testing my rooms acoustics ?

[logic pro]

Speakers at minimum one foot off the walls.

Not true.

and now to this, perhaps?

whats the general rule...or why not put them away i just dont get the answer , i lerned like 30cm min from the walls (if they are not in the walls)

[antics]

how much of an effect does the room have? I work in quite a large room with some KRK 8s, i know the monitors aren't that clean themselves so is there much point in trying to treat the room? It feels a bit like polishing a turd?

[logic pro]

yes. no.

[jackquinox]

how much of an effect does the room have? I work in quite a large room with some KRK 8s, i know the monitors aren't that clean themselves so is there much point in trying to treat the room? It feels a bit like polishing a turd?

Room size and shape has every effect on the way in which sound waves travel, based on rooms size dimensions you can calculate the mode of the room, based one whats in the room you can calculate the absorbtion, you can also calculate the standing waves and the reverb time the fact is suggesting someone goes out and purchases rock wool (unless you decide to reintigrate a partition wall into your room) is getting beyond the basics of what is being asked, you describe the sound as boxey, you may need to elaborate on that, what part of the sound do you feel has the colouration? what are the dimensions of your room? it seems most posts in this thread are just talking about ways in which you can throw money at the subject which doesnt really work if your just a guy in his bedroom making music with a slightey tinny sound in the background everytime you hear a hi-hat, then again if you have money its a different story, i think the op has to elaborate on there problem.

[Karma_blitz]

thanks guys

[Disco Nutter]

how much of an effect does the room have?

Pretty big!

[macc]

how much of an effect does the room have? I work in quite a large room with some KRK 8s, i know the monitors aren't that clean themselves so is there much point in trying to treat the room? It feels a bit like polishing a turd?

The room has the largest effect of anything in your monitoring chain. At the low end, it's not uncommon to see dips of over 30dB, and very very common to see 20dB. This is due to either room modes or low frequency comb filtering (boundary effects/Speaker Boundary Intereference Response/SBIR). To answer Logic Pro's question about distance from the walls here; it depends. The speaker and listener positions where you have the best balance of room mode effects and SBIR is the right distance. Having the speakers right up against the wall moves SBIR to higher frequencies where they are more easily absorbed. you get a low shelf boost effect from the wall, which is why most nearfields have low shelf controls on them, to conterbalance that. Having them one foot away

After the modal problems, everything is about the time domain. That is, reflections. If you don't have ways of controlling reflections then you're up shit creek. That's why absorptive material is prescribed (as well its use in taming modal problems). It's not about telling people to throw money at it; after moving your speakers to the best place it's about the only way to start to fix problems even if you are a bedroom producer. If you're serious about it, you'll do it. If you're not, then stop moaning and get on with it

Let's explain this in clear terms. Everyone here knows what you get when you put a very short delay on something, right? You get a comb filter! Yay!

Well, no. Try this experiment;

Put some headphones on.
Put a tune on an audio track, maybe turn it down a bit to give some headroom.
Make 6 send channels.
Mute them.
Insert a single-tap delay plugin on all of them.
On each delay, set the mix to 100% wet, zero feedback, no filtering.
Make sure every send is getting full level (ie set the send amount to 0dB/unity gain).
Set the return level on the first four to somewhere between -8dB and -16dB - each one different, all random.
Set the return level on the last two to somewhere between -15dB and -24dB - same again.
Set delay times something like this (rough is good enough);
Delay 1 - 1.5ms
Delay 2 - 5ms
Delay 3 - 8ms
Delay 4 - 11ms
Delay 5 - 18ms
Delay 6 - 22ms

Now unmute the returns one by one, or even all together. Listen to the fucking state of it. This is an extremely simplified version of what your room is doing * . Here's why I chose those delay times.

1.5ms corresponds to a reflection travelling an extra 50cm or so compared to the direct sound - like a reflection from the desk in front of you. 5ms and 8ms are travelling about an extra 1.7 and 2.6 metres - like the side walls and the ceiling (one way or the other, depends on your room being wide/high). 11 ms is 3.5 to 4 metres - so it could be the back wall. 18ms and 22ms could be going wall>ceiling>back wall>ears or similar. All this is done without any calculators, it's just done roughly in my head, ok!

