Mod Squad: 4MS Mattias Puech Tapographic Delay

Put your finger on the pulse of your music.
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In addition to enhancing drones or adding room-like ambience to your music, a delay effect can be used in a variety of creative ways within a patch, particularly when you have CV control over its parameter. And like most effects, every delay—analog or digital—has its own sound and playability characteristics.

The Tapographic Delay
 uses DSP (with 16-bit, 48
 kHz resolution and 32-bit
 floating point processing)
 to do everything it does in
 an affordable way behind
 an 18 HP panel.

The Tapographic Delay  uses DSP (with 16-bit, 48  kHz resolution and 32-bit  floating point processing)  to do everything it does in  an affordable way behind  an 18 HP panel.

Created in collaboration between 4ms and Matthias Puech, the Tapographic Delay (TD) combines a powerful mono-to-stereo, multitap delay system with a uniquely performative interface to control it. By striking the module’s force sensing resistor (FSR) with your finger (or using CV input), you set individual delay taps to create rhythmic patterns in real time. And because the FSR is velocity sensitive, you can individually alter the amplitude or frequency characteristics of each delay tap based on how hard you strike the pad (using the built-in VCA, lowpass filter and bandpass filter).


4ms and Puech refer to a rhythmic delay pattern (including the velocity level, velocity-controlled parameter, and pan position of each tap, which I’ll get to in a moment) as a tapography. For example, if you tap a rhythm of three 8th notes on the FSR, that counts as 3 taps in the tapography. The upper row of buttons acts as a level indicator showing tap velocity, while the Delete/Sync button flashes to show the tapped pattern each time the tapography repeats. In addition, the Gate jack sends a signal for each tap.

The 3-position switch to the left of the FSR helps you create a tapography. Use the Add setting to lengthen the tapography as you strike the FSR (or send the Tap input a trigger). The rhythm you hear as the delay repeats will depend on the Time setting, but as long as you’re in Add mode, you will continue to extend the length of the tapography until you exceed the memory. (The manual likens it to increasing the length of tape in a tape loop.) The TD provides delay times up to 172 seconds ( just shy of 3 minutes).

Next, you can set the switch to Off (disengaging the FSR) or Ins to set the length of the tapography. Using Ins mode, you can enter more taps within the tapography, but it won’t add any length to the loop you’ve captured. The red LED above the FSR flashes each time the loop wraps around.

A tapography can have up to 32 taps. If you exceed that number, you begin sacrificing the earliest taps each time you enter a new one. The module can store and recall 24 tapographies, which you access using the upper row of buttons: There are 4 banks with 6 slots in each.

In Sequencer mode, the TD plays through the stored tapographies within a bank, using either the FSR or a trigger to change to the next one. There are three directions you can move through the bank: forward from slots 1 to 6, which then wraps around and repeats; jump randomly through the bank; or step randomly to adjacent slots in either direction.

The Morph control sets the amount of time it takes to transition into the new tapography, maxing out at around 12 seconds. You can further alter the transition using the velocity level of an FSR strike (higher velocity levels shorten the transition time) or based on the voltage level sent to the Velocity/Morph jack (higher voltage levels increase the transition times).

The TD includes 18 presets within the first three banks, which demonstrate some of the not-so-obvious things you can do with the TD (such as unusual bouncing patterns and rhythm bursts). And you can use the presets to practice combining Sequencer mode with the Morphing controls, and the various tempo and sync features. In addition to having the fourth bank open for your own tapographies, you can overwrite any of the presets.


On its own, the setting of the Time control will scale the tap times in your tapography (from 0.1 to 4), whereas in Sync mode it determines the multiplier/ divisor based on the signal patched into the Ext Clock jack. While you’re working with your delay pattern, you can alter the Time level using the knob or a bipolar CV input: As the Time value changes, you’ll hear tape-delay-style pitch shifts.

