Dave Smith Instruments Intros DSM01 Curtis Filter For Eurorack Modular Synthesizers

dave-smith-instruments-dsm01-curtis-filter-eurorack-moduleDave Smith Instruments today introduced the DSM01 Curtis Filter – a version of his classic Sequential-style filter in a Eurorack module.

Dave Smith’s first-ever offering for modular synthesizer users is the DSM01 Curtis Filter – what they call ‘the very heart and soul of the Dave Smith sound’.

The DSM01 is a compact, 8 HP Eurorack-format module. The filter is a resonant low-pass design that can be switched between -12 dB and -24 dB operation and driven into self-oscillation in -24 dB mode. A Boost switch lets you overdrive the input stage for more aggressive coloration.

In addition to its Curtis filter, the DSM01 provides its own responsive, low-noise VCA with LED CV indicator. There are two separate outputs—one pre-amplifier and the other post-amplifier. This not only gives you added signal routing flexibility, but also frees your system’s existing VCAs for other tasks.


  • In/Out
    • 1 CV In – Frequency (3.5 mm jack) Range: 0 to 10V
    • 1 CV In – Resonance (3.5 mm jack) Range: 0 to 10V
    • 1 CV In – VCA (3.5 mm jack) Range: 0 to 10 V
    • 1 Audio In (3.5 mm jack) +/-5V or 10V p-p
    • 1 VCF Out – pre-VCA (3.5 mm jack)
    • 1 VCA Out – post-VCA (3.5 mm jack)
    • Self oscillation in -24 dB/octave mode, tracks at 1V/octave
  • Power
    • Internal power connector (ribbon cable included)
    • Current draw: +12V @ 36mA, -12V @ 25mA
  • Physical Specs
    • 1.59″ W x 5.06″ H (40.3 mm x 128.5 mm)
    • Depth (measured from back of panel with power cable installed): 1.06″ (27 mm)
    • Mounting screws included

Here’s an audio demo, via synthesist Robert Rich:


The Dave Smith Instruments DSM01 Curtis Filter module is expected to be available in August for US $179. See the DSI site for more info.

14 thoughts on “Dave Smith Instruments Intros DSM01 Curtis Filter For Eurorack Modular Synthesizers

    1. As I understand it, Dave had mr. Curtis do new chips for him alone (only Dave has these chips) before he died, and these surface mount versions are still in production… Dave uses them for everything (up until the new Pro 2 wich is the only exeption).

  1. Trying to use my ears to determine the signature of this filter, it almost doesn’t have one, am I right? Is this the filter that is in every 08 and other DSIs?

  2. 180 notes for a filter is a bit steep. For that price you could get a small Korg analog synthesizer and have money left over for cables and beer. For not much more you could get a Microbrute. The Curtis filter is not a bad one, but it’s not all that special either.

    1. It seems you don’t do modular. Pricewise, this component is about average. Sure you buy a cheap Korg for less, but it wouldn’t have the same functionality.

      1. A lot of modular gear is overpriced. Specialist modules from small boutique companies can reflect the difficulty or unfavorable economics of small-run development, but many basic components are priced far, far out of proportion to anything other than the GAS of modular buyers.

        1. I would say not really. Every module is a separate device that takes time to develop and make, small orders for things like printing circuits and small parts orders, short printing and faceplate jobs, I think they are a good price for what you get most of the time.

      2. There is not much functionality on offer here. I’m pretty sure that an oscillator (or 3), and LFO, a filter, and a VCA comprise greater functionality. Bear in mind you’re buying an IC here with a couple of knobs attached, as opposed to discrete circuitry – it’s just monopoly pricing.

        1. It’s not the knobs that people are paying for, it’s the CV ins. What makes modular interesting is the wiring. Sending a control voltage into the frequency from some other module is where things get interesting.

  3. If someone asked me what filter I dislike the most (moog, arp, wasp, ems…) this would be my pick without any doubt. What made it special some 30 ago, is that it was cheap and that made possible the poliphonic revolution. Only drawback is that it is cheap both in price and sound.

Leave a Reply