Channel Islands Audio PEQ-1 MKII Phono Preamplifier

Long Time Comin’

Equipment report
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Channel Islands Audio PEQ-1 MkII
Channel Islands Audio PEQ-1 MKII Phono Preamplifier

Channel Islands Audio was founded in 1997, the brainchild of one Dustin “Dusty” Vawter and some friends. Dusty had expressed his fascination with music and all things electronic from an early age, and after completing his education he initially worked for a local home/car audio shop as a repair technician. His early career found him at various other audio companies where he took advantage of working side by side with many top engineers, learning all they would teach him.

By the time I first heard his name, in the mid-1990s, he had become the chief technician for the original and highly innovative company Audio Alchemy. That’s right, the same Audio Alchemy that was recently revived by Peter Madnick, and sold to Elac in November of 2016 in conjunction with Elac’s 90th anniversary. I first heard Channel Audio Islands-modified gear (Vawter was doing some devilishly good mods to Audio Alchemy DACs, power supplies, and reclocking devices) back in 1997, when I reviewed and subsequently purchased the Audio Alchemy DDE v3.0 upgrade and the Monolithic Sound Power Supply. I have owned a good number of CIAudio products over the years, and in fact, my reference Class D monoblock amplifiers are the Channel Islands Audio D-500 MK IIs.

The CIAudio PEQ-1 MKII is the result of a design envisioned almost four years ago, but continually put off as more pressing projects arose. When Dusty finally committed to working on it non-stop until it was complete, he had gone through a total of nine printed circuit board layouts before he decided he couldn’t make any further improvements. He confided to me that this is probably the best electronic design he has ever done.

Born in the USA
The PEQ-1 MKII is impressive right out of the box, before you have a chance to plug it in and give it a listen. It may be small, at just 8 ½" wide, 2 ¾" tall, and just 6 ½" deep, but it is robust, weighing in at some 8 pounds. The chassis is thick milled aluminum. The faceplate bears only the stylized CIAudio logo centered near the top, two widely spaced blue LEDs, one each to indicate left- and right-channel power, and the model number near the very bottom left corner.

The rear panel is divided roughly into thirds. The leftmost section houses the right-channel single-ended output and input jacks (high-quality gold-plated Cardas), and a horizontal slot allowing access to a row of seven DIP switches. The centermost section is identical, housing the left channel connections, and the rightmost third holds the chassis ground selector (AC or DC, depeding on whether you use the wall-wart DC supply, or an optional $299 external AC supply), a tonearm ground, and the IEC power input socket.

Before connecting the PEQ-1 MKII to your playback system, you will need to configure the DIP switches to match your phono cartridge and playback needs, and given this realistic price point, you get quite a decent number of options. That task is made super simple with the inclusion of a purpose-built DIP-switch adjustment tool. The first three switches in each row set resistive loading, selectable at 47k ohms (mm), 100k ohms, 470 ohms, or 1k ohms (mc). The fourth and fifth DIPs select capacitive loading options of 100pf, 270pf, and 370pf. Switch six sets gain (45dB and 60dB), with custom gain options available if needed (at a nominal fee), while DIP seven provides subsonic filtering, -3dB at 18Hz.

When the unit is plugged in (there is no power switch), power is fed to two independent (dual mono) filter/regulation circuits of identical layout, to ensure exacting performance from, and reduce crosstalk between, both channels. CIAudio claims this results in ultra-low noise on par with the best battery technologies, but without the inconvenience of batteries.

RIAA playback equalization is realized with a passive high-frequency cut followed by an active bass boost. As mentioned, the PCB layout went through nine revisions, the results of which yield the shortest possible signal path from input to output. The layout features a combination of star-grounding power-supply/ground plane components for the audio circuits to present the most silent backgrounds and reduce EMI/RFI pickup. The circuit board is housed in a heavy steel Faraday cage inside the aluminum chassis to further reject outside interference.

The circuit board is populated with only first-rate components, including Vishay 2% polypropylene signal and bypass capacitors, Nichicon Muse NP power-supply capacitors, Takman metal-film and carbon-films resistors, Grayhill switches, and the Cardas jacks. This is one sophisticated design, exceptionally well implemented, and exhibiting surprisingly high build-quality for a product selling for under $1000 that is built in the U.S.A. As if that weren’t enough, each PEQ-1 MKII comes with a five-year warranty.

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