Friday, January 6, 2017
Q. Why don't my mixes sound good on a subwoofer system?
I've just finished mixing a couple of tracks and I'm checking out how they sound on different systems. So far I've managed to get them to sound OK (well, acceptable anyway) on my Genelec 1030s, different sets of hi-fi speakers, a boombox, TV speakers and so on. I thought I was on my way to engineering stardom until I tried the tracks on a friend's system which has a subwoofer. Even with the subwoofer turned down a bit, the amount of boomy low bass was incredible and pushed the other frequencies to the back. Do you have any tips on how to prevent this from happening? I guess EQing out the sub-bass frequencies is the trick, but how do you know what you're doing if all these other sets of speakers don't give you a clue as to what's going on?
SOS Forum Post
Technical Editor Hugh Robjohns replies: Do not despair! I strongly suspect the problem is with your friend's monitoring system rather than your mix, especially as it sounds OK everywhere else. Genelec 1030s are pretty good at telling you what is going on at the bottom end, even if you are doing daft things with subsonic rumbles, and if nothing stands out as silly on them, then it tends to point to a bad subwoofer setup.
So, assuming your track doesn't contain stupid amounts of sub-40Hz bass rumbles, you need to help your friend to sort out the standing-wave problems in his room, and to set up his subwoofer properly.
If you can, check your mix on a real-time audio analyser (as found in Steinberg's Wavelab, above) to see what is going on below 80Hz or so. Make sure there are no excessive peaks in the low frequency area — compare your mix against commercial tracks in a similar music style to get a feel for what is 'normal'. I suspect you'll find your track is fine and it is the combination of the room and the subwoofer setup that is the real problem.
A handy way to check for standing waves and the resulting uneven bass response in a given listening setup is to record a simple sine-wave signal from a synth or sound module playing each note in turn over the bottom two octaves. Make sure that all the notes have the same velocity, and ideally, make each note a 'ping' rather than a constant drone.
Play that back over each system in turn and you'll be able to assess their ability to reproduce low bass evenly, and the effect of the room's standing waves. I expect that in your friend's room you'll find some notes set off huge resonant peaks and others disappear completely.
Standing waves are a common problem, and one we come across all the time on our Studio SOS visits, in letters and emails to Q&A and on the SOS Forum. The solution is to set up some proper acoustic treatment in the room and to adjust the positioning of the subwoofer. As a starting point, I suggest you read 'Monitoring & Acoustic Treatment' and 'Choosing & Installing a Subwoofer' by Mallory Nicholls. You also might want to read through some previous Studio SOS articles for some practical examples of room treatment, and searching the SOS web site for terms like 'acoustic treatment' and 'subwoofer' will turn up lots of useful information.