Denmark regularly tops the list of Happiest Places on Earth. Obviously that’s due to their unusually high number of effects manufacturers per capita. TC Electronic, Emma, Reuss, and T-Rex are a few of the builders that call the nation their home. They have a reputation for building high-quality, no-nonsense effects, and the same is true of Grenå’s East Sound Research, AKA Carl Martin. (The Purple Moon, however, is part of Carl Martin’s Chinese-made Vintage series.)
Nailing the Vibe
Carl Martin’s latest offering is a psychedelic toolkit that combines classic Uni-Vibe tones with blistering silicon fuzz in one bombproof housing. The controls are intuitive and well organized: On the vibe side are knobs for speed 1 and speed 2, with a footswitch to toggle between them and flashing LEDs to indicate their rates. Depth and level controls let you dial in the desired amount of swirl.
Ratings
Pros:
Compact. Well-built. Stellar fuzz. Powerful two-speed vibe.
Cons:
No fuzz without vibe. No expression pedal input or ramp control.
Tones:
Ease of Use:
Build/Design:
Value:
Street:
$148
Carl Martin Purple Moon Fuzz n' Vibe
carlmartin.com
As if wired to do so, I grabbed my Strat to test drive the Purple Moon, but then decided to avoid the obvious. With 1960 Les Paul Reissue and Jazzmaster in hand, I plugged into my favorite new amp, a Dusky D20, and did everything in my power not to play “Breathe” first.
Carl Martin has absolutely nailed the Uni-vibe sound, delivering all the blubbery goodness you’d expect. Remember, Uni-Vibes were developed as “portable Leslies,” so it’s great to be able to approximate the big cabinet’s two speeds, alternating between slow, swirly phasiness and full-on, rotating chop. Since there’s no expression pedal input, it might have been nice to include a ramp-speed control, since that “taxi to takeoff” effect is one of the best things about vibe effects of this type. Not providing it here seems like an oversight.
Serious Sizzle
The fuzz is fantastic. It’s crispy, with the correct quantity of sizzle—which is to say, ungodly amounts. It’s important to note, though, that while the vibe can be used without fuzz, the inverse is not true—there’s no fuzz-only option. It’s a shame, because I love this fuzz! But while I can’t help feeling that Carl Martin has limited the pedal’s usefulness by not providing true two-in-one switching, perhaps it’s best to think of the Purple Moon as a Uni-Vibe pedal that tosses in a bonus fuzz, especially since you get both effects for about the same price as many vibe-only pedals.
At any rate, you can’t argue with the tones. There is a lot of vibe control here, and when the fuzz is engaged the paint-peeling lysergia rating on this thing is a solid 10. (Full disclosure: upon conclusion of this review I totally grabbed my Strat and played “Us and Them.”)
Watch the Review Demo:
Neutrik’s Timbre plug, made for toggling between capacitors.
Let’s begin with some typical additional capacitance values that certain lengths of cable (or capacitors) can bring to your system:
• 10’ vintage coiled cable (approx. 3 meters) -> 1 nF
• 15’ vintage coiled cable (approx. 4.5 meters) -> 1.5 nF
• 20’ vintage coiled cable (approx. 6 meters) -> 2.2 nF
• 30’ vintage coiled cable (approx. 9 meters) -> 3.3 nF
• Ritchie Blackmore-style, ultra-long vintage coiled cable -> 4.7 nF
I listed standard values here, so you should have no problem getting caps to match them in any local electronics store or online; the type of cap doesn’t really matter and will mostly be dominated by size, but I’ll share more about this in a minute.
Let’s quickly summarize the first installment of this column from last month’s issue: From a technical point of view, added capacitance shifts down the resonance frequency of the pickups, so they sound fatter, especially when using overdrive. This is exactly the reason why a lot of distortion and fuzz boxes with a vintage voicing use an additional cap at the input section; the resulting overdriven tone is fat and warm.
This month’s mod, which involves adding a capacitor to your signal, works best with vintage-flavored single-coil pickups (approximately 2.4 H inductance) or a typical old-school PAF-style pickup (approximately 3.8 H inductance). Modern high-output pickups are often sporting inductances of 6 H to 8 H, and don’t sound very good with this mod—when adding more cable capacitance to such pickups, the result is a dull and wooly tone without any clearness and definition. If you want to make your single-coil guitar sound more Les Paul-ish, you should try a 4.7n capacitor. It will shift the resonance frequency of your single-coil pickups down to the typical PAF ballpark, making for a very cool and usable old-fashioned guitar tone. It might feel a little muffled when playing clean, but ultra fat and punchy when using overdrive! In general, values higher than 4.7n are not recommended.
