Many people think of stereo microphones as something you use as a room or ambience mic, and while stereo mics are great for this, they can also very useful when recording much narrower sounding source material. In this article, I’m going to let you hear four different stereo microphones used to record a simple acoustic guitar chord progression. This is not a shootout, it’s an opportunity for you to hear some very different microphones and decide which attributes of the recordings you like or don’t like. To compare these mics would be like comparing Apples to Car Tyres. You will soon see what I mean.
What Is A Stereo Microphone?
A stereo microphone is a microphone that can record two (or more) signals at a time using two (or more) diaphragms. The benefit of using a stereo mic over two mono microphones is that stereo mics are normally designed to get the two diaphragms as close to one another as possible thus reducing phase issues between the two diaphragms and the resulting stereo recordings. The obvious downside is that in most cases, stereo mics always record to two channels. There are some exceptions, but we can come onto that later. The other drawback is that due to having almost twice the number of parts, many stereo mics are quite expensive. I’m sure we have all see the tour of the Blackbird Studio tour video with John McBride playfully throws a priceless stereo Telefunken 251 at the cameraman (3:23).
For this session, we have four mics to play with. The two most conventional mics are the Vanguard Audio Labs V44S and the Sontronics Apollo 2. The other two microphones fall into what we might call the smart or modelling microphone category. These are the Townsend Labs Sphere L22 and the Antelope Audio Edge Quadro. I’ll let you know how each of these beauties is being used and set up as we listen to each example.
Getting It Down
To keep things reasonably fair, all the mics were recorded through my Antelope Audio Goliath HD Gen 3 interface via my HDX card. The reason I used this and not my Audient console is that later on, I need 4 digitally controllable mic pres. The Goliath HD gives me 16 of these so I have plenty of scope for Jivey levels of overkill if needed. Also in the name of fair play, the gain of the mic pres was set to +30dB for all the recordings. It turned out this was a good nominal level for all the mics for when I and my Patrick James Eggle acoustic guitar were put in front of them.
All the audio files are also downloadable so you can line them up in your DAW for a better comparison if you so desire. The original session was recorded at 96kHz 32 bit the downloads are however only high bitrate MP3. No processing of any kind has been applied to these recordings.
Vanguard Audio Labs V44S
The V44S, by Californian company Vanguard Audio Labs, is a dual large-diaphragm FET condenser mic. The upper capsule can rotate through 90 degrees to allow different stereo configurations and each capsule can be set to either Cardioid, Figure-8 or Omnidirectional allowing X/Y, Blumlein or Mid-Side recording techniques from a single microphone. In this example, the two capsules are set to Cardioid with the capsules set 90 degrees to each other an at a 45 dress angle to the instrument (X/Y). The guitar is about 12 inches away from the mic which is pointing between the 12th and 14th fret. This is the same for all the examples moving forward.
Sontronics Apollo 2 Blumlein Ribbon Microphone
The EMI (Abbey Road) engineer and recording engineer Alan Blumlein was a true innovator the grandfather of many modern recording techniques including the one his name was given to - Blumlein stereo recording. Blumlein stereo is where we take two figure 8 pattern mics, place them at 90 degrees to one another and at 45 degrees to the source. Ribbon mics are particularly good for Blumlein recording as they naturally exhibit a figure 8 polar pattern. The Apollo 2 is the second in the Sontronics Apollo line and has two ribbon motors fixed at 90 degrees to one another inside a mesh housing and as you might expect from a ribbon mic the output is warm and dark and nothing like as bright or delicate as that from a large-diaphragm condenser.
Antelope Audio Edge Quadro
Antelope Audio is the newest player in the modelled microphone market but they have come in hard with a range of single and dual diaphragm designs and the behemoth that is the Edge Quadro a twin capsule, quad diaphragm 4 output microphone. Yes, this thing records to 4 channels and so requires 4 mic preamps. The following examples have been recorded with the capsules at 90 degrees to each other and 45 degrees to the instrument (X/Y) with the polar pattern of both capsules set to cardioid. The first recording is the Edge Quadro in its “naked” mode. No mic models are being applied in software post-recording.
Cracking The Code
For licensing reasons none of the mic modelling companies can name their emulations after the real thing, but it isn’t too tricky to work out what the models are supposed to be. In Antelope land if it says Berlin read Neumann and if it reads Vienna read AKG. So below with have the exact same take as the one above with first a Neumann U67, then an M49 then an AKG C12 finally the AKG C414.
Townsend Labs Sphere L22
The final mic in this recording selection is a bit of a wild-card as so far, all the mics I have used have had two dedicated microphone capsules (or ribbon motors). In the case of the Townsend Labs Sphere, there is only a single dual-diaphragm capsule. However, with the help of the very clever real-time AAX-DSP Sphere 180 plug-in, we can emulate a stereo microphone in software and monitor this as we record. Later, if we are not happy we can change our minds and change the mic type or polar pattern when we come to mix. It has to be said this is not officially a stereo mic but it does do an amazing job of emulation two mics or different mics in a stereo field. Technically speaking the two opposing diaphragms are at 90 degrees to the source but the Sphere 180 software allows us to reconfigure the mics into a conventional X/Y configuration. If you want to find out more about how to achieve this check out the reviews and tutorials lower down the page.
No Need For Bletchley Park
Once again Townsend Labs have gone with a slight spin on the naming convention so just in case you can’t work it out, LD-251 is a Telefunken 251. LD-67 NOS is a Neumann U67 with a New Old Stock valve inside. The LD-47K is a Neumann U47 and finally, the LD-017T is a Russian Soyuz 017 valve mic.
No matter which mic or which technique you like from the above examples the thing I really like about all the above examples is the interesting stereo image you get and the slight stereo movement in the sound as the player moves ever so slightly as they are playing. Yes, all these examples are panned hard left and right so the right-hand side of all of them is slightly louder do to the nature of how the sound is projected from the instrument this was just for demonstration. If these tracks were being mixed for a final recording you might choose to pull the stereo in a little to make the image more central but I like how the performance moves slightly in the stereo field.
If it came down to it and someone held a metaphorical audio gun to my head, I really like the Sontronics Apollo 2 recording. It has much more depth and tone than the others, but hey, I do like ribbon mics on acoustic instruments. The Vanguard V44S has a nice poppy kind of vibe to it. It’s nice and bright but you still get the tone of the instrument. The Edge Quadro and the Sphere are amazing solutions if you, like me don’t have a mic locker with £10,000 worth of vintage mics in and even if you did, would you have matched pairs? Mic modelling technology is truly amazing and as I have said before, it really does not matter if you think the Sphere U67 sounds like a real U67, it’s the fact that we now have the ability to change the mic tone after the recording has happened that is a truly amazing thing. For me, one of the best things about mic modelling is that it has caused the creation of some really very good, yet neutral sounding and affordable microphones. The Sphere and the Edge recordings with no emulation sound great to my ears. Let us know what you think in the comments section below.
Find Out More
If listening to the examples in this article has sparked your interest, you can find out more about some of the microphones featured in this article below.