T'byrd,
You want opinions? Oh boy..... hello, can of worms!
The major problem in making assumptions like yours is common, so don't worry, no one's getting on your case here. (You need to have at least 10 or 12 posts before we start in on you.
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The original intent of Leo's vision was as Chris noted, there's just "something" about that much paper cone moving so much air, and from an open back cab. But we have to remember the time at which that first took place, and the environment surrounding those circumstances.
1) Volume levels were much lower in those days.
2) Venues tended to be smaller than arenas, think roadhouse here.
3) Many venues were much more barren of decoration. Bare walls and hard tables and chairs were the order of the day (cheaper to replace after a barroom brawl). No soft stuff to soak up sound.
4) Most playing styles didn't think of the bass as an instrument with a player, it was more like "well, the sound is kinda empty without some kind of bass". Just enough to remove the feeling of "empty" was enough, in those days.
5) Technology was not quite up to snuff in those days. Thieleman hadn't yet formulated his parameters for how a speaker interfaces with the surrounding environment, so a raw speaker was pretty much just thrust into a job. If it survived, great; if it didn't, then they tried something else until they found one that did survive. What I'm saying here is that Leo just chose a speaker based on it's manufacturer's ratings. If he tried several (and he did), and found more than one that he liked, then it boiled down to how much the thing cost in 1000-unit lots. Not very scientific, I'm sure you'll agree, but that's the way business was done in those days.
Back to your premise......
In today's more knowledgeable world, we know that if we push a speaker cone too far (the excursion distance), it will distort, and possibly self-destruct. We also know how to build a voice coil so that it doesn't overheat and melt when being punished by kilowatts of energy. More to the point, we can use some parts to build similar-looking items such as 10" speakers, but make them sound entirely different. While you can buy a 10" speaker from, say, Jensen, you can
not just blindly assume that any old 10" Jensen speaker will work well for either guitar or bass, there's now a world of differences built into speakers made for those two very different purposes.
This concludes the lecture portion for today. Let us now relax, kick back, and shoot the breeze.
I would not use any open back cab for bass, no matter what the speaker complement. Experience, if not good common sense, tells me two things:
a) Low frequencies have very long waveforms. Sound coming out of the back of an open back cab will reflect off whatever is behind said cab, and those reflections will merge with whatever came out the front. At any volume level above normal speech, this combination tends to get very mushy (flabby, muddy, your choice).
b) While a bass is meant to be used in the bottom region of the sound spectrum, there is a certain amount of energy in the mid and high regions that needs to be reproduced as well. One speaker can't do justice to the entire range, so a modern, well designed cabinet with a smaller speaker and a cross-over will tend to deliver better overall tone than one or more single size speakers.
Experience has also taught me some other things, not directly related, but close to my heart:
i) I can no longer lift and carry monster boxes - smaller is my friend. ;D
ii) I can no longer afford to emulate my heroes of yesterday - modern is cost effective (collectors aren't driving prices into the stratosphere).
iii) Old ears can detect distortion much,
much more easily. Speakers that have been mistreated, are worn out, and/or were cheap to begin with, none of these sound very good to me. In fact, they are usually intolerable, and I either put in my ear plugs, or I leave the premises. Call it old fart's disease, but hey, they're my ears, and Gawd isn't gonna issue me a new set anytime soon. ;D
iv) Sometimes you just have to compromise. There's a time to double up on something, and there's a time to put your foot down, and just refuse to accept second best. The ability to recognize when to do each of those is something that comes only with experience. When making a tough choice about what to buy, or what to take to a gig, listen to your heart as well as your head, and you'll likely come out all right.
But trust me on that part about the sunscreen!
HTH
sumgai
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