An Update

Just a quick update on the previous entry.

We have enlisted the services of a very accomplished company to attend to our carpentry needs. Very reasonably priced too. So much so we won’t be handing out any of their business cards…

That said, there seems to be a growing number of individuals hell-bent on obtaining the rare and the special without parting with any significant money. Most are quite happy to purchase a very able and beautifully styled set of loudspeakers at 50% under cost. (Which is about 25% of the price of vastly inferior popular brands of speakers, one might add. Let’s rather not start naming them – they’re well known, after all.) If we can find a way to supply these prospective clients without having the sheriff kick down the door, we’d really be in business!

Ironies aside, it seems we might have to set up an own little carpentry shop and route certain of our manufacturing processes via the “in house” drawer.

On which we will, in due course, report.

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September 2011

Perhaps it’s time to simply report. PHI has finally managed to thread a few tiny roots into the Capetonian soil. Some orders have been placed and we’re starting an exciting and somewhat industrial styled range of Voigt pipes, tailored around a number of very promising drivers.

After an advertisement was placed for cabinet makers (our man is still in Johannesburg, and will probably remain there…) we were inundated with responses. These were interviewed and a short list was compiled. Unfortunately they seem to suffer equally from an endemic disease here; one we ourselves have been trying hard not to contract: terminal slowness. I suppose it takes some very special powers of will to be able to focus on work in such a beautiful and relaxed environment. Perhaps some small measure of this would seep into our products, rather than into our staff. (Basically: we’re still on the look-out for dependable, skilled and intelligent wood craftsmen – who care for a bit more than simply earning a salary).

That said, we have started distributing a range of imported amplifiers – mostly single-ended EL34 valve amplifiers. Of course custom designed amplifiers would be what just about anyone would prefer to have. Unfortunately not every music lover can afford these days to pay the price such a luxury entails. Rather than have budding audiophiles buy some generic assembly line opprobia, we thought we might as well tone down our high-mindedness a bit and give these individuals a chance to own an amplifier they could learn to love, even after they have upgraded to something they have dreamed of for long. Look at this page for more details:

Also in the starting blocks: we have realised it makes sense to offer some of our loudspeaker models as kits. Voigt pipes are rather bulky and shipping costs to remote counties (like the USA) can be prohibitive. At present it’s still only an idea and therefore not yet linked to our home page, but keep watching this link for updates:

Perhaps I should leave it at this for today, with perhaps a promise to report back soon.

Keep those disks spinning.

Posted in Audio, High-End Audio | 2 Comments

And this PHI thing?

I’m a newcomer to the blogosphere, and perhaps choose to remain such, well… until I’m not one any more. That being said, there is a bit of reporting, as it were, I’d like to do. On PHI, that is.

PHI (perhaps I shouldn’t blithely assume everyone knows: PHI Bespoke High-End, as it’s currently known, a company I started, who occasionally build some very nice loudspeakers) started out, as I mentioned, as quite a few things seem to do, as an itch. (A rather nasty sentence this, but I’m keeping it.) I read somewhere (I think it was on TNT Audio) about Sonic Impact’s T-Amp. Now the T-Amp, for those who haven’t yet formed an opinion, is a little grey plastic amplifier. It’s shaped and sized somewhat like a truncated bread roll with some cheap clips at the back and a nasty knob that goes click up front. It has space, unbelievably, for a bunch of AA cells (batteries) in its shell, which nevertheless manages to be mostly empty. Did I mention it’s made of plastic? The thing is, this little amp plays really well, and if one replaces the knob with something better and boxes it up neatly, with some proper terminals, some might say you’ve found yourself a sub-R300 high-end amplifier. I did this, but water came through the roof and killed it. Darkness between the notes seems to be its shtick, and good low bass (! – and not only for its size). It is only a 10W amplifier, but people get away with less than one Watt, once they get their speakers sorted out. (Sorry, I’m not talking to you head-bangers, though you might be surprised if I started…)

