Recording : Double bass (the stringed instrument, not two kick drums)
I’m finally back with another tutorial. It’s been a while since I posted anything on here because life happens. But I’m back. So yay!
When preparing to record double bass, you have to first consider what the musical context is going to be.
Are you recording a jazz trio? Are you recording solo double bass? Are you going to track a rockabilly or bluegrass band?
Whether you play arco or pizzicato also determines how you place the microphone(s).
Something else you need to keep in mind is how the bass will be recorded. If the bass has its own space, without any bleed whatsoever from other sources, then you can experiment with mic placement.
If this behemoth of an instrument will share the room with other instruments, bleed between microphones is a true challenge.
For this post, we’ll assume the double bass has its own room and it’s played pizzicato.
If there’s a demand for it, I’ll write an article maximizing separation between instruments and microphones in a shared room.
Which mic do I go with?
Go for a small diaphragm cardioid condenser as they capture much more detail, providing a more faithful reproduction of the instrument.
A cardioid microphone captures mainly what it’s facing towards, and rejects anything coming from behind. There will be some room reflections coming in from the sides of the microphone, but not enough to overwhelm the direct sound of the instrument.
If the bass has a mic or pickup installed in it, record that as well; sometimes you get a little something extra that the mic doesn’t capture. Be careful with the phase coherency between the two. (Check out my phase coherency video to see what that is)
Where do I place the mic?
If you set up a mic, listen to how it captures the instrument and decide it sounds great, chances are you’re missing out on an even better sound.
Don’t be lazy and/or scared of moving the mic to a different position.
Mic placement is the best way to change how the instrument sounds like when recorded. You might like the first placement best, but you’ve at least looked for a better sound.
Since the low end dominates the spectrum, capturing the mid and high frequencies in a way that balances it is difficult. Moving the microphone even half an inch can drastically change the sound you’re getting.
Remember that turning the microphone off-axis changes the frequency response. If you’re using a small diaphragm condenser, the sound will get quieter.
On the other hand, with a large diaphragm mic you get a loss of high frequencies. This can be useful if you want to reduce the finger noise or the slap sounds.
As a starting point, place the cardioid mic between 12 and 18 inches (30-45cm) away from the bridge. Make sure the mic is pointing directly at it.
Moving the mic closer or farther from the upright allows for more or less room sound to be heard.
Angle it towards the fingerboard for more definition and clarity; do the opposite for less.
Move the microphone side-to-side to balance the volumes of individual strings. Additionally, this horizontal movement can help fight boomy resonances.
WARNING: Stay away from the sound hole. Seriously. All you get is nasal and marshy messiness. Now, unless that’s what you’re aiming for, stay away from the sound hole.
Double trouble? No. 3-to-1
If you are recording using 2 microphones, make sure you follow the 3-to-1 rule.
When using 2 microphones to record a source, you normally get optimal results by placing the second mic 3 times the distance from the first mic that the first mic is from the source.
An easy example: if the first mic is 1 foot from the source, the second mic should be places 3 feet from the first mic.
Here are a couple of ideas on what you can use two mics for:
If you want to add more finger sounds, place the second mic higher up, pointing down at the finger.
If you want to record the sub frequencies, place the second mic further back in the room by several feet. The really low frequencies need a looot of room to fully develop.
For example, 32hz has a wavelength of 34 feet (10.4m); that’s the lowest frequency a double bass with a C extension can achieve. 100hz needs about 10 feet (3m) to grow. 440hz, our beloved tuning reference, only needs 2.5 feet (0.7m).
In this specific use case, you’ll have to remove the room frequencies from the second mic. That’s okay, though, since all you want is the low end.
How do I record it?
Even though the double bass is an extremely dynamic instrument, don’t compress it while recording; save that until mixing. Even one mistake can ruin your recording.
Record at 24bits and aim for the meters to sit between -12 and -6db. Why these numbers? So there’s a bit of a safe zone about -6db in case there are some unexpected peaks.
As long as your interface is good enough, though, you can record even quieter without the sound quality suffering from it. Stay safe.
Make sure you get the sound you want to use in the final mix AT THE SOURCE. Don’t think you can fix it in the mix…you usually can’t. All you can do is patch up some issues, while creating others.