PDA

View Full Version : Help Needed: Speaker Placement.



MARKEG
14-11-2003, 08:10 PM
Hi everyone. The problem is I've just moved house and I'm worried about nodes/positioning etc etc. So I've drawn a sketch of the room (which is also thick full of records hehe) with all the measurements. Obviously I need to know the best place to put the speakers - which both rest on one of those quicklok desks (also drawn at the bottom). oh and I've put where I'd usually sit too.

Can anyone advise me? I've looked at node calculators and I really don't understand them too well. I mixed down a track for the first time the other day and it sounds bloody awful. I need the right positioning for sure.

http://www.blackoutaudio.co.uk/studioroom0002.jpg

audioinjection
14-11-2003, 08:27 PM
All I know is the best way to have your nearfields positioned is to have them make and equal triangle (lets say). Example, if you have your monitors 3 feet away from you, you want to have them 3 feet apart from you(hope you understand), and have them the height of your ears, sitting down.

does that make sense?

MARKEG
14-11-2003, 08:40 PM
thanks but i the speakers are fixed on the quiklok desk and i've never had a problem in my old house. i'm super careful with triangle thing - always have been - and always sit at the right distance. perhaps I should have been more specific. the real thing i'm asking about here is advice to stop bass cancellation from nodes. which is the best wall etc... and what problematic freq's exactly should i look out for in the position I choose...

Also is there a good tonal type test you can do - i'm sure i remeber reading about this before on here but can't find it.

MARKEG
14-11-2003, 08:45 PM
hold on.. you're right... i need to make the triangle better....

Dustin Zahn
14-11-2003, 08:46 PM
I heard something about keeping your monitors at least 1ft away from the walls, and if you have them closer, plug a port or something like that. Just search the net, I'm sure there's plenty of great sites dealing with this.

MARKEG
14-11-2003, 08:47 PM
but any other advice on which wall is best?

Col
14-11-2003, 10:01 PM
mark get hold of this book, basic home studio design, written by paul white, its £5.00, u might be able to get it from waterstones, or borders in town. i think you'll find everything u need to know within it, it covers room acoustics, monitoring, soundproofing etc.

Col
14-11-2003, 10:14 PM
heres a few tips ive taken out of the book:

like dustin said keep the monitors 1ft away from walls.

keep your monitors as far as possible from the corners and side walls.

set them up along the longest wall because this will reduce both the intensity of any reflections reaching the listener and the extent to which the direct sound is compromised by the reflected sound.

so by the sound of things, it seems the most logical place for the monitors would be directly infront of the chimney (1ft away of course) purchase some thick curtains for the window, or even make a wooden shutter. some acoustic tiles for the empty wall, and bob should be your uncle. well thats my theory anyway.

i got the edit option on this post for some reason. so i used it, after i misread the diagram. ha ha

get that book though mark.

audioinjection
14-11-2003, 11:01 PM
you can actually use your records for a diffusion wall if you put your records behind you. you want to have your room as uneven as possible.

miromiric.
14-11-2003, 11:15 PM
place your desk in the middle f the room if u can. so u get at least 1 feet on the side and 3 feet frm the rear.
make a triangle but dont make it to big.

DJZeMig_L
15-11-2003, 01:50 AM
I would mainly go 4 miromiric's sugestion...

Remind me which speakers u have... Alesis M1 Mk2 right...?

there is no prob getting' em close 2 the wall just cover th ports on each...


I guess I would draw out a good Mic (get a m8 2 lend ya one of them mf expensive 1s).... set ti up where yer ears would b. Now get wavelab, Sx, what ever play about 1 minute of whitenoise while recording what u get on the mic (which is placed where yer ear generally are) 2 another track...

Try this for 3 or 4 of the different placings on the room.... get a spectral analiser... and check which is closer 2 the linear reprod....


Probably none will but u can check which "room eq" suits u best!!


Hope this helps...

I'm betting on the side wall with yer back 2 the chimney.

