Talk:Woofer

sennheiser is not an austrian but a german company. probably was mixed up with akg. —Preceding unsigned comment added by 77.220.104.3 (talk) 13:36, 2 January 2008 (UTC)

Pjay: added some text to try and make this clearer. Used some text from my own site, i.e., I gave myself permission to use my work. I still don't like the flow. There is a lot more woofer info on the loudspeaker page, but I think the woofer page should be deeper. Someone please show me how to post a picture on this site. P

To upload a pic, go to 'upload file' and follow the instructions.--Light current 21:39, 15 May 2006 (UTC)

Thanks, got it!. Added more text from my site on woofers and hertz. Pjay

BTW did you know that you can sign and date your posts automatically by just typing 4 tildes ( ~~~~), or clicking on the signature tab at the top of the edit window?--Light current 22:00, 16 May 2006 (UTC)

Merge with loudspeaker

I don't think this should go to loudspeaker. That entry is already very large and focuses, correctly, on the completed unit. This is a separate item in my mind. Pjay 22:10, 20 May 2006 (UTC)

I agree. The loudspeaker article is already long enough. Rsduhamel 07:05, 20 June 2006 (UTC)

i second that. its a seperate component of the whole.—Preceding unsigned comment added by [[User:{{{1}}}|{{{1}}}]] ([[User talk:{{{1}}}|talk]] • [[Special:Contributions/{{{1}}}|contribs]])

Frequency ranges aren't quite right, misc

I don't think the freq-range figures are quite right. Many small hi-fi woofers run up to 2 or 3 khz, not "a few hundred" Hz. Some large PA or high-effiency home woofers run up suprisingly high. The article should be changed to reflect that some woofers (in 2-ways mostly but also many 3-ways) cover most of the midrange.

That diagram isn't entirely related to woofers and might confuse some people.

The freq-response section defines "frequency" but nothing about FR.

I could touch some things up but not now. --Howdybob 13:32, 8 June 2006 (UTC)

I have the master sheet for the chart. I think it covers the subject well for what it is and think it works well for a visual on size versus range. If someone has a better idea, write me and I will be happy to make changes. I do not want to make it complex with full range drivers or TLs or other anomolies, keep it simple. thanks. Pjay 15:22, 6 July 2006 (UTC)

I changed the range in the first paragraph to "thousand". While "hundred" may have been the correct usage many years ago, common usage today includes woofers which can easily be used into the thousands. It is not about when the terms were generated, woofer-squawker-tweeter, it is about how it is being used today. A scan of any of the main driver producer sites show "woofers" which can go into the thousands. The most common woofer in use today is the 7" which is almost always used from 45-2500 Hz. Pjay 17:31, 11 July 2006 (UTC)

Pjay, this image is very misleading and incomplete. It doesn't talk about beaminess at the higher end of each frequency range, doesn't talk about the HUGE importance of cabinet design relative to woofer size and doesn't mention 15", 18" or 21" woofers. Also, energy from the human voice doesn't cease above 5k; harmonics up there are very strong. I'd like to see this image taken out of the Woofer page. Binksternet 19:46, 27 August 2007 (UTC)

Not the same thing

Ok, all woofers are loudspeakers, but not all loudspeakers are woofers. That's enough for NOT merging. Not to mention tweeters, sub-woofers, mid-ranges and so on... —Preceding unsigned comment added by ??? (talk • contribs)

So what? That could easily be taken care of by creating sections in the article to deal with specific types of speakers, woofers, tweeters, etc. Not a good argument for not merging. ==ILike2BeAnonymous 18:22, 18 July 2006 (UTC)

I agree with unsigned here. Not only do the various types of driver differ in size, and in technology (imagine a ribbon woofer!), and so deserve separate articles, but joining htem together woudl invovle the reader (perhaps new to the field) in an attempt to separate out issues pertaining to one or the other. For instance, Thiele-Small is simply irrelevant to tweeter construction, mounting, or use. But central to the modern use of woofers.

We already have an article on loudspeakers, which is getting pretty large. We shouldn't be trying to shoe horn in other articles as well.

On another point, ILike2Be deleted some informatin I'd added to the diagram for woofer, claiming it was TMI. This is an encyclopdia, and it's not clear to me this is a reasonable objection. In any case, the information was added to a schematic diagram where it would be most relevant and least abstract. There is, after all, some discussion of the consequences of excursion lmiits on the use and conseqences of variations therein. That's why I reverted. ww 00:41, 16 February 2007 (UTC)

That material should go in the article proper, not jammed into a caption, especially since the diagram is labeled as being "not to scale" anyway. +ILike2BeAnonymous 00:49, 16 February 2007 (UTC)

I see the point about scale, but the diagram does show an overhung vc. As for the point being in the text, well... I invite you to add it. You can probably use the parallel passage in loudspeaker (was it?) as a model. Till then, the point is not made in this article, is useful to the understanding of some of the tradeoffs, and so encyclopedic (an objection you are no longer making?). You and I have gone round and round on this one, and I'd invite others to comment before yet another.

