After reviewing three of the most powerful synthesizers on the planet within the last six weeks, I thought I would let my hair down and take a look at an effect plugin for a change. Of course, Sigmund from D16 Group doesn’t exactly make it easy for me to kick back and relax, but you certainly won’t hear me complaining.

In fact, this might just be the single most powerful delay plugin I’ve ever encountered. I’m bloody serious. In terms of flexibility, Sigmund is nothing short of insane!

The Review

Let’s just get this out of the way, shall we? Sigmund’s interface is absolutely gorgeous! Embracing the traditional rack mount look, its beautifully backlit tangerine-hued VU meters are mouth-watering eye candy. The knobs are three-dimensional. The preset browser is sleek and easy to navigate. Also, there’s a nag screen that pops up when you try to click away from a preset that you’ve messed with, asking if you want to keep or discard changes to its settings, which is a really helpful feature. I don’t know how many times I’ve lost presets I’d toiled on for hours with a single mouse click.

Another thing I’d like to call attention to is that two years ago, when Sigmund was first released, its CPU hit was potentially fatal, but today at version 1.1.2 this is no longer a soul-crushing issue. That being said, you still have to make some room for Sigmund to breath, as it requires a little “oomph” when firing on all cylinders, but it’s certainly not going to crash your DAW. Thing is, I’m a sound designer, so processing power isn’t that big of a deal for me since I usually sample everything to audio anyway, but for anyone working with large projects with a bazillion things going on, Sigmund might slow you down a bit – but don’t let that discourage you from using it in your mixes! You just need to remember that with great power comes… well, you’ve seen the movie.

There are four delay lines, but really, there are eight if you toggle off the “Join Channels” button within the Delay Parameters section to use both the left and right delay lines separately, or in the case of Mid+Side mode, you can do the same for both the center and side channels, but I’ll get to that later. Also, there’s a hidden Predelay subsection with identical controls that basically just delay the delay, so technically there are actually sixteen delay lines, eight of which are audible.

Okay, now for those “Channel Mode” buttons in the top left corner of the Delay Parameters section below the numbered labels. “L/R” mode, as I explained earlier, assigns a delay for both the left and right stereo channels when they aren’t joined, whereas “M+S” mode assigns a delay for the “mid” channel, which is basically just a mono signal, and a second delay for the “side” channels, being the far left and right stereo signals that produce a wide panorama. This is a great way to program very natural sounding echoes, with a narrow monophonic sound followed by a rich, wide stereo sound.

Of course, all of this depends on whether or not the input signal is stereo or mono. Let’s say you have a stereo input, but you want to mix it down to a mono signal and use L/R mode to create a sort of ping-pong delay where each echo is a mono sound panned hard left and right. The “To Mono” button will do just that. Of course, if you join the channels, it will just be a mono delay. You can also flip the stereo image with the “Channel Swap” button that does exactly what its label indicates.

Moving right along to the Delay Parameters section, we have two separate panels for a MultiMode Filter and Time controls for Predelay and Feedback Delay. This is where I think the wording has become a little confusing, but not so much within the plugin as in the manual, which refers to the filter as a “multimode resonant filter and distortion module”. This had me looking around for drive parameters in the Filter panel, which aren’t there, but what is meant by this is that the Multimode Filter has a direct relationship with the Overdrive module in the bottom-left corner of the GUI. The buttons in the top-left corner of the Filter panel labeled “Pre” and “Post” determine the serial routing configuration for the filter and overdrive modules. In other words, in “Pre” mode, the filter is situated before the Overdrive module, and in “Post” mode, the filter is situated after the Overdrive module. At first, I thought these buttons indicated the filter’s overall position within the feedback loop, but that’s actually controlled by the “Feedback” button, filtering only the processed signal being fed back into the delay stage.

There are three basic filter types: Lowpass, Bandpass and Highpass, and a global “Cutoff” and “Reso” knob for all of the above. I think the use of the term “multimode” is a bit of an overstatement, being that typical, common garden variety multimode filters usually offer at least half a dozen filter types, although technically there are three multiple modes, so it’s not entirely out of context. However, the filters themselves sound terrific! I don’t really know what’s going on under the hood, but the lowpass filter is especially resonant even with the “Reso” knob all the way down, and the Bandpass and Highpass filters are also exceptional.

There are two grey “Tempo Tap” buttons at the very top of the Predelay / Feedback Delay Time subsection, which I first overlooked because the label appears underneath the backlit Time Value display. The cool thing is that you can tap in separate delay times in “Tempo Sync” mode when the two channels are unjoined. Although, when Tempo Sync is switched off, you can set delay time in milliseconds when designing chorus and flanger effects, but I’ll go into more detail about that later.

