The classic large JBLs come from two roots.
1) The 1930 Theater speakers were always used with _large_ multi-cell midrange horns, so only had to work up to 500Hz or even 300Hz, generally in bass-horns. These were just air-pumps. Because a 1,000 seat movie theater might have one or two 15-Watt amps, EFFICIENCY was vital. Cones were light, conical. No intention of treble but of course a paper cone is sure to radiate some mids. This is the Shearer System, several companies supplied these speakers, Lansing worked with one of them.
2) The ancestor of the D-130 was intended for smaller theaters or large studio. The "cone" is "curvilinear", a flared cone. This gives large area for bass but a stiff center for controlled treble. While all audio ideas are old, Lansing seems to have been the first to make good large curvilinear cones. The design goal was really just to get smooth response to around 1500KHz where it could crossover to a much smaller cheaper tweeter instead of the huge mid-horn and drivers. Again, efficiency was vital. The 130 is about the most efficient wideband "cone speaker" ever made.
All these vintage JBLs used coils from the one machine which milled round wire into tight flat wire at 4-inch diameter.
From those two you get variants. For bass-heavy work there is a copper-coil heavy-cone version which is half as efficient above 200Hz but has significantly more below 100Hz. The suspension can be loose for deep-bass when used in arrays with pre-controlled program; or stiff to resist abuse in stage amps. Dust-caps can be perforated, felt, paper, or aluminum. IMHO this is mostly about "looks", but they do give different highs. The aluminum center E-130 has good if ratty response all the way to 17KHz (only ON-axis). The soft perf center on the 2220 is falling at 800Hz and pretty dead above 2KHz. (But several beloved guitar-market speakers hardly reach 3KHz.) JBL changed magnet and clearance and I'm pretty sure the glue changed (perhaps before Gerst's time) to stand more heat. And there were 12" and 18" versions, again in several variants. But they all come from the mind of Lansing and all have very similar general tone, just a bit more or there to suit a specific market.
Any of the 120/130 will make more ear-smack per Watt than almost any other speaker. Some lesser speakers have more upper resonances and may "scream louder", but the big JBLs really make the most of the 150H-2KHz "body" register.
> marked 16 ohm but it reads much lower than that
Yes. The audio impedance is the DC resistance +plus+ actual work against the air (also some reactances). Most speakers are 1% efficient so the air-action is small. "16 ohms" will be 12 or 14 ohms DCR. The D-130 is 8% efficient at turning electric watts into watts in air, and that starts to show as a significant increase of impedance in the audio band.
> what the 130A is rated for(watts)?
I put many hours on E-130s with 180 watt tube amps, mostly PA mix. Loud but not abusive. Some pretty big crowds.
If you want LOTS of WATTS, go for the Electro-Voice EVM. Gerst talks of playing instruments to rate the power; E-V developed the standardized tests which are now (with mods) widely used to rate speakers. E-V 12L or 15L will take a steady 150 Watts anywhere in the guitar range, or 300 Watts highly clipped random noise, ALL day long. For all but the most brutal players, a 300 Watt amp flat-out is fine. They are nearly as efficient as the 130, IMHO a hair less musical and more clinical than the 130. Their cousins are now rated 600 Watts PA duty. Again if you want bass with serious bottom thud, you want the copper-coil tame-cone 15B.
For "tone", I like a smaller amp with a four-Ten or two-Twelve array. Four "lesser" Tens close together approach the efficiency (yes, and price) of a single super-speaker but with more aural complexity. The 2X12 is a great cab also.
Topic: Purchase of D130 or D130 F (Read 10772 times)