Lately, I've been working on a project tentatively called The Greatest Small-Diaphragm Mic Shootout of All Time, so I've been testing a veritable truckload of SD mics-Neumann, Gefell, Schoeps, RØDE, Studio Projects, MXL, and everything in between. Naturally, I wanted to get an MK-012 (Tape Op #25) into the mix, so I gave OktavaMod owner Michael Joly a call to see if he'd send me one of his mods to use in the project. As it turns out, he had already worked on an MK-012 for a friend of mine in Austin, so I was able to borrow his mic for the test. Still, Joly had something new he thought I should hear-a modification of the MXL 603 (Tape Op #28) pencil mic. Yeah, right, I thought.

"Sure, great," I said. He told me he'd send a Neumann KM 184 along with the MXL mod so I could compare the two, since he thought the two sounded similar. Score! I had managed to forget about the KM 184 in my SD shootout plans, so I could definitely use a sample of that mic. And if the MXL mod really did sound as good as a KM 184-a much maligned mic in my opinion (and I've got the sound files to prove it)-then maybe I'd include it in my small-diaphragm mic project as well.

The chain I use for mic testing is as follows: the mic is plugged into a 15 ft Monster Cable Studio Pro 1000 mic cable, fed to a Millennia Media HV-3B preamp, then to Lavry converters, and finally to Pro Tools via a Digi 002. For each test, I play the same 30-second riff on a Collings C-10 acoustic guitar using a medium pick and recording in the same room. When the Joly mics arrived, I set up the KM 184 first, and as I strummed the guitar I heard an old familiar sound in my headphones. For years I had used KM 184s before I switched to vintage KM 84s, and while I do prefer that certain mojo you get from coupled transformers, both mics can do a great job on acoustic guitar. Since I had just heard a test Joly had done on Gearslutz that compared the KM 184 and his MXL mod (officially called the Ultimate MXL 603 Mod), I stole some of his methodology and jangled my car keys in front of the mic. Then I grabbed a shaker and shook it like an English nanny holding a baby-percussion test completed.

Truth is, I really only use small-diaphragm mics for one thing-recording acoustic guitars. I don't use them to record classical concerts or drum overheads-just acoustic guitars, mandolins, standup bass, and the occasional guitar amp. I guess I would record a shaker if someone asked, but I prefer to use sound files instead. Also, my acoustic guitar tests tend to use more of a Gestalt approach, so rather than measure the distance scientifically and record from the same distance each time, I mic the guitar where it sounds best overall. That's what I'd do in a session, so that's what I do for a test. For most mics, that's somewhere around the 12th or 15th fret and about 8-10'' away.

When I finished the tests on the KM 184, I switched out mics and tried the same three tests with the MXL mod, starting with acoustic guitar, then car keys, then shaker. It really did sound a lot like the Neumann. In fact, after re-listening to the sound files in preparation for this review, I think the mod sounds a little bit better than the KM 184, especially on acoustic guitar. The high end is sweet, clear and present, but never brittle-just what you would expect from a high-dollar transformerless mic such as, for example, a Schoeps. There's a solid low end that doesn't turn into mush like it does in the original MXL 603s (yes, I had some stock MXL 603 sound files handy for comparison), and it doesn't get overbearingly boomy either. While the low end in the MXL mod is very similar to the KM 184, I prefer the highs in Joly's mic overall. Oddly, in Joly's "scientific" test online, I thought the KM 184 sounded a tad better than the MXL mod, the opposite of my results. As to the car key and the shaker tests, the results were inconclusive. I prefer to use a large-diaphragm mic when recording car keys anyway, and a spaz on a shaker is just a spaz on a shaker, regardless of mic quality.

So how does Joly turn water into wine exactly? Besides modifying the electronics, he also modifies the capsule and the vents just underneath the capsule. Joly describes his process in more detail at his website, but here's the bottom line: you can buy a brand new pair of MXL 603s online for $199, less if you buy used. Then you can buy the Ultimate MXL 603 Mod for $199 per mic and have a pair of SD mics that are sonic siblings to the much more expensive Neumann KM 184 for about $600. If that's still too expensive, you can opt for the economy model and get the MXL 603 Premium Electronics Mod for $89. While I didn't get a chance to test it myself, Joly promises that the harsh high end, phasey mids, and overall graininess of the mic will be vastly improved. This mod also works on the CAD GLX120 and the Nady CM 90.

But wait, there's more! I nearly dropped the phone when Joly told me about the other modified mic he was going to send along with the Neumann and the MXL-the lowly MCA SP1. You remember the MCA SP1 (Tape Op #60), the now- defunct Mr. Mic-looking contraption that came in the same clear plastic packaging usually reserved for common household items such as flashlights and chicken knives, don't you? Well, there's a hidden '84 in that mic, Joly says. Same thing goes for the Nady SCM 800, MXL 990, and the MXL 770. Wait a minute? Aren't these large-diaphragm mics? Nope. According to Joly, the capsules inside these mics are actually small-diaphragms doing their best to ape a KM 84, so he came up with the $189 Hidden '84 Mod to get the most from these oddly-designed mics.

Years ago, I bought a $59 SP1 on a whim and found it absolutely unusable, so I gave it to a friend just starting out in home recording. It sounded nothing like the Joly-modified SP1 I had recently put in front of my Collings, and I was amazed by the sound, especially the rich midrange. Did it sound as good as a KM 84? No, not really. Did it sound as good as the MXL mod? No, not at all, but it sounded way better than I ever thought an SP1 ever would. True, I wouldn't recommend that you go out and buy an SP1 just so you can have it modified, but I'm sure a lot of us got stuck with one, two, or a half dozen of these mics over the years, and if you still have them, you might want to salvage your initial outlay by having Joly reinvent them. Like I said, I wouldn't rush out to buy an SP1, but I plan to call up the friend I gave mine to and tell him about the upgrade possibility. Joly also recently started offering a $69 Hidden '84 Capsule Upgrade option to this mod that he claims reduces coloration due to refraction and resonance from a flaw in the capsule design.

So will I buy these upgrades myself? Frankly, I don't know. The mics I'm using these days are big league models- Schoeps, Gefell, Neumann. I wouldn't expect something like an MXL mod to compete with those brands, but the truth is, it gets damn close, and it's a financially-friendly way to get better sound now. With the economy in the shape it's in, and no relief in sight, I might have to buy them eventually anyway, and probably sooner than later.

Tape Op is a bi-monthly magazine devoted to the art of record making.

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