Identifying Legitimately High Fidelity Loudspeakers: Myths & Facts about Cabinets

[admin]

The cabinet is a big expense in the total budget of a loudspeaker system. Cost cutting is an easy area for some manufacturers to rationalize by using pseudo science and also knowing most consumers won't take a peek inside the box to see what's going on. This article explores some of the common myths we've uncovered and discusses how poorly executed decisions can ultimately compromise the quality of the product. The sum of the parts really does matter in loudspeakers, as does the engineering behind making all of the parts work together as one unit. Take the time to research the mechanics of the enclosure if the manufacturer is willing to espouse the information, and pay close attention to our reviews where we often dissect the speakers to give an inside look and analysis. If you are seeking out truly high quality loudspeakers, don't settle for mediocre or even average build quality, especially if the price tag doesn't justify it.

Discuss "Identifying Legitimately High Fidelity Loudspeakers: Myths & Facts about Cabinets" here. Read the article.

 

[Paul_Apollonio]

Interesting article.

Thanks.

 

[GranteedEV]

there was no mention about the value and benefits of constrained layer (viscoelastic) damping...

 

[SnowmaNick]

Question on myth#4

Paul et al,

Thanks for an informative, easily understood article. If you have a moment, I have a question in regards to the bottom line of myth #4 regarding fiberglass and poly fill inside an enclosure.

Bottom Line: Some poly fill / dacron can be a compromise and better insulation (ie. fiberglass or high density poly fill) will improve the sound quality of your speakers. If the manufacturer is willing to spend the time and money to do it right, that is a bonus. If not you as the end user should be willing to replace the stuffing of your speakers. It is neither difficult nor expensive, and can result in an audible and measurable improvement in your sound.

Does this recommendation change for various types of ported/vented enclosures? In particular, enclosures that use passive radiators? Since the passive radiator relies on the pressure from the cabinet, does adding (any/some/more) insulation to such a design affect the tuning or performance in a negative way?

Thanks in advance.

 

[shadyJ]

An excellent article! I'm looking forward to more articles in this series, it has been highly informative so far. Thanks!!

 

[ratso]

BTW i went to RMAF last year and for the most part was mostly disappointed by most speakers i heard. but those bambergs sounded pretty damn nice IMO.

 

[Paul_Apollonio]

Stuff it

Paul et al,

Thanks for an informative, easily understood article. If you have a moment, I have a question in regards to the bottom line of myth #4 regarding fiberglass and poly fill inside an enclosure.

Bottom Line: Some poly fill / dacron can be a compromise and better insulation (ie. fiberglass or high density poly fill) will improve the sound quality of your speakers. If the manufacturer is willing to spend the time and money to do it right, that is a bonus. If not you as the end user should be willing to replace the stuffing of your speakers. It is neither difficult nor expensive, and can result in an audible and measurable improvement in your sound.

Does this recommendation change for various types of ported/vented enclosures? In particular, enclosures that use passive radiators? Since the passive radiator relies on the pressure from the cabinet, does adding (any/some/more) insulation to such a design affect the tuning or performance in a negative way?

Thanks in advance.

Absolutely. The amount of stuffing in a vented enclosure must be chosen judiciously so as to not interfere with the passage of air through the port. Usually, they are less filled than a similar sealed box. (At least when I was younger, today anything goes). For a PR box, the issue really goes away since it is pressure only moving the PR. You need not worry about the filling jamming the port. It will affect the effective volume of the box, and therefore it should change both the tuning and the Q. This may be a small difference relative to the improvement you get in the midrange with a full range driver where the rear wave hits the rear panel, reflects, then tries (successfully) to exit through the cone again, out of phase with the initial wave. As for pollyfill, it is not all created equal. Hollofill does the best job of creating a viscous drag on the air. It is almost NEVER used, since it was more expensive than the junk most manufacturers install. Fiberglass should FILL the air, more than simply displace it. WHERE in the box the filing is stuffed also effects things. Behind the driver directly is going to decrease the Qms the most. I would say play with the thing and remember ALL OF THIS IS SMALL RELATIVE TO THE IMPORTANCE OF SPEAKER POSITIONING on your bass. Have a nice day.

 

[Paul_Apollonio]

there was no mention about the value and benefits of constrained layer (viscoelastic)

there was no mention about the value and benefits of constrained layer (viscoelastic) damping...

I think you should ask the website for your money back then.

 

[lsiberian]

I would like to point out for the home builder or modder that 4" 6 to 8lb density rockwool is the most effective product I've used to absorb the internal energy of a speaker or sub. It's much easier on the skin that fiber and cheaper than high density fiber.

 

[lsiberian]

there was no mention about the value and benefits of constrained layer (viscoelastic) damping...

It's completely unpractical in a commercial setting. The labor required is insanely high. I'd not ever put one in a speaker I wanted to sell. Unless the customer was willing to wait a lot longer and pay a lot more.

 

[Paul_Apollonio]

Best of all Long Haired wool (Sheep hair)

I would like to point out for the home builder or modder that 4" 6 to 8lb density rockwool is the most effective product I've used to absorb the internal energy of a speaker or sub. It's much easier on the skin that fiber and cheaper than high density fiber.

http://total-insulation.com.au/pdf/Rockwool-Accoustical-Properties.pdf

Long haired wool has the reputation as being the best material of all, but is price prohibitive. Best bang for the buck is still fiberglass in my opinion. I've tested JUTE, which looks like Rockwool, but do not see it for sale many places. If you have a source in the USA, go ahead and share it here. Thanks.

