A Three-Microphone Setup for Recording Classical Guitar
An M/S Stereo alternative.
Classical Guitar is a complex and rich sounding instrument; as such, it sounds better when is recorded with at least two microphones. A statement that you must have read several times already if you hang out at this site. Some engineers argue though that guitar is a relatively small instrument which tends to sound too "wide" when recorded with the most conventional stereo techniques; thus sounding unrealistic in playback.
Neumann TLM 193 and TLM 170 in M/S Stereo Configuration
Mid/Side stereo, which I discuss in my Three M/S Stereo Setups for the Classical Guitar article, is usually praised for its truthful representation of the classical guitar. The elimination of phasing problems and the flexibility it offers during mixing are additional important advantages, however, it is not immune to potential issues. Namely, the collapse of the room information in mono reproduction, and the inability to hear the resulted-combined sound without some processing to the channels (or the use of an M/S matrix). Lastly, symmetrical Figure-8 microphones, required for the "Side" channels, with a balanced response are generally expensive.
Alternatively, the combination of a "Mono" microphone placed at close-proximity and a "Stereo Pair" at some distance, shares some similar advantages without the drawbacks of M/S Stereo. Hence the Three-Microphone Setup is an appropriate option for capturing the subtleties of the classical guitar.
Purpose in position
Austrian Audio OC18 - A Large Diaphragm Cardioid Condenser
The "Mono" microphone is positioned close to the instrument (at about 50cm, although some could go as close as 30cm) to capture a full-bodied sound. I recommend a large-diaphragm condenser with a smooth treble response for this position; as not only it will capture the fullest sound, but the slower transient response of the large capsule will also give a less analytic, more relaxed response.
The "Stereo Pair" is placed a little further away to capture the sound of the room. A pair of small-diaphragm condensers is ideal here due to the better off-axis response and can be either Omni or Cardioid patterns depending on the acoustics. The actual distance depends mainly on the room; accordingly, as the distance increases, the height of the microphones should be increased as well. The distant pair brings to the mix crucial depth, space and some high-end articulation.
Decisions; Player vs Audience
Another way to see the three-microphone setup is as a fine compromise between the intimacy of what the player hears and the somewhat distant experience of an audience member.
During mixing, the three channels can be balanced to the desired sound; from close to distant and everything in between. Either the "mono" or the "stereo pair" can be used as the base sound. Think about a mono capture with some extra space or a distant pair with added fulness.
Examples
For the first recording, I used a Neumann TLM 193 relatively close to the guitar, and a wide pair of DPA 4011As as room microphones.
In isolation, neither the Mono signal nor the AB pair sounds particularly great. The first is somewhat plain and too direct, while body and weight are missing from the AB pair. When mixing all three microphones, the combined sound gets defined and three-dimensional; thus more real.
I made another example of the same setup and the exact same distances, this time with an Austrian Audio OC818 in Cardioid for the Mono duties. The AB pair is still the DPA 4011A. If you have read my Austrian Audio OC818 review, you already know that I love their sound, and I wanted to hear how well they can mix with the DPA microphones.
Combining M/S and Room Microphones
A few months ago, I also experimented with combining an M/S pair of Neumann TLM 193 and AEA N8 up close and a stereo pair of Austrian Audio OC818s at some distance, you can hear the result in this recording of Bach's Cello Prelude no.2.
Some things to take care of
If you want to try the Three-microphone setup, it is important to listen to the recording as a whole before committing to any microphone position. The Mono microphone may be judged alone if you plan to use for the main sound, but don't make bold decisions without listening to the combined audio.
Potential phasing nightmares is one of the biggest drawbacks of this setup, so take extra care to eliminate any issue and check with a proper phase meter plugin regularly (read my article on the Three Most Essential Plugins for Classical Guitar).
Lastly, although the recording should be evaluated as a whole, the close and distant setups might need to be EQed separately. Nevertheless, you may apply a catholic EQ with basic filters and sculpturing.
Cheaper Alternatives
Line Audio CM3 - A budget SDC with an surprisingly good sound
Apart from the aforementioned combinations, any microphone could do a decent job. If you just starting and your budget is limited, buy the best large-diaphragm condenser you can afford and a pair of cheaper small-diaphragm condensers, like the Line Audio CM3/CM4 (read my comparison of the Line Audio CM3 and DPA 4011A).
Final thoughts
I've seen mostly AB, XY, ORTF and sometimes M/S setups explored by engineers and home recordists for the classical guitar. All of which can produce excellent recordings given the right circumstances. Yet, I find that with more elaborate techniques I can capture the instrument, at home or on location, with exceptional precision, without any disadvantages. Except maybe for needing more input channels, cables, stands, and more time for the setup.
A Three-Microphone setup can shine in a very wet hall, as it allows us to capture the body and definition of the instrument while including as much ambience as desired. In a home recording of the classical guitar, it offers great flexibility, if not to provide ambience, it combines the intimacy and fullness of a close pick-up with some extra depth provided by the spaced pair.
So, what do you think? Have you tried a three-microphone setup? Which microphones have you used?
DPA 4011A vs Line Audio CM3
Line Audio is a relatively unknown Sweedish company, or rather a one-man shop, dedicated to manufacturing high-quality, unhyped microphones and linear pre-amplifiers. They have been in this business for more than 30 years, and by cutting the middle man, no advertising and minimizing cost on all the not essential elements, they offer their products at the most affordable prices.
DPA’s premium case.
DPA, on the other hand, is one of the leading names in the classical recording world. Many recording engineers, producers and musicians sing praises for their clarity and honest presentation. The microphones, as well as the accessories that accompany them, are as premium as it gets. But, performance comes at a cost.
