PS AUDIO: Image size

Paul McGowan … All stereo systems produce a sonic image—some better than others. But, regardless of the image quality, there’s one thing we can say they have in common: a size to that image. If you turn the level of the stereo down to a whisper there’s a tiny image trapped between the speakers. Crank […]

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PS AUDIO: Why flat?

When we look at the specs for a piece of audio equipment we want to make sure it doesn’t emphasize or reduce one frequency area over another.  We routinely see flatness specs that are within 1/10th of a dB from below where we can hear to way above where we hear.  These specs make us […]

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PS AUDIO: Class is now in session

Paul McGowan … Sorry about the headline, just couldn’t resist.  We are going to start delving into the working of Class D amps, also incorrectly known as “digital amps” and correctly labeled PWM amps – short for Pulse Width Modulation. As is our custom we’ll start with an overview and then get into details. It’s […]

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PS AUDIO: Surround ambience

Paul McGowan …. My friend, Sandy, is having good success adding a layer of ambience with a rear-positioned second set of speakers fed from an old Audio Research SDP1. You can read the late J. Gordon Holt’s evaluation of it here. Essentially, the device extracts the difference between the left and right channels, adds a bit […]

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PS AUDIO: Global feedback

When we speak of global feedback we’re referring to the practice of wrapping the output signal of a device back to its input for comparison and correction. Because the input “knows” what’s right, a simple comparison circuit between the two serves to rectify any differences. Of course, nothing in engineering is a free lunch. You […]

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PS AUDIO: Intermodulation

When we think about distortion products we are generally referring to the harmonic kind. Harmonics are naturally occurring byproducts of sound: a plucked string will generate the intended frequency (called the first harmonic) and then higher versions of that note, each slightly less loud than its predecessor. These higher frequencies are all integers (whole numbers) […]

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PS AUDIO: Ignorance and confidence

When we set our sights far in the future the world looks nice and rosy. Imagine that new pair of speakers gracing your living room, the new amplifier, the rebuilt room. According to Mark Twain imagining the future takes a combination of things. “Kindness is the language which the deaf can hear and the blind […]

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PS AUDIO: High voltage and linearity

In a recent post we covered the fundamental differences between tubes and transistors and one of those we’re interested in is linearity. Tubes and transistors are only partially linear devices – which means they will not always faithfully reproduce a larger version of the input signal on their outputs. In our example yesterday we placed […]

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PS AUDIO: Balanced is better

Paul McGowan writes … In my mind, there’s no question that between components the best connection is balanced. Balanced cables offer lower noise and better sound. I understand there are single-ended holdouts (wait, we disagree on something in audio?). Perhaps their equipment doesn’t support balanced. Perhaps their cable collection doesn’t include balanced. Or maybe they […]

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BURIED TRASURE

Linn’s founder, Ivor Tiefenbrun, wanted to sell turntables. He did this in the early 1970s by building a great product, certainly. But more than just a product, he threw a bit of wisdom into the high end lexicon that I believe has had more of an impact than anything else I can think of. The […]

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