The above picture are Coral speakers drivers - Flat 8A. Have you heard of this manufacturer - Coral Audio Corporation? It closed down ages ago (1980’s if not mistaken) despite producing good quality audio drivers. According to my good friend Adrian, the brand owner now is Mitsubishi Corp. I wish some rich kind souls out there would buy it back from them and start the manufacturing again. *hint hint*
I was lucky enough to grab hold of a pair from Yeo from diyparadise 4-5 years ago. He might still have them. Drop him and email to test your luck! The driver I got is the Coral Flat 8A. It is the middle end model though.
The flagship model is the Coral Beta series. Apart from that, it does have some other types like the coaxial CX (6CX-501, 8CX-501, 10CX-501) series and also the full range series (4A-60, 8F-60, 10F-60, 12A-55. 12A-66). I did see the Coral speakers, model Beta 8 driver appearing in hifi4sale site before but I didn’t plunge into it due to $$$ constraints.
Above are the Coral Flat series frequency response graphs. All of them look pretty flat to my eyes. There is no serious dip on the impedance curve too, signaling that it is easy on the amplifiers, especially for low power single ended tube amplifiers. The graph looks pretty similar to the ones from Fostex.
According to Coral speakers manual, the goodies of Coral Flat series speaker drivers are:
- Paper cones made of pulp mixed with chemical fibers, specially molded.
- Copper-clad aluminum wire for voice coil.
- Powerful ceramic magnet.
- Dome made hard but light weight alloy for the diaphragm.
- Flat mounting method on speaker baffle.
From what I see, the frame could be improved further by sticking some carpet felt, BlueTac, or even damping material to control the ringing and dampen the driver frame. It looks a bit flimsy compared to the cast frame version.
Check out the Coral speakers, Flat series specifications – 91 to 96 db/w/m looks pretty good to me! They can be housed in horn cabinets (spiral, Hedlund, back loaded and etc), and also the vented and closed box recommended by Coral Corporation. I’ve a few friends that are quite good in speaker cabinets building if you’re into it. Contact me to get their details.
Check out the Coral Flat 8A back loaded horn design above. It stands at 820 mm height and 355 mm wide. It should not be a very bulky and big speaker to own. Do take note that tweaking is always needed for horn enclosure. It is not a 1 time right thing.
Check out the Coral Flat 10A Back Loaded Horn too if you have that driver.
If one is less adventurous, one can try the bass reflex or air-tight (closed) cabinet for the Coral speakers. It should be easy to build. One can try going for the local hardwood too since the book shelf types are not that huge in size. It should not be costly to have an exotic hardwood cabinet made locally. The tone will be much nicer. I’ve made a bookshelf enclosure previously with Cengal wood for Fostex FE167E and it really sounded pretty good. Or even better, go for the spiral horn by Masaaki Takenaka, with real wood. I’ve provided his link below. Check it out: Go to Spiral Horn example
If you’ve built something by Coral Corporation, do let me know so that I can share it with the rest of the viewers. It is a shame on me that I have not got the chance to build one myself. I will do so one day, one day that is…
Return from Coral Speakers to DIY Speakers
Return from Coral Speakers to DIY Audio Guide