Either way, I was running a set of (please don’t sue me, I’m writing from memory and I just got up) 83dB/Watt Wharfedale bookshelf speakers at the time, which is the crux of the biscuit, as Zappa might say. (OK head-bangers, a 100W amplifier playing into these little speakers – and don’t get me wrong, they’re rather nice in their way – would play as loudly as a 6.31W amplifier into PHI’s latest loudspeaker. There’s more to it, of course, and quite a bit of that “more” is in favour of the 6.31 Watt set-up.) So, in short, the T-Amp wasn’t powerful enough to drive them to realistic volume levels. (Yup, there’s that too. If Rammstein concerts are your thing, you might struggle to produce these in your mom’s lounge, for more than one reason. But anyway.)

So I had to build some cheap speakers for the amp I’d bought to drive my speakers. I didn’t even try too hard and got it all wrong; but they sounded great anyway and Voilà! – PHI.

So that’s how you do it kids. I’ve since lost all my money, my house and most of my friends, but I’m famous now and it’s great fun. And I’ll be building a few more for sure. Probably shortly. And if I become, as I hope, a blogoholic, you might just read about them here.

Posted in Audio, High-End Audio, Music | 1 Comment

A rose, by any other name.

The Rise and Fall of the Lesser Load-Dependent Adaptive Power Bicore-Controlled Electromagnetic String Driver.

La Monte Young would certainly have come up with a different name, but he might just as much have sat back and lit up for this one. Such is minimalism.

It started as a robot. Actually not. It started as a starry-eyed vision of a minimal 8-node circuit that remembers so well that it would repeat phrases spoken at it. 8 timed circuits strung in a loop, high-impedance loudspeakers acting as both inputs and outputs, with trimmers to ground and DIP switches as output mixers. I actually built it; on a neat PCB I designed before testing. It was bound to work. Of course I switched it on with bated breath, timidly whispering “hallo” into one of the speakers. It did exactly nothing – no pop, no phlogiston escaping, no hum, no hiss, no furtive words darkly spoken: “daddy, is that you?” Not once. At least it’s predictable I thought, thinking of politicians in Africa. It has turned out remarkably more predictable than that.

That’s where the robot first came in: I showed it to my friend Willem.

“Ah, a BEAM circuit.”

“BEAM?” He typed the word into Google.

“It’s an octo-core.”

“Well, it isn’t working,” I said defensively.

“Mark Tilden…”

You get the idea.

Then Willem’s dad wanted to make an art work with BEAM robots crawling over some letters. We were called in and a quantity of money was put on the table. Willem immediately went to buy smokes and I started struggling with a few components on a lit from below glass table. By the time I started needing an own pair of glasses, the thirty or so components had become five. And it was still working. The euphoria evaporated as soon as we tried it on a solar cell: it needed more voltage, and a little more current. Miller engines simply didn’t. Around the time I reduced a second 555 (and Willem his 400th cigarette) to holy smoke, his dad returned and I was fired. “Mark Tilden,” they said. I moved to Cape Town.

Time to get serious – I called up Brendon Bussy. Brendon builds small stringed instruments from fish cans and dowel sticks and plays on them. He also plays the mandolin rather well, sometimes through Audiomulch and sometimes not. One day he wants to teach informal settlement urchins to do the same things.

By now I had Wednesdays in the bag. Brendon would pick me up at the Waterfront and we’d tinker ’till it was time to go home. The circuit had decided to remain being a bicore – we dropped one component (why five if you can have four?) strung a loudspeaker in circuit and powered up. It buzzed like hell. We swapped components – it still buzzed, exactly like the hell it was buzzing like before. Interesting, we thought (although by now we’d started using words like “interezzting”.) There was one (not totally unexpected) phenomenon: whenever one pushed on the loudspeaker cone, the sound changed markedly. One could shift the pitch by about an octave without damaging the cone. This made sense – the loudspeaker impedance forms the resistive element of the RC timing circuit. Pushing on the cone changes the Thiele-Small parameters of the loudspeaker and moves around the resonance peak of its impedance curve. The circuit reacted to this, by oscillating faster or slower, depending on which “side” of the impedance peak it was operating. This is not what every monostable circuit does. In addition the generated wave forms were quite complex. It had become moot whether this was because of “learning behaviour” (loop hysteresis) or because of complex interactions with the load due to impedance changes and reverse EMF. But the buzzing was monotonous and pitched right in a nasty region of one’s hearing, exactly there where Fletcher-Munson indicates the greatest sensitivity. A suitable resonator improved matters slightly, but it remained daunting to listen for more than a few seconds.

