Originally Posted by AFF
I am not planning on anything too drastic really. But I do have 2 G12T-75's and I need two more speakers for replacing factory crate speakers. I like the wizard mixed with the 75's and I like some of the sounds of the Vintage 30's mixed with them.
I always keep my eye on impedence ... it's the quickest way to kill an amp or speaker.
I was more worried about speakers over powering each other in a half back cab (half sealed-half open back). As soon as I get some replacements I will post my findings.
If you have any more info please post away.
A lot of people laugh when I try new things but I always come out happy with my result. A lot of what people consider normal was thought of as rediculous at some point in time.
All speakers have a rating called sensitivity. This is measured in dB SPL, @ 1 watt, 1 meter, usually a 1 kHz sine wave or pink noise, I can't recall.
Either way, here's how to use that info:
Every ten decibels more is double the perceived loudness (phons).
Every ten decibels less is half the loudness.
So, if two speakers have sensitivity ratings of 96 and 99, they're going to sound very close. If they have ratings of 89 and 103, then one will sound more than twice as loud as the next.
Phons are ratings of perceived loudness. Because phons are not even, we must then measure them on a more complex scale, called the Fletcher-Munsen curve. They are equal to 1 dB @ 1 kHz. 100 phons, for example, is 120 dB @ 30 Hz, 100 dB @ 1 kHz, and 86 dB @ 4 kHz. 80 phons is 77 dB @ 500 Hz, 84 dB @ 10 kHz, etc.
You can estimate how loud a speaker will sound with some regularity using this scale and the frequency of the test wave, but don't worry about doing it, however, it's far too complex to worry about. This part of the post is really more for reference, as some may be interested.