In this duel, I wanted to see if the CM3 cardioid condenser stands any chance against the 4011A at a less than a tenth of its price. In other words, could someone with a limited budget still manage to get a decent recording?
Setting Up
I positioned the microphones at a small AB setup with 36cm between each microphone, at 96cm high and 55cm distance from the top of the guitar. At this distance, the microphones can capture the true sound of the guitar, and with their cardioid pattern, reject most of the room acoustics.
DPA 4011A Frequency Response and Polar Pattern
Line Audio CM3 Frequency Response and Polar Pattern
The details matter
Listening to the recordings, the DPA microphones have breathtaking clarity and detail at every frequency. They demonstrate a better resolution and capture a holographic image of the classical guitar, with more realism and depth. The 4011A are brutally honest microphones, but if you are recording a luthier grade guitar and a great guitar player in a beautiful sounding room, you want it all on tape.
The CM3s surprisingly (or not, if like me you have used them for a while) sound very close to the DPA. They are a little more plain sounding, with less resolution and depth, in comparison it feels feel like something is missing from the image. They are also less sensitive and can benefit a lot from a good preamp, but peculiarly they were only slightly noisier than the 4011A in these recordings.
Line Audio’s basic but very portable case.
A distinct approach
The Line Audio CM3s come at a very minimal package, shipped in a simple plastic box, with a basic plastic microphone holder and a decent windscreen. They are so inexpensive, so there is nothing to complain there really. They are also light and small enough, almost as small as an XLR adaptor, that I'm not hesitant to carry a pair even my jacket's pockets.
DPA sent me for test their premium stereo set, that comes with a luxury case and all the accessories you might ever need. The craftsmanship is impressive, everything feels finely processed with all the pieces machined out of solid aluminium. The full assembly looks stunning. Their stereo bar, while relatively expensive, is the best I've ever used.
DPA 4011A Stereo Set, all the accessories you’ll ever need.
Single 4011A or a more basic stereo set up is available, they come with only the essential accessories in a hardshell nylon case. This case is also of premium quality and judging by my experience with the d:vote 4099g (you can read my review here), I prefer this kind of case to wooden cases that come with most higher-priced microphones. As you cannot carry them easily for location recording because of weight and size. This is true especially for small-diaphragm condensers, which might see more commute than larger studio microphones.
For different use cases
In conclusion, the 4011A is the better microphone of the two in every aspect. Taking us a step closer to capturing the classical guitar in all it's nuance. Also, if you charge for your recording services, showing up with the DPA set will reassure your clients for the extent of quality you are committed to.
If you are on a limited budget, or just want to record yourself for non-commercial uses, the Line Audio microphones are the best-kept secret of the recording world. The CM3s can capture classical guitar with realism and honesty and are so inexpensive, you can buy a few.
In conclusion, the 4011A is the better microphone of the two in every aspect. The engineering and the accessories are unparalleled in quality, not to mention the sheer detail and sound quality that they capture. Taking us a step closer to capturing the classical guitar in all it's nuance. Also, if you charge for your recording services, showing up with the DPA set will reassure your clients for the extent of quality you are committed to.
But, if you are on a limited budget, or just want to record yourself for non-commercial uses, don't shy away from the Line Audio microphones, as in my experience it is hard to find any other small-diaphragm condenser microphone with such natural characteristics at this price range or even many times more expensive. The CM3s can capture classical guitar with realism and honesty and are so inexpensive, you can buy a few.
Line Audio CM3 on a Classical Guitar
The Swedish Line Audio CM3 microphones are the best-kept secret of the audio world, not only they sound great capturing the nuance and timbre of acoustic sources in the most natural way, but they are incredibly cheap and small!
No affiliation whatsoever, I just like them a lot!
Initial Review
Roger is the one and only person involved in the design and manufacturing of the Line Audio products, and he has been making high-quality microphones and preamps at a low price for decades; all handcrafted in Sweeden.
It is impossible to find other microphones that come close to the quality of the CM3s, both in craftsmanship and sound properties, without spending several €100s more. They are balanced across all frequencies and offer a smooth and clear pick-up, without annoying frequency boosts that certainly don't compliment a sensitive and delicate instrument such as the classical guitar.
Roger is building these microphones himself, and doesn't advertise at all; this is the reason why he can keep the prices so low, and why you don't hear so much about them.
Trevelling with the CM3s
On March 2018 I travelled to Lithuania for a month, I was commissioned to compose a solo guitar suite (to be released in March 2020). So the two tiny CM3s, in their practical plastic cases; although unnecessary for the purpose of my work there, were proven to be great tools to have.
My only regret is that I didn't get to record in this beautiful church, but with -28 degrees Celcius, maybe it was a good decision.
Here are two of the pieces that I recorded there, pluged into an Audient iD14 (read my review). The CM3s, togheter with the iD14 make a compeling and affortable pair for travelling guitarists.
Closing Thoughts
After owning a pair for about two years now, having recorded my guitar, cello, solo piano, a piano trio with violin and flute, as well as several voices and a choir; I can honestly say that I can comfortably use them in any situation. I recommend them without hesitation to beginner and intermediate recordists with a sane budget.
My only complaint would be that you need to pair them with a decent preamp as they are not very sensitive. When I compare them with Schoeps, DPA or Neumann microphone that cost 10X more, I find that they are a little less detailed especially in high-mids and highs. But, for the price, or even for microphones that cost less than €1000 a pair, I haven't found anything that comes close for recording acoustic and classical music.