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Sunday, 3 June 2018

Q&A - Volume One

Hi everyone!

I’ve not been posted for a long while, I wanted to apologise for not keeping you all in the loop but I am back now and I have a great new post for you!

A lot of you message me on a daily basis asking about music creation, recording and various bits of technology so I wanted to answer a few of the most frequent ones I have received lately.

If you have sent me a message in the last few weeks please keep your eyes open on the new Q&A section that has recently been added to my blog! My answers to your questions will now be a click away so, have a little scroll and see anything else you might find useful to know!

For now, enjoy this new update and I’ll catch up with you all soon!
“Why does reverb sound different on headphones?” – Katie, age 17.

I hear people comment upon this regularly, and something I have also experienced myself, you’re not alone! I believe the effect is due to the very different way our brains process sound when it is presented. This is either through headphones, speakers and monitors. The fundamental difference, of course, is that when listening to speakers both ears hear both channels plus the indirect sound bouncing around the room, whereas with headphones each ear hears only one sound channel and no room contribution. So, as a result the different reverb signals in the left and right channels are interpreted as spate sources, not disregarded as part of the general room ambiance, and so acquire a greater prominence within the mix in our perception.

“Sound I avoid placing my tweeters half-way between the floor and ceiling?” – Rob, age 23.

There is some truth hidden in that advice, but it relates to the speakers’ woofers, not the tweeters. The wavelengths of the sound the tweeters produce is so short that it really doesn’t matter, from a room-mode standpoint where the speakers are, the reflected sound will be entirely random and chaotic. It’s generally a good idea to avoid placing the woofers on the mid axis of the room (side/side, front/back or up/down), because of the low frequencies which the woofer produces are likely to be similar to, or integral fractions of the dimensions of the room, so you’re more likely to excite string room modes that way. It’s much better to have the woofers off the centre room axes. The overall height of the speaker needn’t necessarily change, though you might find that you can solve any problems you can hear simply by turning the speaker upside down!

“Why do my final mixes always end up in mono?” – Segal, age 27.

This isn't as simple a question as it may at first appear, because you only need to make a mistake at one point in the signal chain and all the stereo work you've done up to that point can end up mixed down to mono. Assuming that you indeed have a stereo mix set up on your analogue mixer, which you can verify by listening to the headphone output, this can be recorded to a workstation in one of two ways. If the workstation offers stereo track capability, you can connect the left and right outs from the analogue mixer to the appropriate odd/even numbered inputs of the workstation, and record the results directly to the stereo track. This will preserve the stereo settings you created on your analogue mixer.

Where stereo track capability isn't provided, you'll need to record the left and right mixer outputs onto two separate mono tracks of the workstation, taking care to pan the one carrying the left mixer channel fully left, and the one carrying the right mixer channel fully right. Again, this will preserve the original stereo information from the analogue mix, and any overdubs made on the workstation using different mono tracks may then be panned conventionally to any position in the mix. The final mix can then be recorded to a standard stereo recorder by connecting the main left and right outs of the workstation to the left/right inputs of the recorder. Also check for any mono buttons (which usually only apply to monitoring), and for any hidden menu functions in your workstation that may be designed to provide you with a mono mix.

“Is it a good idea to use a subwoofer in my home studio?” – Jay, age 18.

I can think of very few music–making scenarios where you should need particularly accurate monitoring lower than that — and in those few cases you’d need a room that could cope. If your room can’t cope, and you really do need to judge the level of a 30–50Hz sine wave, then it’s a pretty trivial matter to check on a modern frequency analyser plug–in what’s going on.

With this in mind, I’d suggest that you start not by thinking about subwoofers, but by attempting to check what level of bass your speakers are actually putting out into your room: play some bass–rich material over them and stand in a corner of the room, where the bass build–up is likely to be greatest, and walk around the room boundary. If you can hear an increase in very low frequencies, then lack of bass from your speakers isn’t your main problem — and adding a sub will probably just prove to be an expensive way to make matters worse.

If your speakers are doing their job, you need to do something about the room. You say you’ve already installed as much acoustic treatment as you can, but perhaps you can reconsider the nature of the acoustic treatment you’ve installed. To achieve remotely accurate low–frequency monitoring in a domestic space the room must be treated with ample bass trapping. The idea is to absorb low-frequency waves so that they don’t bounce around the room causing all those nasty peaks and nulls. It’s pretty much impossible to install too much bass trapping, but often impossible to install enough!

“Are high-end cables worth the money?” – Jemma, age 22.

The short answer is no, they're very unlikely to sound any better. The longer answer is that there are complexities and subtleties involved that can, in specific circumstances, conspire to affect the sound when using different types of cables and connectors.

In essence, provided that the cable is appropriate in terms of its construction — particularly in having low capacitance and good screening — and the connectors used are of good quality and manufactured to meet the appropriate specifications, then there is no audible difference that I have ever detected reliably. The problem is that some inferior cables allow interference to get in via the cable or connectors, or have some inappropriate properties such as high capacitance, or they are wired in a way which creates ground-loop problems, and in those cases a properly made cable may appear to work better, simply because the reality is that the inferior cable didn't work properly. However, you should be aware that some very expensive cables are not built properly either.

“What is the best way to add sub-bass?” – Scott, age 25.

In any computer-based tracks where you already have the MIDI information for the other parts, there are two core ways to go about this. The simplest would be to add a dedicated sub-synth channel, with your plug-in synth of choice set to output a pure sine wave — usually with infinite sustain but zero release, so that it immediately plays at full volume and just as quickly stops upon triggering/release, unless a longer release is required dynamically — and then copy the MIDI part for your bass track onto that track. You’ll probably need to transpose the notes to the correct octave or to set your sub-synth’s oscillator pitch internally, to make sure that it sounds in the octave below the original bass line.
However, this simple approach can lose some of the articulation of the original synth pattern, so I often find a second method to be better in many ways. If the soft synth you used for your main bass sound has the ability to generate a simple sine wave, create another instance of that synth on a new channel with the same patch, and then change its settings so that it is outputting a basic sine wave, as in the previous method — but don’t touch settings such as envelope attack or release, or portamento. This way, you’ll have a clean sine-wave sub-bass channel, but with dynamic characteristics identical to those of your original bass patch, so the two should layer seamlessly.
Where you don’t have the original MIDI parts and need to recreate them to add sub-bass, it can be difficult to hear the low notes accurately. A good tip is to play or draw in the notes a few octaves higher up, so that you can hear the notes more clearly, and then pitch them back down to the octave that gives you the nice warm sub-bass tone you’re looking for. Sub-bass shouldn’t really need any processing, as a straight sine wave creates nice, round bass, but sometimes driving it gently with a tube distortion plug-in can add some harmonics that fill a gap between the sub-bass and the more tonal elements of your existing bass. It’s very much a case of trial and error here, but do use your ears and a decent monitoring setup to make sure it sounds good.


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