Double Chamber Reflex Vent Question

[Guss]

Double Reflex Alignment
Sorry to bother you guys but I can't find the info I'm after... In order to save some space I'd like not to eat up the internal volume of one of my two chambers with the ''linking'' port so heres the question ; can I link the two chambers with the port entierly placed in the 2/3(bigger one) part of my enclosure.

Goodnight
Goss

[sreten]

Simple answer - of course you can.

sreten.

[Benny the 2.]

Sorry, but I've always meant, that both chambers in such an alignment should probably be of same volume?

A german brand uses such an alignment with their fullrange- speakers, and we had a lot of duscussions about how to figure out the secrets of such an alignment...

[GM]

.....that both chambers in such an alignment should probably be of same volume?
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News to me, at least WRT Weems concept. Here's an informative site: http://planeta.terra.com.br/educacao...negro/english/

GM

[hunter audio]

hi

well i can go into lengths as to why you can have a whole lot of combinations for dual chamber bass reflex - the classic is to tune one chamber at around 70 hz while the other at 35 hz bothe the chambers wikk have different internal volumes - instead of going further

please go over Audio Amateur - Loudspeker Designs Speacial - Issue there are whole lot of dual chamber reflex s and the priciple is explaind there

i am a transducer design engineer - and know the relation ship why t/s parameters are there beleave me there are whole loy of approaches - other thatn the conventional - all you have to do is keep the mechanical load on the drive unit - suitable to the drive unit ypu are building it for

how you do it ts parameters is a guidance

suranjan

transducer design engineer

[kelticwizard]

The conventional way of building one, as invented by Augspurger and modified by Weems to fit Thiele-Small parameters, is shown in the following link.

Pay attention to posts 35,36, 37 and 38.

http://www.diyaudio.com/forums/showt...3570#post93570

[GM]

>well i can go into lengths as to why you can have a whole lot of combinations for dual chamber bass reflex - the classic is to tune one chamber at around 70 hz while the other at 35 hz bothe the chambers wikk have different internal volumes
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Agreed, there can be many combinations, though most aren't worth the effort IMO. Frankly, I don't much care for the 'one note' sound of the popular 2:1 ratio design.
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>......as invented by Augspurger......
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Actually, Karlson's early '50s K-15 is the earliest use of a DBR chamber I've seen so far.

GM

[kelticwizard]

Originally posted by GM
>......as invented by Augspurger......
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Actually, Karlson's early '50s K-15 is the earliest use of a DBR chamber I've seen so far.

GM

When I said Augspurger invented the box, I meant the box with those specific chamber ratios and tunings.

Weems credits Augpurger with the development of the box with the ratio of chamber volumes and tuning method he uses. Weems just related the whole thing to Thiele-Small numbers, which came later. This seems to be the most popular setup that Claudio and others use.

Perhaps Karlson's enclosure has a different tuning, or maybe unspecified chamber ratios and tunings?

[GM]

Karlson's original design used a 1.0:0.707 chamber ratio with identical CSA vents. I haven't reverse engineered his later ones yet, but it seems reasonable to me that Augspurger just adapted Karlson's invention (if indeed it's truly his idea) to offset the lack of mass loading by a long tapered vent. I don't consider adapting an existing design to suit your needs as an invention, but I don't know how the patent office views it.

GM

[kelticwizard]

Augspurger got his patent. Weems gave the patent number in an article he published in an electronics magazine, which I lost. Happily, I did remember to keep the Xeroxes of the section of The Loudspeaker Design Cookbook which gives the same information on how to build them. Unfortunately, the Loudspeaker Design Cookbook does not contain the patent number to Augspurger's version of the unit.

Nevertheless, it useful to know that Karlsen invented the box first, with Augspurger patenting an improvement in it. Up to know, I thought Augspurger came up with the whole concept.