By this time it had become clear that we either needed oodles more variation, a different register or a different and more chaotic resonator than a loudspeaker cone. A fortnight before, Brendon had stretched a string across a lagoon at Kogelbaai to create a wind harp. This worked beautifully, producing a whole wreath of haunting drone-like sounds. If the practically linear movement of air over a simple string could produce such harmonics, the circuit-without-name would probably do at least as well. The next week we glued a tube onto a small loudspeaker driver and tried connecting it to a nylon string Brendon had strung across his work bench. Predictably it buzzed like hell. Sounds coming from a piezoelectric transducer stuck to a small fish can resonator (Glenryck, I think) were more interesting, but there still was a lot of “bleed” of the unmitigated loudspeaker buzz, even on the piezo output. We started winding solenoids, to create a drive which produces very little sound of it’s own. These didn’t work, no surprises, with too thick a wire gauge and too few windings. Brendon mentioned a door bell..

The next week I was greeted by a weird one-stringed instrument on Brendon’s bench, with the bridge and resonator (KOO Pilchards in Chilli Sauce) equidistant from the two ends. The string was steel.. We quickly removed from its cradle, re-wired and re-mounted the solenoid on a piece of wood, flanked it with a mild steel magnetic cradle with two cut-outs where the string could pass through and tried it on the naked string. It started buzzing, softly, but happily. A great relief. Brendon recorded a few minutes. Levels weren’t optimal. Perhaps another resonator. His old mandolin had a suitable steel bass string and didn’t object to being recorded. Exactly this, on a CD he hastily made me as I was leaving, is what I’ve been listening to for the last five days. We’re not even close to the end yet, I’m sure, but I think it’s time to start choosing a name for the circuit. And it won’t be Tilden.

Posted in Art, Audio, Music, Musical Instruments, Sound Art | 6 Comments

Hello world!

This message was sent out to a number of wine farms and finally ended up on 2oceansvibe:

As good a Hello World as any:


I’m 47 years old, a business owner/designer for the company PHI, have recently moved to the Cape and find myself in need of a source of supplemental income. I probably have way too many interests to make a good employee for any company, but suspect that I would be able to make up for this with sheer enthusiasm and a, probably essential, modicum of desperation.

I’m interested in just about anything that allows the possibility of attaining outstanding and uncompromising quality and which involves the mind and senses in some or other conjunction. These interests have, over the years, included the growing of orchids, writing, knowing just about everything about fine wines, working as a chef (and as a barman), collecting, studying, performing and composing avant-garde, classical and other music, steering motorcycles over terrain best avoided, lunging at much swifter persons in Taekwondo outfits and designing, and occasionally building, exceptional loudspeakers and amplifiers.

My life has, almost regrettably, also included roughly seventeen years of mindlessly offering coffee and tea to airliner passengers, leaving me out of touch with many of my earlier interests including physics, philosophy, psychology, languages and literature, the arts and astronomy. This I have begun to address.

What I would presently like to involve myself in is winemaking, or, perhaps more sensibly, the activities surrounding the making of wines – anything from working as cellar assistant to writing about or marketing wines. I’m not particularly skilled at deception and would as a consequence be much more comfortable if these wines were to be of undeniable quality, particularly if my activities were to include convincing individuals of buying them.

I’ll be sending this letter to any and all producers of wine I can visualise myself working for, hoping to be offered a chance of doing so and some degree of remuneration. For this indiscretion I hope to be forgiven.



Jacques van Zyl


Posted in Uncategorized, Wine | 1 Comment