My Own Small Diaphragm Condenser Shootout

This will document my own personal process buying a small condenser Mic.

I had used many of these in big studios producing bands, but could not afford good ones for myself – and I have so many large diaphragm condensers, I was not sure I needed a killer small diaphragm condenser. Boy was I wrong. I knew I liked km84’s.

First, I bought a pair of Octavas. They sounded pretty good. I used them for overheads. I had the multi capsule set, and that was handy.

Then one day I borrowed a set of KM184’s to do some violin tracks. I did an xy pair, and it sounded so great - creamy yet dripping with great tone, accuracy, and realism. I realized what I had been missing. The symphony violin player told me it was the best she ever sounded on tape. I was jazzed.

It seems every major mic manufacturer makes a line of small diaphragm condensers. They come with different patterns, and features, but usually its all one capsule packaged differently.

The first thing I learned was with a cardioid mic, the off axis coloration is the difference between the men and the boys. The class mics sound the same on and off axis – which turns out to be very important unless you record in an anechoic chamber. In a lot of cases its worth using omni and taking the room, just to avoid the coloration of cardioid.

The next thing I learned was that the really great small condensers, like the large, are expensive. Schoeps, B&K (now DPA) – these are the standards of excellence.

The third important thing is proximity effect. The earthworks cardioids are great – but only flat in the low end 6 inches from the source. Other mics are flat further from the source but too sensitive in the low end. Compromise mics are just that. You really need to buy a purpose-built mic.

Other qualities I was looking for were quiet, and “realism”. Does a thing sound like that thing. Too many mics have a high end boost too – I wanted neutral.

Testing . I actually tested 4 cardioid mics in the following manner. I hung them over a drumset, together, at identical heights, several inches apart, and recorded drum hits. The mics I tested were the km184 (@$700), the Rode NT3 (@$300 for two), the studio projects C4 (@ $350 for two), and the Octava (@$200 for two). I could then bounce between tracks to AB any with any other. I also recorded a bunch of room tone. I used my RME quadmic preamp – which I think is very flat, fast, and transparent for all the mics. They went into my aw4416 analog inputs at 24 bit via rme preamps.

Here’s what happened.

On the toms, the mics sounded a lot alike. The KM184 had more low end – almost too much. All the others sounded similar. Octava a little scooped. On the high hat, the Octava was clearly harsh compared to the others - nasty. On the snare, the km184 sounded like a snare – but they all sounded good. On the kick the km184 had too much low end. On the ride they each had their own thing – but none was bad. Every time, the km184 sounded a lot like what we were recording. The studio projects did too – and with less hissy stuff. It was just deadpan a reflection of what was happening. The room tone test was the most revealing. The km184 sounded colored hissy, or even boxy. The Octava was noisy. The Rode had this very strange low midrange peak, and a hissy peak. Odd. The Studio projects just sounded like the room. I went into this test ready to buy the km184 (and they do sound beautiful) – but, trusting my ears, I went with the studio projects. They may (may!) lack a tad of detail – hard to tell – compared to the km184 – … I could be confusing that with the “air” built into the km184’s curve. If you want a mic that sounds great, keeps up with the km184 on performance in the midrange, and has no hidden strange stuff, the c4’s are a good bet - and to my ear, no compromise, and better than the km184 for things where neutral is important. The fact that they are way less money is nice. Bottom line, you get what you pay for, more or less, but the c4 is a heck of a deal. The old km84 is like the km184 but without the high end boost. Thus, without a km84 to test, and since the c4 is like the km184 but without a high end boost (and a little less low end, which is ok with me) the c4 seems like the closest thing to the km84 – which is what I was shooting for.

This is consistent with several of the small diaphragm comparisons I’ve seen on the web. If price was no object I would have bought an earthworks sr77 for close up work and a pair of 4000 series dpa mics for everything else – without even testing them, simply because on balance the most credible sources and indications on the web are very clear about the quality and sound of these no-compromise mics. I’ve since used the c4’s on several tracks in commercial work and they were great. Quiet, balanced, neutral. Ted.

Footnote after using the c4 for 6 months and buying some a pair of Earthworks z30x’s as well. The c4’s with the right placement and the omni capsule turn out world class tracks. Big fat lively clean rich. The cardioid capsule is good too – but there’s a definite lack of openness. The z30x’s are as advertised (or reviewed).

They are amazingly accurate, sound like whatever they are micing – but you have to be careful of two things. The proximity effect is significant – you really want to hit that 6 inch mark if you want the flat sound. Also, they need a pop filter if there is anything remotely in the vicinity that will make “wind”. I swear they will pop if anyone in the room breaths too hard. OK, not that severe – but beware. I really screwed up a guitar track where the guitar player’s vocal pops (and this was the guitar mic) made it happen. As with any really flat mic, it will not flatter the sound. It better be a nice sound or the z’s will reveal the bad parts.