What is the speaker design paradigm here?

[kchilaka]

Folks,
I recently acquired a set of Infinity Floorstanding cabinets without drivers. These are two way floor standers from the Infinity Reference 2000.5 speakers. I was hoping to use the cabinets in a future DIY project by fitting some very nice mid-bass drivers and some ribbon tweeters. I was trying to do my research on what kind of mid-bass drivers might fit in these cabinet. I wanted to model these cabinets in SpeakerWorkshop with a few driver choices to see what response I might get when I realised that these cabinets were not simple ported cabinets. Oh no. The front bottom grills on these hide a perforated front baffle. I thought the fronts of these speakers (below the drivers) was solid wood but it turns out that the entire front face of these cabinets have a fine pattern of holes. I have no idea how to model these speakers now. Does anyone know what this type of design is called? Its like the speakers have two ports. One is the gigantic bottom firing port tube and the other vent is the collection of front holes. The schematic diagram calls them an "Acoustic Filter". Another thing to note is that the entire cabinet is fully stuffed with "fluff" and I do mean fully and tightly stuffed. Is this whats called an aperiodic design? I am enclosing a picture of the speakers..
Any pointers will be helpful.

An externally hosted image should be here but it was not working when we last tested it.

 

[doug20]

Sounds similar to the new Pioneer speakers getting HUGE reviews because they sound damn good and they are $199/pair, they have some tube "sucking out standing waves"

Home Theater: Pioneer's Speaker Genius Hits Low Price Point

Pioneer's Speaker Genius Hits Low Price Point
Posted Thu Sep 23, 2010, 5:58 PM ET
By Mark Fleischmann



Andrew Jones of TAD has been designing hugely underrated speakers for Pioneer for years. Until now his bleeding-edge designs have been high-priced. But the SP-BS41-LR hits a new low price point of $199/pair in hopes of moving units through big-box retailers. The curved cabinet is cooked and formed, in lieu of the more conventional cut and fold process. Center and surround models are available to form a 5.1 system that will go for under $1000. The slim tower at far right is the Series 9, whose drivers were designed specifically for the enclosure. A vertical tube feeding out the bottom sucks away standing waves.

This from Kal on Stereophile
Stereophile: The 2010 CEDIA Show: Day 1

The biggest surprise for me, however, was the really robust-sounding small 2-way from Pioneer Electronics, the **-41, with a 5" polypropylene woofer and a 1" soft-dome tweeter linked by a 6-element network. Andrew Jones was proud to demo this (the shipping cartons label these as "Audio Artistry by Andrew") as a representative of a new line that includes a smaller bookshelf design, a floorstander and a subwoofer. It sounded remarkably clean and spacious as a stereo pair and outlandishly better than its surprising price would suggest. All the others in the line are available at Best Buy but the BS41 can be bought only from Pioneer's website. Oh, did I tell you the price is $199 and that's for a pair? WhooHah.

 

[kchilaka]

Well,
These speakers are about then years old. While they are not from the glory days of Infinity, they are from the reference series of Infinity in 2000 so they probably do have considerable design work in them... They are rated to go down to 35hz at -3db with a small 6.5 inch woofer..

Sounds similar to the new Pioneer speakers getting HUGE reviews because they sound damn good and they are $199/pair, they have some tube "sucking out standing waves"

Home Theater: Pioneer's Speaker Genius Hits Low Price Point




This from Kal on Stereophile
Stereophile: The 2010 CEDIA Show: Day 1

 

[jason_watkins]

These are an aperiodic bass reflect speaker to abuse the common terms. Akabak should be able to model it if you can figure out a number to represent the lossy-ness of the perforated baffle. It might be best to do measurements then just tweak the constants in Akabak for the closest match.

 

[jackinnj]

These guys (Pioneer SP-BS41-LR) were mentioned in the September 2011 "Stereophile" -- $149 -- with Amazon Prime they showed up the next day. They are very, very nice for the price.