Forget space-cadet sounds. This road-tough envelope filter is all about dialing fat funkiness with minimal hassle.
Recorded direct into Avid Mbox into Logic X using Sandberg T5..
Clip 1 - Low filter engaged
Clip 2 - High filter engaged.
Clip 3 - Both filters engaged.
RatingsPros:Excellent build. Simple design. Practical sounds. Cons: No blend control. Big footprint. Street: $299 Ashdown Type 23 ashdownmusic.com | Tones:  Ease of Use:  Build/Design:  Value: |
Over the last 20 years or so, Ashdown has carved out a nice niche in the bass universe with amps that have become fast favorites with some pretty high-profile rock bassists. When first introduced, the company’s ABM amplifier series proved Ashdown had the skill and R&D to create products that sounded like nothing else on the market at the time. Knowing what the company has been and continues to be capable of, I was excited to check out a recent addition to Ashdown’s ever-growing pedal line: a new envelope filter called the Type 23.
Brick House
There’s no getting around it: This pedal is heavy and big. Even more striking, initially, is that the only things on the almost 1 1/2-pound pedal’s face are a knob, a toggle, and a footswitch. The vintage nerd in me nodded and smiled while feeling the pedal’s weight and gazing at its simplicity.
The 3-position rocker switch selects the filter frequency: high, low, or a mix of both. The rotary control manages the filter’s sensitivity. There’s also a switch on the bottom of the pedal that lets you further tailor the chosen filter-oscillation frequency. With just a few options to manipulate the tone, however, one can’t help but be curious how many varieties of funk the pedal is actually capable of putting out.
From Swish to Swosh
What was evident after only 30 seconds of playing is that the Type 23 has no intention of being a traditional envelope filter. When the sensitivity is set all the way down, a typical filter pedal only lets a sub signal through—barelyenough to discern any kind of pitch. The Type 23 is not like that. Not at all. Instead, it has a very midrange-forward, nasal-y-ish personality across all the settings, which allows the pedal to stand its own sonic ground, even with numerous other instruments surrounding it.
With the filter frequency switch on the low setting and the sensitivity control at noon, the filter produces a clear, punchy tone with strong fundamentals from the still-present clean tone. The most prevalent sound is a loud swishthat surrounds the note and lands like a small, high-pitched UFO after cutting the note off. If you want less of it, simply dial the sensitivity back to 9 o’clock, where a very vocal, almost talk-box-like tone occurs.
Setting the frequency switch to high and returning the sensitivity control to noon, a lower-voiced tone makes an entrance, with an extra-aggressive midrange normally only achievable through use of distortion.
The pedal does a great job of maintaining fundamental lows when engaged, and I found that the middle position (when used with a direct signal on a separate channel) provides a subtle but perfect amount of funkiness to sit comfortably with other instruments in the mix for an entire song—not just as an effect to turn on, say, for a solo. This gives it tremendous potential as a tool in the studio.
The Verdict
Instead of an envelope filter with a ton of spaced-out-sounding effects one may never use, Ashdown’s Type 23 presents us with a few very usable ones. The extremely simple layout makes for lightning-fast tweakability, and the old-school solidity in the build department makes for a good, modern replacement for those of us who have had to rely on more fragile vintage filters on tour. If you’re willing to sacrifice a chunk of pedalboard real estate, the Type 23 is a strong candidate for a funky new occupant.
A streamlined synth pedal and its accompanying app open up a treasure trove of guitar-synth possibilities.
RatingsPros:Neuro app is fun and intuitive. Streamlined control set. Easy preset switching. Cons: Classic synth sounds can be hard to generate. Little control beyond Neuro app. Street: $239 Source Audio C4 Synth sourceaudio.net | Tones: Ease of Use:  Build/Design: Value: |
My musical predilections and processes typically favor crude, old-world technologies. When recording and manipulating music digitally, I typically sabotage anything too precious with analog pollution. Given that, I’m always pleasantly surprised at how much I enjoy working with Source Audio’s digital effects editing tools.
