Since it is a genuine question I'll give you a detailed example of the time-line on the SA-8 :
First run... spent quite a bit of time from when I stopped making the E8 until launching this model. Went for a beefier motor and coil with a wider spider, etc... all things I wanted from experience the E8. All testing in house was great -- no problems at all in our testing at any power level we imagined anybody would use. I had assembled the prototypes myself from raw parts to try several different parts variation.
Released them to the public at this point but but in production found that the production glue on the spider landing wasn't as strong as mine ; so in larger than suggested boxes or at high power some folks would pop them off the landing -- so I made the video for adding epoxy to the landing. Most folks that bought the first run were forum users so very limited issues.
So the next run I added the spider bolt down ring -- then one of my SPL guys using them in a wall was tearing surrounds as his box built so much internal pressure compared to any testing I had done with 1, 2, or 4 drivers. We have yet to tear a surround in Sean's CRX doing 150s from the single SA-8 to this day... still the original surround mold. But in that application I saw room for improvement.
Tooled a new surround to address an issue for maybe 1% of potential customers then released them again covering any failures I had seen so far.
I noticed that any failures now with the new surround and bolted on spider were due to burnt or snapped lead wires -- now that the spider could not come unglued regardless of abuse levels it could be stretched and the tied on leads would snap as they don't like to stretch like fabric is capable of. Also some folks that were running smaller amps and clipping the crap out of them were simply burning the leads up. The leads we used are more than adequate for 400-watts... in fact, back to the 150+ CRX... still using original leads with 100s of 2kw burps.
So I tested a few spider variations with different rolls to reduce lead stress and also increased the lead size by about 50% to the same size as the SA-10s/12s/15s to address this last point of potential failure. By this point we've got 100s and 100s of SA-8s out there and honestly the % with lead breakage was still quite small -- but if one person breaks my speaker I want to make it stronger at that point -- it's just how I am.
Now here we are at the current model -- so far no damaged drivers at all from this run for any reason. They all now have the bolt down ring, the new surround, the new spider, and the larger leads wires. All things that in my initial testing never showed any need for improvement.
Now -- based on the 100+ hours we have in Sean's CRX testing SPL I think I can improve it more... so the v.2 is in development. It is a v.2 as it will no longer be compatible with older units as it is changing quite a bit. We filled up 4-5 sheets of paper last week doing testing at different power levels and frequencies -- suffice to say lots and lots more R&D is going into the SA-8 v.2 -- but chances are I'll eventually figure out a way to make that better too //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif