When we did our last video for In The Studio we discussed the basics of microphones. Part of that discussion was that microphones were one of the entry points for inputting and capturing sound in your system. Today I thought we’d do a post discussing two of the next steps of ‘the chain’ (really two possible options for the next step of sound capture). My usual next step for capturing sound from a microphone would be to run them in to an outboard microphone pre-amp and then in to an outboard compressor. This is my personal choice as my mixing boards have inboard mic-pre-amps and compressors that could also be used. Again, we’re going to discuss this in relatively non-technical terms so anyone can have a basic idea of what the equipment does. I’m also not recommending specific brands or models. They all have their strengths and weaknesses and that’s a whole separate discussion.
Let’s start with the mic pre-amps. The simple explanation of a mic pre-amp is that it increases the signal from the microphone so that you have enough signal volume to get a good sounding recording. Let’s look at the pre-amp below:
This is a two channel unit so we’re only looking at one side. First, it has a button to activate phantom power. As we discussed with microphones, condenser mics put out less voltage than dynamic mics, so we need to use phantom power to add that voltage. If you use a separate phantom power unit in line before the pre-amp, you won’t need to activate this. The pre-amp has a dial where you will determine the volume added to the signal going in to the unit (Input) and a dial for adding volume to the signal leaving the unit (Output). The amount of power added to the input is measured by the LED lights at the bottom right and the output power is measured by the needle display in the upper right. You also have a button labeled ‘Gain’ where you can boost the input signal by another 20 decibels. You have a button to reverse the signal phase (if you want to know about signal phase, dig in our archives for the video on recording a snare and phase cancellation). The ‘HPF’ button is a high pass filter. You can use this to ‘roll off’ at a certain frequency – we’ll save a deeper explanation for another time.
This mic pre-amp is a little more high end and allows you to be a bit more specific in adding signal to certain frequencies. These are the toggle switches and dials to the right in the photo. Other than that, the mic-pre works in the same fashion.
After the mic pre-amp, the signal is sent to a compressor. The basic function of a compressor is to regulate the volume peaks of the signal before it moves to the next step. This can keep the signal from ‘clipping’ and adding audible ‘pops’ to the track if a volume peak is too loud. Let’s take a look at one and go through it’s options.
Going left to right. ‘Threshold’ determines at what volume the compressor takes hold of the signal. The ‘Ratio’ determines what the unit does with the volume once it reaches the Threshold. If you select a Ratio of 4:1 it means that once the volume level hits the Threshold, the compressor will allow the output to increase by 1 decibel for every 4 decibels of actual volume. The ‘Attack’ determines how quickly the compressor applies the Ratio and ‘Release’ determines how quickly it stops applying the Ratio when the signal drops below the Threshold. When you apply compression to a signal, you will reduce the overall top volume. The Output dial allows you to make up for this by increasing the overall output from the unit. Finally, this unit also has a ‘Gate’. The Gate allows you to select how much volume is needed to allow the signal to pass through. For instance, when you are recording a vocal, you don’t want anything from the mic to pass through when the vocalist is not singing. You would be picking up unwanted background noise. The Gate shuts off the signal when there is not enough volume going in to the mic. The ‘Rate’ dial allows you to adjust how quickly the gate takes effect.
The compressor in this photo also has a limiter (far right), which means that beyond applying the Ratio, you can set the compressor to cut off the output signal totally at a certain level.
Above and beyond controlling the signal level, mic pre-amps and compressors are used to add color, depth and tone to the signal you are putting through them. Mic pre-amps can use tubes or solid state circuits to accomplish their goal. They can run from affordable to incredibly expensive. Each type will add their own flavor to the sound you are recording. Compressors have been used as an effect to give certain sonic qualities to an instrument – you can find lots of info about using heavy compression on snare and kick drums to achieve a specific sound. Compression can be added at many stages of the recording process. You can add compression to tracks already recorded in the software. You will usually add compression to the final mix to even out the overall volume of the music.
We’ll continue to move through the recording chain in future posts. As always, let us know if you have questions or comments.
