Monitor "Break-In"

[Zetajazz44]

I bought a set of M-Audio BX8a's yesterday...

I've read on this forum somewhere, although I couldn't find it with a search, about 'breaking in' monitors... Something to do with playing a 'sweeping' sound frequency through them for a few days or so...

If anyone can elaborate on this it would be much appreciated.

Thanks in advance,

[reshp1]

You accomplish the same thing by playing music through them for a period of time. It might take a little longer, but no one wants to hear a sweeping sine wave for 2 days.

[scrubs]

I think Harvey Gerst (who used to design speakers) said that modern speaker materials do not really benefit much from "breaking in." Older speakers were made from much stiffer material that may become more flexible (thus increasing bass response) over time. Newer materials are already flexible and do not change much with playing. Personally, I think your ears just get used to the way the speakers sound over time (same with headphones, where audiophiles will claim you have to "burn them in" by playing music through them - hogwash, imo). If you're that worried about it, just play some music at a moderate volume for 24-48 hours and see if you notice a difference.

[Zetajazz44]

Originally Posted by reshp1

You accomplish the same thing by playing music through them for a period of time. It might take a little longer, but no one wants to hear a sweeping sine wave for 2 days.

Good deal... That's what I'd heard: "Sweeping Sine Wave"... My studio is not part of my house and is actually very isolated, on it's own lot, in the middle of nowhere... far away from anything else... I see you are a ProTools guy as well... If I wanted to use the sweeping sine wave method, is there something in ProTools I can set up to do this?

Thanks,

[Harvey Gerst]

Scrubs has it exactly right. If the diaphragm of the speaker is paper, running the speaker for a few days playing songs with lots of low frequency content can lower the resonance of the speaker and extend the bottom end. If the speaker has a rubber or foam surround, it ain't gonna change very much.

[Zetajazz44]

Originally Posted by Harvey Gerst

Scrubs has it exactly right. If the diaphragm of the speaker is paper, running the speaker for a few days playing songs with lots of low frequency content can lower the resonance of the speaker and extend the bottom end. If the speaker has a rubber or foam surround, it ain't gonna change very much.

Thanks Harvey,

The BX8a's I have are the latter... So I should be able to just plug them in and start using them... That's fine with me...

Thanks again,

[stevetat]

Originally Posted by Harvey Gerst

Scrubs has it exactly right. If the diaphragm of the speaker is paper, running the speaker for a few days playing songs with lots of low frequency content can lower the resonance of the speaker and extend the bottom end. If the speaker has a rubber or foam surround, it ain't gonna change very much.

The dominant compliance (stiffness) in a woofer is its spider (damper). The spider is typically a cotton, poly cotton blend or aramid (Conex, Nomex) impregnated with a phenolic. The density of the fabric's weave, amount of phenolic impregnation and geometry of the spider (number of rolls from the ID to the OD) all combine to determine the overall stiffness. During the break in period, the compliance of the spider changes as the phenolic and weave break down and relax, which lowers the resonant frequency of the driver.

If you want to read a little more about spiders, here's a link to an article I co-authored on the topic which was published in Voice Coil magazine back in 2004.

Spider Article

As for break-in itself, I've always favored pink noise. It provides a good, broad-band stimulus and you can null a lot of the LF output during break in by placing the monitors face to face with poliarty reversed.

[Theros]

The dominant compliance (stiffness) in a woofer is its spider (damper). The spider is typically a cotton, poly cotton blend or aramid (Conex, Nomex) impregnated with a phenolic. The density of the fabric's weave, amount of phenolic impregnation and geometry of the spider (number of rolls from the ID to the OD) all combine to determine the overall stiffness. During the break in period, the compliance of the spider changes as the phenolic and weave break down and relax, which lowers the resonant frequency of the driver.

Man, I just woke up... I think ima go back to bed now...

[Harvey Gerst]

Originally Posted by stevetat

The dominant compliance (stiffness) in a woofer is its spider (damper). The spider is typically a cotton, poly cotton blend or aramid (Conex, Nomex) impregnated with a phenolic. The density of the fabric's weave, amount of phenolic impregnation and geometry of the spider (number of rolls from the ID to the OD) all combine to determine the overall stiffness. During the break in period, the compliance of the spider changes as the phenolic and weave break down and relax, which lowers the resonant frequency of the driver.

That may well be true these days; I haven't kept up with technology as much as I should. In the past, it was usually the stiffness of the paper surround which governed the resonant frequency. I can see where the spider might now be a major factor with the advent of foam and butyl rubber surrounds (which don't change near as much with age as the one piece paper cone surrounds).

[Zetajazz44]

A little off the starting topic of this thread, but something I learned/found out after hooking these monitors up:

After reading another post on this forum about an SPL meter from Radio Shack to get the same volume from both monitors, I bought one just before I bought these monitors... I used the guage on these monitors and was quite amazed that according to the volume knob on the backs, one monitor had to have it's knob turned up almost 1/8 of a turn higher, which by the guage was about 4Db, to achieve the same volume level as the other...to balance them out... Listening to them, they sound balanced now...

[reshp1]

Originally Posted by Zetajazz44

Good deal... That's what I'd heard: "Sweeping Sine Wave"... My studio is not part of my house and is actually very isolated, on it's own lot, in the middle of nowhere... far away from anything else... I see you are a ProTools guy as well... If I wanted to use the sweeping sine wave method, is there something in ProTools I can set up to do this?

Thanks,

Hey, sorry I kinda forgot about this thread. If you're still interested, off the top of my head the best way I can think of to do this in Protools is to insert a signal generator on a track, automation enable the frequency parameter on it and use the pencil tool to draw a diagonal sweep up and a diagonal sweep down in the edit window. Highlight this section with the selector tool and set the "play" button in the transport window to loop this selection continously. Then get the hell out of that room because it'll give you a headache in about 5 seconds.

[sushi-mon]

Originally Posted by Zetajazz44

A little off the starting topic of this thread, but something I learned/found out after hooking these monitors up:

After reading another post on this forum about an SPL meter from Radio Shack to get the same volume from both monitors, I bought one just before I bought these monitors... I used the guage on these monitors and was quite amazed that according to the volume knob on the backs, one monitor had to have it's knob turned up almost 1/8 of a turn higher, which by the guage was about 4Db, to achieve the same volume level as the other...to balance them out... Listening to them, they sound balanced now...

I wrote that thread and I am glad you had the same experience I did after getting the SPL meter. I also still use it to see what level I am monitoring at as well.

I was listening to some recordings last night, and the left channel was up about 1-2 db, and I could hear that the left side of the stereo field was up as well. Feels good to know I have my monitors balanced !

P.S. I would also hesitate to leave my monitors and ProTools on for any extended period of time without supervision. I would just worry about something going wrong and maybe frying a monitor.

My advice about burning your monitors in, is to just make sure you keep listening to CDs through them. Get to know your monitors by checking out all your favorite stuff on them. This is a good use of time, instead of worrying so much about burning them in artificially. A lot of times, I just sit down and listen to a new or old album instead of doing anything else.

Plus you are developing your ear, and finding out what your likes and dislikes are about certain pro recorded material. This will all help you make better mixes down the road by taking time to listen to what your monitors sound like on well mixed material.