Source Audio’s primary digital editing tool is called the Neuro app. It’s available for desktop, iOS, and Android applications. You don’t have to use it to make pedals like the company’s True Spring reverb sound great. But it’s easy to use when you want to customize a Source Audio pedal with a tweak that makes it your own. In the case of the new C4 Synth, that’s a good thing, because you’ll definitely want to dive deep into the customization possibilities the Neuro app can unleash. You can also use the app to easily share and download presets from other users.
Don’t Fear the Neuro
The C4 is, to a significant extent, the work of Source Audio chief sound engineer Bob Chidlaw, who has a deep affection for synthesis and a sprawling array of Eurorack modular synthesizers in particular. Modular synthesis is not for chickens. In complex synthesizer arrays you either have to approach the process with a neophyte’s recklessness—happy for whatever randomness your synthesis solution yields—or attack it with the rigor of a lab-coated brainiac. The beauty of the C4 and the Neuro App is that it, too, permits both approaches: enabling disciplined sound sculpting or random tweaking at the app level, as well as more limited tailoring options on the pedal itself.
Perhaps more than any other Source Audio pedal, the C4 relies on the Neuro app. Source Audio opted for a streamlined pedal interface with just four knobs: an input level control, a wet/dry mix, a toggle that moves between three top-level presets, and two “control” knobs that change function depending on how you assign them. The minimal control set means the lion’s share of twiddling is done at the app level.
The Neuro app interface for the C4 is complex. But it’s also fun and inviting. The ease with which you can navigate controls for the four voices, filters, envelopes, LFOs, sequencers, and more is a testament to the interface designers at Source Audio. And while it helps to have a background in synthesis to move around the interface and understand signal flow, it readily rewards casual, intuitive navigation.
Seek and You Shall Search
Conjuring exactly the sound you need on the C4 isn’t always easy. And with four voice generators that can be set for nearly four octaves in either direction, and powerful processor, envelope, LFO, and sequencing sections, you can get bogged down in options fast. But even when I kept things simple and used a single voice, a sine wave, and very basic filtering and LFO settings, it wasn’t easy to get a simple flute tone the way I would with my old Korg MS-10 or a Minimoog. Much of this limitation is down to the way a guitar signal, with its tangle of harmonics and peaks, interacts with synthesis. Such randomness is half the fun of the C4. But you should be prepared to create sounds akin to a space gamelan or alien sitar, with odd attack and decay qualities, rather than luscious beds of future-medieval oboe with predictable decay properties. An oscillator-driven keyboard synth, the C4 is not.
To the extent the C4 generates fatter sounds (often from big, compound four-voice settings), they tend to align with the sonorities of EDM. If you’re on the prowl for more classic sounds, simpler is better, and starting with a single voice and a fairly regular waveform is a good start point for approaching the C4 and Neuro app’s capabilities anyway. But if it’s vintage Pink Floyd and Tangerine Dream textures you hope to extract from the C4, the search can be tricky. Thankfully, Source Audio makes it simple to share presets, effectively creating a community of artists, some of which may be more adroit at fashioning old-school sounds.
The Verdict
The C4’s sound-generation capabilities often seem to verge on the infinite. And when you factor in the inevitable randomness created when guitar signal meets synthesis, that’s probably true. For all its expansiveness, the C4’s voices still tend toward the modern digital-synthesis palette. Framed within a more complex musical piece or a band arrangement, these sounds can be everything from gentle bubbling background atmosphere to smack-you-silly musical exclamation points. But if you’re new to guitar and bass synth or the world of sound design through synthesis, the C4 and the Neuro app can open up a near-limitless world of exploration.
Unusual, dirty harmonic tremolo tones and more from a most unorthodox modulator.
RatingsPros:Many unexpected, unusual, and useable tremolo tones. Many options in a compact box. Tap-tempo control. High-quality build. Cons: Overdriven voice leaves less room to enjoy harmonic tremolo subtleties. Street: $199 Coppersound Loma Prieta coppersoundpedals.com | Tones: Ease of Use: Build/Design: Value: |
Harmonic tremolo, the kind that makes brownface Fender amplifiers the subject of lust, is addictive stuff. I love optical and bias tremolo too—the former for its percussive throb and the latter for its smooth, round pulses. But in the wee hours, when you get into meditative tête á tête with your amplifier and look for your tremolo to take you to another dimension, the warbly, immersive undulations of harmonic tremolo can be powerfully transportive.
