used to be motion. That’s the thing about routing: it’s the skeleton of your modular system, and when it falters, everything sags. The Switch doesn’t just route signals—it shapes how they move, when they appear, and in what order. With four inputs and one output, it’s a traffic director for audio, CV, or gates, letting you jump between sources manually or via control voltage. It’s not a mixer. It doesn’t blend. It selects. And that selection—crisp, decisive, almost surgical—can make the difference between a static patch and one that feels alive.

Despite its tiny 2hp footprint, the Switch punches above its weight in utility. It’s the kind of module you reach for when you want to swap between two LFO waveforms on a filter, alternate between drum voices, or toggle modulation sources in real time. The front panel is stripped to the bone: four input jacks, one output, a small knob for manual selection, and a CV input with attenuator. No extras. No frills. But that simplicity belies a subtle complexity in behavior. The Switch uses analog switching circuitry, which means it passes signals without digitizing or buffering—what goes in comes out, more or less, just routed differently. It handles audio just fine, though purists note a slight coloration, especially with high-impedance sources. More critically, when used with V/Oct pitch signals, the manual warns of “slight variations” that can cause tuning discrepancies. It’s not a dealbreaker, but it’s enough to make you think twice before routing your main oscillator’s pitch CV through it without testing.

Where the Switch really sings is in rhythmic modulation. Pair it with a sequencer or LFO, and you can create evolving textures by cycling through different filter cutoffs, envelope shapes, or even entirely separate sound generators. Because it responds to CV, you can modulate the selection parameter like any other—automating transitions, creating pseudo-random sequences, or even using it as a crude sample-and-hold by feeding in stepped voltages. The manual selection knob is satisfyingly precise, with clear detents for each of the four channels, making live performance tweaks intuitive. It’s not bidirectional—unlike some larger sequential switches, you can’t reverse the order or use it as a round-robin router without external logic—but that’s part of its charm. It’s a forward-moving selector, not a loop. You choose, it obeys.

Specifications

Manufacturer	2hp
Production Years	2013–
Original Price	$119
Width	2hp
Depth	45 mm
Power Consumption +12V	31 mA
Power Consumption -12V	16 mA
Power Consumption 5V	0 mA
Inputs	4 x 3.5mm (audio/CV/gate)
Output	1 x 3.5mm (audio/CV/gate)
CV Input	1 x 3.5mm with attenuator
Manual Selection	Rotary knob with 4-position detent
Signal Type	Analog switching (unidirectional)
Switching Speed	Extremely fast (electronic switching)
Color Options	Silver, Black

Key Features

Minimalist Design, Maximum Flexibility

The 2hp Switch is the definition of efficient design. At just 2hp wide, it’s one of the narrowest signal routers in Eurorack, making it a favorite for skiff builders and those running tight on space. The aluminum panel is sturdy, with cleanly labeled jacks and a smooth-turning selection knob that gives tactile feedback at each of the four positions. There’s no LED indication of the active channel—some users see this as a flaw, but others appreciate the minimalism. You learn to feel the detents, to trust the knob. The lack of visual feedback forces you to internalize the routing, which, in a strange way, makes the module feel more integrated into your performance. You’re not watching a light—you’re turning a switch, like flipping a breaker or engaging a gear. It’s mechanical in feel, even though the switching itself is solid-state.

CV Control with Attenuation

The CV input isn’t an afterthought—it’s central to the module’s identity. Feed it a 0–5V control voltage, and the Switch will step through its four channels proportionally. But because Eurorack CV sources vary wildly in voltage range and offset, the built-in attenuator is essential. An LFO running from -5V to +5V won’t step evenly through the channels without being offset and scaled. The attenuator lets you dial in the exact range needed, so a triangle wave can sweep cleanly from input one to four without skipping or stalling. Users report that getting smooth, linear stepping takes some patching finesse—sometimes requiring an offset module or attenuverter—but once set, it’s rock solid. The CV response is linear, meaning voltage maps directly to channel position, which makes it predictable and easy to sync with sequencers or clock dividers.

Signal Integrity and Limitations

While the Switch handles audio signals without audible degradation in most contexts, it’s not transparent in the way a buffered mult or active mixer might be. Some users report a slight thinning of high frequencies when routing certain waveforms, particularly with long cable runs or high-impedance outputs. This isn’t a flaw per se—it’s a characteristic of the analog switching topology, which relies on FETs rather than op-amps. The lack of buffering means the Switch doesn’t isolate inputs from outputs, so impedance interactions can occur. For critical audio paths—say, routing a delicate pad through multiple effects—the Switch might not be the cleanest choice. But for modulation, gates, or percussive elements, its character is more than acceptable. Where it stumbles is with precision pitch control: the manufacturer’s note about “slight variations” in V/Oct signals is real. If you’re switching between two pitch sources for a melody, you might notice tuning drift or inconsistency. It’s not broken—it’s just not designed to be a precision pitch router.

Historical Context

The 2hp Switch arrived in 2013, a time when Eurorack was shedding its niche status and entering a period of explosive growth. Manufacturers were racing to fill every conceivable function in the format, and space efficiency became a premium. 2hp, founded by Tony Rolando (also known for the Organelle and later, the Lush-101), built its reputation on ultra-compact, elegantly designed modules that did one thing well. The Switch fit perfectly into that ethos. It wasn’t the first voltage-controlled router—Doepfer’s A-151 had been around for years—but it was among the first to offer such functionality in a 2hp form factor. At a time when many modules were 8hp or wider, the Switch felt like a revelation. It wasn’t trying to replace larger sequential switches; it was offering a leaner, more focused alternative for those who valued space and simplicity over bidirectional routing or manual sequencing.

Its main competitors were modules like the Doepfer A-151, which offered bidirectional switching and multiple modes, and the Erica Pico Seq, a 3hp module with clock input and forward/reverse logic. The 2hp Switch didn’t compete on features—it competed on footprint and immediacy. It was less a sequencer and more a selector, built for quick swaps rather than complex automation. In an ecosystem increasingly crowded with feature-rich modules, the Switch stood out by doing less, but doing it exceptionally well. It also reflected a broader trend in modular design: the move toward “utility” modules that, while not flashy, were indispensable in daily use. The Switch wasn’t a sound generator, but it shaped how sounds moved through a system—making it quietly essential.

Collectibility & Value

The 2hp Switch has never been rare—2hp maintained steady production, and the module remains available new from dealers. As a result, it’s not a collector’s item in the traditional sense. You won’t find vintage premiums or scalper markups. But that doesn’t mean it’s without value. On the used market, Switch modules typically sell for $75–$95, depending on condition and color (black is slightly more sought after than silver). Because it has no moving parts beyond the selector knob, failure rates are low. The most common issue reported is intermittent contact in the knob, usually due to dust or wear, which can be resolved with contact cleaner. There are no known firmware updates or revisions—the module has remained unchanged since its introduction.

Buying used? Check that all four positions engage cleanly and that the CV response is linear across the range. Patch in a slow LFO and verify that it steps through each input without skipping or sticking. Also test with a pitch CV to see if tuning remains stable—some users have reported drift, though it’s often patch-dependent. The module draws modest power (31mA on +12V, 16mA on -12V), so it’s safe for even the most tightly loaded power supplies. No special maintenance is required, and there are no capacitors or other components known to degrade over time. If you’re building a compact or travel-friendly system, the Switch is still one of the best routing solutions under 3hp. It’s not the most feature-rich, but it’s reliable, immediate, and built to last.