Offer Details

Used
Mad Professor Deep Blue Delay Effects Pedal – Used
A BJF-designed ambient delay pedal with an analog direct signal path, tape echo-voiced repeats, 25–450ms of delay time, and no noise reduction — three knobs, remarkable tone, and natural organic decay that earns its reputation on every pedalboard it lands on.

Used Item. This pedal is sold as used. Power supply is not included — the Deep Blue Delay requires a standard 9V DC center-negative supply (8–15V range accepted) or a 9V battery. Questions about condition? Call or text us at 814-371-5666 before purchasing.

About This Pedal
The Mad Professor Deep Blue Delay comes from Finnish designer Bjorn Juhl — BJF — whose approach to pedal design consistently prioritizes how something sounds over how many features it has. The Deep Blue Delay is that philosophy made into a delay pedal. Three knobs. No tap tempo. No preset slots. No modulation switch. What it has instead is an analog direct signal path that adds no filtering or coloration to the dry tone, a digitally processed echo signal that has been carefully filtered and voiced to behave like a classic tape echo unit, and a repeat formation that was specifically designed to sound musical even when the delay time is not perfectly locked to the beat. That last detail is a meaningful real-world advantage — it is the reason the Deep Blue Delay sounds good at a wider range of settings than many more complex delay pedals. The absence of noise reduction circuits is also intentional: Mad Professor kept them out specifically to preserve the natural decay of each repeat, letting the echo tail roll off organically the way a tape echo does rather than cutting off cleanly the way noise-gated digital delay repeats tend to do. This used example brings all of that to your board at a price that reflects its pre-owned status, not its sonic quality.

Key Highlights

BJF (Bjorn Juhl) design — the same designer behind some of the most respected boutique pedal circuits of the last three decades
Analog direct signal path — short signal route through analog amplifiers with no filtering, zero tone coloration on the dry signal
Tape echo-voiced repeat character — tuned filtering on the echo signal produces natural, organic decay without noise reduction artifacts
No noise reduction circuits — repeats decay naturally, maintaining the character of a vintage tape echo rather than cutting off abruptly
Delay time: 25ms to 450ms — covers slapback, rockabilly echo, ambience, and longer atmospheric repeats
Level control: blends dry and delay signal from fully dry to full wet delay
Repeat control: from a single repeat at minimum to infinite regeneration and self-oscillation at maximum
Designed to work well with distorted tone — can be placed before or after drive pedals without degrading the delay signal
Can be used in front of an amplifier or in an amplifier's effects loop
Complete true bypass — input grounded when in bypass mode
Compact format: 69mm x 111mm x 50mm including jacks and knobs
Input impedance: 180K Ohms. Output drive capability: 10K Ohms
Signal to noise ratio: 80dB
Maximum input voltage: 2V peak / 650mV RMS
Current draw: 25–32mA at 9VDC depending on delay setting. Voltage range: 8–15V DC
No tap tempo — delay time set manually via Delay knob

The BJF Difference
Bjorn Juhl's designs are known for sounding more musical than their spec sheets suggest they should. The Deep Blue Delay is a good example: its repeat formation was specifically designed to not require precise beat-locking to sound good at longer delay times. Rather than giving the full range of repeats that would create rhythmic clutter when slightly off the beat, the voicing pulls back in a way that stays musical and ambient across a wider range of timing settings. It is a design decision that is invisible until you start playing — and then it is obvious.

Tape Echo Character Without the Tape
The echo signal in the Deep Blue Delay is filtered and voiced to approximate the bandwidth and tonal decay of a vintage tape echo unit. That means repeats that get progressively darker and softer with each generation — the way a real tape echo works — rather than bright, clean-sounding digital echoes that maintain their character all the way to the last audible repeat. The absence of noise reduction keeps this decay trail natural and smooth rather than mechanically truncated.

Works With Distortion
Most delay pedals degrade noticeably when placed in front of a driven signal or after heavy distortion. Mad Professor specifically engineered the Deep Blue Delay to handle both positions — before or after drive — without the echo signal becoming muddy or the dry signal losing clarity. For players running dirt first and delay after, or who want a single-repeat ambience behind a high-gain lead tone, this distinction matters in practice.

Great Fit For

Players who want an ambient, tape-echo-voiced delay with a simple control set and exceptional sound quality
Guitarists who prefer to set delay by ear rather than by tap tempo and want a pedal that rewards that approach
Blues, country, and classic rock players looking for slapback, single-repeat ambience, and subtle echo tones
Pedalboard builders who want a high-quality, small-footprint delay that fits alongside overdrives and boosts without taking over
Players running distorted or high-gain tones who have struggled to find a delay that sits correctly in that context
Anyone looking to add a boutique Finnish-designed delay pedal to their rig at a used price

Sound and Feel
The Deep Blue Delay occupies a specific tonal space that a lot of players are searching for without always knowing how to describe it — a delay that feels like part of the guitar rather than an effect added on top of it. The analog direct path preserves the character of the dry tone entirely, and the voiced repeat signal blends in underneath it in a way that adds dimension rather than clutter. At minimum Repeat with Delay set below 120ms, the result is a clean slapback ambience that makes single-note lines breathe and chords bloom without anything obviously echoing. Running the Repeat control further up with a longer delay time produces the sustained, fading-into-the-room quality that players associate with vintage tape echo on recordings from the 1950s through the 1970s. At maximum Repeat, the pedal feeds back into self-oscillation — a useful experimental territory for players who work in noise or ambient contexts. The Level knob is a blend control that ranges from entirely dry to fully wet, which gives precise control over how present the delay is in the overall mix at any setting of the other two knobs.

Specifications

Designer Bjorn Juhl (BJF)
Delay Time 25ms – 450ms
Controls Level, Delay, Repeat
Direct Signal Path Analog, No Filtering
Noise Reduction None (intentional)
Bypass Type True Bypass (input grounded)
Tap Tempo No
Signal to Noise 80 dB
Input Impedance 180K Ohms
Output Impedance 10K Ohms
Max Input Voltage 2V peak / 650mV RMS
Current Draw 25–32mA (delay-setting dependent)
Voltage Range 8V – 15V DC (below 7.5V delay mutes)
Power Jack 2.1mm center-negative DC
Dimensions 69 x 111 x 50 mm (incl. jacks and knobs)
Condition Used

Pedals with this kind of reputation tend to hold their value and their place on a board once a player discovers what they do. The Deep Blue Delay has been a go-to for players across blues, country, rock, and ambient music for well over a decade — not because it does everything, but because what it does, it does better than most. Three knobs. Remarkable tone. Used price.
Questions about condition or anything on your mind before you pick it up — give us a call or a text. We are always glad to help.
Reach us at 814-371-5666 — Spotts Music Center, Dubois, PA. Helping you make music.