 

[DD66000]

All my boxes are sealed, braced, and I stuffed them to the max with FG.
Stuffed boxes certainly make a difference.

 

[farrow099]

So I'm at my local Best Buy checking out some Klipsch speakers. It's a beautiful fictional day. The sun is shining, there are attractive ladies everywhere. Whatever...

Anyway, I say to the salesmen... Do you know if these cabinets are internally braced? And he replies, all of our speakers are built with the highest of standards! Next I ask what materials are used in the crossover network. He shrugs his head and continues thinking about whatever teenagers think about. Then I ask him to show me, but for some reason he refuses to pull out a woofer so I can peer inside! Apparently stores don't let you pull loudspeakers apart to check out their internal design.

Maybe it's just me, but the advice in this article seems a bit impractical. In many cases pulling out a woofer or tweeter would void your warranty! Aside from the knock test there really isn't much you can do without becoming the new owner...

 

[gene]

So I'm at my local Best Buy checking out some Klipsch speakers. It's a beautiful fictional day. The sun is shining, there are attractive ladies everywhere. Whatever...

Anyway, I say to the salesmen... Do you know if these cabinets are internally braced? And he replies, all of our speakers are built with the highest of standards! Next I ask what materials are used in the crossover network. He shrugs his head and continues thinking about whatever teenagers think about. Then I ask him to show me, but for some reason he refuses to pull out a woofer so I can peer inside! Apparently stores don't let you pull loudspeakers apart to check out their internal design.

Maybe it's just me, but the advice in this article seems a bit impractical. In many cases pulling out a woofer or tweeter would void your warranty! Aside from the knock test there really isn't much you can do without becoming the new owner...

That is why you rely on competently written professional reviews as a starting point. Some manufacturers will also post interior shots of the cabinets and parts used or at least mention them in their specs page. The more data a manufacturer is willing to disclose the better a consumer can be informed.

 

[farrow099]

Fair enough, but I for one would like to see more head to head comparisons! It's expensive for an average guy like myself to compare speakers side by side.

 

[gene]

Fair enough, but I for one would like to see more head to head comparisons! It's expensive for an average guy like myself to compare speakers side by side.

we do annual shootouts but most manufacturers don't like them. Ironically some of the manufacturers that spout the DBT mantra like 3rd party shootouts the least!

 

[gtpsuper24]

Hopefully this doesn't start an arguement, but I recently purchased a set of Arx A1s and A2 center, replacing my Axioms. I've always been a fan of Axiom, but now comparing the cabinets to the Arx the Axioms are not a solid and seem to echo with the knock test compared to the Arx. I compared the A1 bookshelf to the Axiom M2 and M22 and its not even fair the A1 weighs almost as much as the M22 and out weighs the M2 by 4-5lbs, to me thats a lot considering its a 5.25" bookshelf.

Reading this article the EP600 subwoofer kept coming to mind, its a 47" tall cabinet with no or next to zero bracing, but yet they want close to $2k for it. I posted on their forum and couldn't get an answer why Axioms subs are so much more compared to the other brands. For example the EP600 vs the SVS PB12+, the SVS out performed the Axiom in every test sound wise. The SVS has a better built cabinet, more powerful amp, and a slightly beefier driver thats also handmade just like Axioms, but yet Axiom charges $500-600 dollars more than the SVS. So my question to them was what factor causes Axiom to charge such a premium compared to the other brands?

 

[scott911]

Holy Editorial Notes! good stuff though both of you.

A nice smaller shop I used to go to - which was also a repair shop so maybe they were a bit handier - would pop off the tops of amp to show the various bits, and had various bit (tweeters, woofers, etc.) on the shelves near most of there inventory. I suspect a not-best-buy place would be pretty accommodating of honest questions.

thielaudio.com actually has a series of five or six videos on there site were they show the building of cabinets in their factory. It's kind of "raw" but you definitely see everything that happens on the floor in Lexington (from pallets of sheet stock to the final finishing and beyond) to create those beauties.

 

[gene]

Holy Editorial Notes! good stuff though both of you.

A nice smaller shop I used to go to - which was also a repair shop so maybe they were a bit handier - would pop off the tops of amp to show the various bits, and had various bit (tweeters, woofers, etc.) on the shelves near most of there inventory. I suspect a not-best-buy place would be pretty accommodating of honest questions.

thielaudio.com actually has a series of five or six videos on there site were they show the building of cabinets in their factory. It's kind of "raw" but you definitely see everything that happens on the floor in Lexington (from pallets of sheet stock to the final finishing and beyond) to create those beauties.

that's good stuff. Years ago when I worked my way through engineering school, I worked at a local hifi shop. I used to bench test amps for customers prior to installing them at their place. I also would routinely show them internals of loudspeakers by popping out woofers of the floor models. They loved it and it gave them an appreciation for good engineering. This seems to be lost today in a sea of psuedo science and dumbing down the public that good parts aren't needed for good sound....

 

[AcuDefTechGuy]

So my question to them was what factor causes Axiom to charge such a premium compared to the other brands?

Axiom likes to rip people off.