Hello,
I have a pair of Altec 420A bi-flex speakers that I would love to use in a project.
They are the black-framed, "16 inch" type - refer picture. I think they are the same as the relatively common 15" white/silver 820A / 820-8As. I know they are different to the 820B.
These things have a huge Vas (~470L) and, unfortunately, large enclosures are not an option for me.
I was hoping to for some ideas as to what to do with them.
I was thinking (/hoping) that some form of open baffle or smallish ported enclosure might be acceptable. Ideally two-way with the 820A on bass and mid duty.
Any guidance appreciated.
I have a pair of Altec 420A bi-flex speakers that I would love to use in a project.
They are the black-framed, "16 inch" type - refer picture. I think they are the same as the relatively common 15" white/silver 820A / 820-8As. I know they are different to the 820B.
These things have a huge Vas (~470L) and, unfortunately, large enclosures are not an option for me.
I was hoping to for some ideas as to what to do with them.
I was thinking (/hoping) that some form of open baffle or smallish ported enclosure might be acceptable. Ideally two-way with the 820A on bass and mid duty.
Any guidance appreciated.
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The picture you show is a 420A ...not the 820, which is a very different beast. The 420A "Bi-flex" was an experiment in a two-cone design ...it was used in the "Santana" model from 1971 to 1978. As you can see in the pix, the cabinet size is kinda small & I think that is the common, (cheap) phenolic ring tweeter they're using. The tweeters are currently being made as reproductions of these and many others who used this tweeter. If that size enclosure is doable, you can make your interpretation of the vintage Santana.
-------------------------------------------------------------------------------------------------------------------------------------Rick...
-------------------------------------------------------------------------------------------------------------------------------------Rick...
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To get the best out of them I would dsp the single driver without tweeter. If its possible to compensate missing highs electrically.
Maybe tweeters as indirect reflecting tweeters not interfering on axis with the driver.
I would put them into the original size box but ported and DSPed.
Maybe tweeters as indirect reflecting tweeters not interfering on axis with the driver.
I would put them into the original size box but ported and DSPed.
Thanks for the replies.
Cab: from what I can google those Santana cabs are ~650x520x430mm. Roughly 110L with some very crude calcs. Theyy'd be at the upper end of the size range for me but happy to leave it on the table and an option. I'll do some research on porting design.
DSP: prefer to stay away from intrducing this into my very basic system 🙂
Anyone got a view on an open baffle option?
Cab: from what I can google those Santana cabs are ~650x520x430mm. Roughly 110L with some very crude calcs. Theyy'd be at the upper end of the size range for me but happy to leave it on the table and an option. I'll do some research on porting design.
DSP: prefer to stay away from intrducing this into my very basic system 🙂
Anyone got a view on an open baffle option?
Look up Je Labs open baffle . It works OK with 420 . Also Lampizator OB on his Diy pages. 420a must have some sort of helper tweeter to be usable . It's a very good driver.
Santana enclosure is not very good. Altec did not make a single good sounding factory speaker system and Santama is not an exception. It always puzzles me how a maker of fine drivers can produce such s@#$%%ty speaker systems. But that's not the end of the story. More amusing are people who glorify them. Anyway , 420 is a great driver . It has a killer tone. The problem is how to utilize its strengths . It's a universal problem with all vintage drivers. How to capitalize on thier strengths and ameliorate weak spots..
Santana enclosure is not very good. Altec did not make a single good sounding factory speaker system and Santama is not an exception. It always puzzles me how a maker of fine drivers can produce such s@#$%%ty speaker systems. But that's not the end of the story. More amusing are people who glorify them. Anyway , 420 is a great driver . It has a killer tone. The problem is how to utilize its strengths . It's a universal problem with all vintage drivers. How to capitalize on thier strengths and ameliorate weak spots..
@limono - thanks. I'd previously stumbed upon the Lampizator OB project that utilizes the 420A. Much prefer the look of the simpler Je Lab project. I might give that one a go - particualary as the the 420A has been tested with it.
Any recomendaions on bang-for-buck tweeters/horns to match the high-sensitiviy 420A? Seems the phenolic tweeters in the Sanatana cabs are not liked with the Altecs. Recommended crossover point for these speakers seems to be 3kHz.
Thanks
Any recomendaions on bang-for-buck tweeters/horns to match the high-sensitiviy 420A? Seems the phenolic tweeters in the Sanatana cabs are not liked with the Altecs. Recommended crossover point for these speakers seems to be 3kHz.
Thanks
Yeah, and for a long time now been recommending Morel 378 for a better replacement.
FWIW, etc., the bi-flex dates from at least 1954 with basically this cab design minus vents at least through 1968 = ~3.3247 ft^3/94.15 L and per this recommend aperiodic if vented.