The Audio Classics' Newsletter
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Greetings!
What’s the Story with Meters in Home Audio Playback Systems?
By Howard Kneller
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Analog VU meters with bouncing needle displays have long been present on audiophile components, particularly amplifiers and tape decks. Think of the 1970’s and 1980’s vintage gear made by companies such as McIntosh, Audio Research, Luxman, Nagra, Phase Linear, and Accuphase. Simply stated, VU meters indicate the average level of an audio signal and provide an indication of perceived loudness. As McIntosh explains on its website, its familiar blue-panelled amplifier meters protect speakers from overload by “allow[ing] the monitoring of sound level balance and output level . . . .”
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Interestingly, Pass Lab’s founder, Nelson Pass, states that the needle display meters on his company’s amplifiers are different than most since they show the amp’s current consumption. According to Pass, since the electricity consumed by Pass Lab’s circuits is fairly high at all times, their meters never go to zero as do others.
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The first VU meters, which borrowed the needle display from voltmeters, were the product of a joint effort by Bell Labs and the CBS and NBC broadcasting companies. Designed to adhere to the then popular “volume unit” standard, they were assigned the “VU” moniker. Cheap to manufacture, although often not extremely accurate, these meters were introduced in the US around 1939 to maintain proper levels during radio broadcasts and in early telephone systems. Even today, VU meters are extremely useful, if not essential, for professional recording applications as they can be used to avoid overloading, noise, and distortion.
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But back to 1939. Due to the VU meter’s design limitations and disagreement concerning the technical underpinnings of the volume unit standard, BBC engineers across the pond quickly began referring to the VU meter as the “virtually useless” meter, instead preferring a much more complex meter developed a few years before the VU meter, called the peak program meter (PPM). Virtually useless meters are not to be confused with UI meters, which are jokingly referred to by many engineers as those that are “usually ignored.”
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Like VU meters, PPM meters indicate the level of an audio signal. However, in simplistic terms, while a VU meter displays the audio signal’s average level, a PPM displays its peak volume. Suffice to say here that while both types of meters perform the same function, they do so very differently.
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Beginning in the 1970s, VU meters from companies such as Sony, SAE (Scientific Audio Electronics), Yamaha, and Soundcraftsmen began using LED and plasma-based bars that move up and down or side-to side before at least temporarily retreating. Although those futuristic looking meters show signal level in a different way than do needle displays, they express the exact same information.
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Today, a growing number of VU audio meters, including ones used by companies such as Aurender and SAE, portray a digital rendering of an analog needle display. They exist only on an AMOLED or other type of display and disappear when the display is turned off.
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That’s not to say that analog needle display VU meters have been abandoned. Quite to the contrary, Mcintosh, Audio Research, Luxman, Nagra, Accuphase, Yamaha, and many other manufacturers still prominently use them, with the most iconic perhaps being those found on McIntosh’s components. The analog VU meter needle displays on Dan D’Agostino Master Audio System’s components, aesthetically inspired by Breguet and Tourbillon watch faces, are arguably the most gorgeous.
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There are other types of meters in home audio as well. In order to monitor tube bias, some components contain meters that indicate the DC balance status of the component’s output stage. Further, some power distributors and conditioners contain ammeters, which measure electrical current in amperes.
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For those who find themselves sans meter, VU meter kits and finished ones, many freestanding and quite large, are widely available at places like Ebay. While some of these aftermarket meters are classic in appearance, others are quite blingy. There are even downloads and mobile phone and desktop apps that can be used to turn a computer or phone display into a VU meter.
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Although there seems to be widespread agreement that VU meters are essential on certain types of professional recording gear, their utility for home playback systems is, like a lot of audio topics, the subject of debate. Some audiophiles state that if you blow your speakers, the fact that VU meters simultaneously peak into the danger zone won’t provide you with much opportunity to turn things down.
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Others agree with the statement on McIntosh’s website that, when monitored, VU meters are useful for monitoring purposes to help protect speakers from overload. They also state that ammeters are useful to determine whether an AC line is being overly taxed, thus alerting to the possible need of one or more additional lines. Of course, it can’t be disputed that presence of one or more meters seem to make an audio component come alive.