We have two options for where to install our cap.
On the Guitar Cable
This is the easiest location to add additional capacitance to your system, with several mod options:
1. The lightest mod ever isn’t a mod at all—it’s to simply buy a vintage guitar cable and plug it in whenever you need it! I don’t know of any company that offers modern guitar cables with intentionally high capacitance.
2. The Neutrik company offers a special angled plug, called the Timbre Plug, that you can solder to any guitar cable of your choice. The plug has a 4-way rotary knob on top to toggle between different capacitors. In addition to a bypass setting, the plug offers capacitances of 1nF, 2.2nF, and 3.3nF, letting you simulate different cable lengths on the fly.
3. You can add an additional capacitor to any guitar cable of your choice to convert it into a “longer-sounding” cable. You simply open one of the plugs to solder the cap between the hot and ground—that’s it. Small, 2.5 mm contact spacing ceramic caps are easy to put into a standard plug and are your weapon of choice here. It’s essential to only add the additional cap to one of the two plugs, but it doesn’t matter if you plug this side into your guitar, an effect, or your amp. This method allows you to build yourself some cables that simulate their older, longer relatives.
You can add an additional capacitor to any guitar cable of your choice to convert it into a “longer-sounding” cable.
Photo courtesy SINGLECOIL (https://singlecoil.com)
Inside the Guitar
You can also add a cap (or several) inside your guitar if you only need this mod for one instrument. If you’re looking for added capacitance with all your guitars, you’d be better off choosing one of the techniques mentioned above.
1. The easiest way is to solder your additional capacitor directly to your volume pot; this way it has a fixed value that can’t be changed and is always engaged. This operation is very simple to do, and you can use regular-sized caps for this.
You can add a cap (or several) inside your guitar if you only need this mod for one instrument.
Illustration courtesy SINGLECOIL (https://singlecoil.com)
2. If you want to make the cap switchable, such that you can run it either bypassed or engaged, you can install a SPST mini toggle switch or use half of a push-pull or push-push pot, which usually sport a DPDT switch underneath.
This drawing shows how to make your additional cap switchable.
Illustration courtesy SINGLECOIL (https://singlecoil.com)
3. If you want to use more than one cap to simulate different cable lengths, your weapon of choice is a rotary switch, setting up a kind of Gibson Varitone wiring without the inductor. Because we are switching capacitances, it is essential to run an additional 10 meg resistor in parallel to each of the caps, and to use a make-before-break, not a break-before-make, rotary switch to prevent loud popping noises when using the switch while your guitar is plugged into an amp. Leave the first lug of the rotary switch open for the bypass position without an additional cap.
If you want to use more than one cap to simulate different cable lengths, use a rotary switch.
Illustration courtesy SINGLECOIL (https://singlecoil.com)
4. If you want to make this mod even more flexible, you can add an additional “cable simulator pot” to your system. The pot should have the same resistance as your volume pot, and should be wired to your volume pot. This way, for example, you can add a 3.3nF or 4.7nF cap to the extra pot, and dial in as much cable capacitance as you like.
You can also add an additional “cable simulator pot” to your system.
Illustration courtesy SINGLECOIL (https://singlecoil.com)
On the Pedalboard
The idea of putting a rotary switch or cable-simulator-pot solution into an external unit to create a kind of extra-capacitance stompbox to use with all of your instruments is just around the corner, and yes, it’s possible! However, I don’t recommend this, because it’s physically located after the volume pot in the guitar, which means less volume (no unity gain) and less high end. But don’t worry: If you are looking for a pedalboard solution to simulate different cable lengths (which, as we defined earlier, means to shift the resonance frequency of the pickups), there are some active solutions on the market offering such a feature, usually in combination with a boost or buffer functionality. To name just a few, you should look into the Seymour Duncan Pickup Booster, Stellartone Micro Pedal, or the i2e Audio AG1.0 The PURR. Along with some other brands, these pedals will do the trick, and they’re not difficult to build if you are looking for a DIY solution.
So far, I’ve received several emails from readers asking for some more DIY guitar tools, so next month, we will look into some sustainable and environmentally friendly DIY guitar helpers—all of which you can build yourself easily by upcycling things you already have at home. Stay tuned!
Until then... keep on modding!