And I forgot first pass on this reply. This is not a diagram of a standard loudspeaker, but of a particular implementation of a common type. Hence my change of 'standard' to 'dynamic coil'. Do you see that it is standard, by some standard? Or was the revert reflexive? ww 17:04, 16 February 2007 (UTC)

Regarding the "overhung" stuff, no thanks: that's your baby. I'm no expert on that aspect of speakerology, so you'll have to add it yourself.

By the way, further regarding this topic, I would think that this really should go in the main article about speakers, since it deals with speaker construction. Which is yet another argument for merging this article into that one. What do you think?

Regarding the term "dynamic coil", the thing is, nobody uses that term for speakers. While it's true that there are other types of speakers besides what is technically called a "dynamic" (meaning, confusingly, magnetic) speaker, such as electrostatic, the vast majority of speakers in use are the magnetic type. Therefore, it would be easiest and most correct to simply call it a "standard speaker". (You're free to point out this distinction, in the text, if you so desire.) +ILike2BeAnonymous 18:48, 16 February 2007 (UTC)

Long throw voice coil

If a (sub)woofer is current driven, and housed in a sealed cab, would it be a waste to use a driver with a long throw voice coil ? I need a n expert answer on this please-- not just a guess. THanks--Light current 19:11, 23 September 2006 (UTC)

IF your sealed box is really sealed, it will be tuned for some particualr characteristics in the driver. Really big box (more or less an infinite baffle, or more reaonsable size, more or less acoustic suspension). Most sealed box designs are tuned for low frequency performance, and in a sealed box that implies acoustic suspension and considerable cone excursion. IF that's so, and your box is so tuned (deliberately or accidentally), you will have to have either a vastly expensive magnetic structure, or an overhung voice coil. Nobody makes the first, so you'll have to settle for the second.

On the other hand, if you go for some other tuning in your sealed box, you might be able to avoid the inefficiency of an overhung voice coil. If you go for a really large box, you'll have to have a pretty stiff suspension to provide restoring force, and you might be able to avoid overhung. But if you want reasonable low frequency performance and high efficiency, you've got more than under/over hang problems. Use a low frequncy horn, or a bass reflex to get the efficiency you're after. And big enough ones (horns) or properly tuned ones (vented) to get the bass performance.

More important perhaps, you should decide what you want from this speaker system. Perhaps a sealed box would be just the ticket, or perhaps not, but until you're clear about what you want, you're not in a position to decide such things as hang. Once you're clear on that, design a few systems (with imaginary drivers -- or steal some T/S params from a variety of real drivers from some catalogs) with one of the Thiele-Small computer programs to see how things will fit with other issues, like the WAF, and how much the enclosures can cost in trouble of materials. figure on doing several of these befroe you get a feel for what the various issues are. Only thne will you be in a position to decide on any actual driver. Or maybe you're devoted to low powered tube amps, in which case I don't think you want to think about the inefficiencies of an acoustic suspension type sealed box. ww 00:53, 16 February 2007 (UTC)

Link for people looking for WFR

should there be a link at the top to Wilderness First Responder, which is sometimes referred to as "woofer"? Quezlath 22:31, 30 April 2007 (UTC)

Four-inch driver too small says who?

I put a citation needed tag on the phrase that says a multiple of four-inch drivers can't get low in frequency. It's my experience that the enclosure is a major factor in low frequency extension and that the most important thing is to have enough total area in your drivers. Multiple four inch drivers in quantity could be made to have a lot of area. Binksternet (talk) 01:32, 8 April 2008 (UTC)

Lots of drivers handling the same signal introduce issues of mutual interference, even if they together have sufficient area to move air at low frequencies. I think what wa smeant here was something about the trend in 2-way speakers to use a 4-6" mid-woofer as the lf driver. I think we can reword to increase clarity. ww (talk) 07:37, 4 June 2008 (UTC)

Mutual interference issues can be overcome by novel enclosure design. A low-distortion subwoofer cabinet could be designed that used a mass of 4" drivers; it's just not normally done. I don't think the phrase is worthy of inclusion here. Binksternet (talk) 17:28, 4 June 2008 (UTC)