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Despite any controversy, one thing is clear: the addition of meters on home audio playback gear is almost always good for business. As the head designer of one manufacturer recently told me, sales of one of his components increased exponentially after he added a meter. As a result, it’s safe to assume that for many audio companies, meters won’t be going anywhere soon. Long live the meter!
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Howard Kneller is an audio reviewer, writer, and photographer whose work has appeared in such publications as the SoundStage! Network and Sound & Vision magazine. His audio and art photography can be found on Instagram (@howardkneller, @howardkneller.photog) and Facebook (@howardkneller).
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McIntosh
MC2301 Mono Block Amplifier
From the demands of massed chorale to full-on rock and roll, the MC2301 delivers the most extraordinarily lifelike and dynamic performance ever heard from a McIntosh tube amplifier. With an output of 300 Watts, it provides enough high power to drive even the most demanding loudspeaker. And thanks to our patented Unity Coupled Circuit output transformer, this full 300 Watts is available to 2, 4 or 8 Ohm speakers.
The MC2301 is the first McIntosh vacuum tube amplifier to use our Quad Balanced design. This design cancels virtually all noise and distortion in the audio signal. As a result, even when amplified to high levels the signal is effectively free of any distortion. Our fuse-less short-circuit protection circuit Sentry Monitor™ disengages the output stage before current exceeds safe operating levels and then resets automatically. Inputs for balanced and unbalanced cables are available to provide flexibility in connecting the rest of your audio system.
The attractive blue meter is flanked by two rows of output vacuum tubes that bring even more visual appeal to the front panel to go along with the knobs and brushed aluminum handles that all effortlessly blend with the polished stainless steel chassis. The MC2301 is well suited for stereo music systems. Contact Audio Classics to learn more.
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McIntosh
MA5300
2-Channel Integrated Amplifier
The MA5300 Integrated Amplifier is proof that big sound can come in small packages. It is our smallest solid state integrated amplifier in terms of both power output and physical size, making it an ideal choice for smaller spaces or for someone just beginning to assemble a home audio system. It’s a direct coupled amplifier that delivers 100 Watts per channel into 8 Ohm speakers or 160 Watts per channel into 4 Ohm speakers. New dual scale blue Watt meters give an accurate readout of power output for both 4 and 8 Ohm impedances.
The MA5300’s complement of 12 inputs includes 6 analog inputs (4 unbalanced, 1 balanced and 1 Moving Magnet input for turntables) and 6 digital inputs (2 each coaxial and optical, 1 USB and 1 proprietary MCT for use with our MCT series of SACD/CD Transports). All digital inputs are housed in our DA1 Digital Audio Module which can be replaced by future modules as new digital audio technologies are developed. (NOW AVAILABLE: Optional dealer installed upgrade to the DA2 Digital Audio Module.) The DA1 comes with an 8-channel, 32-bit Digital-to-Analog Converter (DAC) used in Quad Balanced mode and supports up to DSD256 and DXD 384kHz for high resolution audio playback. All inputs can be given user-friendly names to simplify system control and configuration. Included on the MA5300 are our McIntosh Monogrammed Heatsinks™ which are connected to advanced high current output transistors that eliminate warm-up time so you can enjoy the MA5300’s complete sonic capabilities from the moment you turn it on. Powerful new control microprocessors have been used to improve overall system operation, along with some of the latest audio-grade circuit components to deliver the best possible sound. Bass and treble tone controls have been added to help you further fine tune your music to your personal preferences.
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Have you been eyeing a new component but were unsure of what to do with your existing ones?
Now with the Audio Classics TradeUP Program, there's an easy way for you to upgrade to a current model without having to pay full price or having to deal with the hassle of selling your existing components. Simply trade in your qualified mono or stereo amplifier, preamplifier, integrated amplifier, tuner or receiver and get up to 75 percent of the price you paid for it towards the purchase of a new amplifier, pre-amplifier, integrated amplifier or receiver.
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Get in Touch Today!
Audio Classics, Ltd.
3501 Vestal Road
Vestal, NY 13850
Telephone: 607-766-3501
800-321-2834
Hours: M-F 8 a.m.-5 p.m.
Saturday by appointment only
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