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Discussion Starter #1 (Edited)
Hi All,

So, upon browsing the News area of the forum and seeing the Bose VideoWave TV reminded me of their Wave Radio. I remember a few years back going to a Bose store in the mall and they had the demo of their new (at the time) Wave Radio. It was a see through, clear design that let you see the inner grooves. Interestingly it had a lever next to the unit. When pulled, it moved the speaker (woofer?/driver?/whatever the correct term is:huh:) forward away from the unit. Speaker away, sounded very thin, like something was missing. Speaker within the Wave Radio, sounded awesome. Best way to describe it is that it sounded "warmer" so it must have had some bass to it.

To my untrained ears, it sounded good. Now, I just got into the whole home theater thing this past year (thanks to the members here for making recommendations). And I still consider myself a listening novice. That said, in retrospect, the question is why did sound good to a "regular Joe"? What would the trade off be for a 2" or 3" driver put into that sort of housing? Deeper, but muddier sound?

It's just stuff I had not thought about or considered. Any input would be enlightening.:rubeyes:

H.
 

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It didn't sound good when out of the enclosure because it was driven free-air (no enclosure) when it was back inside it was "loaded" and the waves from the front and rear of the driver were seperated creating a better sound. Not very scientific but i hope i gave you somewhat of an idea.:T
 

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Waveguides (as Bose call them) are basically transmission line ports that are designed to boost bass performance. They will have that effect on any speaker when design properly. Bose just use the kind of show you saw to make people think that its their system doing something special. Any speaker will sound worse in the same situation, if removed from its port. These Bose systems use the waveguide as the bass speakers, with separate speakers for the highs, and they are effectively removing the bes speakers (which is why it then sounds tinny) and its only like you taking any speaker and removing the bass driver. The effect is it sounds bad, and when replaced it sounds better than bad and makes you go 'ooOOoo'. Its not necessarily that they sound good, its that they sound better than what they compare them too on the sales floor ;).

The problem with Bose is not really their quality, its the asking price for the quality on offer when compared to the rest of the market. A wave guide radio/cd player sounds half decent for such a small device, but its incredibly over priced. Also, the environment you hear them sold in is hardly a critical listeners environment, and Bose seldom allow their kit to be displayed next to other kit in dedicated audio stores, because the stuff around them will sound at least as good, but have a smaller number on the price tag. This kind of thing is really about advertising and trying to impress you on the spot so you make the purchase, nothing more. As you really learn about what else is available for that kind of money, you wise up. BTW, I am a one time Bose Lifestyle system owner, and just such an in store demo got me too.
 

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I once had the opportunity to take a Bose Wave Radio apart (for a friend - it had failed to operate some short time after the warranty had expired), and I can say the internal construction, particularly the CD player deck, appeared to me to be very "cheap". I've never had the chance to actually hear one (this one had a dead microprocessor and didn't resuscitate well), but I know the asking price isn't justified by the construction when compared to a lot of other audio products out there. Of course, Bose does a lot of advertising and must recoup with a larger profit margin which is part of the reason for this. Personally, I would stick with more name brand component equipment if I were investing in something to be appreciated for its sound, although the Bose WR does have its place in some applications.
 

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Here are a couple of fun tests, they require a poor audio source such as the speaker on a cell phone;

Start the speaker (cellphone, cheap computer speaker, etc.) playing some music that has a broad spectrum of sound such as pretty much any pop music. Take the speaker while it is playing and put it on the floor in the corner of a room, preferably with hard flooring. Notice a difference? BTW, I have actually used this technique to allow multiple people to listen to music from my cellphone. Got some wierd looks.

Now take it and put it in various containers, like pots, pans, trash cans, notice the differences? Try holding it at various levels from the bottom of the container.

The wave radio with some level of research used similar phenomena, to tune the back wave of the speaker and feed back to the listener so that it boosts the relatively lower freq's that the speaker doesn't put out very well due to its size.

I believe that you will find it to be a minature "Transmission Line" in nature.

Paul
 

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Hi All,

I remember a few years back going to a Bose store in the mall and they had the demo of their new (at the time) Wave Radio...
To my untrained ears, it sounded good. What would the trade off be for a 2" or 3" driver put into that sort of housing? Deeper, but muddier sound?
I think there are some factors at play. First, it was a few years ago you heard the demo. Now that you're into home theater, you might have a different assessment. In addition to carefully controlling/isolating their displays, Bose has been caught "tweaking" the test environments and signals fed to their products to make them sound better in a demo environment. Wave Radios do sound better than the average $20 clock radio, but I think you may find their real world performance disappointing.