Now let's pretend to put some absorption (rockwool, foam etc) in the way of those reflections, at the specific reflection points (not just all over the room!).

Group the first 4 faders, and turn them down so that the highest one is at -20dB. Ahhhhhhh.... that's better, right?

This is why you use absorption to tame early reflections. There's no way around it, there's no avoiding it. That is, unless you have a purpose-built room that cost you a million pounds... but then you probably wouldn't be reading this. It's not about 'throwing money at it' - it's a demonstrably effective means of improving the sound in your studio by about a million %.

In terms of finding those reflection points, using an ETC is the way. In my (admittedly relatively limited) time with acoustics, absolutely nothing ever ever ever works out how it does on paper, ever. It's a total headfuck of a subject and measurement is the only way to know what is going on.

Good luck chaps. You WILL need it



* without modal or SBIR effects necessairly... if you want to include those then stick stick a big crazy random load of cuts in your low end to get a rough idea

[lowpass]

Great post, think you may have mentioned the ecm8000 before for testing a room, are there any better alternatives for them in that price range or am I going to have to get over my natural prejudices and give in to the mic that Room eq wizard is designed for

[graish]

[macc]

Great post, think you may have mentioned the ecm8000 before for testing a room, are there any better alternatives for them in that price range or am I going to have to get over my natural prejudices and give in to the mic that Room eq wizard is designed for

Pretty much any omni will do - you might have one already.

Of course, there are variations in mic response, but when you do your first measurement you'll see why that is just a drop in the ocean

The ECM does the job though, so...

Look on the RealTraps site for a test of a load of measurement mics, including the ECM. Not too bad, eh

[green plan]

Cheers for the knowledge gravy macc.

[macc]

Pour it on your brain potatoes, and enjoy with a little practice sauce.

Or something.

[TM45]

sub bass is 3-5 metres. normal base if 0.5-2 metres. In many peoples rooms, standing waves are set up, where certain frequencies complelelty cancel, this can be observed when if you walk to different parts of your room, certsin frequencies dissappear. I have serious trouble tith this. in my uni room, it's only 5metres long. This is exactly where most of ym dsubbass sits, which means i get nothing at all in the cenmtr of my room, but at both sides the bas overpowers everything.

people say an equilateral triangle is perfect, but if your room is certain dimensions its pointless. get a couple of baffles (anything to put behind the speaker will do), and this will cancel a majority of standing waves (cause it wont rtelfect). For a dsubwoofer, theres not much ytou can do really except move it around until you;re hearing the loudest (peak pooint to stand ina club or whatever) bass note you can find.

apologies if this is jarbled. im bare fucked >_<

hpe this helped anyww\y.

TM.

[streetxlite]

Pour it on your brain potatoes, and enjoy with a little practice sauce.

Or something.

fully did and done.
i feel like i just gained a level or something

[lowpass]

Pour it on your brain potatoes, and enjoy with a little practice sauce.

Or something.

fully did and done.
i feel like i just gained a level or something

It's all about those experience points, when you get to level 16 you know you evolve right?

[green plan]

Pour it on your brain potatoes, and enjoy with a little practice sauce.

Or something.

fully did and done.
i feel like i just gained a level or something

It's all about those experience points, when you get to level 16 you know you evolve right?

No way? What into?

[streetxlite]

Pour it on your brain potatoes, and enjoy with a little practice sauce.

Or something.

fully did and done.
i feel like i just gained a level or something

It's all about those experience points, when you get to level 16 you know you evolve right?

No way? What into?

("HI! i'm dave from boy in a band now")

Just bumping this. Advice and practice discussed is golden.

[antics]

Yeh add to the <B>bible?</b>

[macc]

Just tweaked that post a little bit.

Not ready for the BIble IMO - nowhere near complete enough as an approach to treating your room. I'll try to write something more formal soon


Seriously though, do that experiment on the cans

[streetxlite]

thinking i'll do a treatment similar to this one: http://www.youtube.com/watch?v=wQ6PecjPTIU
maybe incorporating a couple floor-to-ceiling corner traps. thoughts?