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• 8ms - Lowest Latency Open-source Sampler / Synth

  P. T. • 05/04/2017 at 19:23 • 0 comments

  Latency is a key characteristic of a sampler. The lower it is, the more comfortable it is to play an instrument. Even normal human speech appears to be out of sync on video when sound is delayed by 50ms or more. With digital instruments most players' preference is to achieve latency lower than 10ms.

  The latency itself appears due to processing delay, while a synth or a DAW is processing note input from a keyboard or controller, adds time for loading a sample, starting playback, applying digital filters, buffering, sending data to ADC and playing. Note that buffering is the only part of total latency visible in DAW or sound card settings on a computer.

  Naturally its been a great question for us to find out how much can be achieved with a sampler written on Python and running on a Raspberry Pi. The answer is to measure.

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• PCB Revision 2 Preview

  P. T. • 02/26/2017 at 10:36 • 2 comments

  Following testing of the initial prototype, new revision of the SamplerBox PCB is getting ready for manufacture. The dimensions were reviewed to reduce size of the board and also to locate audio connectors and controls on the back of the device.

  Large balanced TRS jacks have been replaced with minijack to make the SamplerBox more miniature. The circuitry is designed to allow connecting SamplerBox to either unbalanced or balanced inputs using a special balanced cable, which offers same level of noise protection as TRS jacks.

• Fully Working Sampler Board

  P. T. • 02/07/2017 at 15:49 • 1 comment

  A year ago I set off on a journey to create a custom board that would be designed to run SamplerBox - the best open-source sampler available.

  And the great news are, this is now done. I've designed and manufactured a board that connects to Raspberry Pi and provides necessary audio interfaces: MIDI IN/THRU, onboard DAC, balanced line outputs, headphone amp, display and control buttons.
  

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• PCB Assembly and Testing

  P. T. • 02/03/2017 at 05:23 • 0 comments

  The sampler board assembled and after adding a couple of minor mods DAC is fully functional, as well as program change buttons.

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• Prototype PCBs Ready

  P. T. • 04/20/2016 at 00:03 • 0 comments

  SamplerBox 1 PCBs have been manufactured and it is now ready for assembly and testing. This prototype board is designed to host a Raspberry Pi board, providing MIDI interface, I2S DAC, line outputs and a headphone amplifier. Two GPIO buttons and 16x2 LCD display are placed on the opposite side of the board.

• Prototype PCB testing is complete

  P. T. • 02/23/2016 at 13:48 • 5 comments

  Prototype PCB testing is complete at this point and it is being prepared for manufacturing.

  The current design is a 11x11cm PCB that holds all required peripherals and plugs into Raspberry PI GPIO socket, eliminating the need for any wiring as DAC, all peripherals and connections are placed onto one board. It is designed to fit stylish aluminium off-the-shelf 12x12x4 cm enclosure.

  A concept drawing.

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