Alpine Type R to the rescue

[talnlnky]

Originally Posted by sqcomp

The sound of the woofer has a lot to do with the enclosure...

Taln, you want to comment on this subject?
.

Sure, like with anything in phsyics... audio is a game of compromises. the speakers, the box, they are all a combination of compromises.

Sealed boxes are pretty much a "if you mess this thing up, you have no business in audio" type box. it's hard to mess up a sealed box... but it can be done.

Ported boxes take a bit of knowledge to properly design and build. Ported can sound just as tight as any sealed box can if properly designed. The problem with that is that 99% of premade ported boxes are designed to have a high tuning.... around 40-45hz. High tunings cause a giant spike in the group delay of the subs which means muddy sound. In order to resolve that problem, you'd have to tune the box lower, which means the box will end up being bigger, and also be quieter in the 40-60hz range (where all the rap beats are).

The way a sub is built also can have a great effect on if the sound will be tight or muddy. Often times the high powered subs sound muddy because in fact they suck... By this i mean they have giant voice coils with a very high inductence (Le) rating which means they can't respond quickly to the changes of the electronic signal... it has nothing to do with the size of the cone (which is a huge myth). There are a few high wattage subs that do have low Le ratings, but they are few and far between. the old JBL GTI subs had some of the lowest Le ratings i've ever seen on a sub.

if you start out with a sub with a crappy Le, even a sealed box may sound muddy... if you start out with a quality sub... even a poorly designed high tuned ported box might sound decent.

For reference... the best sounding sub I ever owned was a 12", was rated 1600rms, and had an Le around 1mH. Companies often don't like to advertise the Le ratings... but try comparing that 1mH to others out there.... some subs are over 4mH, I've seen midbass drivers as low as .13mH.

[Alien Mantis]

Good info there.

Did you notice the Inductance rating depends on the frequency tested?

Higher freq = lower Le

So you need to compare the Le at the freq the sub will play at, or the number is meaningless.

[talnlnky]

Originally Posted by Alien Mantis

Good info there.

Did you notice the Inductance rating depends on the frequency tested?

Higher freq = lower Le

So you need to compare the Le at the freq the sub will play at, or the number is meaningless.

you're kinda missing the point... I could also say that the load/inductance that the amp will see at a specific point is determined (at least partially) by what type of box, and tuning the sub is located in.

when they test subs, the generally followed practice is to do so with no enclosure (free air or open baffle) in a large room. For the values that require a signal to be playing in order to be measured... they will play a 1khz tone.

If sub A has a 4mH Le, it will always have a higher inductance than sub B which has a 2mH Le.... regardless of frequency, as long as all other variables are the same.

[Alien Mantis]

Well yeah, that actually was my point!

If they use some standard for the tests, then you could compare them.

I understand what you mean about lower inductance is better.

But everything can be overcome with MORE POWER!


( But mine goes to eleven! )