Tone sweep for checking monitor EQ

[StevieC]

I've purchased a pair of M-Audio BX5a studio monitors and I'm in the process of getting them setup for what I hope will be a fun weekend of getting some recordings together.

Can anyone recommend a good site for downloading an MP3 that has a useful tone sweep so that I can check and adjust the EQ on these monitors as needed?

Also, what is this recommended break in period for a pair of small, powered monitors?

Thanks,

[FingerPlucked]

There's a break in period?

[StevieC]

Originally Posted by FingerPlucked

There's a break in period?

I would think so. I used to be into high end audio, and it wasn't unusual for a good set of speakers to have a break in period of 50-100 hours of "music time" at moderate volumes before the tone of the speakers started to smooth out. Prior to that, they would sound somewhat brittle and harsh. I"m assuming that the same would apply to powered speakers, but I'm wondering if the process or time is at all different since the amps are included w/in the speaker enclosures.

[Bob Womack]

Real Traps has a test tone CD downloadable HERE .

Bob

[Sunbreak]

Just be aware that you can't really EQ your monitors for a proper response. That takes room treatment--bass traps, first reflection points, etc.

The site Bob posted has tons of info about it--and probably an article or two about why you shouldn't do what you're about to do.

[StevieC]

Originally Posted by Sunbreak

Just be aware that you can't really EQ your monitors for a proper response. That takes room treatment--bass traps, first reflection points, etc.

The site Bob posted has tons of info about it--and probably an article or two about why you shouldn't do what you're about to do.

Thanks Cass (and Bob). I'll definitely check that site out.

So should the approach be to "trust" that the monitors are accurate/flat, and focus on adjusting the room until what I'm hearing/experiencing is flat rather than trying to adjust the speakers (which I suppose defeats the whole purpose)?

[3rd_harmonic]

I believe I have an app that can create a tone sweep. I haven't used it for awhile but if it becomes important to you and you can't find it elsewhere, PM me and I'll look on my hard drive.

[Sunbreak]

Originally Posted by StevieC

Thanks Cass (and Bob). I'll definitely check that site out.

So should the approach be to "trust" that the monitors are accurate/flat, and focus on adjusting the room until what I'm hearing/experiencing is flat rather than trying to adjust the speakers (which I suppose defeats the whole purpose)?

I would run the test tone while sitting in the mix position--it will tell you a lot. Every room I've ever been in needed bass traps--I'd expect to start there. Generally, it's more of a room problem than a monitor problem. Trying to EQ monitors for a flat response in any given room simply goes against physics. If you enjoy reading a little science, check out this article as to why it doesn't work.

http://www.acoustilog.com/eq_myth.html

Otherwise, Ethan's RealTrap's site will really tell you what it takes to get started. BTW, I've been down the 'compensate w/ EQ' road some years ago, lol.

A lot of people DIY, and that saves a lot of money.

Good luck!

[Doug Young]

Check out ETF: http://www.etfacoustic.com/ I found it very useful for tuning my room. I have a bunch of stuff on my web site about the process I went thru of treating my room, and trying to measure each step of the way that might be useful. it'd give you an idea what ETF can do, tho they also have very nice tutorials. Not free, but quite reasonable for what it does.

[Bob Womack]

Originally Posted by StevieC

Thanks Cass (and Bob). I'll definitely check that site out.
So should the approach be to "trust" that the monitors are accurate/flat, and focus on adjusting the room until what I'm hearing/experiencing is flat rather than trying to adjust the speakers (which I suppose defeats the whole purpose)?

There's not a simple answer, and there are two schools of thought on that issue. Be sure to check out my signature for info on where I stand on sweeping absolute statements.

Where to start? Hmmm... First off, many monitors come with adjustable crossovers to take care of any coarse adjustment needed once their are in place. They are there for a reason. They don't, however, take care of the stray resonances within the cabinets or the drivers themselves and they don't take care of the room nodes.

Quick answer: If the speakers in question are near-fields (to be set up above the mixer in the near-field), you may need to do nothing more than put up test tones or pink noise and tweak the crossovers. Past that, it's up to room treatment. However, if the speakers are eight feet away and are coupled to the room, you'll want to see what's happening in the room, adjust the crossovers to get things as flat as possible, and then adjust the room.

Longer response for the second case (far field or soffitted monitors) above: Once you get rid of the room nodes as much as possible by design or correction, if you've got the money, there's TEF (Time/Energy/Frequency) analysis to look at frequency response versus time plots. The deeper you go, the more there is to deal with. I'm sitting in a $75k Live End Dead End (unlicensed) control room (including custom DRPG diffusers designed by Peter D’Antonio) listening to $6k soffitted monitors with $4k worth of amps... and $2k worth of EQs. Now, mind you, the most severe EQ applied to the signal is a whopping 3-4db and it is not there to correct for the room but for the reproduction system itself.

My little professional home. Yes, that's my Svetlana Electron Devices mug in the foreground.

Bob

[StevieC]

Originally Posted by Bob Womack

I'm sitting in a $75k Live End Dead End (unlicensed) control room

That alone exceeds my total budget about about $74,500!

By the way Bob - I've always enjoyed your posts on the many threads that I've read, and I appreciate you chiming in on this one even though I'm clearly a novice in this area.

The monitors I've selected to get started with are set up in a "very" near field config (about 2-3 ft from my ears as I sit at the computer). My "studio" is a 6' by 9' space which opens at one end into a larger 12' by 20' space (both are part of a bonus room above our garage). I have an L shaped desk with my PC and monitors in the corner of the L.

I think I'll try to inexpensively tame any reflections that are coming from the wall behind me (and perhaps from behind the monitors). Apart from that, I'm not sure my budget will allow for anything much more dramatic. If you have any other ultra-cheap suggestions, I'd be glad to hear them.

Thanks again.

[Herb Hunter]

Originally Posted by StevieC

I would think so. I used to be into high end audio, and it wasn't unusual for a good set of speakers to have a break in period of 50-100 hours of "music time" at moderate volumes before the tone of the speakers started to smooth out. Prior to that, they would sound somewhat brittle and harsh. I"m assuming that the same would apply to powered speakers, but I'm wondering if the process or time is at all different since the amps are included w/in the speaker enclosures.

Several speakers that I have bought through the years came with signed frequency response graphs made as the speakers were tested prior to being packed for shipment. The speaker's frequency response was guaranteed to deviate no more than 1.5 dB from what was claimed in their brochure's specification page and the graphs were supplied as evidence that the speakers were within tolerance. If speakers needed to be broken in, the graphs would not be representative of the speaker's ultimate performance.

I do not believe that modern speakers need to be broken in and I've never seen any statement from a manufacturer that would indicate otherwise.

[Bob Womack]

Originally Posted by StevieC

By the way Bob - I've always enjoyed your posts on the many threads that I've read, and I appreciate you chiming in on this one even though I'm clearly a novice in this area.

My pleasure!

I think I'll try to inexpensively tame any reflections that are coming from the wall behind me (and perhaps from behind the monitors). Apart from that, I'm not sure my budget will allow for anything much more dramatic. If you have any other ultra-cheap suggestions, I'd be glad to hear them.

Thanks again.

Ultra cheap amd enlightening: Put a bookshelf full of books behind you at ear level as a diffuser.

Bob