[awesomebase]

Originally Posted by got wake?

it is best to not try and correct someone unless you are 100% sure you are correct decibels are logarithmic, so a 10 dB increase = twice the volume. but what do i know, i've only competed in stereo competitions since i was 16 (11 years now) and was an IASCA judge for several years as well





that is correct. a 3 dB increase could require the same power with double the drivers (in reference to speakers). speaking from a subwoofer perspective, if you where to double the number of subs and doubled the power supply (second amp, or an amp that is twice as powerful), it equates to about a 6 dB increase. however, those are only generalizations. the higher you go, the harder it is to increase the loudness/dB's, since it is not perfectly linear.

Well, I thought the whole point of boards was to share information -- if everyone already knew everything, than there would be no point in having these discussions. So, with that, I'm not picking on anybody, and certainly not trying to pick a fight, but in the spirit of a good discussion, I gotta say that anybody that knows anything about speaker building and getting a nice flat response from their crossovers knows that it is pretty much accepted that a 3dB increase/decrease means double the volume. Look at charts from even the pros and you'll see that they all strive for a flat response for a well-balanced speaker -- usually nothing more than 1 or 2 dBs difference across the entire spectrum (in a 2 or 3 way speaker) for anything resembling a professional product.

I'm not going to debate whether this is applicable to horns or not, but people should know at least what is accepted as industry standard. Even the SPL meter did its job and made the point. All I'm saying is that whether or not you "feel" like its double the volume, a 3dB increase is considered as such. This will avoid a lot of confusion when you talk with others about more important things like your truck's speakers and amplifiers.

Your subwoofer example is greatly simplified... you're not saying whether the subwoofers are independent arrangements, connected in series or in parallel and how that affects your resistance and power requirements from your amplifier (i.e. ~ 1,2,4, or 8 ohms depending on, again, your arrangement). But I do get your point. I'm just saying, our ears may not confirm what tools designed for this purpose confirm. Two independent horns should be 3dB greater than one and that was confirmed. It may not "feel" like that to us, but much like an earthquake, a 3.6 (on the Richter scale) doesn't feel like it is double the power of a 3.5 earthquake, but it is. I'm not a retail custom-speaker designer and I don't do SPL competitions as I prefer quality of sound, not quantity. Don't take my word for it though, check out Wikipedia or get on the boards at audioholics and make your case (I've been there for 8 years now).