Stacks FX’s first delay pedal harnesses the power of light

Rather than using a pot to control delay time, the Thsee Anomaly uses an LED and LFO—and the results are out of this world.

Stacks FX Thsee Anomaly
When you purchase through affiliate links on Guitar.com, you may contribute to our site through commissions. Learn more.

Stacks FX’s first-ever delay pedal, the Thsee Anomaly, is a mind-bending stompbox that isn’t content with sticking to the rules.

At the heart of the pedal is a PT2399 chip, which is fairly standard in many digital delays. But the boutique maker took the chip’s tendency to degrade signals at longer delay times, and ran with it. So while the pedal’s delay can go up to 1,000ms, don’t expect pristine reproductions of your notes.

And to add even more chaos to the mix, the Thsee Anomaly doesn’t use a potentiometer to control delay time—it uses light. Specifically, a photo-coupler cell (usually found in tremolos and vibratos), an LED and the unit’s LFO section. Tweak the LFO’s parameters—such as depth, wave type and speed—and hear the delay take on chorus, pitch-shifted and vibrato elements. Push it even further and you’ll arrive at weird oscillating sounds.

“The photo-coupler cell is paired up to a light source. In this case, an LED,” Stacks FX explained. “That LED is fed power from the LFO section, specifically the ‘Depth’ pot. Once you start to adjust the depth, the voltage fed to the LED varies, causing the LED to flash. This changes how much light the photo-coupler cell receives, and ultimately changes how much resistance is fed to the delay control.”

Hear the Thsee Anomaly in action here:

For more information, check out stacksfx.com.

Related Brands

Related Tags


The world’s leading authority and resource for all things guitar.

© 2024 Guitar.com is part of NME Networks.