How to Improve your Board Recording

Although mixing the show for the house is our primary concern, there are many times when it is necessary to record it as well. This could vary from a copy of the PA output for posterity or post-show evaluation to a full-scale multi-track recording for commercial release. There are many ways to accomplish this depending on the purpose and a few ways to increase the quality within the imposed limitations.

Keeping It Simple
The easiest way to record a live show is to take a copy of the mix output from the FOH desk, recorded direct to 2-track. This could be driven off a matrix or dedicated record output, fed from the stereo bus, but should be sourced before any system EQ is applied. The advantage of this method is that it is really easy to achieve and the mix is already set. The disadvantages are that the record mix is generally not so good as it will be adjusted to compensate for the imbalance of stage sources in the house. Generally, the vocals must be mixed relatively loud and anything with onstage amplification, such as electric guitars and bass, will be mixed relatively lower. This will result in a mix that is vocal heavy and band light.

This imbalance depends on the amount of sound coming off the stage, so the problem will be exacerbated in small venues with loud backline. Larger venues and quiet stages will suffer less from this problem, but you will still find that a show mixed for reinforcement may require a different balance to a show mixed for a recording.

Mobile Pro Tools Recording

As the vocals are often the most important part of the music, and most often out of balance on console recordings, a simple way to fix this is to record a mix of the vocals to the first track, and everything else to the second track. This could be done by routing appropriate tracks to audio groups, leaving everything post-fader so any relative level and EQ changes are tracked onto the recording. To create a balanced recording now requires mixing the 2 tracks down to a single feed.

An alternative and more complex solution is to set up an auxiliary feed to the recorder. This should preferably be a stereo bus, but must be post-fader. As a starting point, set all the necessary channel auxiliaries to 0dB and pan each send where desired. This will result in a record mix that has an identical balance to the PA mix, tracking any changes made to the PA, albeit with separate control over stereo spacing. Any adjustments to record balance can now be made on the auxiliary sends to compensate for stage noise, while still tracking the live mix. You might turn the vocals down by 3dB and the backline up by the same amount to get closer. This method is fiddly to get a really good mix without any kind of monitoring isolation and lends itself to refinement night after night, but it can work well with some perseverance.

A similar technique which simplifies the process is to send related channels to a number of audio groups, which all feed a stereo matrix record feed at 0dB post-fade. This then gives you record stems with level control via the group master faders, while retaining relative levels within the groups.

A desk recording can be enhanced significantly with ambient microphones. A pair of cardioid condensers set at FOH in a coincident pair or ORTF configuration will give a much better representation on tape of what is happening in the house. A console output will be necessary, mixed in with the ambient microphones appropriately to add definition and give a punchier mix as the room acoustics may smear the arrival times and add too much room noise at the stereo microphone location. Bear in mind the distance between stage and FOH will require a delay to be applied to the console record feed to time-align it with the ambient microphones. Sound travels at roughly 340 meters per second, which means that it takes about 3ms to travel 1m.

When recording with ambient microphones, I find it useful to record 4-tracks to a recorder; a stereo feed from the console and a stereo feed from the ambient microphones. These can be combined, delayed and processed at a later date as it can be hard to get the balance right in the field with noise and time limitations. If you have only 2-tracks to record to, you must make a choice between 2 mono feeds (console + ambient) or a stereo mix of console/ambient.

There are a great number of different media formats that can be used for making board recordings. These include CD-R, MiniDisc, DAT, Flash Recorders or computers to name a few. There are advantages and disadvantages to all of these formats relating to size, cost, recording time, flexibility and reliability. Your own situation should dictate the best format to record to.

Personally, I find using a laptop computer the best solution for making board recordings. It enables control over the number of audio i/o by selecting the right third party audio interface, it’s portable so is not necessary to rely on local production providing the correct equipment, it is capable of recording many hours and simultaneous tracks of uncompressed audio without stopping (providing plenty of hard drive space is allocated) and at the end of the tour, I do not end up with a large pile of media but rather a carefully organised directory on my hard drive. When stored on a hard drive, it can be converted to MP3 for sending over the internet, burnt to a CD or transferred via flash drive.

The biggest drawback with this approach is reliability, which can vary depending on the specification of the computer. There is no reason why a high spec dedicated laptop will not be as reliable as any standalone recorder, but a multi-purpose laptop that is also used for day to day tasks may not be as reliable. If absolute reliability is required, a different solution or a backup may be necessary.

Remember that digital data does not reliably exist unless it is in at least 2 different locations. Hard drives are notoriously untrustworthy and if you have valuable data, it should be backed-up to a separate hard drive or other backup solution regularly. You have been warned!

In order to make live recordings suitable for broadcast or commercial release quality, it will be necessary to multi-track record or provide a separate isolated mix engineer with access to all inputs.

The most flexible way is to take an extra microphone split from the PA stage box. This supplies a full set of microphone level feeds to a recording system, which then need to be amplified and tracked. This method gives the most control to the recording system as they are seeing direct microphone outputs at microphone level. It is perfectly acceptable to split a microphone 3 ways with a passive split, provided the recording system is on the same technical earth as the rest of the system. If it is not, transformer isolation may be necessary.

This method is often used by broadcast and live recording companies as third parties. The PA company supplies an additional set of tails from the line system and the third party bring in an additional active split or other buffer for transmission to the truck, where it may be multi-tracked or mixed down to 2-track or air.

The Mixdown Console

This method usually requires another person to operate and monitor the recording system, as it will at the very least require someone to set preamp gains. This may be too much for the live engineer to consider along with their main responsibilities.

It is possible to multi-track without introducing another split by utilising the FOH or monitor console channel direct outputs. These should be set pre-EQ so that the record feed is not altered by EQ, dynamics or fader changes made for the house. This may require changing internal jumpers on an analogue console. In effect, the recorder is seeing the microphone with gain applied at the console head amp. In this situation, the mix engineer must be very careful with head amp gains, as any changes mid-show will track to the recorder and cause problems when mixing down. They should also ensure that the head amps are uniformly gained or the record levels will be sporadic with less than optimal SNR.

Interfacing a multi-track recorder to a live console is made easier with digital consoles being so prevalent today. An analogue desk requires a multi-way loom to be connected between console and recorder, whereas most digital consoles have a plethora of options for digital interconnection. This may however end up causing more headaches than otherwise! If MADI is supported by both devices, 64 channels can be transported with a single BNC cable, or alternatively just 8 cables via the ADAT Optical Interface standard. These digital interconnects also benefit from a word-for-word transmission from console to recorder, with no analogue/digital conversions. The input level seen on the console is the same on the recorder, so no effort is required to keep an eye on recorder input levels.

It is beneficiary to set up ambient microphones for multi-track recording, but as the technique is different to the method described above, a different mic’ing technique is required. A coincident pair at FOH supplementing a FOH console mix is designed to fill in the pieces missing from the PA mix, whereas a multi-track recording has ultimate control over the mix, and does not need these areas filled-in. It does need ambient microphones however to give a sense of the live environment. For a multi-track, these microphones would typically be placed at the front of stage pointing towards the audience. 1 per side may be adequate, but more may be required for large venues or a fuller picture.

I have found that shotgun microphones pointing into the audience make good ambient microphones with plenty of rejection of the PA, but they must not be aimed too close as their high directionality will tend to pick out individual audience members rather than the bigger picture.

As always, there are many ways of doing the same job. The method you choose should be based on quality required, ultimate intent of the recording and time and equipment available to you. If your band just want to listen to what they’re playing after every show, a multi-track will be overkill, but likewise, a stereo console output does not make a commercial release quality recording.

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