ALM/Busy Circuits PPEXP1 ()
Four HP of pure rhythmic expansion—this unassuming box turns Pamela’s PRO Workout into a clocking powerhouse.
Overview
If you've ever stared at your Pamela’s PRO Workout, wishing it could do just a little more—more clocks, more sync outputs, more flexibility—then the PPEXP1 isn’t just an upgrade, it’s a quiet revelation. Built by ALM/Busy Circuits, a name that carries serious weight among modular heads who care about timing precision and rock-solid sync, this tiny 4 HP expander doesn’t reinvent the wheel, but it sure adds a few extra ones. It’s not a standalone hero; it’s the supporting player that lets the star shine brighter. Designed specifically to bolt onto the Pamela’s PRO Workout (and only that), the PPEXP1 unlocks dedicated outputs for fixed clock, utility signals, DIN Sync, and MIDI clock—functions that, without it, would eat up valuable front-panel real estate or require messy workarounds.
ALM/Busy Circuits has built a reputation on doing digital right in the analog world—modules that handle clock division, synchronization, and timing with surgical accuracy. The PPEXP1 fits neatly into that philosophy: no frills, no flashy lights, just functional, reliable expansion. It’s the kind of module you don’t think about once it’s installed—because it just works. And for Eurorack users juggling multiple drum machines, sequencers, and vintage gear that demands DIN Sync or MIDI clock, having those signals readily available without rerouting or buffering is a small luxury that pays off every time you start a session.
Specifications
| Manufacturer | ALM/Busy Circuits |
| Dimensions | 4 HP, 32 mm deep |
| Current Draw | 40 mA +12V, 0 mA -12V, 0 mA 5V |
| Price | $159 |
Key Features
Dedicated Clock & Sync Outputs
The PPEXP1’s main job is to free up the Pamela’s PRO Workout’s front-panel outputs by providing additional, fixed connections on the back. That means the fixed clock, utility outputs, DIN Sync, and MIDI clock signals—normally patched from the front—are now available as dedicated outputs via the expander’s rear connector. This is especially useful in complex racks where the PRO Workout is permanently mounted and used as a central timing hub. Instead of using up precious front-panel jacks for permanent connections, you route them cleanly through the PPEXP1, leaving the front free for modulation, resets, or experimental patching. It’s a subtle but meaningful workflow improvement that reflects ALM’s deep understanding of how these modules are actually used.
Rear-Panel MIDI TRS Configuration
One of those small but brilliant touches: a switch on the rear of the module lets you select the MIDI TRS type. Since MIDI over TRS cables can follow different pinout standards (like the now-common 3.5mm tip-sleeve-ring versus ring-sleeve-tip), this switch eliminates guesswork and compatibility headaches. You set it once, match it to your receiving device, and forget about it. No more swapping cables or wondering why DIN Sync isn’t triggering your vintage drum machine. It’s a minor hardware detail that speaks volumes about the thought put into real-world usability.
Included MIDI DinTRS Adapter Cable
The module ships with a MIDI Din-to-TRS adapter cable, which might seem trivial—until you’ve spent 20 minutes hunting for one that actually works. This isn’t just a courtesy; it’s recognition that the whole point of DIN Sync and MIDI clock outputs is to connect to external gear, and ALM makes sure you can do it right out of the box. No extra purchases, no compatibility roulette. It’s the kind of inclusion that suggests the designers aren’t just making modules for a spec sheet—they’re building tools for people who gig, record, and patch every day.
Collectibility & Value
While production years and original MSRP details aren’t confirmed beyond the listed $159 price, current market listings on ModularGrid show the PPEXP1 trading between $133.42 and $158.53. Most units hover in the mid-$140s, with a few reaching close to the original price point. There’s no evidence of significant premium or scarcity—this isn’t a grail module—but the consistent pricing suggests steady demand among users who rely on Pamela’s PRO Workout in their racks. Given its niche role as an expander, it rarely appears on the market independently; most listings are likely from users upgrading or downsizing their systems. No data is available on common failures, maintenance issues, or long-term reliability, and given ALM’s build quality, it is a reliable expansion module.
eBay Listings
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