In the late ’70s, Colorsound briefly produced an envelope-controlled formant filter called the Dipthonizer. The effect’s vocal-sounding vowels and diphthongs provide an animated sonic conversation with hints of phasing, wah, and talk box interplay. Originals are rare, so pedal pushers have produced clones of the endangered effect. One such gadget is TWA’s Little Dipper 2.0 with an analog circuit and some new additions, including a bass boost and expression-pedal support.

Across the Galaxy
Like the first-generation Little Dipper, the 2.0 version has a sparkly, midnight-blue finish. When you connect the 9V adapter (there’s no battery option), a constellation of LEDs lights up. Input and output jacks are on the right-hand side of the box, with the expression-pedal input and power adaptor on the left.

The occultation rotary switch, the newest feature on the Little Dipper 2.0, provides seven timing and EQ variations.

Like the original Dipthonizer, the Little Dipper includes built-in fuzz, here called diffraction. With the control counterclockwise, tones are clean. Advancing the knob excites certain frequencies, though the tone never gets really hairy. Ascension controls the filter’s sweep range, while the 5-way inclination switch sets the trigger timing for the dual filters.

The occultation rotary switch, the newest feature on the Little Dipper 2.0, provides seven timing and EQ variations, including high- and low-filter cuts, boosts, and delayed response. Additional controls include a +6 dB bass boost and three internal trimpots to fine-tune output level, dry/wet mix, and noise gate release.


Large variety of filters and great vocal emulation.

Some controls are hard to access.


Ease of Use:




TWA LD-02 Little Dipper 2.0

The Stars Align
Grateful Dead fans will be pleased to encounter many colors reminiscent of Jerry’s Mu-Tron-based tones. For example, I replicated the sliding funk rhythm of “Fire on the Mountain” with the inclination switch in its fourth position and ascension in the 3 o’clock range. Jerry’s tone is fairly clean, so leaving the diffraction rolled down is a must.

Still in fourth position, I increased diffraction to a hint above noon for emotively babbling single notes reminiscent of a talk box. Of course, you can’t replicate the exact expression of Peter Frampton’s crooning, but it’s in the ballpark. Some higher diffraction settings make inclination a bit muffled, and that’s where occultation helps out.

With a Tele and a Fender Bassman, I enjoyed the cocked-wah sound of the second position, but needed a bit more presence for lead play. The occultation control let me add enough midrange to edge my notes above the mix. Unfortunately, this slot-headed mini-pot requires a flathead screwdriver—a pain to deal with onstage.

The bass-boost switch is great should you want to use the Little Dipper on bass guitar, since some of the formant filters tend to suck low end. Flipping this switch adds 6 dB at 80 Hz. There—you’re all set for that Geezer Butler solo.

The Verdict
TWA adds some great features to their latest Little Dipper, making it a very versatile envelope filter. However, some controls are difficult to access live, including internal ones such as wet/dry mix, and frequency EQ/delay, which requires a screwdriver. The $299 price tag is a bit steep, but vintage Dipthonizers aren’t exactly cheap. The Little Dipper 2.0 covers a lot of ground with its great tones and unique design.