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SILICON
SILIC
CHIP
www.siliconchip.com.au
Publisher & Editor-in-Chief
Leo Simpson, B.Bus., FAICD
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Greg Swain, B.Sc. (Hons.)
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2 Silicon Chip
Publisher’s Letter
What next for hifi enthusiasts?
Late last year, I visited the Sydney Hifi Show with one
of our contributors, Allan Linton-Smith, who has written
the report in this issue. I must say I was staggered at the
stratospheric asking prices for some of the exotic gear on
show. “Yes Sir, we can let you have a pair of these fantabulous loudspeakers for a mere $100,000 and that is a special
price just for the Sydney show!”
Well naturally I had real problems controlling the urge
to splash out and buy. Ah, actually that’s a fib. I did not.
I wonder how much of this exotic gear was actually sold
at the show.
Another interesting aspect was the number of valve amplifiers on display. Now
you might have heard of “cricket tragics”, those people who keenly follow the
Australian cricket team no matter how dire their performance. Well, it seems that
there were a significant number of “valve tragics” at the Hifi Show as well, going
into raptures over the “sound” of these masterpieces. These poor deluded souls
really do believe that valves are wonderful; much better than those despised solidstate amplifiers with their vanishingly low distortion. What piffle.
Even if it was true that valve amplifiers are superior, you would be hard-pressed
to make any objective judgment about the sound quality of the loudspeakers and
the driving amplifiers in typical small hotel rooms – which is where most of the
exhibits were. Unfortunately, that is the drawback of most hifi shows; inevitably,
exhibitors demonstrate their gear in hotel rooms.
Having said that, there were some exhibits which did sound pretty impressive and
that was particularly the case where the program material was carefully selected,
the volume was not at deafening levels and the room had only a few people, seated
in an optimum listening position.
Also at the show were a number of high-end high definition video projectors. They
really were impressive and I would have liked to spend a lot more time watching
them – if only the sound had not been wound up to pain levels.
There were a significant number of turntables on display too, as further evidence
that vinyl recordings are going through something of a revival. It must be admitted that there is something quite satisfying about a playing a record. No, you don’t
press a button to select a track; it is a truly manual process as you position the
stylus over the start of the track and carefully lower it onto the record. CDs have
taken away that ritual.
For me, the JBL S-4700 3-way system with a 15-inch woofer, horn midrange and
horn tweeter was an ear-opener. It was quite efficient for a hifi speaker and was
driven by a relatively low-powered amplifier. Again, you can’t really make a fair
assessment in a small hotel room but it was impressive nonetheless and from a
cabinet which was not overly large at just over a metre tall.
This is really a throw-back to the past and quite a different approach from current tower-style speakers with relatively small diameter drivers of average or low
efficiency. With such a large cone area, a 15-inch speaker does not have to work
very hard to produce copious amounts of bass.
It got me wondering what we could possibly achieve with a do-it-yourself highefficiency 15-inch woofer. It should not be difficult to get a flat response down to
around 25Hz or so. In fact, it should relatively easy. It could be a real room-shaker.
And with high efficiency, it could be a very good match with our 20W Class-A
amplifier. For even more grunt, our Ultra-LD amplifier could drive such a speaker
to truly deafening levels, even in large lounge rooms.
Even a valve amplifier could probably do a reasonable job of driving it. OK, that
was probably a bit patronising but there is an element of truth to it. If a valve amplifier is not driven hard, it will generally have lower distortion, although nowhere
nearly as low as from a well-designed solid-state unit.
Leo Simpson
siliconchip.com.au
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