We’re back with another ‘messed’ song for your enjoyment. There’s a bit of a story with this one. ‘Seven Nation Army’ was actually recorded before most of the other songs that have been posted. Recording these covers did start with one idea we have maintained with all the songs – recording the tracks straight through to keep it having a more ‘live’ feel. With this song we did what we often do with our own studio songs – record multiple tracks of each instrument for a more ‘full’ sound. So most of the instruments on ‘Seven Nation Army’ were tracked several times (although each separate track is recorded straight through). We also used multiple mics on the acoustic instruments, adding even more tracks.
This tune has twelve string guitar, mandolin, banjo and six string guitar. The percussion is the floor tom from our drum kit and a shaker. Each instrument was tracked several times (except the percussion). Two more mandolin parts were added in the one instrumental section as a ‘lead’ instrument. When we finished recording I realized it would take a while to mix correctly so we decided to record another song without all the multi tracking and multiple mics. And when we finished that song we thought of another, then another……… So it took quite a while to get back to mixing ‘Seven Nation Army’.
As we continue messin’ with songs I’m sure more electric instrumentation while come in to play along with a bunch of other ideas. As always, hit us up with comments and questions if you have any. Hope you enjoy.
Electrostatic Rhythm Pigs play The White Stripes ‘Seven Nation Army’:
Greetings. We’re back with another tune to be messed with. This time we’re honoring ‘Novocaine For The Soul’ by Eels. This was a fun song to work with. I really enjoy the anthemic, sing along nature of the song. Again, we stayed basically acoustic except for the bass guitar. The song has 12 string guitar, bass, mandolin, six string banjo and a little percussion with tambourine and egg shaker.
To give a wider, stereo feel the 12 string guitar foundation track was played twice and panned hard stereo left and right. I think giving a track a wide stereo sound is important and playing a duplicate instrument track is a great way to do it. The two tracks can be very similar, but will almost never be identical (unless you force that with computer manipulation) so you hear each track distinctly from each channel. We worked the same concept with the vocal tracks, recording the main vocal twice and adding two harmony tracks.
Another thing that made this song interesting was the key. We don’t usually change the song from the original key. Specific keys do give songs a certain feel. Major key versus minor key or in this case having the song in D flat instead of D. In the original song they did this by using capos on the guitars. We ended up down tuning the 12 string guitar a half note and transposing the chords so the guitar could be played in first position for a fuller, richer sound. A capo was used on the 6 string banjo. We also added a second mandolin track that acts as a ‘voice’, along the lines of playing a guitar lead.
We may not have said this before, but all the Messin’ songs are played by Electrostatic Rhythm Pigs. You can find these songs and the band’s original music on our SoundCloud account (we have links on this site). We’re also slowly adding all the band’s songs to our YouTube channel (here’s a link to our YouTube channel): https://www.youtube.com/channel/UC0vVN4p_KzvLg1DEuUSJoqw
This is the season for sharing. So please share our songs and videos with your friends. Add them to your Facebook feeds. Become a follower of our blog. Email us with questions or comments. We really appreciate your support.
Welcome to Episode 8 in the ‘In The Studio’ series. Today’s topic is how to create mixing options for yourself during the recording process. A couple things to add about the process in the video. In the video the guitar sounds you hear have not been EQ’d on the mixing board. You can magnify the differences in sound by tweaking the EQ on each microphone using the mixing board. You can also add more diversity by adding effects units in the line between the guitar and amp (this will make more sense after you watch the video). As always if you have any questions or ideas, let us know.
Music tech advances as fast as you can blink. Check out this video from Beck covering David Bowie’s ‘Sound And Vision’. The interpretation is cool enough, but the tech behind it is remarkable. It’s the recreation of a 360 degree immersive environment using state of the art recording and an old but not that well known recording technique called binaural recording. Binaural is very different from stereo recording because it takes in to consideration the natural way a human head hears sound. The Sound and Vision project takes your ears in to that natural recording space as well as letting you travel through the video visually. You can now be in the concert space without leaving your home. It won’t be able to replace the full body experience of live music, but boy are they getting close.
Here’s the video:
I’ve also included an article discussing the tech involved: