Pickups 101

What is phase and what does a phase switch do?

Phase switches are usually marketed as a feedback-controlling device, but they accomplish more than just that. Phase determines at what point in time a sound wave has its peak or trough.

This picture shows two (basically identical) sound waves (sine waves, to be exact), but the wave on the right (2) is inverted in respect to the wave on the left (1). Interestingly, if these two waves were played back simultaneously from the same speaker with the same volume, they would completely cancel each other out and no sound would be heard. There would be silence.

Out of phase guitar sound reproduction also suffers, to a degree, from phase cancellations. Amplification systems, effect units, or any electronic audio device may or may not invert the phase in of the signal coming in. In most cases the manufacturers do not specify.

Every acoustic instrument projects sound waves in a certain phase when it is played unplugged. The phase that is projected from the amplified speaker source needs to be “in phase” with the acoustic instrument’s own sound waves or the result will not be optimal.

If the instrument’s natural and amplified sound waves are out of phase, the result is early feedback and tinny, unbalanced sound, which may be tolerable in some tone ranges (positions on the fret board) and quite noticeable in others, even resulting in sound cancellations on some notes.

The phase switch allows for instant correction of this problem. When you toggle a phase switch back and forth, you will notice fuller, warmer and nicely balanced tone with less feedback in one setting.

Trinity Pro Preamp

About the Trinity Pro Preamp

What’s different about the Trinity Pro?

The Trinity Pro Preamp is now a part of our Trinity Pro System, which is a huge step up in the sound quality and performance of our Trinity Systems! The secret is an integrated phase switch on the mic channel, which ensures that the microphone is in phase with the pickup, no matter the mic position or guitar model.

You know when an amplified signal just doesn’t “sound right”? In a dual-source system, chances are it’s a phase-match problem when the sound waves coming from one source are partially canceling out the waves coming from another source.

In pickup/mic combination systems, it’s actually a very common problem that the mic is out of phase with the pickup. The phase switch allows you to simply “flip” the sound waves of the mic so that they match the pickup. The result is that “aaaaahh” smooth tone that just sounds right.

Trinity Pro Preamp Features

The Trinity Pro Preamp allows for perfect balancing of a microphone and a pickup/transducer. Channel 2 is a designated mic channel with phase switch and supplies 9-volts to a lavalier type microphone. Each individual channel features volume, gain, +/- 20 dB bass, midrange, and treble filters. The EQ is accessible inside the box with trimpots. A convenient belt clip is included with this compact preamp, which weighs a mere ten ounces with the battery installed.

The Trinity Pro Preamp is built with K&K's "Silent-Filter-Technology" using only full-size components. We use full size capacitors and transistors because we think that they sound better than the miniature components in most of today's guitar preamps.

Aside from its strong bass, midrange, and treble filters (for each channel), it offers internal gain adjustments which set the pre-amplification factor from 1 to 10 (per channel). This means you can boost the input signal up to the 10-fold amount. It features two volume controls knobs on the outside of the box, one 1/4" stereo input (tip-pickup, ring-mic), a line level 1/4" mix output, and an optional 1/4" mic output that allows for splitting the two outputs for individual processing. Inside the box are adjustable controls for gain, bass, midrange and treble for each channel. The tone controls offer an incredible +/- 20 dB. This is a wider range than some big boards on the market today!

To keep the box as small as possible these controls are trim pots (small potentiometers that can be adjusted with the supplied precision screw driver). Once you've installed both pickups, you should adjust the trim pots to your personal taste and needs. During performance, the two volume knobs on the outside allow for fast balancing on the fly.

The Trinity Pro Preamp has a Main/Mix Out which carries both channels (mixed), plus the option of individual channel ouputs if a second cable is inserted in the center output.

Technical Specs

Frequency range 10 - 30,000 Hz
Input Impedance: 1 Mega Ohm pickup -500K mic
Output Impedance: 3 K Ohm
Average Current: 4.5 mA
Battery hours: about 50
Dimensions: 110 x 85 x 38 mm / 4+3/8" x 3+3/8 x 1+ 1/2"
Input and Output Jacks: 1/4" instrument jacks
Phase switch on the mic channel
Bass, mid, treble EQ, gain and volume controls per channel

Trinity Pro Preamp $227

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