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CHEMICAL Z™ - Roy Z signature dual channel overdrive

CHEMICAL Z™ - Roy Z signature dual channel overdrive

Regular price $249.00 USD
Regular price Sale price $249.00 USD
Sale Sold out
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Batch #

Pre-Order now.  Limited quantities available. 

First batch should ship on or before the first week of July.  Second batch will most likely ship mid-July.
Once your RZ-01 ships, you'll receive your tracking information.

Roy Z signature
Dual Channel Overdrive

  • Signature overdrive pedal inspired by Maxon OD808, OD808X, and APEX808 circuits.
  • Designed by Tube Screamer creator Susumu Tamura.
  • Features "MagicIC used in APEX808 and Tamura-Mod Tube Screamer mods.
  • Less compression & more even frequency response than a standard 808.
  • Increased output level.
  • Two footswitch-selectable clipping modes
  • NORMAL MODE—for standard 808-style overdrive.
  • HOT MODE—engages alternate diode pair for increased gain, output, and different EQ curve.
  • 9V battery or external power options.
  • True Bypass switching.
  • Made in USA.

"A new overdrive based on the mild, natural drive sound of the legendary TS808, with even harmonics added at lower volume levels than the symmetrical clipping diodes would activate, producing rich integer harmonics.
Equipped with a HOT/NORMAL mode foot switch, both modes have excellent high-mid performance, a transparent, comfortable, and well-defined sound.  HOT mode is a higher gain, sparkling, easy-to-listen distortion for playing solos."
-TS Originator Susumu Tamura / June 7, 2024

Roy Z is a household name in the Metal community.  His extensive resume boasts the privileged position as guitarist, collaborator and producer for the solo sojourns of not one, but two of Metal’s most iconic frontmen – Rob Halford of Judas Priest and Bruce Dickinson of Iron Maiden.

In addition to his work with these vocal titans, Roy has produced over fifty albums for a variety of artists in the hard rock and metal genres.

Most recently, Roy has teamed up once again with Bruce Dickinson on his first solo album in nearly 20 years—The Mandrake Project.

The Chemical Z overdrive was designed to replace Roy’s multi-drive setup with a single pedal that would not just meet all his dirtbox desires, but exceed them.

Designed by Tube Screamer creator Susumu Tamura, the CHEM-Z circuit is based around the “Magic” IC that was only found in limited runs of the best-sounding vintage TS808’s. This IC was also used in the APEX808 that Godlyke released in 2020 under the Maxon Custom Shop banner.

This special OpAmp offers less compression and more output than the typically-used JRC4558. In addition, it produces both even and odd-order harmonics in a similar manner to the preamp & power sections of a tube amp.

More than just a copy of previous designs, Chemical-Z has been optimized for use with high-gain amps. Rich in integer harmonics and with a precisely-tuned upper midrange, CHEM-Z is aggressive yet articulate; edgy yet easy on the ears.

This crunchy clarity not only breathes new life into tube amps, but is also the perfect “plug-in” for adding depth and dimensionality to digital modeling units (Roy uses CHEM- Z to warm up the sound of his Quad Cortex).

Chemical-Z also features a footswitchable hot channel that activates an alternate set of clipping diodes. These now-defunct Panasonic DA2S00100L diodes were used in the Maxon OD808X Overdrive Extreme and have more forward voltage than standard diodes, functioning in a similar manner to the red LED’s that other builders (Keeley, Earthquaker Devices, Fortin, Catalinbread) use in their OD circuits. The result is more gain and output level, but also a noticeable bump to the low-midrange that helps thicken things up for soloing.

This dual-channel design also allows CHEM-Z to be used with clean and semi-clean amps, creating a 3-channel, “clean-crunch-crush” monster rig with just a single pedal.

As with all TWA models, only the highest quality components go into the production of Chemical-Z, including ALPHA potentiometers, Marushin & Neutrik jacks, KOA/Speer resistors and WIMA, Nichicon, Kemet, & Vishay capacitors. CHEM-Z is hand-assembled in the USA using our very own nimble little fingers.

We are once again extremely honored to work with two luminaries in their fields to bring you a pedal that is at the apex of its class. Our heartfelt thanks go out to Roy Z and Tamura-san for partnering with us on this project.

We proudly present to you the Chemical-Z!


Input Impedance: 500k ohms
Output Impedance: 10k ohms or less
Maximum Gain: HOT 27dB @ 2 kHz, NORMAL 23Db @ 2 kHz
Equivalent Input Noise: HOT Typical 106dB / A-wt., NORMAL Typical 104dB / A-wt. Controls: DRIVE / TONE / LEVEL
Switch: True-Bypass switching BYPASS / ENGAGE, MODE HOT / NORMAL 
Power Supply: 9V battery or external power supply 9VDC
Battery life: Approximately 70 hours on a standard manganese battery (Panasonic
6F22) at 25°C / 77°F
Power Consumption: Min. 5 mA at 9VDC (The current consumption will vary depending on the number LED’s in use at any given time).
Dimensions: 120 mm (4.69”)L x 93 mm (3.66”)W x 51mm (2.01”)H
Weight: 369 g (13 Oz) without battery.
Options: POWER-ALL® ECO-DAPTER® - Single Power Supply
*Please note, like all TWA Pedals, the Chemical Z™ will be manufactured in a limited batch of 100.  Unfortunately we are unable to predict exactly when/if a next batch will be manufactured, however if these sell out quickly, we will definitely be making more next year!
*Specifications are subject to change without notice.
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