The Crumar Bit 01, released in early 1985, was not simply a repackaged Bit One keyboard in module form, but rather a significantly "souped-up" expander version that addressed many of the original Bit One's limitations. Designed by Mario Maggi (creator of the legendary Elka Synthex), this deep 3U rackmount module represented Crumar's response to user feedback and demonstrated the company's commitment to refining their hybrid digital/analog architecture.

Available in both black and ivory finishes, the Bit 01 retained the fundamental sonic character of the Bit One - combining twelve digitally controlled oscillators (two per voice) with analog 24dB/octave low-pass resonant filters to produce warm, powerful sounds capable of competing with far more expensive instruments. At £499, it offered exceptional value for money and should have been high on every analogue enthusiast's shopping list.

Enhanced Architecture and New Parameters

The Bit 01 maintained the Bit One's six-voice polyphonic architecture with dual DCOs per voice, each offering triangle, sawtooth, and variable pulse width square waveforms across a pitch range of 32', 16', 8', and 4'. The analog filter section featured full ADSR envelope control, cutoff, resonance, envelope depth, keyboard tracking, and polarity inversion. Like its predecessor, the Bit 01 employed two LFO systems per voice (offering sine, square, and sawtooth waveforms) and two ADSR envelope generators per voice - specifications that remained superior to most competing affordable synthesizers.

However, the Bit 01 introduced several crucial improvements that transformed it from a promising instrument into a genuinely professional tool. Most significantly, Crumar added programmable parameters that had been frustratingly manual on the Bit One. The noise generator, previously accessible only via a front-panel slider, was now programmable on DCO1, allowing noise-based patches to be stored and recalled properly. The detune parameter on DCO2, which had required manual slider adjustment on the Bit One, was now fully programmable and stored within each patch. This addressed one of the most serious workflow issues of the original design, as detuning between oscillators is crucial to creating warm, chorused ensemble sounds.

Additionally, the Bit 01 introduced a parameter to control the maximum modulation depth applied by the modulation wheel, and programmable patch volume, giving users more comprehensive control over their sounds. A new modulation wheel depth parameter allowed fine control over performance expression.

Trade-offs and Limitations

While the Bit 01 gained significant new capabilities, it also sacrificed some features from the Bit One. Most notably, the ability to sweep the DCOs' frequencies using the VCA's envelope generator was removed, limiting certain modulation routing possibilities. The distinctive Unison mode, which had allowed all oscillators to be stacked for massive monophonic lead sounds, also disappeared from the 01's feature set. These omissions were puzzling given the overall improvements elsewhere in the design.

The most significant limitation was the absence of a MIDI Out socket. Despite the dramatically improved MIDI implementation for receiving data, the Bit 01 could not transmit MIDI information, making it impossible to save sounds over MIDI. Users were still relegated to cassette tape storage for patch libraries - an increasingly archaic approach even in 1985.

Memory and Performance Features

One of the Bit 01's most significant advances was its expanded and reorganized memory system. While the Bit One offered 63 single patches with no ability to store split or double configurations, the Bit 01 provided 99 memory locations organized in an unusual but practical manner: 75 locations were dedicated to Bit One-style single patches, while 24 locations stored complete performances including splits and doubles. This meant that complex keyboard configurations could finally be recalled instantly rather than requiring manual setup for each performance.

The ability to store splits and doubles as performances was transformative for live work and studio production. Users could now save their carefully crafted layered sounds and split configurations, with each performance retaining independent settings for upper and lower zones, split points, and relative volume balances.

Bi-timbral Capabilities

Like the Bit One, the Bit 01 was bi-timbral, allowing any of its patches to be placed in Upper and Lower zones above and below a user-defined split point. The Split mode provided three voices per zone, while Double mode allowed two patches to be superimposed across the entire keyboard, reducing polyphony from six notes to three but creating rich, complex layered textures that more than compensated for the voice reduction. The depth and complexity of combined sounds in Double mode could produce results rivaling much more expensive instruments.

MIDI Implementation

The Bit 01's MIDI specification represented a dramatic improvement over the Bit One's severely limited implementation. Users could now exit Omni mode and the module recognized all 16 MIDI channels, making it properly integrable into multi-keyboard MIDI setups. The 01 also received MIDI controllers such as modulation and pitch-bend data, making it far more suitable for live performance where expression and real-time control were essential.

