Now it's time to test three microphone models from the American company Heil Sound Ltd. In all three cases the operating principle is dynamic; you know, moving coil, which means they don't need any kind of external power. Despite that operating principle, the behavior (the response they deliver) of these three mics is close to that of condenser microphones, especially in the case of the PR35 and even more so the PR40. These three HEIL designs also withstand high sound pressure (high SPL), which makes them ideal for a wide range of applications. COEL S.L.
The official import and distribution of HEIL mics in this country is handled by Consultores Electroacústicos S.L., a company from Biscay located in the Elizalde district, whom I'd also like to thank, while I'm at it, for the attention they gave my questions at the time.

It was 1998 when COEL S.L. began its activities in the field of professional audio and electroacoustic consulting. Today, in addition to HEIL SOUND products, they distribute a select range of one hundred percent cutting-edge brands, aimed mainly at electroacoustic installations and radio and TV studios. A couple of very telling examples of what I'm saying are their distribution of things as sophisticated as those made by LECTROSONIC or CLOCKAUDIO. To put it in plain terms, COEL is seriously serious.

The PR22
This is a microphone designed, in principle, for vocal use, and to that end it has low handling noise, something I certainly confirmed while testing it. Strictly speaking, HEIL presents it as a "Low handling noise vocal microphone." It is therefore meant to be handheld by singers or announcers live, although it can also be an excellent choice for recording.

Because of the high sound pressure level it can handle without flinching (without overloading), together with its pickup quality and articulation, the PR22 is also highly recommended for miking the snare in a drum kit and, as you probably know, you can place another one underneath (the latter in reverse polarity) to capture the snares, or to have better control over the possible coloration and/or definition of the drum in question. It is also well suited for wind instruments, guitar and piano.

The PR22 comes in a carrying bag with a handle, which also includes a mic clip, a pair of interchangeable heads (one silver and one gold, in addition to the black one mounted on it) and a foam windscreen.

The PR 35
The PR35 model is something a little more special. This microphone has much the same possible uses as the PR22 above, though with some differences; mainly because, on the one hand, its frequency response is wider, and on the other, it includes a second coil that cancels induced noise (hum bucking coil), which makes it suitable, for example, for use near video monitors without the magnetic field they generate affecting it or inducing noise through electromagnetic field (EMF) interference that might invade the environment where it's used. For that reason alone, it is highly recommended for use near electronic equipment, as is normally the case in radio and TV studios.

Its sensitivity is also somewhat higher than the PR22's and, like it, it offers a wide dynamic range. On its body we find a three-position switch to engage its built-in filter network (low-cut filter), which is always welcome. In the first position, the PR35's frequency response remains unaltered (flat), while the next two engage bass attenuation in steps of about -3 dB each.

An aluminum carrying case (a mini briefcase), which includes a very good-quality clip, is the ideal container in which HEIL presents this mic.

The superb PR40
The microphone I have left to discuss doesn't have much in common with the previous ones. Right off the bat, it turns out to be a full-range mic with ultra-extended pickup in the lowest part of the audible spectrum: the PR40 can capture frequencies or tones from around 28 Hz, something truly unusual for a dynamic microphone. On the other hand, this is not a handheld mic, and what's more, it is a so-called large-diaphragm microphone.

Given the above, the PR40's real specialty is as a kick drum microphone and, in general, for instruments whose range extends into the deep lows. Its body is made of zinc, it has double acoustic shielding to prevent pops, and its diaphragm is made of aluminum.

Because of its design and construction, the PR40's capsule has a magnetic field ten times stronger than that of a traditional dynamic mic. As with the PR35, a second coil that cancels noise from induced electromagnetic fields is also present in this microphone's capsule.

I can assure you that this HEIL SOUND design is something sublime, something that, if you get the chance, you should at least try. I'd say this PR40 raises the bar for dynamic mics designed mainly for the primary function mentioned above to a new level. With such a wide frequency response and, of course, great dynamic headroom, we also find that, of the three mics under test, it is, as you'd expect, the most versatile of all.

HEIL presents the PR40 in an aluminum case that also includes an adjustable SM-3 mount (very professional), instead of a clip as in the previous cases.

With some regret
Sadly, I now have to think about repacking and returning my three new little friends, born in Chicago, Illinois (that's where HEIL SOUND designs and builds them).

I tested them with my own voice, recorded digitally using my EDIROL UA 25 (at 48/32, although that sample rate and resolution are a bit over the top for a vocal take), and then played it back to make sure my own hearing interference had no influence (because when someone speaks or sings they are in a natural state of transmission/reception, and so what they actually hear is a mix of their own voice through the air + internally + through bone, adding in that case the airborne and also bone-conducted sound from the amplification system or headphones. I've just told you why, believe it or not, it's a bad idea to EQ or adjust your own voice yourself: something may seem one way to you when in fact it's another). I find that the PR22 and the PR35 perform very respectably; in both, the clarity (and therefore the intelligibility) of the message was quite evident, although the PR35 wins on points, since it also gives the voice extraordinary body, so much so that, in my opinion, if a singer used this mic on stage it would be almost mandatory to engage at least the first bass cut (-3 dB); whereas for announcers and/or presenters it would be wonderful, since they routinely use that effect on their voices. They should try it, because it really stands out. Compared with the PR 22, the PR35's output level is immediately noticeably higher.

As for the PR40, I also initially tested it in the same way as the others and it worked perfectly well. Because of its range, the widest frequency response of the three, it strikes me as the most versatile in the comparison, which makes it an especially valid option for recording studios. As you'd expect from a mic designed mainly for kick drum, it performed ideally on the bass amp, which was ultimately the acid test I put it through. As a result, it comes highly recommended for that job; and of course, for kick drums, floor toms, double basses and, generally speaking, instruments with low registers, I get the impression that few mics are in its league.

To finish, I should mention that throughout all the tests I carried out with these three magnificent mics, as you'd expect, I prudently used no EQ or gadgets of any kind, in order to preserve as much reality as possible. I even did most of the listening on headphones connected directly to the EDIROL (my large-diaphragm AKGs) to rule out and/or discern the influence of the listening room (which is rather shabby, I'll admit). Otherwise, all the impressions described would automatically be invalid.

Despite the time I spent testing these microphones (I wanted to be as clear as possible and tell you all this as accurately as I could), I sincerely believe the occasion deserved it. This time, then, we're fortunate to have the folks at COEL. Until next time, friends.