I'm amused with ther "proprietary waveguide speaker technology". Back in 1925/1926, when Victor released their first electrically recorded (Orthophonic) 78's, they also released a new series of Victrolas. They still used acoustic playback, but instead of using a simple exponential horn as in the past, the used a folded horn design, the same principle as "waveguide". They used extensive research to come up with the exact dimensions of the folded horn. The sound was much better, especially in the bass. Even now one of these Victrolas sound pretty impressive.

Back in the 1980's, I owned a pair of DCM Timeframes, which use the line transmission principle. They had relatively small drivers and sounded good.


For just a little more than the $500 they charge for their Wave Radio, you can buy a nice Harman Kardon receiver and either Ascend Acoustics HTM-200's or SVS SBS-02 speakers. With either set of speakers, that setup would play rings around the overpriced Bose clock radio.
 

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Bose equipment is overpriced junky stuff. I know, because I own some of it. I was disassembling my car dash, and came across the the center speaker of my Bose car stereo. It was a little paper-cone driver, and everybody knows paper is bad in a car because of the dampness.
 

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Discussion Starter #8
Okay, let me recap the info thus far. So from what bambino, Dan, Paul, & Doug have said, the housing of any speaker is what takes a driver and makes it sound good. Take the speaker out of the housing and it sounds terrible. The housing may have funnels/tunnels like the Victrola and Bose Wave which is some sort of transmission line port.

Pardon in my lack of knowledge of how a speaker works... is this transmission line port the same as how much air a speaker is moving? That's what creates the richness of sound, right? The larger the speaker means more air can move and the lower the frequency can go?

If the folded horn design has such great results on the low end, why doesn't everyone use it?
 

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Discussion Starter #9
I once had the opportunity to take a Bose Wave Radio apart (for a friend - it had failed to operate some short time after the warranty had expired), and I can say the internal construction, particularly the CD player deck, appeared to me to be very "cheap". I've never had the chance to actually hear one (this one had a dead microprocessor and didn't resuscitate well), but I know the asking price isn't justified by the construction when compared to a lot of other audio products out there. Of course, Bose does a lot of advertising and must recoup with a larger profit margin which is part of the reason for this. Personally, I would stick with more name brand component equipment if I were investing in something to be appreciated for its sound, although the Bose WR does have its place in some applications.
I looked at the Cambridge radio line, soundworks?, and some of the reviews so far stated that it sounds good when working, but that the reliability is iffy.

Out of curiosity, which applications for the Bose WR were you thinking about? :blink:
 

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Discussion Starter #10
Bose equipment is overpriced junky stuff. I know, because I own some of it. I was disassembling my car dash, and came across the the center speaker of my Bose car stereo. It was a little paper-cone driver, and everybody knows paper is bad in a car because of the dampness.
My understanding is that drivers can be made from several different substances. Paper ones can sound very good and can also be treated - presumably making them better. Can a paper driver that's been treated more resilient to dampness? (e.g. better for car use?)

And what type of material is a car speaker generally made of?
 

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My understanding is that drivers can be made from several different substances. Paper ones can sound very good and can also be treated - presumably making them better. Can a paper driver that's been treated more resilient to dampness? (e.g. better for car use?)

And what type of material is a car speaker generally made of?
Well many car speakers ARE made of paper because it's cheap, and you are supposed to trade it in 3 years. Treated paper may be better than untreated at resisting dampness, but I have no data on whether or not that ends up being true.

Better car speakers are made of polypropylene. I have two JLAudio subs that use polypropylene cones, and after 10 years of car use and unheated garage storage they sound awesome.

My truck woofers are paper, which disintegrated and I replaced- with more paper cone speakers because I don't expect the old truck to outlive the speakers.

My gripe with Bose is that they could do better with the money they get, but choose not to compete on the merits of their equipment, but spend enormous sums on marketing to the masses. Their demos are highly contrived. You can't put your own music on the Lifestyle(R) system, because then you would notice how bad it sounds. You can't A-B compare their equipment to competitors because it is set up by itself. The source material you do hear has been recorded especially to show off their equipment. These practices are deceptive.

To get back to the OP, the wave radio uses horn loading to improve the sound of a small speaker. the enclosure acoustically matches the small driver to the air outside. This isn't anything new, as has been explained.
 