The module featured MIDI In and Thru sockets (though no MIDI Out), and could receive note numbers, velocity, patch changes, and performance controller data. While still not perfect, this represented a quantum leap from the Bit One's embarrassingly basic MIDI implementation that transmitted only note number and velocity on channel 1, and received in Omni mode only with patch changes.

Sonic Character and Applications

The Bit 01 inherited the Bit One's remarkable sonic capabilities, with lead synth patches and synth pads that could hold their own against Sequential Prophets and Oberheims costing significantly more. The module excelled at punchy brass sounds and warm polysynth patches, while also proving surprisingly adept at FM-style timbres including DX-series electric pianos and harp sounds - a versatility that belied its analog architecture.

The hybrid digital/analog design produced sounds that were crisp and clean while retaining analog warmth and character. Strange summing differences between DCO1 and DCO2 could create unexpected tonal variations when playing keys - an organic, CS80-like quality that some users appreciated for its musicality while others found unpredictable. These variations didn't cycle consistently through the six voices, adding an element of sonic surprise that could be either charming or frustrating depending on the application.

Minor sonic artifacts included occasionally audible LFO stepping, though these deficiencies were minor compared to the overall warmth and versatility of the instrument. When processed through contemporary digital effects like chorus and reverb, the Bit 01 could produce stunning results that justified its place in any serious synthesizer setup.

Market Position and Legacy

At a low launch price, the Bit 01 represented exceptional value, offering capabilities that should have made it a standard fixture in studios and on stages. Its professional 3U rackmount format made it ideal for integration into expanding MIDI-based setups, and its improved MIDI specification finally made it a proper team player in the emerging world of MIDI orchestration.

However, the Bit 01 appeared at precisely the wrong moment in synthesizer history. The mid-1980s marked the absolute zenith of FM synthesis worship, with digital technology dominating every aspect of music production from instruments to effects to recording formats. The analogue synthesis that the Bit 01 represented so capably was temporarily out of fashion, and even a well-designed, affordably-priced analog module struggled to gain traction in a marketplace obsessed with all things digital.

Technical Specifications

Format: 3U Rackmount Expander Module (Deep chassis) Finishes: Black, Ivory

Polyphony: 6 voices

Oscillators:

• 2 DCOs per voice (12 total)
• Waveforms: Triangle, Sawtooth, Variable Pulse Width Square
• Pitch Range: 32', 16', 8', 4'
• Modulation Sources: ADSR, LFO, Velocity
• NEW: Programmable detune on DCO2
• NEW: Programmable noise on DCO1

Low-Frequency Oscillators:

• 2 LFOs per voice
• Waveforms: Sine (Triangle), Square, Sawtooth (Ramp)
• Modulation Destinations: DCO1, DCO2, VCF, VCA
• Controls: Depth, Rate, Delay
• LFO Rate: Velocity-controllable
• NEW: Programmable modulation wheel depth

Filter:

• Type: Resonant low-pass filter
• Slope: 24dB/octave
• 1 VCF per voice
• Envelope: ADSR
• Controls: Cutoff, Resonance, Envelope Depth, Keyboard Tracking, Polarity Inverter
• Velocity-Sensitive Parameters: Attack Time, Envelope Depth

Amplifier:

• 1 VCA per voice
• Envelope: ADSR
• Parameter Range: 0-63
• Velocity-Sensitive Parameters: Attack Time, Amount

Memory:

• 99 total memory locations
• 75 single patches
• 24 performance memories (splits/doubles)
• Split and Double modes now storable
• REMOVED: Unison mode
• REMOVED: DCO frequency sweep via VCA envelope

Performance Modes:

• Polyphonic: 6-voice polyphony
• Split: Dual sounds with user-defined split point (3 voices per section) - now storable
• Double: Two sounds layered (3-note polyphony) - now storable

Audio Outputs:

• Stereo outputs (Left/Right)
• Random voice distribution in normal mode
• Upper/Lower distribution in Split mode

MIDI:

• MIDI In
• MIDI Thru
• NO MIDI Out
• All 16 MIDI channels recognized (Omni mode can be disabled)
• Receives: Note numbers, Velocity, Patch changes, Modulation, Pitch-bend
• Cannot transmit patch data
• Cassette tape storage only