Here’s an American Electro-Harmonix Doctor Q Envelope Follower. Made in the late 70’s, along with its bigger brother the EHX Zipper, both possibly inspired by the legendary Musitronics Mu‑Tron. They are often referred to as auto-wahs but they are much more than that. The filter kicks in when the input signal reaches a certain threshold and then sweeps until it tails off. Envelope followers are not for everyone. Used sparingly and skilfully, they can provide a fascinating sonic excursion, especially when combined with other effects such as echo and/or fuzz – pure ‘70s vibes. Even though the Doctor Q’s abilities are restricted by just 2 external controls, it can produce some great vintage filter sounds at the click of a footswitch.

A002.1

This item is sold As-Described

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Listed5 months ago
ConditionVery Good (Used)
Very Good items may show a few slight marks or scratches but are fully functional and in overall great shape.Learn more
Brand
Model
  • Doctor Q Envelope Filter
Categories
Year
  • late 1970’s
Made In
  • United States

Product safety information may be available here.

Varitone Vintage

Placentia, CA, United States
Joined Reverb:2022

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