Re: 4 July Hi-Fi
To be totally honest, I do not remember when the original measurements/spec sheet were made-in relation to when the TH118 started being built. I can check/cross reference jobs etc-but it won't happen soon-as were are extremely busy over the next several weeks with some really important "stuff/projects" going on.
It is HIGHLY likely that the spec sheet was of the B&C driver-not the 18 sound. Rarely do we have a spec sheet at the time a product starts shipping. There are many people "in the know" who get/use products long before the spec sheet hits the streets (this is how we first found the issue with the 18 sound drivers). Not that many cabinets went out with the 18 sound drivers before we discovered a problem-luckily I was the one who found it on an install that baffled me for awhile. Then further testing in the shop with one of the defective drivers showed me what was going on. Other 18Sound drivers were just fine-as we had used in our initial testing of the product.
Early on is when we noticed the issues with SOME of the 18 sound drivers. Not all of them had the problem-so we replaced all the ones that had an issue.
I remember when swapping out drivers in the exact same physical cabinet and using the same measurement position (eliminating as many variables as possible) that the differences between the drivers was extremely minimal at best (we are talking 1/4 to 1/2 dB type stuff here-if I remember correctly). So as I stated earlier the CABINET is the biggest contributor to the overall response-the drivers are simply "pistons" pushing air.
Personally I would be a lot more concerned with manufacturers who do not provide any data or measurements or whose products can't come with within 10-15dB of stated specs. or whose "simple numbers" are 6-10dB off from their measured graphs-or whose prediction data has been greatly modified so that it doesn't show the "bad stuff" etc.
But maybe that is just me. EVERYBODY should be held to the same level/expectations-and not "given a free pass" just because of who they are.
Yes we want to be as accurate as possible-but you also have to consider driver to driver (of the same model number) variance. That can account for a dB or two in some cases. When we do a measurement-it is of a random cabinet-NOT picking through a bunch to find the best one. So the actual measurement could look a bit different (once you get down to that level) of the same model number.
Yes the data name details was changed on the response curve. That was in accordance with what YOU pointed out in the earlier thread-about watts vs volts. So I simply changed that part (as per your request) and the new date popped up.
I have yet to hear from anybody who says that the TH118 (or any of our products) are not performing as the spec sheet says.