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Okay, let me recap the info thus far. So from what bambino, Dan, Paul, & Doug have said, the housing of any speaker is what takes a driver and makes it sound good. Take the speaker out of the housing and it sounds terrible. The housing may have funnels/tunnels like the Victrola and Bose Wave which is some sort of transmission line port.

Pardon in my lack of knowledge of how a speaker works... is this transmission line port the same as how much air a speaker is moving? That's what creates the richness of sound, right? The larger the speaker means more air can move and the lower the frequency can go?

If the folded horn design has such great results on the low end, why doesn't everyone use it?
Folded horns are very efficient and have smooth frequency response down the the horn cutoff frequency. Below that they roll off. For a small table top system, I would not recommend a horn because horns need to be large to work well. Bose can get a lot of volume out of the small horn, but there isn't much bass present.
 

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Okay, let me recap the info thus far. So from what bambino, Dan, Paul, & Doug have said, the housing of any speaker is what takes a driver and makes it sound good. Take the speaker out of the housing and it sounds terrible. The housing may have funnels/tunnels like the Victrola and Bose Wave which is some sort of transmission line port.
Sort of. I'd change your sentence from "the housing" to "the appropriate housing". Think of an automobile and its engine. They have to be matched. You can't take an 80hp engine and put it in a car designed to be powered by a 300hp engine and vice-versa and expect to get optimum performance. Also, folded horns and transmission lines have some similarities, but they aren't the same type of design.

Pardon in my lack of knowledge of how a speaker works... is this transmission line port the same as how much air a speaker is moving? That's what creates the richness of sound, right? The larger the speaker means more air can move and the lower the frequency can go?
No, transmission line not about how much air is moved, but how that air is controlled. Going back to our unenclosed raw driver, one reason they don't sound good is that sound waves are eminating from both the front and back surface of the cone. Based on a lot of factors, including room size, your distance from the driver, etc, these waves cancel each other out or they boost each other. It's unpredictable and creates a sonic mess.

Good enclosure design aims to prevent this. Different methods are employed. Sealed designs aim to "trap" the waves off the back of the drivers and keep them from mixing with the waves from the front. Other designs, such as folded horn, transmission line, tuned port, etc. aim to capture some of that sound energy from the back of the speaker and exploit it. Each design has strengths and weaknesses. I think the proper execution of a particular design is more important than the design concept itself in obtaining good sound.

You are right, there's an old saying "there's no replacement for displacement". Also, it takes a lot more energy to produce a low frequency note at the same sound pressure level (SPL) as a high frequency note. A lot of air has to be moved. Moving this air takes a combination of surface area and cone excursion. Roughly speaking, I can move the same amount of air with a smaller driver that has a longer throw as I can with a larger driver with a more shallow maximum throw. That's why you can't assume that a particular 15" subwoofer will go deeper and louder than a 12" or even 10" subwoofer. As with any area of speaker design, there are tradeoffs.

If the folded horn design has such great results on the low end, why doesn't everyone use it?
I'll cite the legendary Klipschorn as an example. It was truly revelutionary when it was introduced in 1946 and is still in production. It does have a great low end. The problem is, the lower you want to go, the bigger your folded horn needs to be. K-horns go deep, but they're huge! Also, K-horns use room walls and floor to effectively extend the size of the horn. That means they have to be placed in corners. If you're lucky enough to have a dedicated music room, that might not be a problem, but for the average family, it might not work so well.

Since their introduction, though, other speaker designs were able to accomplish deep bass in a much smaller package. The Acoustic Research AR-1 launched in the mid 1950's provided as much or nearly as much bass in a bookshelf sized speaker.

My old DCM transmission line speakers did sound good, but they were big floorstanders. They also didn't have deep bass, but I was using a subwoofer in conjunction with them. I eventually replaced them with smaller speakers that actually sounded better.
 

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I think it's kind of amusing that when I got to the bottom of this thread I found a Bose advertisement (by Google). I wonder if they get many click-throughs on Bose bashing pages.

I have sat through a Bose demo in their Home Theater room and wasn't really impressed. Years ago when my ears were untrained and home theater was a new phenomenon I may have been. Oddly enough the store was pretty busy, so they are doing something right.

Mind you their market is baby boomers who have lots of money and are too trusting. Wait a few more years as the baby boomers start retiring, their incomes are reduced and generation Xers take the throne. Companies like Bose will have to take a different approach if they want to grow in the decades to come.