Z

Basil Rush
19-11-2003, 11:34 PM
play a sine wave up through the low frequencies, if you are feeling cunning you can figure out what frequency you are listening to and then compare that against your room mode calculator. should line up more or less, also you can hear any big problem freqencies and make allowances when you are mixing your bass in that key.

stuff in A sounds horrible in here.

and you can always just go with the sine wave solution and just move the speakers around till it sounds best.

there's an mp3 sine wave rise at www.genelec.com you can use if you haven't got a synth that gives a good linar slide up..

audioinjection
20-11-2003, 12:17 AM
I think the freq's you wanna check are 100Hz, 1Khz, and 10Khz

MARKEG
20-11-2003, 02:00 AM
absolutely great - thanks guys...

MARKEG
20-11-2003, 02:01 AM
basil: http://www.genelec.com/support/testsignal.php

is the one. really good..

duracell
25-11-2003, 02:21 AM
Hi mark
I don't usually post here but i thought i could help you here cause i've been
studying room acoustics a lot lately.

ok

first off
your speakers should ALWAYS be positioned to the lenght of the room rather then the width.in your case they should be up against the 9 feet wall
(depending on what monitors you use , you might want to move them a little bit away from the wall).The reason for this is bass reflections :
since low freq waves (bass) are much longer then high's , reflections of the
walls cause phasing and bass cancelations (which i think is your case), thus
you need as much lenght as you can get.

Second thing is room shape.You'll need as little standing waves as posible
so you should have something to brake off paralell surfaces.but since you
already filled the room with records and equipment there's not much you can do about it.what you can do is to put things(gear,couch,whatever)
in random places so that bass can't reflect more then twice(floor to ceiling).

Next problem is corners. Bass frequencies act funny in corners and actually
increase in amplitude when reflected, so what you need to do is to put bass traps in 2 corners of the wall behind you.
These things have shape of a tunnel and are placed up against the corners. what they do is ,they kill some of the bass energy and stop it from coming back at you.

umm...yeah

Any diffusion is good and don't put to much of absorptive material, although some is ok.

And for the room tuning you'll need a RTA( Real Time Analyser), pink noise generator and a calibrated mic.But room tuning is a lot more complicated then it sounds.
For that I would hire a pro audio engineer if i were you.

.. i hope this helped ya somewhat.

Basil Rush
25-11-2003, 02:47 PM
Yeah - but as you move the speakers away from the wall you'll get different interference patterns with different wavelengths of the bass. Suggest some kind of experimentation here. If you have the speakers right up against the wall you get a pretty consistent reenforcement of the bass, something like 4-6db and you can adjust for this by rolling some bass off, most active monitors have a switch for this.

If you have them an arbitary distance from the wall you'll find some frequencies are louder than others. The ideal response is with the speaker in free air with no walls, or flush mounted into the wall.

I think so anyway ... there's a book, "The Master Handbook of Acoustics", but it's a bit annoyingly hardcore!

Basil Rush
25-11-2003, 02:51 PM
basil: http://www.genelec.com/support/testsignal.php

is the one. really good..

Yeah, bet you can hear the problems with that kind of thing. What the f*** to do about them once you've heard them is another thing entirely. We borrowed a load of bass trapping once, that didn't work properly.

I made myself a flat panel resonator but got the frequency wrong by 100Hz (these are easy to make and test but difficult to get right it seems).

Bottom end really needs things like helmholtz resonators, but I'm moving house too and can't be arsed till I see what the new environment's going to be like. We are thinking of building it from scratch so...

MARKEG
25-11-2003, 02:57 PM
well good luck basil. also more great advice. in the end i've gone along the shorter wall (the problems i was having were with them on the longer wall). and i've moved the speakers from the wall by 1 ft. i have to say, the difference is incredible. and i can hear the low end like never before.

very pleased i asked about this and even more pleased i did something about it.

BloodStar
04-12-2003, 12:20 PM
Hi,
I've found this link on one of Czech e-music forum.
I hope this will help you:
http://www.johnlsayers.com/phpBB2/index.php
--------------------------------------------------------------------------
O me jeste uslysite !!!

BloodStar
22-12-2003, 12:02 PM
It looks,, it's down,.,now.
Sorrrrryy :oops:

BloodStar
26-01-2004, 02:53 PM
try this one:
http://www.saecollege.de/reference_material/index.html

DJZeMig_L
27-01-2004, 03:13 AM
Try this pdf, quite usefull has it's more on a down 2 earth kind of thing...

http://www.computermusic.co.uk/tutorial/hearnoevil.pdf

Z

278d7e64a374de26f==