The emailer was Victor from Aural Design, a Singapore importer/retailer with whom I occasionally share notes.

"After two years of R&D and numerous prototype cabinets, my customer and friend has 'perfected' a back-loaded horn for what is known as the most exotic single driver manufacturer known today, Feastrex from Japan. The horn enclosure is handcrafted from a mixture of HDF and Ply and optimized for Feastrex's 5-inch driver range which includes the NF5 Naturflux, the NF5 Monster Alnico and the field coil versions.

"The curved horn prevents the build-up of standing waves while effectively and efficiently extending the low frequencies to 45Hz even with the basic NF5 Naturflux. The cabinet is handcrafted right here in Singapore. While I consider the Feastrex drivers to be the best of their kind, prices are high. Algahorn is planning also to launch smaller and more economical models featuring single drivers from Seas, Tangband, Fostex etc. We will be showing the Algahorn at the coming Singapore ISSE 2009 show from Nov. 6 - 8 with Italian Tektron electronics and Almarro single-ended amplification."

After posting the announcement in our news room, I informed Victor that if a review pair became available despite the very unappealing shipping proposition to Switzerland, I'd be all ears. Hearing a Feastrex in the flesh had been high on my list since reading about these exotic drivers. While the genre of single-driver speakers has very specific limitations, the best of the breed counter with virtues that are difficult if not impossible to replicate to quite that extent by other means. As no-holds-barred statement efforts, Feastrex made quite a splash within the small niche-within-a-niche of audiophiles who take such speakers serious and are curious to stay appraised of current developments. Ever since their release, hardcore widebander aficionados around the globe had experimented with various enclosures and loading schemes to get the best from these drivers. The US Feastrex importer Joseph Cohen of Lotus Group America has settled on an open baffle augmented by twin woofers and a digital crossover. The Algahorn meanwhile focuses on the single driver in widebander speaker designs.

Victor continued: "You will definitely get a pair. The freight is nothing compared to the 20+ pairs of cabinets that were made and dumped. You know that I'm not the type to be easily swayed by claims. Before I heard the Algahorns, I did not like the many single driver speakers I heard. The shout in the higher midrange, the lack of detailed highs and muddy bass are all I ever hear. Despite using single drivers, some horns are also incoherent as they tend to load the drivers too much to give huge bass whereby the highs and mids are like a step behind the bass. I'm not saying that the Algahorn solved all these problems but the compromises made—such as extending the bass to only 45Hz—kept the musical soul and body intact. The cabinet carpentry is not like what one can get from Hornslet in Denmark but it's up there with most mainstream speaker manufacturers. The first pair has been delivered to a music lover who uses the Kondo Ongaku. He gave up his top-line Tannoy Westminster Royal for the Algahorn with Feastrex Monster Alnico 5" drivers. Feastrex's Teramoto Haruhiko-San and Akiyama Kazuya-San are here in Singapore to grace our debut. They like the implementation very much." [Prototypes below.]

Mr. Terence Wong of the website who covered the show for us took the opportunity and interviewed the representatives from Feastrex.

Not by Chance Alone: Feastrex’s Teramoto and Akiyama Jr speak to MOD AV
A chance encounter led to the creation of a loudspeaker drive unit company. Dr. Akiyama, current president of Feastrex, was trawling through eBay looking for speaker parts. Resurrecting the likes of old JBL, Klipsch and Tannoy model is an almost cultural obsession with many Japanese audio enthusiasts. He chanced upon an auction selling a JBL crossover network. After winning the bid, he met up with the seller, an artisan by the name of Haruhiko Teramoto. The two immediately struck a common chord with their shared interest in loudspeakers. Or to be precise, the perfect loudspeaker drive unit.

Teramoto-San and Kazuya-San, son of Dr Akiyama, flew down from Tokyo to attend the Sound and Sight exhibition. MOD had the opportunity to meet up with them and ask what all the fuss over Feastrex is about. So what is a perfect driver according to Feastrex?

Teramoto-San: To understand the perfect driver is to ask what is sound. What does sound mean? Dr. Akiyama and I have spent a lot of time thinking about this and why it is that so many speakers do not make sound that renders music meaningful. Then we looked at the choice of materials which go into the making of drive units and it became clear that the perfect driver did not yet exist. We decided that if we wanted to perfect loudspeakers, we first had to make our own drivers.That's how Feastrex began.

We began with the membrane. Naturally, whatever material is used will influence the sound. We found that using hand-made Japanese washi paper using coarse fibrous bark of the mulberry tree made naturally without the use of chemicals produced the sound that would become unique to Feastrex. Avoiding chemicals during the manufacturing process means that the cone will be stable and long lasting. We only have a few washi makers in Japan remaining and we source from one maker who can give us the correct type of paper we need for the membrane. The famous painter Picasso also used washi from this same maker so you might say that washi is good for both sight and sound.

Then we hand-apply the lacquer that seals the cone against moisture. This has to be done by hand, applied and finished. I personally see to it that each stage of the process is strictly followed and there are many rejects for even the slightest flaw. I can produce as many as 100 pairs of drive units per month but because of the stringent quality control process, I can only deliver some 20 pairs, sometimes as few as 10.

MOD: You offer both permanent and field coil magnets. Why?

Teramoto: For permanent magnets, we only use Naturflux and Alnico magnets, never ferrite. Ferrite magnets are good only for PA speakers!

MOD: Neodymium magnets are popular.

Teramoto: Neodymium magnets have no ‘feeling’. We chose Alnico because of the ‘tone’. It has good magnetic flux and works well but let me explain about the ‘relative permeability’ of magnets. In free air, the mu is 1. Ferrite magnets give a mu of around 1.1. Alnico magnets have a mu in the region of between 5 and 7. Hence Alnico gives better control, better tone and better sound. But field coils can do even more. Using pure iron as the core material for a field-coil design, we obtain a mu of over 4000! That is a big jump from Alnico. The next stage is our Permador core which uses a mixture of 49% cobalt, 49% Ferrite and 2% vanadium. This gives a mu from 10,000 to 20,000. Why field coils? The difference is in the micro and macro dynamics. Field coil drivers can play 5 to 10dB louder before the core saturates and the magnet starts losing control.

Field-coil drivers use DC voltage to ‘energize’ the core, making it more powerful than any permanent magnet. The voltage supply to the core is very important. Recently we came up with a constant current power supply which not only provides a steady DC voltage, it also regulates the current supply. If the current should fluctuate, the sound destabilizes, something to do with the back EMF. However once the current is regulated with stabilization, the sound improves!

Editor's comments: The above exchange fails to explain why paper in general—and washi in particular—is a superior membrane material. Arguing that Picasso used it for painting is just as meaningless as stating that bullet-proof vests are made of Kevlar. No instrument is made of paper or Kevlar, hence this type of justification for the use of these particular materials for drive units is irrational. To discount ferrite motors as fit only for PA applications is one thing, explaining more precisely why would be quite another - and why ferrite is okay again for field-coils. All too often, audio explanations from artisan quarters serve myth building but don't properly explain why certain choices were made. If the promised opportunity to review a pair of Algahorns does indeed materialize, I shall endeavor to interview the Feastrex designers by e-mail myself and ask more pointed questions - Ed.