Coppersound’s Loma Prieta analog tremolo features two tremolo types. The first is an optical-sounding mode called traditional tremolo. But it’s the wobblier harmonic tremolo setting that is the Loma Prieta’s star. Combined with the pedal’s overdriven fundamental voice, an additional gain control that dirties things up further still, and a waveform selector, it adds up to an unorthodox tremolo.
Rigged to Rumble
Coppersound’s overdriven tremolo concept dates back to the company’s earliest experiments with the effect. And while they considered a cleaner voice, they worked their way back to a dirty tremolo design as Loma Prieta came together. It’s an interesting idea. It also yields some pretty funky colors.
There’s always some quantity of dirty signal in the Loma Prieta’s output, so at times it colors your signal in the way a small, saturated tremolo amp like a Fender Champ, Gibson Skylark, or Danelectro DM-10 might. When you add extra gain from the grit control, the Loma Prieta can also take on overdrive qualities reminiscent of direct-to-desk preamp distortion. If you’re used to tremolo pedals that sound uniformly clean, these tones can sound unusual, and even harsh at some settings. But as you get a feel for the way the volume and grit controls interact, and how the Loma Prieta responds to guitar input and amp characteristics, you uncover many very cool and unique overdrive sounds that can give distinct, uncommon shape to rhythm parts, solos, and hooks.
In smaller amps, the Loma Prieta’s overdrive can sound natural, organic, and of a piece with the tremolo pulses. With larger amps results can vary. A silverface Bassman with 12" speakers flattered the fizzier, direct-to-desk-like aspects of the Loma Prieta’s overdrive profile, especially at advanced grit settings. Paired with 10" speakers, I heard a less cohesive amp/effect whole. I suspect, though, that the Loma Prieta’s basically dirty tone benefits from extra low-end ballast that lends contour to the pulses and counterweight to dirtier sounds. Your results may vary. But if your experience is at all like mine, you’ll find a lot of depth and unexpected textures in the Loma Prieta’s voice. It works dynamically with guitar tone and volume controls, and there are many shades of distortion in the interactions between the pedal’s volume and grit controls alone. If you like the more off-kilter tonalities of Daniel Lanois, Tchad Blake, and early Neil Young, you’ll find lots to dig here.
Many Wobbly Roads to Wander
Unusual overdrive characteristics aren’t Loma Prieta’s only path to unique tremolo colors. The 4-way waveform-shape selector offers sine, square, ramp-up, and ramp-down triangle waves. Predictably, perhaps, the smoother sine wave was best for revealing the harmonic tremolo’s intricacies, while the square wave was ideal for accenting the traditional trem’s choppier signature. But there are awesome and surprising sounds everywhere among the possible combinations. Loma Prieta’s shift function will probably be used primarily to enable the useful tap-tempo capability. But the rate-doubling mode, lo-fi mode (which strips bass frequencies), and distortion setting (which momentarily adds a huge bump in gain and level) all offer quick blasts of drama for twisting already-twisted modulation settings. And the expression pedal option for controlling rate offers yet another path to deviant tremoloisms.
The Verdict
I’m almost reluctant to highlight the harmonic tremolo aspect of the Loma Prieta’s design, because the associations with super lush and dreamy modulation is so strong. The Loma Prieta has those qualities, but nearly every available texture is colored to some extent by the pedal’s unique overdrive and distortion signatures, which will make the pedal sound less lush and dreamy to a lot of players. These sounds will not be to everyone’s taste. And while I came to love and feel very inspired by these tones over my time with the pedal, they offer little leeway for exploring the more pristine side of the harmonic tremolo effect. In that respect, the Loma Prieta is a bit of a niche effect, and perhaps a touch expensive for it. But that niche is hardly a measure of the number of available tremolo sounds, nor of how very engaging and inspiring they can be. And if the same-old-tremolo blues has you down, Loma Prieta is a fascinating possible fix.