I think i am starting to get this.

Esreuter

Hey forum.

Now this is just for discussion and my own self discovery, but i wanted to share with you all in hopes to learn more about the subject.

Until today i was still mystified by what people meant by boomy bass. I could'nt separate in my head, bass and boom. I thought that all low frequencies were boom, or a rumble.

I have been fervently searching for info on this and just end up more confused and a touch lost. today though i finally found one sentence that puts it all into perspective.

On, i think, avs forums one person posted how they had boomy bass, and that same person ran an experiment, using Lord of the rings, first one, the part when the balroc walks toward gandalf on the small bridge, the whole "you shall not pass thing." There is to be 2 distinct footsteps that the demon makes toward the wizard. Tuun step, tuun step, his experiment shows that boomy bass will not allow for the other footsteps and sounds to be heard clearly. Just one big mish mash of noise, step tuuuuuuutuustepuunuuuunnn, that was supposed to be each step mashed together. Now the opposite would be with clean and sharp bass, each step would be independent.

So i finally think i am starting to understand what is meant by boomy bass, i wanted to share that with you all. Please chime in to add your knowledge and experience. Something i would like to know is muddy the same as boomy?

i would next like to learn about speed, you guys here always talk about the response time or the "quick" of bass and other sounds.

By quick, are you meaning the ability of the speaker to vibrate and then stop, so that the sound is, well, to use the LOTR example above, one footstep, no sound, second footstep? Or is there something else meant by the speed of a speaker?

I am pretty sure its not tied to the speed of sound, since that is generally a constant.

Anywho, lets discuss it. I am particularly interested in the frequency response between the CSI a 6 and the LSi C, I am wondering how a 5.25in driver can have a lower frequency response than a 6.5in, i was always in the know that the larger the driver the lower frequency it can create. What do you guys think?

Thanks to all of you for your input and helping me learn all this jazz.

ESR:biggrin::biggrin::biggrin:

VR3

Rumble is the best description I know of - its like when something happens there is a harmonic following behind it - like Boom (rumble), foot step (rumble) - so when you get like double bass you get kick(rum)ki(ble)ck(ru)k(mb)ic(le)k(ru)

See what I mean?

Joe08867

What you posted is a pretty good description of boomy.

Muddy in my opinion is when the all of the frequencies are smeared. Think of an old boombox, that is the epitome of muddy sound. Everything kinda sounds the same, there is no real definition in sounds from bass drums to cymbals or a guitar and the singers voice.

Rumble is easier. Think of the scene in Jurassic Park when the T-Rex is first heard. That boom and then rumble. Like the glass of water in the car they look at. The initial boom and then the following ripple on the water. The ripples are the rumble.

tonyb

Esreuter wrote: »

I am wondering how a 5.25in driver can have a lower frequency response than a 6.5in, i was always in the know that the larger the driver the lower frequency it can create. What do you guys think?

Thanks to all of you for your input and helping me learn all this jazz.

ESR:biggrin::biggrin::biggrin:

It's not just the driver that determines how much low end it can push. Cabinet design, driver material used, crossover, applification, your room also plays into it as well as placement. In some cases, a bigger driver can pressurize a bigger room easier....or overload it. When you look at specs, you have to take it with a grain of salt becouse everyones environment is different and results will vary.
Getting to know your own room and how sound reflexs is most important to guide you as to what gear to buy and how well it will work within your listening area.

steveinaz

Boomy or 1-note bass is more a product of cabint resonance than anything, and is not musical. I didn't realize how much resonance my Energy C-9's had until I bought my Carbon 7 monitors. The 7's bass is FAR more musical.

newrival

This whole issue is why I love open baffle speakers. OB's have some of the most impressive and realistic bass I've ever heard. No cabinet resonance by definition. An issue, though, is that you need twice as many drivers to produce the same spl (As an overly general rule of thumb). But the 4 15's in my Emmy's are breathtaking. And flat to within .5db from 28kHz to below 20Hz helps as well

Anyways, about ten years ago I thought one-note bass was all you could get, but you could pay more to hear it louder. It's funny to think back to then. As so many point out on the forum, ignorance was bliss, and then we found Polk Forum.

Esreuter

Now newrival,

what do you mean by open baffle, is it the same thing as a port?