Firmware version 1.1 adds a Quantization mode that aligns your taps to an external clock input. If you then change the external clock speed, the new tempo will not affect the taps you’ve already added; it will quantize the subsequent taps to the new tempo. (Updating the firmware is as easy as holding down two buttons when powering up the module, then playing a WAV file downloaded from the 4ms website into the Audio In jack.)

To further warp your sounds, the TD includes built-in LFOs for modulating the pitch of each individual tap using a randomized, sine-like waveform. The LFO frequency ranges from about 0.1 seconds to 50 Hz, though the frequency amount is so low at either extreme of the Modulation knob that you don’t hear the affect. Turn the knob (or patch a CV into the bipolar Mod input) to go from subtle wow-and-flutter effects to severe pitch swoops.

And, as you would expect in a delay, the TD has a Feedback control (with an accompanying bipolar CV input). Better still, the feedback has a maximum level of 120 percent: Use that power wisely!


4ms and Puech have put the the FSR’s velocity sensitivity to use in other ways of shaping the sound of each tap. The intensity level of each finger strike (or the combined signals going into the Tap and Velocity/Sync jacks) can change the amplitude or filter response of the delay taps based on how the switch on the lower right is set. Amp mode is used for adding dynamics to each tap, whereas the LPF (lowpass filter) and Res (resonant bandpass filter) settings alter the frequency characteristics of the taps by changing the lowpass frequency cutoff and bandpass Q, respectively. This allows you to shape your delay patterns dynamically and spectrally from within the module itself. For example, feeding the module a quarter-note kick pattern, I was able to create a groove with a wide range of timbres simply by using the filter settings.

How the filters and Amp behave depends on the velocity-level setting. There are five velocity levels to choose from, and they affect the Amp and LPF differently than the resonant bandpass filter. To get the widest amp dynamics and lowpass filtering, velocity needs to be set at minimum, whereas the Q of the bandpass filter responds best to higher velocity settings. Unfortunately, this is a global setting, so a Medium level is the best choice if you want to use all three settings in delay rhythm.

Because the velocity level you tap is stored in the tapography, you can change the velocity setting in the menu as your pattern repeats to alter the dynamics and spectrum—a workaround that can be used in performance (though it would be nice to be able to set individual velocity responses for each filter and the amp).

The TD also offers three panning modes: Alt mode alternates each tap between the left and right output; Rnd mode places each tap randomly across the stereo spread; and Sum/Repeat gives you a summed mono signal at Output 1, and send the final tap in the delay line to Output 2 without filtering. You can press Rnd as your tapography is playing and reassign the taps to different spots in the stereo spread until you find your favorite; then save the tapography to lock it in for later recall.


If this seems like a lot to remember, it is. Like other 4ms modules, the TD is packed with so many features that the buttons and switches do double-duty. Fortunately, the panel layout—with the menu printed at the top—is logical, and the manual clearly explains what everything does: Read it if you want to get the most out of this module.

The most challenging part is not in utilizing the TD’s features, but in accurately tapping in the rhythms you want. Fortunately, if you make a mistake, pressing the Delete/Sync button will remove the most recent tap. And you can successively undo each of the previous taps with additional short presses of Delete.

Two of the most musically useful controls are the easiest to miss: By playing with the Level and Dry/Wet knobs, you can discretely change the perceived rhythm in a tapography. The Level knob only affects what enters the delay: It does not affect the dry signal.

After building up a delay pattern, I would be surprised by the rhythm of just the repeats I’d get when turning the output to totally wet. That can lead to cool remix-like effects, such as turning down Level when the mix is fully wet and letting the repeating rhythm slowly unravel.

The TD is also fun to add into self-regulating patches, particularly when you use the Gate output to affect, say, a clock somewhere else in the signal path, or by stepping through tapographies while putting the Time, Feedback, and Modulation under CV control.

The most important thing to remember is that the Tapography Delay was designed for real-time performance. While it’s perfect for use as a traditional delay, its unique feature-set will likely take you down more unexpected paths each time you use it.