Electro-Harmonix Doctor Q (1977)

A Classic Envelope Filter

Pedals like Doctor Q are a bit of a curiosity within the vintage market.
Built at a time when the battle between the wah-wah and the envelope filter was still going, it’s a great example of a good effect that has more or less fallen by the way-side in recent years.
That’s not to say you won’t find auto-wah pedals on the market. Pedals like Boss AW-3 – a basic auto-wah with little to no bells or whistles – are decent enough, but at the same time, they’re not particularly special.

When you get right down to it, modern auto-wahs tend to be a pretty vanilla take on this effect. Yes, they’ll give you an auto-wah of sorts, but they won’t do anything all that special with it.
If you want really nice envelope filter, then your best bet is to hop on to the second-hand pedal markets and find yourself a Doctor Q

Why Buy an Auto-Wah?

Everybody loves a classic wah-wah pedal.
For many people, the Dunlop Cry Baby is simply a must-have effect, and it’s easy to see why. By giving the guitarist manual control over the effect, the wah-wah offers a unique kind of frequency modulation, unlike most other pedals.
That being said, as a totally manual pedal, it demands rather a lot of the guitarist’s attention. It’s not exactly difficult to use, but there’s a knack to it that can distract from playing.

The auto-wah – also known as an envelope filter – seeks to solve this problem by handing control back to the pedal. While it can’t offer quite the same natural, voice-like sound as a classic wah, the effect of the Doctor Q – and other auto-wah pedals – works well to simulate that sound in a way that takes the pressure off of the player.

Is Doctor Q Right For You?

At the end of the day, even when this pedal was made, envelope filters weren’t as popular as wah-wahs, but that’s not to say they weren’t used. Can you imagine genres like funk and disco without the sound of the auto-wah? We don’t think so.

The Doctor Q is a smooth envelope filter with a gorgeous tone. With its versatile range of effects, this pedal will give you sounds you never knew you wanted, transporting you straight back to the ’70s.

Of course, words don’t do it justice. If you really want to get a sense for what this pedal can do, then take a minute to check out the Doctor Q from Electro Harmonix here on Tonepedia. You won’t be disappointed.

Electro-Harmonix Doctor Q (1977) technical specifications

Manufacturer Electro-Harmonix
Made In USA
Year 1978
FX Envelope Filter
Type Pedal
Jacks mounted on Top
Bypass Buffered Bypass
Battery? Yes
Voltage 9
Polarity TRS
Circuit Analog
Tube equipped? No
Weight (in kg) 0.65
Width (in cm) 8.5
Height (in cm) 5.5
Depth (in cm) 13.5

Electro-Harmonix Doctor Q (1977) reviews & comparison videos

Doctor Q (1977) reviews & comparison

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