Cooling magnetic structure approach

I reverted your reversion as most of it was language, not content, and the main content issue is in reference to the cooling business. Wayne Parham of Pi Loudspeakers in Tulsa has patented (IIRC) such a widget and is selling it. His test data suggest considerable reduction of power compression issues. I'll be digging up the patent nr (if I can find it...) in the next day or so, so we can cite that. Or we can point to some of his reported data in the Pi Forum discussions. ww (talk) 07:37, 4 June 2008 (UTC)

My language changes made the article more readable, why revert that? For instance, "wattage" is a colloquial term; its use was not optimal. Also, the phrase "Energy not transferred to the air is converted to heat" is imprecise; energy applied to the voice coil is converted to heat directly in the coil, air is the second medium encountered. Furthermore, you deleted the explanation of "power compression", a significant result of coil heating that precedes coil damage. I will be bringing all of that back into the article.

Regarding the Parham cooling technique: no patent or white paper was cited, nor was there any mention of prior work in the field of woofer cooling. The small scale of the paragraph seemed overly promotional to me. If a section of cooling is introduced here, where's the history and prior art? Where's Danley's 1988 air-cooled loudspeaker patent? Where's the 1994 Nordschow et al work on flow-through cooling? Where's the 1999 Cahill et al work on passive cooling? Brock Jabara's 2006 patent on cooling structure? If Parham's patent is brought in, it needs to be accompanied by a fully-fleshed out section so as to place it in context. The patent itself will be sufficient; I see no need to cite an online discussion forum that isn't vetted by the scholarly community.

There's already a very limited discussion of cooling techniques at Voice coil. Perhaps the expanded cooling section can go there. Cooling of loudspeaker drivers applies to more than woofers. Binksternet (talk) 17:10, 4 June 2008 (UTC)

I didn't see wattage and agree it had to go... Mine was a rollback of a prior rollback, so a restoration of a status quo prior. Nothing else should have been changed, including anything on power compression. Not sure what happened.

We both seem to have been trying for more readability and polishing off the awkwardness which seems to accrue, sort of like mold.

As for the Parham thing, there was mention of a patent (I'm not sure I'd bet large money on it, but... -- still on my to do list). The entire issue of cooling deserves some coverage somewhere, but a mention should be made somewhere prominent (not buried in a subsidiary article) that it's a significant issue (changing VC impedance w/ temperature) currently rarely addressed even when clearly necessary. I had no promotion in mind, but was attempting to note that there was an issue.

As for cooling not being limited to woofers, certainly it's true that it comes up elsewhere, especially in PA applications. But outside of that, the major issue for on woofers is DC bias and turn on/off thump. Woofers do, after all, handle by far more power than any other driver type, so it's a bigger issue with them.

Perhaps the thing to do is have a large section (Parham + all the rest...) somewhere, mention the issue here (with a reference to more complete coverage)? You sound like you're more on top of it than I, so... ww (talk) 21:57, 4 June 2008 (UTC)

Filter theory in horn and transmission line enclosures

I'm taking out the parenthetic statement that horn and transmission line enclosure designers don't work with filter theory. I personally know horn-enclosure designers whose products have passive or active filtering included. Binksternet (talk) 21:53, 24 September 2008 (UTC)

I thouhgt the passage referred to T/S filter theory application, not crossovers. Maybe it can be reworded to make this more clear? Comments? ww (talk) 00:10, 25 September 2008 (UTC)

What would be a better way to say this? Try it out here first. Binksternet (talk) 05:21, 25 September 2008 (UTC)

Surrounds

This article doesn't really talk about "woofer surrounds" so i thought i'd throw in a bit. woofer surrounds are the small, usually foam rings that connect the cone to the cabinet. they're necessary for a woofer to work properly, because they limit the vibrations, keeping the cone from moving to much. nowadays they are usually made out of some sort of industrial foam, and they tend to rot if kept in storage, or in sub-optimal conditions. you;ll be able to tell if they're rotting because whenever you get a bass beat your speakers will waffle terribly. its totally fixable though, just buy a repair kit. —Preceding unsigned comment added by 64.6.88.225 (talk) 14:13, 4 October 2008 (UTC)

Standard sizes

Please add some info on how the standard sizes like 8" 10" 12" 15" are measured. Seems to be approximately the outer frame diameter? http://www.jlaudio.com/header/Support/Tutorials/Which+Speaker+Size+is+Right+for+your+Boat%3F/Which+Speaker+Size+is+Right+for+your+Boat%3F/483328 http://www.jlaudio.com/c2-650-car-audio-c2-speaker-systems-99617# — Preceding unsigned comment added by 71.167.68.30 (talk) 18:48, 2 December 2013 (UTC)