:biggrin:

newrival

Addendum:

Edit:
Sorry that was a bit of a tangent. I also wanted to say that it seems like you're on the right track with understading bass clarity. There are surely some bass heads here than speak to the issue on good authority - certainly better than I - but I think of it like a synthesis process: you have a perfect waveform (for the sake of conversation) and on the leading edge is your attack, on the trailing edge is decay. The closer your atack is to null in time the better. This translates to instantaneous sound. I.e., Pitch black to the smack or thud of a felted mallet on th skin a kick drum, followed by the thick rush of air and sound and then just as quickly, silent. No ramp up in spl, and conversely, no drawn out decay. I know this is a little different than HT use but its analogous. Like you and many have pointed out, that nebulous rumble that carries through a scene is the diiference. Good bass will have texture. A quick anecdote: I sat down and watched Ice Age 2 - yes, alone - and brought the sound up to reference level. There is a super impressive ambient atmosphere laid out that consists of hissing wind and this low drone of ice shifting and cracking. Its seriously cool, even if you dont like these kinds of movies. But the efect is fantastic. Anyhow, the bass is subtle, but its shifting and grinding and scraping and has texture to it that would normally just sound like a really long flub and rumble.

Well I hope there was something useful in there. So now that you know theres a difference, there is no hope fr you. You will now be seeking it out and paying dearly for it. We seem like we want to be helpful, but truthfully, misery simply loves company

newrival

Esreuter wrote: »

Now newrival,

what do you mean by open baffle, is it the same thing as a port?

:biggrin:

Not at all

Open baffle simply means there is no box. Well, thats an over simplification. The baffle is the portion of the speaker cabinet that the drivers are mounted to. In an OB construction the front baffle is all the structure there is. There is no back, and many times, there are no sides.

Emerald Physics:


As you can see the driver compliment is mounted to the baffle but is OPEN on the back and sides. This is advantageous for several reasons, and if you're interested, you may want to check out this thread: http://www.diyaudio.com/forums/multi-way/133016-open-baffle-theory-behind-benefits.html

If you want to get deep into it, check out Sigfried Linkwitz and his site over at LinkwitzLab.com

newrival

a famous OB design: Carver Amazing Loudspeaker

front:


back:

note: the boxes on the back are justr grill cloth and completely open

Esreuter

very neat.

i shall give those threads a read about the physics and such.

thank you for that info.

esr

headrott

reported.

Esreuter

whats all this reported?


i have seen that message from that guy on some other threads.

was there a violation?

Joe08867

When spammers post in threads we report them. We also post that they are reported so the mods don't get 50 reports on the same spammer.

It happens around here in waves.

Esreuter

oooo.

i got ya. and the ads are now removed.

byfthalone

I actually love Spam...fried with mayo

Joe08867

Spam, Spam, Eggs and Spam...

fishbones

By quick, are you meaning the ability of the speaker to vibrate and then stop, so that the sound is, well, to use the LOTR example above, one footstep, no sound, second footstep? Or is there something else meant by the speed of a speaker?

Most of it has been covered pretty well, but here's a little more for your thoughts...

Speed is related in a few different ways. One way is how quick a speaker can produce a sound (the attack). Another is how quick it recovers from that sound (crisp ending vs slower lag) which is just important, to allow it to prepare for the next attack. (btw, all the electronics before the speaker are all important parts to make this happen)

Another way some view the speed or quickness of a speaker can be the pace or dynamics of a speaker. Some have a quick upbeat pace that is toe-tapping, others can be slower and have a falling-behind or a feeling of sounding slow and unexciting. As with many things in this hobby, many times I've found it hard to understand certain terms until I've actually heard it from a piece of equipment.

mhardy6647

There are advantages and disadvantages to open baffles; ye cannae change the laws of physics. A driver's back wave can - and will - interfere destructively with the front wave; the impact this has on LF cutoff (or, more accurately, rolloff) will vary with the width and height of the baffle (the shortest dimension will determine the F3 point).

http://www.iol.ie/~waltonaudio/ob.html



Indeed, some woofers may be damaged by unbaffled operation - lack of control of cone excursion (especially at resonance, Fs) can have disastrous consequences.

There are some tricks used to extend LF response on OBs - one of which is to use drivers with a high Qts parameter (i.e., a "weak" magnetic motor); these will give a perception of extended LF response that is at least (I think) partially psychoacoustic.

It is possible to build OB subwoofers and extended range loudspeaker systems - such as the aforementioned Carver Amazings... but it ain't cheap nor trivial from a design/engineering perspective.