Surf Nicaragua Vibes'n Verbs vibrato + analog spring reverberator
Watch this: https://youtu.be/J1LqeLIKXbs?si=Szvw5t1QBmjsIx8S
Or skip the YouTube video for a lot of reading instead...
This is a design I've been tweaking and fiddling with for a while, and I finally think that it sounds like something to be proud of. But first things first:
Power requirements:
This unit does not work with battery power. A standard boss or one-spot style, 2.1mm barrel, negative center supply is what is required. The pedal needs at least 30 milliamps of current to function (most wall-wart plugs deliver at least 100 mA, so no worries there). Once the power makes it past the on/off stomp switch, it hits a 12 volt DC charge pump that powers the vibrato, the reverb, and the tone+master volume stage.
Credit where it is due:
1. the switch is based on the Demedash Incandenza - a super simple, super reliable relay design that uses a 555 timer and the same high-quality soft-touch footswitch that goes in much more expensive pedals (from manufacturers like Strymon).
2. The vibrato is a single-stage optical modulator that uses an LED and a light-sensing resistor to make the sound wobble. It is based on the design found in vintage Magnatone amplifiers.
3. The reverb is a highly-modified version of an older, out-of-production kit that Björn Juhl (Mad Professor, BJFE, One Control) came up with and sold through Moody Sounds. It uses an Accutronics AMC2BF3 long decay spring tank that has just under three seconds of max decay time.
4. The tone control is essentially the values from the Ram's Head Big Muff distortion, with flat instead of the characteristic scooped-mid tone profile. The master volume is quite similar to the vintage LPB-1 linear power booster circuit - which is an extremely common recovery stage that gets used in tandem with the BMP tone control.
The controls, from right to left, are as follows:
1. the vibrato can be dialed in to control depth and speed, and the indicator LED will dim or brighten, as well as flash with the rate of it. The three position toggle changes both the minimum and maximum range of the speed/rate. To dial out the vibrato completely, set the knobs at fully counterclockwise and keep the toggle at the slowest position.
2. At fully counterclockwise, the tone control will boost bass and cut treble. It is flat in the middle and will cut bass and boost treble when fully clockwise. The toggle just above the tone control will bypass the tone pot when in the "up" position and makes the whole circuit louder and fuzzier.
3. The dwell knob acts like a feedback level control and determines how much signal gets sent to the springs. Turning it up will also saturate the signal with additional gain. The mix knob controls the dry/effect mix of the through signal vs. reverbed signal.
The yellow and black "caution" tape is meant to be a target for striking in order to get the "crashing" sound you get when you jostle a spring tank. I include this with a warning that too much pounding may eventually snap where the springs connect to the transducers inside the tank. HOWEVER - the tank is replaceable and the wires attach with quick connectors - so a repair is possible if this ever happens. I would not, however, attempt this yourself - I will, of course be happy to offer this for the cost of a replacement tank (currently, about $9) plus the cost of shipping the unit back to me.
Other build notes:
The circuits are hand made and assembled on busboard epoxy-glass stock that I cut individually for each build. All potentiometers are a mix of gorva, alpha, and TT electronics. The 1/4" jacks are high quality Lumberg plugs - and everything is wired, by hand, offboard. Consequently, there is a lot of wire inside each pedal. This is how I build, and welcome any and all accusations of resemblance to "a rat's nest"...
This unit can sound like a traditional, subtle-but-watery vibrato. Or a delicate, warm, rich spring reverb. But it can also sound like a crashing wall of sound at the end of the world, and I hope that anyone who uses it can appreciate it for these qualities.
Also, for those who care, the name "Surf Nicaragua" was originally taken from a T-shirt that Val Kilmer is wearing in the movie "Real Genius" but I have since learned that it is ALSO the title of a Sacred Reich tune about American Imperialist aggression in Central and South America. So I'm okay with BOTH references.
Thanks!
-Chris, CDCE