The Overdrive module offers three controls: Preamp, Color and Gain. The saturation stage is absolutely beautiful, and the coloration sounds very natural as opposed to the painfully harsh and brittle high-end typically produced by digital distortions. If you tweak the Preamp and Gain controls in tandem with the Limiter Threshold and Output parameters in the Master section, you can dial in some really tasteful saturation. You can even use Sigmund primarily as a distortion plugin with a very slight delay time in order to create a subtle “Haas” effect, which will add some beef to your overdriven signal.

There are also Feedback controls in the Delay subsection next to the Overdrive module, with a “Hold” button that will momentarily sustain the feedback at its maximum value, which is especially cool when you map it to your MIDI sustain pedal. The “Spread” knob in the Delay subsection basically offsets the delay time for both the left and right or mid and side channels, depending on whether or not you’re in L/R mode or M/S mode.

The Modulation subsection routes modulation to three targets: Time, filter frequency Cutoff and Tremolo, which is basically just amplitude modulation. There are two buttons enabling you to switch between Linear and Logarithmic scale modes for the Time parameter, which will modulate the overall delay time in very different ways. I find that a Logarithmic scale is more audible, especially when designing flanger effects with a bunch of feedback. However, if you’re going for a nice, subtle chorus effect, you might prefer Linear mode.

I think it would’ve been nice to be able to route either of the two Modulators to each of the three targets individually instead of routing them to all three at once and then scaling the amount of modulation with three controls for each target, but I really can’t complain, being that Sigmund offers far more modulation options than I could ever have hoped for in a delay plugin. The two Modulators have three types: LFO, Envelope and a Peak Follower, making for some wonderfully spontaneous articulations by tracing the the input signal as a modulation source. I won’t bother indexing the various sync and time signature controls available within each of the three modulator types, but I will tell you that your needs are most certainly met, regardless of what you might be looking for in a modulation source. It would be nice to have a “Random Glide” shape in the LFO section for designing smooth, organic modulations, but the Peak Follower is quite capable of this.

The Routing section displays a block diagram of the currently selected routing configuration, of which there are nine: Parallel, Serial, Tapped Serial and six “Mixed” algorithms offering several unique combinations that defy classification. Very often, especially for recording guitar, I use multiple delay lines in place of a reverb, which often washes out a signal, so instead I create several delay lines in quick succession, panned apart with loads of filtered feedback. I find that the “Tapped Serial” configuration works best for milking every last drop of feedback out of Sigmund for long cascading guitar swells that roll out into the ether.

The Verdict

I’ve used tons of delay plugins, many of which attempt to recreate the magic of vintage analog effect pedals and/or rack mounted units, often producing horribly digital results. In regard to its overall design, Sigmund doesn’t necessarily set out to emulate any one thing, but it’s obviously an inspired work, giving us everything we’ve grown to expect in a delay plugin, but also taking the extra measure of fine-tuning every last detail in such a way that results in a well-rounded, fully realized product with unparalleled flexibility and a surprisingly transparent sound quality that you simply cannot find in most digital effects.

More info: D16 Sigmund (€69)

The Giveaway

We are giving away one Sigmund license, kindly provided by D16 Group. To enter the giveaway, simply leave a comment below. Please do not post multiple comments or reply to other people’s comments (use the main reply button). The winner will be picked by a random number draw and announced on this page on June 17th.

The giveaway is now CLOSED for new entries. We’re sorry about the late announcement this time – BPB took a short break this weekend. The winner is the 113th comment on this page, posted by our reader MC. Congratulations! :)

We have more reviews and giveaways coming soon, so stay tuned and thanks for reading BPB!

D16 Sigmund Review


Sigmund might just be the single most powerful delay plugin I’ve ever encountered. I’m bloody serious. In terms of flexibility, Sigmund is nothing short of insane!

  • Features
  • Sound
  • Workflow
  • Performance
  • Design
  • Pricing
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About Author

Bryan Lake is a sound designer and a musician. He publishes sound design tutorials and sound libraries on his website Sound Author.


  1. I luv D16 plugs. Please let me have this one for free. I cannot afford to buy any more plug ins right now and i neeeeeeeeed dat delay, baby!!

  2. sounds sexy …from old cheesy sound into clrystalclear hightech but all with really warmth.
    one step closer to my dream of an perfect delay :-)

  3. That’s pretty awesome, and I’m glad Mac OS is supported — So many of your awesome free plugins are Windows based!

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