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Agreed, I wasn't disputing this, simply saying most people think you need to "take it easy" on a sub woofer right out of the box. When that simply isn't needed

Per Vance Dickason in The Loudspeaker Design Cookbook, the following are measured parameters for a 6.5" Peerless woofer; Pre-Break In (i.e. out of the box) Fs: 49.9hz Qms: 2.11 Qes: 0.44 Qts: 0.37 Vas: 16.8L Post-Break In (12hrs @ 25hz, unspecified power) Fs: 44.5hz Qms: 1.97 Qes: 0.39 Qts: 0.33 Vas: 21.6L However, enclosure requirements/performance will be nearly identical since the Fs/Qts ratio stays virtually the same even though there's a decent % variance in some of the parameters. On that point, published T/S parameters are either taken from a single driver or an average from a sample batch. The actual T/S parameters for two different drivers from the same product line can vary by as much as 10% or more (I believe most manufacturers consider a variation of 10% to be within tolerance), some have a significant difference in T/S parameters if QC is poor. So really, the difference in pre- and post-break in T/S aren't any greater than one might experience between two drivers as a result of production variances. Is "break in" a myth? No, not really. As indicated, you can clearly and easily show a measurable difference in parameters. Is there going to be a readily apparent audible difference? With your typical driver....probably not. The resultant changes in response are going to be virtually inaudible. On a high powered SPL sub with a ridiculously stiff suspension routinely driven to it's mechanical limits, results may be a little different. The variance would probably be enough for a meter to pick up (tenths of a decibel), so it may matter in that particular arena. Do you need to ascribe a particular time period for "break-in"? No. Just plug it in and play it like you normally would. If you really want to break in your driver, playing it at a low level for some arbitrary time period is counterproductive. The best way to effectively break in a driver is to play it free air at a high excursion level for a couple hours. It will be sufficiently "broken in" after that.

most people refer to this like a car engine, how you need to take it easy on the engine for the first "3000" miles, this is true for engines, subwoofers....no. When a sub is new the suspension is at its stiffest, we say, beat the hell out of it right out of the box. Remember, it's not an engine

Somewhat spur of the moment, this sub was made as a “what if”. We already have the magnets and magnetizing fixture for them, so we figured a way to integrate them into a car audio application that seemingly solves a good portion of the issues associated with neo. The TS params are somewhat inconsequential compared to thermal stability. We can always tweak soft parts, geometry, and magnet sizes/grades to get those. We ran some 3d FEA modeling of it and it came up as a little overkill for what we could flow through a standard core, but figured it would be a solid platform to test some different cooling techniques from. We are going to start running some long term thermal tests on it to make sure that the cooling is up to par to ensure long term thermal stability with a standard grade neo magnet. Issue is this… while there are higher thermal grades of magnets, the price seems to go up exponentially for similar strength. So… if we can keep a standard grade magnet cool and working below Tmax during a Las Vegas summer and at high power, it will help reduce the overall cost of something like this. Nick will spend some time next week adding some thermocouplers to another one we are machining and test it at various points, frequencies, excursion and power levels to see how effective things are at not just cooling the coil, but the thermal mass as well. Once we get a solid baseline with this one we can go from there. Point of posting pics was to gage interest in something that was a fair amount out of the ordinary. No sense in going down a path for a new product line if the target market isn’t the least bit interested in how it looks. For noise control/industrial applications aesthetics normally take a back seat to function. For autosound we have to find a balance as the flame baskets still do dominate the world of sales

I'd spend some time listening with the sub off as well. Try and re-create the problem that took them out without getting to that level. I think you'll be surprised at what you hear without the sub. I don't disagree at all with Brad's suggestion, but I'd always first play with what I have and REALLY determine what is missing before making any change. On top of that if you are thermally wasting those drivers then your idea and mine of reference levels are a bit apart

Why the fascination with BL? It's simply a means to an end. Higher isn't better, lower isn't worse, as long as the overall design goals for the driver were met. XBL itself, as a motor topology, really has nothing to do with frequency response, so the statement "but stays flat inbetwen due to XBL" really doesn't make any sense. You can build low inductance drivers with XBL and you can build low inductance drivers with other topologies or motor designs.

He actually posted that question on this forum aswell Link here:

This is a great link to add to the discussion of BL and Bl curves. http://www.soundsolutionsaudio.com/forum/topic/9421-an-unbiased-comparison-of-linear-bl-technologies/

got board and decided i needed some better wire management so hears how it came out. also the dog came to watch me.

ran my power wire to day. what wire i have left. hoping its enough to redo my big 3

more packages came in he he he. ups must hate me old wire.......... any one want it? had to lube up the new wire. i need to learn how to cut wire.

Sexy Scott! Have you ever thought that you might be Midas? Because it seems like everything you touch, turns into absolute gold!

get off my balls? don't call me a troll krill. his projects are full of fail. constructive criticism? okay. that is one of the ugliest cars i have ever seen. junk it. then look through the forums and find out how to a proper build