SONY V-FET (July 1977)

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V-FETs are the new generation of transistors.

And you know how hard it is to understand the new generation.

Remember the phrase "generation gap"? Well it's not only true for generations of men, but generations of machines, too.

V-Fet devices are a major advancement, needing major explanation. And nobody is more equipped to offer it, than Sony.

Sony pioneered the first generation of transistors, some 25 years ago.

Today, Sony is predictably innovative again, being: the first to offer V-Fet equipment commercially. And the only ones to bedazzle you with a whole line of it.

So with these credentials behind us, we will begin our explanation of the new generation.

First came the Fets.

The new generation really began many generations ago.

Fets-or field effect transistors were first conceived in the 1920's.

But the concept was so far ahead of its time that nobody quite knew how to execute it.

Fet's work quite differently than the bipolar transistor; the transistor you're familiar with. The bipolar transistor works by conducting a small amount of current, which then induces a high level of current.

With the Fet a small amount of voltage (rather than current) controls the high level of current.

This bestows a Fet with high speed reaction time. Regular transistors have a delay in reaction time, creating problems like notch distortion and TIM (transient inter modulation) distortion.

This high speed reaction means also that Fets are extremely efficient and accurate in the high frequency range. Therefore they allow more precise and stable negative feedback, and minimal distortion.

And, to heat up the argument, a Fet will never be afflicted by thermal runaway. High temperature does not induce the self-destructive current surge that you'll find in the regular transistor.

V Fets. Or, bye, bye, bipolar.

Wondering why Fets have not taken over, with the transistor becoming a part of history? Well, for one reason, a Fet will not allow high currents to pass through it. And today's loudspeakers demand high currents to drive them.


Harmonic distortion components. Conventional Transistor The wave of the of the past future.

Transistor switching lag. | The lack of lag with V Fets. One reason nearly everyone will be switching to V-Fets


Enter the V-Fet. Vertical field effect transistor. In this structure, thousands of Fets are ordered in a parallel orientation. The current passes through the silicone chips vertically.

Thus the ability of the V-Fet to handle a lot of current is many times greater than that of small signal Fets-like the kind found in FM tuners and pre -amps.

Sony made it possible for this complex network to be mass produced, by devising the "Selective Oxidation Process" A new technology originally developed for manufacturing large scale integrated circuits.

Sony's V Fets. A fall line, from A to V.

Sony makes both integrated amps and power amps with V-Fet circuitry. The TA-4650, TA-5650, TA-8650, TAN-5550 and TAN -8550. But if you rest your purchase decision on specs alone, V-Fets will disappoint you.

For example, Sony makes two amps, one V-Fet, one not, with identical specs. Yet the V-Fet amp costs more than a spec more.

Obviously, the true measure of V-Fets can't be measured by anything except the human ear.

Now that you've listened to us, really listen to us.

So go ahead and measure it! Bring your favorite record to your V-Fet dealer. Ask him to play it.

You'll find your favorite record will become even more of a favorite, as the sound opens up to you like never before.

And, if you want to open up a brochure on V-Fets, we'll send you one. Write to:

SONY, 9 West 57th Street, New York, New York 10019.

We have one note to add. V-Fet equipment is not cheap. So if you've appreciated our explanation, you'll find that a little knowledge can be an expensive thing.


(Source: Audio magazine, July 1977)

Also see: Sony V-FET (Mar. 1977)

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Updated: Tuesday, 2018-02-20 8:42 PST