I was looking through my toy cupboard, sorry, gear locker just the other day and I found some microphones that I have not used in a while, an old pair of AKG C1000s. These were some of my first 'professional' mics and my collection has developed and expanded quite a bit since I bought these back in the early 90's but, has changing my mind about how I used different mics over the years really made a difference to the sounds I am recording and has my changing microphones improved my sonic output. In this article I a test 6 different pairs of what I am going to generically call 'Small Diaphragm Condenser Microphones' recording drum overheads. This is not to decide which pair is 'best' but to let you hear how changing microphones can really make a difference.
For this test, I will be using a stereo X-Y configuration over the drums. The capsules of the mics will be at 90 degrees to one another pointing at the bell of the right Ride cymbal and the left Crash. Although the mics are a range of sizes with a bit of tweaking I have been able to get all the mics to be arranged in approximately the same way.
All the mics have been set with 0dB of attenuation and no filters are engaged.
All the microphones in this test have a fixed cardioid pattern other than the Sontronics STC-1, which ship with a set of hyper-cardioid capsules. In this case, there are now 2 recordings for the Sontronics mics. The first using the cardioid capsules and the second using the hyper-cardioid capsules.
Another interesting aspect of this test is the price of these mics. None of them are over £600 per pair and some are significantly more cost-effective. With a bit of digging you can find out the best price in your area, but this is not the aim of this test. Simply take a listen to the audio files below and let us know which recording you like and why. I have done my best to make sure all the tracks are level matched so the level of the recordings should not influence your decision.
When I first posted this article, I have to admit I only posted the Hypercardioid recording of the Sontronics STC-1 mics. The sound of the Sontronics generated a great deal of debate and so we investigated what the problem could be. As a result, I went back into the studio to record a pass with the "normal" Cardioid Capsules. When comparing the recordings it is always important to conduct the same test on all the subjects.
As I sure you can hear, the difference between the hypercardioid and the standard cardioid recording using the Sontronics STC-1 mics is pretty evident. I asked Product Designer and Owner of Sontronics Microphones Trevor Coley why this was the case and he responded with a very full and thorough answer.
When using a microphone with a hypercardioid polar pattern one can expect some relatively dramatic differences when compared to the same, or a similar microphone, with a cardioid polar pattern.
The on-axis pickup field of a hypercardioid microphone is approximately 105º (cardioid is approximately 130º) and this gives the microphone a relatively narrow ‘focus’. Directly on-axis, at 0º, the microphone has a full frequency response however, the slightest move off-axis will result in a significant change in tone.
This ‘focus’ can be very useful when trying to separate or avoid spill from other instruments - in an orchestral setting perhaps, or when miking percussion – but its use requires careful thought and planning.
One other key issue to note is that the hypercardioid pattern is also sensitive to audio from the rear (180º axis), though not as sensitive as the 0º front-axis. This means that the microphone is sensitive to reflected sounds coming from behind and particularly relevant if you are using a pair of microphones as overhead mics in a room with a relatively low ceiling. The additional (reverse-phase) reflections can potentially cause unwanted frequency cancellations and produce a very undesirable result!
An easy way to remember this information is to imagine the microphone behaving very much like a spotlight; a hypercardioid microphone focuses its beam directly towards the source/subject but the periphery is very much in the shadows. If the source is out of the spotlight, it will not be picked-up clearly.
Conversely, a cardioid microphone will provide a much wider ‘beam’ and should exhibit no pickup from the rear. When a pair of cardioid mics are set-up in an XY stereo configuration, both ‘beams’ combine to provide an incredibly wide pickup, providing a full and balanced tonal response across all frequencies.
I now feel these recordings are a fair representation of all the microphones in question. Let us know what you think and which ones you prefer.