How "loud" is that amp?

[Phil O'Keefe]

One thing that's missing, though is frequency response. Most players specifically choose a speaker vs. another one specifically for it's non-linear characteristics. Certain frequencies sound louder than others. To use the obvious example, if the mids are too scooped, the sound disappears -whether it's done by a graphic EQ or a speaker.

 

I think I addressed the Fletcher-Munson curve a bit earlier in the thread.

[Kap'n]

OK, so I'm stupid.

[Phil O'Keefe]

OK, so I'm stupid.

 

Not stupid - you just didn't see it.

[orourke]

Excellent questions! Originally, less efficient speakers with relatively low power handling capability were utilized in guitar amps because that was all that was readily available. Over time, more efficient designs were made; speakers with higher sensitivity, greater power handling capacity, and wider frequency response... but they tend to cost and weigh more. Also, tonal considerations come into the equation. A more efficient speaker may - or may not - be to your liking. Guitarists are fairly finicky and conservative traditionalists in terms of their gear. AlNiCo speakers (that utilize AlNiCo magnets) are still favored by some, even though rare earth magnet materials (neodymium, samarium cobalt, etc.) are stronger and more efficient. Ceramic magnets are often utilized because of their relatively low cost... it's always a trade off in terms of weight, cost and performance... and sound. Remember, "speaker breakup" and other tonal contributions from the speaker may be considered beneficial, even though they are the antithesis of "accurate". The E/V 12F (a 12L variant made for Fender) in my Princeton Reverb II has 200W RMS power handling capability, is highly efficient and loud as hell (~101 - 103 dB @ 1W / 1m), but it doesn't even began to strain or break up under the influence of that little 20-22W amp. It has a huge, open and big bottomed sound to it, and sounds completely different than the 15W Weber Blue Dog in my AC15, which not only has different frequency response characteristics, but also strains and distorts when pushed. It's not "better" (except in terms of power handling capacity and efficiency) or worse, just "different". Sometimes we guitarists want that tonal contribution from the speaker. A Celestion Greenback breaking up has a distinctive sound to it, and it contributes positively to the sound of a wide open Marshall. A Blue is closely associated with the classic "Vox sound", just as the old Fender Jensens are the voice of old Blackface amps. Also, wide range frequency response is not always desirable in a guitar amp and speaker. We LIKE that bandpassed sound, with nothing much going on above 5-6kHz or so... run a guitar direct into a mixing board, and you hear all that high end (stuff above 6kHz) that guitar speakers naturally roll off. Bass players love it, as do keyboardists, but guitarists? We WANT low-fidelity. That's why you'll find crossovers and multiple drivers (including horns) in keyboard and bass amps, but almost never in an electric guitar amp.

^^^^ This is the best part, good info in there (should have put it in the HC Confidential article).

I've been struggling with some of this stuff. I'm getting older, doing dive bar gigs, but still want to run stereo rigs. I get me dirt from pedals, so I like plenty of clean headroom. But there's they weight of my rig to consider. Lately I've been using a Reverend Hellhound 4x10 cab with either a Mesa Mark IV running at 20 watts or the Hellhound Head running at 60w and a Vox Night Train 15w head with a Mesa closed back Theile 1x12. This rig sounds great in smaller bars when I don't have to get too loud, but the open back Reverend predictably starts farting out in bigger rooms, especially when I'm using my baritone.

Sometimes I think about selling off the Reverend, but of course there's the money issue.... this stuff gets really complicated.