TLN-156 Neural Agonizer


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Last updated: March 14, 2017


The TLN-156 Neural Agonizer is a voltage controlled spring reverb processor. Although this module can be used to simulate room reverb with most audio signals, it includes numerous enhancements specifically designed for interfacing to a modular synthesizer. If you're looking for a smooth, natural sounding reverb system to make your synthesizer sound like its being played in the Concertgebouw, then go buy a Lexicon. This is not your grandmother's reverb tank, this is a noxious tool capable of inflicting some serious damage to your audio.

The TLN-156 features: an amplifier for controlling the input signal level, two reverb tanks that can be driven in series or parallel, separate recovery amplifiers and resonators for each reverb tank, a feedback amplifier with lowpass filter, and a deformation processor for combining the reverb tank outputs. Most parameters are voltage controllable and several patch points are available for adding additional signal processing. All inputs and outputs handle 10 Vpp audio signals and 5 volt control voltage signals (modular standard).

Total current draw for TLN-156 is 70 mA @+15V and 70 mA @-15V.

Availability: Sold Out

MOTM-style front panels for this module can be ordered from The Bridechamber and Stooge Panels.


The User Guide does not contain detailed explanations on how to install parts or which kinds of solder to use. The intended audience is the experienced kit builder who is quite comfortable building a circuit from a description, a parts list, and a schematic. Calibration routines are included.

View the TLN-156 User Guide rev 1.1.1 (pdf)

Graze over the TLN-156 Schematics rev 1.1 (pdf)

Handy panel wiring diagram courtesy of Tom Farrand (pdf)

The Accutronics Reverb website has lots of information about their reverb tanks (specifications, mounting details, where to buy, and more). The TLN-156 User Guide contains specific information about selecting suitable Accutronics reverb tanks for the TLN-156.

Pictures & Links

TLN-156_panels.jpg NAfront_s.jpg al_ags.jpg
My build with Stooge Panel Cool panel by Phil Petschke 2U version by Andrew Listmayer

Construction photos

Hints for mounting reverb tanks

Ryan's TLN-156 with Steve Thomas panel

TLN-156 in dotcom format

TLN-156 construction by Tom Farrand

Neural Agonizer discussion on Electro-Music

Neural Agonizer videos by neandrewthal

Sound Samples

These demos feature the TLN-156 in some simple patches that were recorded without any added effects.

  • Sawtooth Drone - An MOTM-300 oscillator is fed into the TLN-156. Four outputs from an MOTM-380 quad LFO modulate: Feedback, Trauma A, Stress B, and the MOTM-300 oscillator frequency (slightly). A Blacet TimeMachine is patched into the feedback loop of the TLN-156 to further obfuscate the source. Outputs are taken from Out A (left) and Out B (right).
  • Bass Pulse - A bass pulse from an MOTM-300 oscillator can be quite boring on its own. But when fed to a TLN-156, it really comes to life. An MOTM-320 LFO modulates Deformation. Two MOTM-800 EGs modulate Feedback and LPF. Two instances of this patch using slightly different LFO frequencies are presented for your stereo listening pleasure.
  • Twain Twain - Pink noise is fed into a TLN-156. The VIBRATO output from an MOTM-101 S&H modulates the Drive signal. Vastly different settings for the Stress and Trauma controls on the A and B channels produce different sounds while they undergo slight modulation. Outputs are taken from Out A (left) and Out B (right).
  • Great Caesar's Ghost - A lightly filtered sawtooth wave isn't very scary on its own. Processing it with a TLN-156 and a Blacet TimeMachine in the feedback loop produces remarkably terrifying results. Output is taken from Mix Out.
  • Feedback Effects - A sawtooth wave from an MOTM-300 oscillator is fed into the TLN-156. An MOTM-800 envelope generator fed to the Drive input produces short bursts of sound. The A and B Stress controls are slowly modulated over a 1 minute period. Random modulation is applied to the Feedback and LPF inputs to create ringing tones in response to the sawtooth bursts. Outputs are taken from Out A (left) and Out B (right).
  • Collage - Three sounds are sequenced in this demo. The first sound is a SINE wave sweep over the audio range with outputs taken from Out A and Out B. The second sound is the same SINE wave sweep but with an Oakley Equinoxe phasor patched into the feedback loop and modulation applied to the Feedback and LPF inputs. The third sound demonstrates the Deformation processor as a voltage controlled mixer. Two MOTM-300 oscillators are patched into the In A and In B jacks on the TLN-156. An LFO modulates the mix between the two oscillators as the LFO frequency is swept from high to low. The voice over track is simply audio patched into the TLN-156 with no modulation applied.