Korby KAT

Should Korby's KAT be in your kit bag? We put it to the test...

Korby Audio Technologies are 'boutique' microphone manufacturers based in Nashville, USA. Their leading product is a modular mic with interchangeable capsules designed to mimic various classic and vintage mics, such as the Neumann U47 and 67, Telefunken 251, AKG C12 and Sony C800. A little lower on the price scale is the solid-state, fixed-capsule KAT FET model. This still has a 'hand tuned' capsule design, to maintain that sense of 'boutique character' but as it's a fixed-capsule mic with a simpler solid-state impedance converter, the price is slightly more affordable. The manufacturers claim that the FET (Field Effect Transistor) electronics provide a tighter bottom-end character, combined with an airy top end (in comparison to typical tube microphones), which is pretty much a true statement for all solid-state mics, in my experience.

First Impressions

The microphone ships in a strong, foam-lined plastic flightcase and is protected by a soft fabric bag. The polished-steel mic body measures roughly 160mm long by 40mm in diameter and is permanently supported within a large U-shaped bracket which can be fitted to a stand via a 5/8-inch threaded tube. A 3/8-inch adaptor was supplied with the review model. The bracket is over 175mm long and mounts just below the halfway point on the mic, with thumbscrews to allow the angle of the mic to be adjusted. The whole assembly is, therefore, actually quite large and imposing.

The mic's output is presented on an XLR at the bottom of the body in the usual way, and the serial number is provided on a screw-on label around the base. The top half of the body is milled to provide a protective grille, lined internally with a single layer of fine wire mesh, giving an attractive bronze-effect finish. The top cap of the mic unscrews to reveal a view of the edge of the large, one-inch diameter, centre-terminated capsule. The KAT is a side-address microphone, of course, and the front of the polar pattern is identified by the Korby logo on the mic body.

This is a fixed-pattern cardioid mic with a quoted frequency response of 30Hz-18KHz and a sensitivity of a reasonable 18mV/Pa. The published specs suggest this figure is A-weighted, which I assume is an error, and, rather than quote the self-noise, as all other manufacturers do, they quote a signal-to-noise ratio. The figure of 80dB ref 1Pa (A-weighted) translates to a self-noise figure of 14dBA, which is adequate for a large-diaphragm mic, but not impressive. The best are typically around 7dBA.

Continuing with the specs, the maximum SPL (for 0.5 percent THD) is a creditable 130dB, and the phantom power current consumption is a remarkably modest 0.4mA. No literature was supplied with the mic, and only the raw specs I've related above are given on the web site, which is rather disappointing for a mic that costs this much. Further, no polar diagram or frequency response plots are published at all, which is more disturbing — almost suggesting there's something to hide! In all, this mic has a reasonable set of specifications, but not state of the art, and there is little supportive evidence of the technical quality of the mic.

Listening

I tried the mic on my usual sources and found that the polar response is a fairly broad but even cardioid. Like most large-diaphragm cardioids, its pattern is wider at the lower-frequency end and tightens considerably with increasing frequency. The overall response is fairly bright — 'airy' seems almost too gentle a word for it.

When used with some female vocals on tracks that suited the style, it gave a lovely breathy quality, but on many others it sounded sibilant or scratchy, and I couldn't find a male vocalist that it really worked well with. Obviously, this is a subjective thing, and it's not an unusual problem with capacitor mics at all. However, it does highlight the fact that you can't even consider very expensive high-end mics as 'fit for all seasons' — there are just too many interacting variables that you need to consider when recording.

Korby recommend the KAT as a drum overhead, and I can certainly support that idea — it worked very well in that application on a small jazz kit, generating a bright, clear and natural track, with good clarity and a good balance between drums and cymbals. Headroom wasn't a problem at all, despite the lack of a pad switch. However, on most other sources (piano, electric and acoustic guitars and 'cello), I found it a little too bright for my tastes, although its character certainly helped things to cut through in dense mixes without needing fistfuls of EQ.

To me, this seems an expensive microphone given its performance and technical specifications, and its tonality doesn't appeal to me. But then neither does the tonality of the AKG C414 TLII — and an awful lot of people love that mic, so it is, as always, a case of horses for courses. The KAT is unusual in its styling, which will appeal to many, and there is nothing intrinsically 'wrong' with its performance, but I would suggest a definite need to try before you buy with this microphone.