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Welcome
Welcome
I'm a designer and builder of guitar effects pedals, amplifiers, and other pro audio gear. I'm currently hard at work launching my latest designs - the Desktop Pre, a re-imagining of the classic 5F6-A's preamplifier stage, and the Butter Booster, a modern take on the classic boost circuit. Check back soon, follow me on Instagram @oddbirdaudio, or head over to my Reverb store for the latest!
Butter Booster
Butter Booster
About This Pedal:
About This Pedal:
The Butter Booster is my version of the classic Dallas Rangemaster. It features a custom hand brushed finish, durable hand-wired Switchcraft jacks, and a PCB layout for the audio and power circuits to minimize noise. This design accepts a standard polarity (center negative) DC 9V power adapter, and includes an internal voltage regulator that ensures consistent tone and bias regardless of the input voltage (9-14VDC nominal). All switching has been carefully designed to be pop-free, and this pedal is true bypass.
There are three tone presets - Traditional, Modern, and Baritone, plus the Ge and Si modes making for six different tonal combinations:
Traditional (aka "Treble") is the same 2.6kHz corner frequency of the original Rangemaster
Modern (aka "Midrange") drops this an octave to about 1.3kHz. I find it gives it a bit more grit, mellows out the brightness, and works well with newer amplifier designs that may already be shaping the overdrive tone with bright caps or high shelves.
Baritone (aka "Bass") is around 700Hz, coincidentally the same as the Tube Screamer. It has some of the TS character, but clips asymmetrically and has its own distinct flair. Useful for overdriven bass, drop tuning or baritone instruments.
In my testing I found that selecting the right transistor with non-linear gain characteristics matters much more than whether it is Ge, Si, NPN, or PNP. With the proper components any silicon transistor can be made to sound virtually identical to germanium, although the opposite is not necessarily true.
The benefits of silicon are numerous - well-defined gain, low leakage, low noise, low dependence of gain on temperature, and good consistency across batches. The mystique of germanium is undeniable, that's just not what this pedal is about. The Butter Booster is designed to deliver optimal performance and consistent tone in a compact package.
Here's a pretty jam-heavy demo
Here's a pretty jam-heavy demo
Recorded through a clean Fender 5F6-A preamplifier (see Desktop Pre, below) coupled with a Stratocaster run directly into the Butter Booster.ย Some delay in the effects loop can be heard in some takes, this is the MXR Carbon Copy. The combo amplifier features true spring reverb.
It's been through a few revisions
It's been through a few revisions
I started with a 1590LB format. This was fun, but the format was too cramped to easily accomadate new features. Ultimately I redesigned this to fit into the 1590A as seen above.
I did enjoy this design phase. The perfectly square enclosure is oddly satisfying, and the sheer density of internal parts gave it some real weight. It also makes for nicely symmetrical photos, as you can see:
Features:
Features:
Handmade from start to finish
Point to point wiring; true bypass
Each pedal is individually optimized (retrospectively tedious)
Input snubber shunts excess highs to ground
This is a big part of why Ge sounds different - lower bandwidth
Switchable tone shaping - push-pull pot
Very compact - two inches square
Super Saturator
Super Saturator
This low voltage valve clipper was inspired when a friend asked me to create a pedal to give his electric banjo more grit and sustain, especially for finger tapping and solos. He has a very avant-garde approach to bluegrass, running guitar effects pedals with his banjo to create new and interesting sounds. After breaking all the rules of linear design, I ended up with an interesting (if somewhat unrefined) starved-plate triode overdrive reminiscent of a high-gain amplifier. It does have a linear region, but also features some delightfully non-linear effects as the signal level increases.
Essentially the circuit functions as a compressor/limiter at low signal or gain levels, and an overdrive pedal at high gain. Inspired by the gain staging of Marshall amplifiers like the JCM 2000, it also includes a negative feedback loop that changes the "tightness" and feel of the pedal. The application of negative feedback to the input of the clipping circuit also affects the onset of distortion, making it more sensitive to dynamics with a sharper transition between clean and overdrive.
The challenge with banjo is knocking down the sharp transient and bringing out the body of the tone, without introducing pumping or undesirable artifacts from grid current. This means the attack must be fast, giving the pedal limiter-like behavior for a fairly unique sound. The dynamic range of a plucked banjo note is much greater than guitar, and resonates differently as well. Interestingly, due to the resonant head the lowest note on banjo is a subharmonic, lower than any guitar fundamental at about 70 Hz. To accommodate this, the Super Sat has an extended bandwidth for slightly lower lows.
Super Saturator Demos
Super Saturator Demos
Recorded directly into an Mbox 3 Mini, with only moderate band limiting (60 Hz ~ 10kHz) applied in post-processing. The only other pedals in the loop are a Ditto x4 for looping, along with the Tech 21 Boost RVB for a nice medium plate reverb. Aside from this it's just the guitar, into the Super Saturator, and directly into the audio interface.
Next, an overdriven 5F6-A Bassman style preamp is run into a single-ended 6V6 output stage, with tube-driven spring reverb.
Banjo_Combo_Take1.mp4The Desktop Pre
The Desktop Pre
In complement to the Rangemaster, the Fender 5F6-A Bassman and its derivatives set the standard for guitar tones from the 60s and beyond. However, these classic amplifiers are also extremely bulky, heavy, and unnecessarily loud by today's standards. What if you want the sound of the '59 Bassman but don't want to rattle the floorboards and wake the neighbors, fun as that might be?
I set out to recreate the front end of this iconic amplifier in a compact package, with expanded routing options and an intuitive control scheme. Behold, the Desktop Pre (still working on the name). The large gain and volume knobs can be adjusted with the side of your foot while playing. What I call the "patch matrix" allows splitting the effects return signal into mono, stereo, XLR, or "dual-mono" - the stereo jack becomes a second mono out. This allows for direct routing into a standalone power amplifier, mixing board, recording interface, or anything else that accommodates line or mic-level inputs.
Technical ramblings
Technical ramblings
The JTM-45 is virtually identical to the 5F6-A, except for two things - higher gain preamp tubes (12AX7s vs. the Bassman's 12AY7s), and alterations to the tone stack. Jim Marshall also wrapped the power amplifier in 3x more negative feedback to tighten up the feel, but this isn't as relevant when discussing the pre-amplifier section.
In this version I set out to emulate both of these amplifiers in one unit. To create psuedo dual-channel behavior, the gain and tone characteristics of two Soviet 6N2P valves are modified at the flip of a switch. The Clean setting is similar to the bright channel on the Bassman. The Crunch setting is reminiscent of JTM-45 normal channel, which omits the the bright cap for smoother overdrive.
It's still a work in progress but next up on the list! There's much, much (much) more to write on all of these projects. As development continues I hope to share as much as possible! Stay tuned, thanks for stopping by.
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