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 Schoeps CMC6 MK22
Other than various Neumann microphones, the most used small-diaphragm condensers in classical concert halls and recordings are made by DPA and Schoeps. The philosophies behind their designs are quite distinctive, as are the usual descriptions of the family sound of each brand. Arguably though, they are more similar than different, as they both belong in the relatively uncoloured realm. But the big question remains; which microphone is better for recording the classical guitar.
To try and answer that question, for my needs and tastes, I had to get demo units of their cardioid microphones.
A Cardioid and an Open-Cardioid
The 4011A is a staple performer for many acoustic/classical instruments when a directional pick-up is required, Schoeps also offers a few different cardioid capsules with their Colette system suitable for a variety of uses. The MK22, which I chose for this shootout, is an open-cardioid. Schoeps describes its characteristics as a combination of the natural low-end of an Omni pattern with the benefit of cardioid directionality. In essence, it is a little wider than their standard cardioid capsule, MK4, and offers a marginally finer bass response.
Comparing the Polar Pattern plots of these microphones, I realised that the MK22 is closer to the characteristics of the 4011A than the MK4, making the decision easier, and this comparison quite logical.
DPA 4011A Frequency Response
DPA 4011A Polar Pattern
Schoeps CMC6 MK22 Frequency Response
Schoeps CMC6 MK22 Polar Pattern
It has nothing to do with sound
The DPA 3511A Stereo Kit
This might be a little unfair to Schoeps, but it's not my fault. DPA arranged for me to have for reviewing the 3511A Stereo Kit; a high-quality aluminium case which except for a matched pair of microphones, includes a lot of premium accessories, like their high-quality microphone mounting clips, shock mounts and a long stereo boom. All made with the highest standards and can be convenient in the field.
Schoeps CMC6 MK22 Set
From Schoeps, all I got was a pair of CMC6 bodies with the MK22 capsules. I know that ultimately the sound is what matters most, and I that can be evaluated without any extra accessories. But getting familiar with the DPA system, elevated my experience.
Another observation that doesn’t have to do with sound is that the NEXTEL finish of the CMC6 preamps and capsules is quite fragile, I thought I could scratch them, just by looking at them. In comparison, the 4011A have a more solid feel and seem more durable.
Setting up
As per my usual recording techniques for the microphone duels, I placed each pair at an AB configuration, with 36cm distance between them, 96cm from the ground and around 70cm from the top of my spruce guitar.
By listening to the samples, it is evident that both microphone pairs provide a solid performance. I would be totally satisfied with either, but there are some differences.
Unambiguous precision
The 4011As have a unique way to draw an utterly accurate and almost holographic image of the classical guitar, without any sign of harshness or hardness that is not a product of the performance. The sustaining notes, ring longer and the complex harmonies are captured clearer, like if they are taken apart.
Without sacrificing detail, the MK22 capsules portray an euphonic result. They are fast and analytic, but yet with a smooth and musical character; as if the performance is treated with a touch of kindness.
Au contraire, the DPA microphones will represent with unambiguous precision all the nuances and subtleties of a world-class instrumentalist and a high-grade luthier guitar; exposing likewise any flaws on a player's technique or the instrument. Their honesty can be brutal and overwhelming in some cases. If the source is good, they are going to reveal it; if not, forget about using them.
The Schoeps's offer a gentle depiction of the performance by applying a veil of wizardry and charming sweetness. However with the DPAs, it is like looking at the recording through a magnifying glass.
Noise concerns
My only gripe with the 4011A is the high self-noise. At 18dB-A the noise is not excessive and in most cases not even noticeable, but it can be bothersome for distant miking with softer instruments, or very dynamic musical styles.
The MK22 with 13dB-A of self-noise is almost as silent as my Neumann TLM 193 which have a remarkable 10dB-A of self-noise performance. In reality, most rooms are noisier than any of these mics.
Back to the original question
Honestly, I cannot say which microphone is better; probably neither is. The Schoeps have a sound, as the DPAs and ideally, I would love to own sets of both. In isolation, both pairs should sound stunning, if not, the problem is certainly not on the chosen pair of microphones.
When I'm not directly comparing and analysing them so closely, I believe that their differences are not as pronounced. Saying that, after hearing to my playing and guitar(s) with the 4011As (and 4006As which DPA also sent me), it is difficult to accept anything less realistic.
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.
Austrian Audio OC 818 vs DPA 4011A Stereo Pairs
Austrian Audio OC818
DPA is a high-end microphone company and needs no introduction, they have been around for around 30 years (their capsule design begins somewhere around 1950 with their first measuring microphones) and their microphones have been used on countless recording sessions in the finest concert halls in the world. The 4011A is a small-diaphragm cardioid condenser, praised by engineers and musicians for its sheer accuracy and extremely low distortion.
DPA 4011A
Austrian Audio might be a new name, but the people behind it have a combined experience of over 350 years in audio engineering, or that's what their marketing team suggests. The OC818 is their first creation, a multipattern large-diaphragm condenser microphone built around a hand made ceramic capsule, made to the same critical dimensions as the classic CK12.
Apples and Oranges
Although this test might seem to compare apples and oranges, as one is a small-diaphragm condenser with a fixed cardioid polar pattern and the other is a multipattern large-diaphragm condenser, the objectives are quite clear.
Julian Bream and AKG C24
Slower transient details, colouration and the ability for a lower self-noise floor are well-documented attributes of a larger capsule, while greater linearity and accuracy are closely associated with a smaller one.
When recording a top grade, luthier classical guitar, we wish to immortalise every detail. And thus, for the last decades, the use of small-diaphragm condenser microphones have prevailed. Most of the iconic recordings that defined the sound of the classical guitar have been made with the large-diaphragm condenser and ribbon microphones though. Many of the Julian Bream recordings, for example, have been made with AKG's stereo C24.
Neutrality might not always be desirable.
DPA 4011A Frequency Response and Polar Pattern
Austrian Audio OC818 Cardioid Frequency Resposne and Polar Pattern
The act and art of recording allow for the development of personal aesthetic, as every choice would have an impact on how the recording will be interpreted and appreciated.
Following this path I want to investigate further if the colouration that is usually a characteristic of large-diaphragm condenser microphones, can sometimes be desirable when recording classical guitar.
And furthermore, try to answer the question if a single multi-pattern microphone, with all the versatility that it bears, could replace or subtitute for a collection of dedicated microphones in classical guitar recording.
Details
Stereo Sets
The recordings were done in AB stereo with a 32cm distance between each microphone, I placed each 4011A and OC818 microphones side by side, as I figured that this will bring the capsules closer together. The microphones were on axis with my guitar, at 88cm high and around 50-55cm from the spruce top. The recordings are dry with no EQ, reverb or other processing anywhere.
High-quality 320kbps mp3 streams:
If you’d like to listen to uncompressed wav files, just send me an email.
Click here for more comparisons and a full review of both the OC18 and a stereo pair of OC818.
Disclaimer: Austrian Audio and DPA sent me the microphones for reviewing without any precondition or obligation to write positively about them. This is an honest presentation, driven by a genuine interest and desire to create a classical guitar microphone database.