Tiptop Audio HATS909 Hi-Hats Drum Module

Tiptop Audio HATS909 is the Roland TR-909's original closed and open hi-hats circuits adapted for use in eurorack modular synthesizer format and tested to sound like a machine coming fresh off the assembly line back in the 80s. Improving on the original, Tiptop Audio added some great new features that expand the sound palette of hats that can be produced with this small, powerful module.

The original TR-909 circuit is made with a combination of low-fi 6-bit sound samples that pass through a series of analog elements to provide envelope and filtering to the source sound. HATS909 allows for manual and voltage control of the sample's tuning, which provides anything from crushed hats and short ticks to the original sound and anything in between. A modulation switch allows you to tap a voltage control to either the tune input or the internal VCA for modulation with external control signals or for adding AM or FM synthesis in the audio range from external oscillators, other drum sounds or just about any sound source. HATS909 also offers a switch for a direct tap to the output of the original sample, bypassing all other internal analog processing, giving you the pure source sound for synthesis any way you want with your own modules.

Just like the other drums in this series, HATS909's high-powered output gain stage allows you to further harmonize the sound through distortion and clipping. On each gate input, Tiptop Audio designed a dual pulse-shaper circuit so you can trigger HATS909 with trigger/gate signals from step sequencers, clock dividers or any other pulse/clock sources.

• Module controls
• TUNE knob: VCO tuning control
• LEVEL knob: master output gain level
• CH DECAY and OH DECAY knobs: amp envelope decay stage times
• SOURCE switch: set to RAW to bypass envelope and filtering of samples
• MODULATION switch: routes FM/AM CV input to either VCO tuning (FM) or VCA level (AM)
• CV IN knob: attenuates FM/AM CV input level
• ACCENT knob: accent level control, affects loudness and attack levels
• Patch points
• FM/AM input: CV input for VCO tuning or VCA level modulation
• ACCENT IN input: gate trigger input to trigger accent
• OH GATE and CH GATE inputs: gate trigger inputs to trigger open hi-hat and closed hi-hat sounds
• VC-TUNE input: CV control over VCO tuning
• HATS OUT output: audio output
• Physical specifications
• Size: 8hp
• Module depth: 36mm
• Power usage: 33mA @ +12V, 22mA @ -12V