Of course Generation X is still rife with uneducated buyers and to quote P.T. Barnum, "A sucker is born every minute". Generation Xer's are more likely to research on the internet however so it's our job, being the informed ones, to educate them.
 

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Okay, let me recap the info thus far. So from what bambino, Dan, Paul, & Doug have said, the housing of any speaker is what takes a driver and makes it sound good. Take the speaker out of the housing and it sounds terrible. The housing may have funnels/tunnels like the Victrola and Bose Wave which is some sort of transmission line port.

Pardon in my lack of knowledge of how a speaker works... is this transmission line port the same as how much air a speaker is moving? That's what creates the richness of sound, right? The larger the speaker means more air can move and the lower the frequency can go?

If the folded horn design has such great results on the low end, why doesn't everyone use it?
Porting is simply a way of extracting more low end performance from a driver. Bose simply use it to get the most from very ordinary drivers to give ok results.

Your line of thinking on moving more air relating to more bass is on the right track though. Folded horns are simply another method of this, but their lower rank on the popularity lists is due to them being pretty difficult to design properly, and they are usually very large as well, which puts restrictions on their use.
 

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Discussion Starter #16
Hmm... I've read the responses and understand the vaule:price for Bose. But there seems to be much to learn & understand regarding the inner workings.

So, is there a good writeup or video about speakers? (e.g. Speakers 101?) This might fill up some knowledge gaps from reading things ad hoc.

Thanks,
H.
 

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There is a mass of info on the subject, but it will take a long time to learn enough to really be a guru if starting from scratch. What is it you are trying to figure out?
 

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Discussion Starter #18
There is a mass of info on the subject, but it will take a long time to learn enough to really be a guru if starting from scratch. What is it you are trying to figure out?
Hi Dan,

I was just trying to understand the physics on how speakers work (what part does what and it's effects) and hoping through the "Intro to speakers" understand the lingo used around here.

For instance, I didn't realize until Doug's post, "Other designs, such as folded horn, transmission line, tuned port, etc.", that folded horn, transmission line, & tuned ports are considered designs versus fundamental elements (coils, cones, and other stuff).

Just trying to be educated. The more I know about a topic, the more well rounded I am. Now I know what it feels like on the other side when I'm talking about computers and people's eyes glaze over. If I can only do that with speakers, I can have another star on my belt. Personally, I like to think of it like merit badges. :T

H.
 

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Well the porting/horns/transmission lines etc are all aspects of cabinet design. All speakers need to be placed into a cabinet to produce sound, otherwise the front and rear waves from the speaker cancel each other out and no sound is produced. There are some exceptions to that rule, but to keep it simple thats basically the rule.

Different kind of cabinets have different effects on the sound the speaker produces, and most notably is the effect a ported system has on the bass reproduction of speaker. Standard ports, horns and transmission lines are all different types of porting that gives different results, but thats basically ow things works.

Subs are the simplest speaker, operating within a very small range, all of which is bass, and generally using a single driver with a single purpose. Speakers are a bit more complex as they typically use 2 or 3 types of speakers to cover their entire working range. Ports can still be used in their cabinets for better bass production etc, but generally a lot of manufacturers split the cabinet up for the different drivers that are in there. The driver all need to be carefully matched to ensure they work together well, and you need to add in crossovers to limit the working range of each driver in your final speakers design.

Speaker building can be a very complex task, and its not uncommon for people or manufacturers to mix different types of cabinets within the same speaker to get desired results, making the thing even mode complex, but ultimately much better.

Bose really dont do anything fancy in real terms. There small speakers are just left to work their entire range (which is actually quite limited by many driver standards) and use a mid bass driver in a dual chamber vented enclosure to get the most bass possible from the rather ordinary driver they use. The end results are far from bad, but they also arent the which craft they would have you believe. At the end of the day, its the asking price of their system that is the real killer. Their systems are sold on style more than anything, and discerning listeners will pick this out. It was actually my unhappiness in my expensive Bose system that first got me online to see what was wrong. Ive never looked back :T
 

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From what I understand, this Bose is a folded W-bin to increase bass wavelength. This increases the effective diameter of the speaker/driver. Of course, the lower the frequency, more power demand for equal sound level. The radiation from the back of the speaker is 'ideally' phase transposed into the same phase as the front sound projected from the driver, through reflection, so as not to cancel the two soundwaves.

It's probably a good introduction to the potential of sound reproduction. Maybe Bose can consider individual speakers along this line. I saw the B&O Chrystal speakers with remarkable specs in a small package. :spend:
 
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