i dont get it i really dont know what makes a subwoffer more a sq sub then a spl sub other then a spl sub can take a big pounding casue there meant for it. But i really dont get what sound quality u get out of a sub.I heard a JLw7 and it just sounded like big strong bass to me but then i also heard a L5 in a ported box then i wasent as loud but it still sounded about the same.
SPL subs are designed to be louder, and not necessarily natural.
Kinda like the difference between cartoons and real actors.
BassDuder
Unregistered guest
Posted on
SPL usually have a huge excursion and move alot of air but are ony really powerful at low frequencies like 25-40. a SQ sub will have a frequency range of 30-500 or so and tends to hit more notes giving you a "richer" sounding bass rather than just a huge THUMP! every second or so.
hope this helps. also SQ subs tend to have a lower sensitivity than SPL subs. SQ is always the way to go unless you just intend to impress people and not really listen to the music.
"but are ony really powerful at low frequencies like 25-40. a SQ sub will have a frequency range of 30-500" thats an interesting statement since most subwoofers are the loudest at around 50-60hz and generally speaking a SQ sub is usually praised for going into the lower frequencys such as the avalanch going down into the 10s
there are a number of components that make for a good "sq" sub. the primary, imo is how accurate the sub plays with regard to how the music was originally recorded. this accuracy should not be for just a given frequency. but rather throughout the entire range of frequncies for which the sub is responsible (good frequency response). in addition, the driver should remain accurate regardless of volume/excursion (linear response). the primary factor of this accuracy, or transient response (the flip side of frequency response), is inductance. this is the time the vc holds the current before it starts to respond to the amplifier's applied voltage. so the sub should reproduce the low frequencies of a song as close to identical to the original recoding as possible. no extra boominess or clangy tinging that some listeners have no problem with (particularly the boominess). so, will a bigger, heavier sub be any slower than a lighter, smaller 10"? nope. not necessarily. its all a matter of inductance. the lower the inductance, the quicker the response of the sub. you also have to take into consideration the mechanical noise that the driver makes when moving. anything besides heard from the driver besides the actual music also subtracts from the sq.
I think what Bassduder was trying to differentiate was the the applications that each is used for.
Yes, 60 Hz is probably one of those most efficient subwoofer frequencies, probably due to the fact that this is the range where most electrical bass guitars, keyboards, bass drums, and other sources are used to playing when accompanying music.You will find that if you listen to music the bass guitar will be playing the octave between 40-80 Hz on the most regular basis. Thats why it 60 Hz seems to be so much louder than the other frequencies.
Not too many "real" instruments go below 40 Hz. The tympany drums go to like 30 Hz. The pipe organ goes down to 20 Hz or so. The electronic keyboard goes down somewhere down there, but since it is not a real instrument, I disqualify it (lol).
Please keep in mind that these are their lowest extensions, not their normal range. So even the tympany drums, electronic keyboard, and the pipe organ still play between 40-80 Hz on average pieces.
Getting back to what Bassduder was saying about 25-40 for SQ subwoofers; it is because thats where the Sq subs are most efficient because they are tuned between those frequencies. When you tune a port to say 32 Hz, there will be a 3dB gain at probably 38-42 Hz and then the cutoff starts to drop. By the time the frequency response drops to below 3dB below par it will be 32 Hz.
For SPL subs it remains relatively the same except for the fact that they may be tuned at lower frequencies. Tuning at lower frequencies means larger wavelengths. Larger wavelengths means more air. More air means more force. More force means more VOLUME. MORE VOLUME MEANS MORE "SPL".
The typical SPL subwoofer is designed with a very tight suspension, strong motor, long excursion capability, and a stiff, light cone. Many are designed to have a rather high Qts because this results in a peaky output near port tuning. The suspension is typically tight enough to raise the Fs up to the 30s or 40s. Typically an SPL setup will tune the system in the 60-70hz region, not necessarily because of the subwoofer efficiency, but because the cabin gain of the vehicle is highest in that region, dependant on the car of course. So, the subs are designed to have their efficiency in that region as well. Plus, as frequency gets higher, less excursion is required to produce the same SPL. Excursion is the inverse square of the frequency, and for every octave down, it requires 4 times the excursion and 16 times the power. So 20hz will require 4x the excursion that 40hz would require for the same output, and 20mm of excursion at 40hz will be a lot louder than 20mm at 20hz. An SPL system wouldn't be all that loud in the 20hz range since it would be limited by the capabilities of the subwoofer driver.
A SQ subwoofer is designed to produce a flat frequency response and minimal phase response in the intended enclosure. The Fs will be as low as possible, it will have a linear motor design, and the cone and suspension elements will be designed to produce optimal response in the intended enclosure. A SQ subwoofer designed for ported or small sealed enclosures will have a low Qts, usually in the .30-.40 region. These subwoofers have a strong motor, a light cone, and a relatively loose suspension. In other words, they are efficient. A subwoofer designed for a sealed box or IB application will be more resonant and less efficient, with either a weaker motor, heavier cone, or tighter suspension, or any combination of those. They will have a Qts that typically ranges around .5 for sealed boxes and closer to .7 for infinite baffle.