The Ashdown Doctors Note is an analog envelope filter pedal designed for bass guitar, made by Ashdown Engineering. An envelope filter opens and closes a tone-shaping filter automatically as it tracks how hard you play, producing the auto-wah and quack effects heard in funk and fusion bass lines. Ashdown pitches it as "bursting with analog envelope filter tones designed for bass guitar," aimed at "allowing the funk to pour from your finger tips."1
The controls: Mix, Sens, Decay and Q
The Doctors Note keeps its front panel to four knobs, which Ashdown describes as simple rotary controls that let you dial in and set the oscillating frequencies with ease.1
| Control | What it does |
|---|---|
| Sens | Controls how the effect reacts to your playing1 |
| Decay | Sets the length of time the effect is active1 |
| Mix | Adjusts the blend of clean and effected signal1 |
| Q | Sets the band width the effect covers1 |
The Sens and Decay knobs together shape the envelope, the part of the circuit that listens to your attack and opens the filter in response. The Mix knob lets you keep some clean low end underneath the filtered signal, which is often how bass players keep a filter pedal sitting well in a band mix. The Q control sets how wide a slice of the frequency range the filter covers, which is the difference between a subtle sweep and a pronounced, resonant wah.1
Build and bypass
The pedal is housed in what Ashdown calls "a custom designed steel casing that will stand up to being stomped on night after night."1 It also features true bypass switching, so the filter circuit is removed from the signal path when the pedal is off.1
Where it came from
The Doctors Note is housed in a custom designed steel casing that, in Ashdown's words, "will stand up to being stomped on night after night."1 Ashdown also describes the pedal's character in playful terms, saying it is built for "allowing the funk to pour from your finger tips."1
For more on how filter pedals work and how they compare, see Filter Pedals and Bass Pedals.
Videos
Ashdown Engineering
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Questions
Is the Ashdown Doctors Note true bypass?
Yes. Ashdown states that the Doctors Note features true bypass switching, so when the pedal is off your bass signal passes through without the filter circuit in the way. That matters on a bass rig, where keeping the low end intact between the instrument and the amp is a common concern.
Is the Ashdown Doctors Note analog or digital?
The Doctors Note is an analog pedal. Ashdown describes it as bursting with analog envelope filter tones designed for bass guitar, and it is built as a dedicated analog filter rather than a digital multi-effect or modelled envelope.
What does the Q knob do on the Doctors Note?
According to Ashdown, the Q control sets the band width the effect covers. In practice it shapes how broad or narrow the filtered band is, which changes how pronounced and resonant the filter sweep sounds as it tracks your playing.
What does the Decay control do on an envelope filter?
On the Doctors Note, Ashdown describes the Decay control as setting the length of time the effect is active. Together with the Sens control, which sets how the effect reacts to your playing, it determines how long the filter sweep hangs on each note before closing again.
Is the Ashdown Doctors Note part of the Dr. Green range?
Yes. The Doctors Note was introduced in January 2013 as one of five hand-made Ashdown Dr. Green bass pedals, alongside the Bearded Lady, OctaDose, Bass Verb and The Aspirin, as reported by Delicious Audio.
Sources (1)
- Doctors Note, Ashdown Engineering
