Re: [ARSCLIST] headphones "break-in"?

[Scott Phillips <scottp@xxxxxxxxxxxxxxxxxxx>]

I have reconed large woofers used in studios for years, never done a bad
recone. I always test for the resonate point of the driver with an
oscillator and amp. This point of resonance changes with the amount of
use the driver sees, going up in frequency as the woofer nears its final
'wooffing', so to speak. This effect is much more pronounced with very
large paper cones on 12" through 18" woofers, and seems very slight on
drivers with high-tech materials in them. HF drivers, it seems to be
only an issue (and a slight one) on compression drivers, and this seems
IMHO to be a complete non-issue on normal audiophile sorts of speakers.
In massive PA systems, that is a bit different. Materials are much
better than they used to be. Sure, there are audible differences as
speakers age and the materials develop excessive flexing from long or
destructive use.... But I don't see this as a positive development. Any
manufacturer that is worth anything wants the materials to change shape
or characteristics as little as possible for as long as possible. The
idea is for the cone to be as stiff as possible, and the foam (or other
surround material) is just there to keep the cone centered in the basket
and provide a consistent return to a natural resting position. All the
flexing is there. Since on some paper coned woofers that surround
material is just treated cardboard really, they will change quite a bit
in flexibility over their useful life, but again this isn't a good thing
on the whole. I suppose since the enclosure is partly designed around
the resonate point of the woofer, one could figure out where the driver
would 'change' to as it aged, but personally my experience with them was
that this point stayed in a pretty narrow area until just before the
driver went bad.

Just my two cents, of course.... I couldn't say for headphones, but I
think for audiophile type speakers made within the last 10 years or so
this is just a non event. Old habits die hard. 

Scott

-----Original Message-----
From: Association for Recorded Sound Discussion List
[mailto:ARSCLIST@xxxxxxx] On Behalf Of Marcos Sueiro Bal
Sent: Wednesday, December 19, 2007 8:24 AM
To: ARSCLIST@xxxxxxxxxxxxxxxx
Subject: Re: [ARSCLIST] headphones "break-in"?

I don't understand --I thought you wanted your speaker cones as stiff as
possible, and the gasket as flexible as possible; this is precisely why
today they use cone materials such as Kevlar or (gasp!) aluminium.

I often hear of improvements to audio equipment after break-in periods
and, I must say, I need to see hard science on this. It would be
interesting to test frequency and transient response of a new speaker or
headphone driver versus one that has been "broken-in".

An even easier experiment would be to "exercise" only one side of the
headphones for a few hours, and then play a mono recording (such as an
early-recording Living Presence CD ;-)), and see if you can tell the
difference when you flip the drivers (or even before) (assuming
"symmetrical" headphones).

Tom, would you volunteer for such an experiment and report to the list?

Marcos

Tom Fine wrote:
> Hi Bob:
>
> I tend to agree with you except that some newer speakers have drivers 
> made of such stiff material that they actually do SOUND better after 
> they get flexed a little bit. I doubt many if any speakers made today 
> have the old paper cone material on woofers, for instance. Some 
> high-end audiophoolishly-priced speakers claimed to come "broken in"
> from hours of loud playing at the factory. Remember that some of these

> modern woofers have cones made of metal films, certainly a long way 
> from "egg carton" paper.
>
> The same is true in some respects of modern headphones -- the drivers 
> are made of relatively stiff materials that may not flex optimally 
> right out of the box. In any case, I figure it can't hurt to run the 
> cans with the junkola super-compressed FM rock station all day and see

> if I hear a difference with better music at lower levels tonight. I'm 
> not running them anywhere their rated break-up point right now, just 
> louder than I like to listen.
>
> As for the foam thing, I remember watching the foam surround on a 
> friend's older Infinity speakers literally blow apart from loud music 
> at a party. Some of the older types of foam get brittle and flakey 
> from exposure to either air or moisture or heat or all and then they 
> disintegrate from the flexing of the woofer. Without the foam to damp 
> the woofer edges, it sounds awful and I think some speakers can then 
> over-drive the piston to where the speaker is broken.
>
> -- Tom Fine
>
> ----- Original Message ----- From: "Robert J Hodge" <rjhodge@xxxxxxx>
> To: <ARSCLIST@xxxxxxxxxxxxxxxx>
> Sent: Wednesday, December 19, 2007 9:29 AM
> Subject: Re: [ARSCLIST] headphones "break-in"?
>
>
> Sounds like audiophoolery. Do speakers need a break in period? I don't

> believe so. Unless you're addressing a foamed surround in which case 
> the break in period ends when the foam breaks down and they need to be

> re-edged.
>
> Partially kidding..
>
> BH
>
> -----Original Message-----
> From: Association for Recorded Sound Discussion List 
> [mailto:ARSCLIST@xxxxxxx] On Behalf Of Tom Fine
> Sent: Wednesday, December 19, 2007 9:14 AM
> To: ARSCLIST@xxxxxxxxxxxx
> Subject: [ARSCLIST] headphones "break-in"?
>
> Hi All:
>
> Do professional headphones work optimally if one allows a "break-in"
> period or is this
> audiophoolery? I don't know enough about headphone driver design to 
> know if a new pair benefits from playing relatively loud radio content

> or pink noise for a few hours to loosen up the mechanics.
> Based on the fact that I listen to headphones at ear-healthy low 
> levels, this "break-in" would probably be as much "exercise" as the 
> drivers would get, but if they are indeed "stiff" when new, it might 
> be beneficial, too, for low-level listening (ie potential better 
> dynamics response, better sensitivity for low-level bass, etc)??
>
> -- Tom Fine