After reading that quality speakers require ripening period to get the best...............really?????? Where do you get this from??? Seriously, where would you get the idea that electronics ripen with age???? Enlighten me, please
As my brother explained to me:
The run in period for a speaker is largely dependent on it's suspension type + materials. You also need to consider the excursion, but for a system, you probably are not given that info-
When I do final voicing on a system, I normally have a set of drivers to chose from to build the system that meet certain service limits (response, TS and impedance limits). These measurements are taken from drivers that are fresh from the sample or line build and have to be broken in afterwards- otherwise, I am voicing a system that I know for a fact will change.
What changes??
Resonance related parameters are the ones that change the most. When looking at a very low compliance mid-woofer for instance, you may see a significant shift in the overall compliance factors of the model. In general, the speaker will get "warmer" as it breaks in; largely due to the Cms and Qms changes as the suspension breaks in.
What breaks in? Well, the suspension is mainly the damper (spider) and is generally a fabric of some sort with a phenolic impregnation that is formed under a clamped, high temp environment. This is notably stiffer at first deflection and to be honest, you can hear the things creaking, cracking and in general sounding like rice-crispies on the first deflection- particularly on larger woofers or very low thread count dampers. The break in there is generally rapid if you run the driver at or near Xmax. On a midbass or midrange driver, I normally use dedicated signal to run the driver in. Of late, I prefer to use a shaped tone burst at or around estimated Fo. Running this signal at or near Xmech will give you a very nice break in over the course of 45 minutes to an hour with bursts at about 3 to 5 second intervals. Incidentally, a lot of the better companies out there in the woofer business are starting to use shaped tone burst testing as an accelerated life test. 12 to 16 hours on a TBT at Xmech is tough on a woofer, particularly one that is a higher end model and has to really stroke to get the SPL that the customers demand.
Tweeters- My experience is that the tweeter or a dome mid (single suspension device with a very low x-max) will run in best with a composite signal such as white noise. I prefer a white signal as it is not filtered on the top end and gives me a little more content (heat) to soften the suspension and get the fluids balanced if the driver is fresh. These will run in faster- my experience is that 30 minutes at Pmax is more than plenty- I winder if 10 minutes would be adequate in some cases. Interestingly, many of the higher end tweeters typically run in faster- and most do not have any Ferro fluids in the gap which further reinforces the fluid mix / balance concept as part of the response settling out. This is only valid in the first few days of the tweeter assembly as I know it, but others may have different experience.
If you do not have test signals to use, then what- Someone mentioned using classical or jazz with a wide dynamic range. There you go. The nose that the engineer may use is a very wide range of signals all played simultaneously and that is the fast road to run in.
A word of caution though- do not hammer the crap out of the speaker or system during break in. You want to run it in to where the compliance model is settled out but not bash the VC into the bottom of the yoke. As the break in progresses, your compliance will be changing and 10 watts at a given frequency will drive the VC to the same level, but the compliance shift will let the mechanical parts move a greater distance. What is borderline bottoming out at the first of the test will likely be a big problem after an hour if you are running at or near Fo. Use common sense and know that if an hour with a signal does not do it, a few hours of moderate use or one hour more of jamming when the wife is out will do just fine.
With something like this, I encourage people to not bee to picky or get too worried about a break in. This is not like a car engine where you have metal on metal. The speaker has no interference parts that move and in general, you never want to have interference parts. Just do not go too crazy and if you ever hear bad stuff coming form the speaker, turn the volume down a notch.