Bass ports and monitors

[Skol303]

PS: I should add that you guys are producing great mixes anyway... despite any problems with your mixing environments! (or the colour of your leather sofas)... so always keep that in mind

I found myself disappearing down the rabbit hole of acoustic treatment a few years ago until a mate of mine just shrugged and said, "well your mixes sound ok to me". Since then I've continued my pursuit of acoustic nirvana, but with less of a crazy look in my eye.

 

[Mornats]

I'm mostly just whizzed off that I spent £320 on my Yamahas and they're the least used of my mixing tools! They sure sound good when I'm sat at the back of the room though...

So for the bass trap I'm thinking at least 20cm deep like you said, and as deep as I think I can get away with. Height wise 70-80 cm would cover off where my head and speakers are at with lots of room for movement. For the width, would I have to have it directly in front of both speakers, or just wide enough for me? It's the difference between it being 190cm and 110-120cm.

Actually, I just checked the dimensions of that stuff on the Homebase site. It's 45.5cm tall and 120cm wide so that's about right. A little extra height would be great but that could do it. 10cm thick and 8 in a pack so could go 80cm thick although that would be a bugger to store away... Or 4 deep (40cm) and stack them on top of each other to create a 90cm by 120cm by 40cm trap. Again, that's a bit big to store somewhere! Could double up as a nice footstool though?

[Skol303]

The more coverage the better when it comes to bass traps, so built is as big as you can. It at least needs to cover your head/ears and give you a little room to move at the mix spot. Better still if it also covers the direction of the monitors; but that might not be practical in terms of size.

What you're basically doing is creating a treated back wall behind your mix spot, to help deal with rear wall reflections that are often the most troublesome. You're going to get a whole bunch of other reflections in that room without other acoustic treatment - basically any area of wall/ceiling that you can see from your mix spot will cause reflections - but we're not looking for perfection here; we're just trying to help reduce the null that's sucking the bass out of your Yamahas at that point in the room. I reckon a suitably chunky bass trap will buy you around +10db of level (based on my own experience of trying to treat a -30db dip in my room). Not huge, but it can make the difference between certain low end frequencies being at least audible, rather than nonexistent.

I'm about to use this exact this same method myself, so if you want to wait a week or so I can report back here with my own findings and some frequency measurements. My own back wall is pretty much treated as far as it can be, so I'm going to build one or possibly even two free-standing bass traps that I can put behind my listening spot when mixing - adding a second or even third layer of rear wall treatment (adding up to >60cm of mineral wool).

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PS: there's a totally different method of treating low end frequency balance that involves using multiple subwoofers. Really good paper on this by Salford University (available online last time I checked); works in rooms of all sizes. Tricky to set up and of course expensive; hence I haven't really gone into it here or tried it for myself. One sub on its own can also help 'fill in' some of the modal nulls, because the sub can be positioned elsewhere in the room away from the main monitors (low frequencies being omnidirectional). You needed a treated for that however, whereas with multiple subs room treatment is less essential.

Honestly, when you start getting into this stuff it's worse than GAS  

Edited February 9, 2018 by Skol303

[Mornats]

I can wait a week  Would be awesome to hear how you get on and of course any tips will be appreciated!

[lurksalot]

On 2/8/2018 at 21:10, Skol303 said:

 

A very rudimentary test you can try is play some low frequency tones (say, somewhere around 60-100hz) or play a track you know well that has a lot of low end - and walk slowly around the room. Listen for where the bass sounds boomy, where is sounds weakest and where is sounds most even - the latter is your new listening/mixing spot! I just hope it's not in front of the TV  

Well a very interesting 30 minutes scooting round the room on a swivel chair😳

Bizzarely I never found a boomy spot, but the place where I normally listen is very bass light, 3feet further back is much sweeter. 

This might be a good development young Skol my lad 👍👍

 

[Skol303]

^ You're welcome Lurks!

Where you sit and where your monitors are positioned makes a BIG difference. Just a few feet (or sometimes even inches) can make an audible difference in sound.

[charic]

Not to teach anyone to suck eggs but it's worth remembering in the world of mixing that "sounding better" isn't always better

 

[Skol303]

2 hours ago, charic said:

Not to teach anyone to suck eggs but it's worth remembering in the world of mixing that "sounding better" isn't always better

 

Absolutely. "Sounding better" is in fact a lie  ...what you want is for your sound to be as accurate as possible.

But in the absence of acoustic measurements, the best you can do is try to find the sweet spot by ear.

[charic]

If sounding good was a priority I don't think they would have sold a single set of NS10s

[Skol303]

1 hour ago, charic said:

If sounding good was a priority I don't think they would have sold a single set of NS10s

Indeed! Despite obsessing over acoustic treatment etc, I do the bulk of my mixing on crappy earbuds and a pair of Auratone copies: fairly terrible-sounding speakers that accentuate the mid range, but once you get something sounding good on them you're 95% of the way home