How to choose and buy an A/V receiver

Did you recently pick up a 4K TV and Ultra HD Blu-ray player and realize your trusty old A/V receiver isn’t compatible with it? Are you finally building out the home theater of your dreams? Here’s the good news: Today’s receivers are packed with lots of advanced technology and just plain cool features that offer better value than ever before. Here’s the bad news: Today’s receivers are packed with lots of advanced technology and features, making the research and buying process potentially more confusing than ever before.

Worry not. This guide to picking a receiver will get you up to date on some of the newer terms, demystify some of the specifications and ratings numbers you’ll be looking at as you research, and explain what to look and listen for when auditioning. Let’s get started.

Check out our A/V receiver reviews for a more in-depth look at what the market has to offer, as well as our picks for the best A/V receivers.

Stereo or surround?

Two basic categories of receivers exist: Stereo and A/V. A stereo receiver is designed to operate two speakers at a time, sometimes in multiple rooms. Today’s stereo receivers will often feature XM or Sirius satellite radio capability and HD radio tuners, in addition to traditional AM/FM tuners. They usually offer a phono input for listening to your record collection and some sort of smartphone integration available via Bluetooth or a USB connection, and sometimes support high-resolution audio over the latter. Subwoofer outputs remain inconsistent on stereo receivers, but that is changing. The same goes for digital audio inputs: In the past, they’ve been rare, but the trend toward digital music delivery has receiver makers almost always including some kind of digital input.

A/V (audio/video) receivers are intended to function as the core of a home theater. They build on the stereo receiver concept by adding surround sound capability, digital audio processing, digital video processing and switching, automatic speaker setup systems and, more commonly, network audio and video support.

Most stereo receivers these days are in the form of smart Bluetooth speakers, except for some dedicated or retro steups. For the most part, we will be focusing our discussion on how to choose an A/V receiver, but keep in mind that many of the characteristics that indicate product quality apply to both.

Specs: useful or misleading?

Today’s A/V receivers — even the budget models — are packed to the brim with all kinds of bells and whistles. But what good are fancy features if the receiver doesn’t sound good, right? With so many makes and models on the market, you need to weed out the bad units right off the bat. Otherwise, you just might go crazy trying to keep them all straight. To sort out your short-list, you can start by looking at some product specifications (specs) to get an idea for what you do and don’t want to spend your time auditioning. Specs, though, can be highly suspect, as you’ll see.

Some specs are more reliable than others, and certain specs can be faked or made to sound more important than they are. Sometimes manufacturers “cook the books” so they can put impressive-sounding blurbs on the box. That’s why we’re going to take each spec category at a time and go over what you should watch for.

Power

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This is where most of the deception takes place. Manufacturers know buyers are looking for big numbers, since it is commonly assumed that more watts means more power and, therefore, better sound. So, they’ve figured out ways to achieve the numbers that look good to buyers by making the tests less stressful. If the test is super easy, then everyone can get an “A,” right?

Fortunately, the FTC mandates that testing conditions be disclosed. So, with a little know-how, it is possible to differentiate a legit power rating from one that has been fudged. The key is to look at those testing condition disclosures.

RMS: Power should be expressed as RMS  (root mean squared) and not peak power. Peak power could mean the receiver puts out X watts is short bursts. RMS (root mean squared) refers to the continuous power that can be sustained for long periods of time, and is a more revealing indication of power capabilities. This is important when pairing speakers to your receiver (more on that below). A pair of speakers will often show its power handling, in watts, with two numbers. For example — 150/600, where the 150 is the limit it can handle continuously (this is the RMS), and the 600 being the peak watts the speakers can handle in short bursts.

All channels driven: A lower quality receiver might claim to output 100 watts per channel (WPC) in stereo mode, yet the rating will fall considerably (80 WPC or less) in surround mode. This indicates that one amp’s power is being split up among several speakers, and that usually results in poor power availability when you need it most. Instead, look for the statement “all channels driven,” which indicates amplification is equal to all of the receiver’s channels.

Bandwidth: A high power rating might also have been attained by driving a single frequency for a short amount of time. If you see 100 x 5 (@ 1kHz), this is a sign that the receiver’s power ratings were achieved under low-stress conditions and the rating on paper is much higher than what the receiver can pull off in the real world. Look for (@ 20Hz-20kHz) as an indication that the receiver was rated while driving a full-range audio signal to be sure the rating is accurate.

Impedance: Impedance is a measure of electrical resistance. Most (but definitely not all) home audio speakers have an impedance around 6 to 8 ohms. Manufacturers know this is the case, so they should publish power ratings established while driving an 8-ohm load. However, since power ratings can as much as double when established by using a lower impedance load, some receiver makers will use this to make their power ratings look better. Ironically, these receivers are nowhere near capable of driving a 4-ohm speaker in the real world. In fact, trying to do so will probably result in speaker and receiver damage. Bottom line, if you do see a 4-ohm power rating, there should also be an 8-ohm rating right next to it.

Total Harmonic Distortion (THD)

While power ratings are a valuable indicator of a receiver’s capability, they don’t tell the whole story about its sound quality. The THD rating can help round out the picture as it describes how faithful the sound signal remains to the original as the receiver amplifies it. THD less than 0.1 percent is considered to be inaudible, and 0.08 percent or lower is certainly very good. On the other hand, if you see anything higher than 0.1 percent, you can bet that the wattage ratings are way overblown. In that case, steer clear.

Processing (Choosing a DAC)

So far, we’ve dealt with identifying quality amplification in a receiver. Now, we need to look at the signal the receiver will be amplifying. As you can imagine, if the signal the receiver gets is poor, the resulting sound will be poor too, no matter how good the amp in a receiver is.

DAC stands for digital-to-analog converter. As the name implies, it takes the digital signal from your Blu-ray, DVD, game console, DVR or what-have-you, and converts it to analog so that it can be amplified. The better the DAC, the better the sound. So how do you know if a receiver uses quality DACs?

Most receiver manufacturers won’t bother to disclose the type of DAC in their products unless it is pretty good to begin with. If they are calling attention to the DAC maker (be it Burr Brown, ESS, SHARC or otherwise) there’s a good chance it is a quality DAC.

The fact that the name of the DAC isn’t listed in the specs guide doesn’t mean that the piece is of poor quality, though. You can just use its inclusion as an indication that the receiver is a little ahead of its like-priced competition.

The Matching Game: Getting your receiver and speakers to play nice

Getting great sound from your system requires that you match up your speakers’ needs with your receiver’s capabilities. Now that you know how to identify what a receiver can do in terms of power and processing, consider what your speakers need to sound their best. To do this, we’ll need to look at some speaker specs.

Impedance: As we mentioned before, your speakers’ impedance is the level of resistance that that is given to your receiver’s signal. An 8-ohm impedance rating is pretty typical, and speakers with this impedance play nicely with a very broad range of receivers. Once that number starts to drop, though, you will need more and more stable power. For example, 4-ohm speakers are tough to drive and will require an amplifier with more oomph.

Sensitivity/SPL: Your speakers’ sensitivity refers to how loud they play per given watt of power. The resulting SPL (sound pressure level) is noted in terms of dB (decibels). A speaker with low sensitivity will need more power to make it play as loudly as a speaker with high sensitivity. Generally, most speake

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