Calibrating studio monitors. How To ?

[Terry Wetzel]

Good morning. I have noticed a difference in perceived volume level between my right and left studio monitors. A slight difference but noticeable. The right side seems lower than the left when I listen in mono with all faders straight up. (My room is not treated). I am using LSR 305's. Are these speakers sold as a matched pair? I own a Rolls MO2020 test oscillator. Can anyone explain to me, in layman's terms, the procedure for calibrating my monitor speakers using the stated equipment so they are equal as to perceived volume output? What test tone should I use, Sine or square? What frequency, (1K or 10K)? Finally, How should I use my Radio Shack sound level meter to determine the results? (Before anyone asks, my hearing is ok for a man of my age. I have my ears professionally cleaned once a year).

[Wireline]

Try this: using a source you KNOW to be balanced on the stereo field and across the audio spectrum

1) speakers off, make sure your sound card is showing balance. Sometimes the left/right lock can come undone...
2) speakers still off, make sure the gains for left and right speakers is exactly the same, and that the connection cables from sound card to speakers are perfect
3) speakers ON, re listen.

If your equipment works well, you may need to start looking for things in the room itself that can cause this, such as being closer to one wall than another, different wall surfaces, etc, and correct those

[29CountsNY]

The first thing I would check is the volume control on the back of the speakers. Make sure they are both up all the way and see if the levels are still off. Then make sure that both are set to +4 dbu and not -10.

After that, I would send Pink noise out each speaker (one at a time) at whatever level you want to calibrate to (i.e. -18dBfs or -20 dBfs) while holding the Radio Shack meter at the listening position and then adjust the volume of the speaker so it registers roughly 85db SPL. The Radio Shack meter should be set to C Weighting.
If the levels are off, adjust the volume knob on the back of each speaker till they are both playing at the same level.

Also, make sure the big silver knob on the Focusrite is all the way up!

[Terry Wetzel]

Thanks 29CountsNY. Is pink noise the same as the output of my Rolls MO2020? If not, where can I find a pink noise generator? Not to be contrary but I have read that the Sound pressure level meter reading should be read on the A weighting scale,(?). One of the first things I did when the problem was noticed was to turn both speaker volume knobs all the way up. If after conducting the level test I find that one speaker is in fact louder than the other, if both are turned all the way up how can I compensate for the difference? Should I not need to turn one of them down to make them equal?

[29CountsNY]

Every video, article, conversation I have had about studio monitor calibration, I have always been told to use the C Weighting and put the meter on slow, not fast.
I would use the noise generator in Pro Tools to generate the pink noise, that way you are eliminating anything from the chain but the tone generator and the speakers.
If one speaker is louder than the other when you have the volume knobs on the back of the speakers all the way up then I would use the lower volume speaker as the starting point and turn down the other one so it matches the lower one in volume.
Check out this YouTube video, its a little wordy and he is using S1 but the concept is the same.

https://www.youtube.com/watch?v=EZu2UZqdgDE

Also, here is a link with step by step instructions you can try:
http://deviantnoise.com/setup-studio-monitors-best-way/

[Terry Wetzel]

Hey Wireline. Thanks. I have some questions on your very helpful response. 1). Where might I find this source you speak of, (I.E.),(Balanced on the stereo field and across the audio spectrum)? 2). I'm on a pc. how do I find out if my sound card is out of balance? Left Right Lock? I'm not familiar with that terminology. 3). By make sure the connections from the sound card are perfect, in my case they don't come from the sound card. They come from the back of my 2i4 I/O to the speakers. Again, I'm not trying to be contrary, I'm just trying to make sure we are speaking the same language. I haven't been able to afford room treatment yet but I know it will help. Thank you again.

[Terry Wetzel]

Thanks. Very informative video. I'm not sure that Pro tools 9 includes the Pink Noise signal generator ap. (?). I'm considering switching to Studio One. As to the Meter settings, fast/slow A or C weighting I guess it depends on who composed the reading material. So, you are positive that it's C and Slow? I'll try both out of curiosity. Thanks again.

[29CountsNY]

re: C weight and slow settings.........10000000% positive.

[Darryl Ramm]

Uh oh well another DUC thread off and running and not a lot of sanity check applied.

Tiny little LSR305 monitors. 85 dbSPL? Cough. Why? Maybe think 79db SPL. If you want to calibrate to a level at all.

Untreated room: well that's an intersting problem. Not ours.

Advice to turn up any monitor all the way for anything: uh Dear God no!

First sanity test: if you think you hear a problem just try swapping the actual powered monitors with each other and see if the perception of one being louder or not moves. Swap/don't swap the monitor lead connections as well for bonus points.

Calibrating SPL levels may be useful, but maybe not if it moves a listening level you are already comfortable with. You can always pink nose and equalize loudness on both monitors at whatever SPL you want if that solves a problem for you. With small monitors especially that you can't drive very hard you need to listen to what levels reference material sounds best at and don't stray too far from there.

You can Google "calibrate studio monitors" and get a wealth of information online, precise instructions etc., that question itself really does not need another thread on DUC.

Messing around worrying about with this stuff too much in a room that needs treatment (we cannot guess how much that applies here) can be a waste of time. Get any gross audio problems with the room dealt with.

[29CountsNY]

Originally Posted by Darryl Ramm

Uh oh well another DUC thread off and running and not a lot of sanity check applied.

Tiny little LSR305 monitors. 85 dbSPL? Cough. Why? Maybe think 79db SPL. If you want to calibrate to a level at all.

Untreated room: well that's an intersting problem. Not ours.

Advice to turn up any monitor all the way for anything: uh Dear God no!

First sanity test: if you think you hear a problem just try swapping the actual powered monitors with each other and see if the perception of one being louder or not moves. Swap/don't swap the monitor lead connections as well for bonus points.

Calibrating SPL levels may be useful, but maybe not if it moves a listening level you are already comfortable with. You can always pink nose and equalize loudness on both monitors at whatever SPL you want if that solves a problem for you. With small monitors especially that you can't drive very hard you need to listen to what levels reference material sounds best at and don't stray too far from there.

You can Google "calibrate studio monitors" and get a wealth of information online, precise instructions etc., that question itself really does not need another thread on DUC.

Messing around worrying about with this stuff too much in a room that needs treatment (we cannot guess how much that applies here) can be a waste of time. Get any gross audio problems with the room dealt with.

Good luck Terry, I am out!