There are a number of reasons it may be time to purchase a new audio receiver. Did you buy the receiver you currently own when Bill Clinton was still in the oval office? Did you recently pick up a Blu-ray disc player capable of supporting some cool sounding high-resolution audio formats? Did you just get the green light to build that man cave you’ve been dreaming about? If you answered yes to any of those questions, picking up a new receiver is probably an excellent idea.
Here’s the good news: Today’s receivers are packed with lots of advanced technology and just plain cool features, now offering better value than ever before. Here’s the bad news: Today’s receivers are packed with lots of advanced technology and just plain cool 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, highlight some of the newest features and explain what to look and listen for when auditioning. When you’re done reading this guide, you’ll be armed with the information you need to make a solid buying decision on a receiver that will serve you well for years to come. Let’s get started.
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, and some sort of iPod integration available with the purchase of an optional iPod dock. Subwoofer outputs can occasionally be found on stereo receivers, but are not common. Stereo receivers rarely support video or digital audio inputs, favoring analog stereo instead.
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.
We should note that stereo receivers are far less popular today than they used to be, but they can be a great fit for those whose primary use will be stereo music, or for use in smaller rooms like offices and bedrooms. They can be used to enhance the TV experience as well, but don’t expect a stereo receiver to make the task of coordinating several sources (cable or satellite box, DVD, Blu-Ray, DVR, game consoles, etc.) with your TV any easier.
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.
Getting good sound
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.
Specs: Useful or misleading?
The sad truth is that manufacturer specifications are not as indicative of product quality as they once were. Many of the companies that make receivers have figured out how to “cook the books” to make their products look attractive, even if they sit at the bottom of the product line. While high-end brands don’t tend to dabble in this game, most big-name brands do to some degree. Have you noticed that almost everything pushes 100 watts per channel these days?
Still, it is possible to read between the lines and get a better idea of whether a given receiver is worth further investigation, or should be cut from the list of contenders right away. Here’s our explanation of some crucial specifications and clues on what to look for.
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 and not peak power. Peak power could mean the receiver puts out X watts for well under one second. RMS (root mean squared) refers to continuous power that can be sustained for long periods of time, and is a more revealing indication of power capabilities.
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 amongst 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 receivers 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 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.
If you see any of the warning signs of wattage rating fudgery, we recommend you just move on to other options, since it is likely that other disclosures are less than forthright as well.
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, 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 an as 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 oompf.
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 speakers live between 85dB and 95dB per watt, with some exceptions on both ends of the spectrum. If your speakers live on the low end, plan on a higher-powered receiver to get them performing their best. Keep in mind that sensitivity is not an indication of sound quality. It just means it can play louder with less power.
Bandwidth: Generally speaking, the more bass you demand from your speakers, the more power you will need to feed them. The introduction of the self-powered subwoofer has lifted a lot of responsibility from the receiver. Systems that use smaller bookshelf or satellite speakers and leave the earth-shaking task to the subwoofer, require a little less power from the receiver. Those who employ full-range speakers that produce a lot of bass will probably need more power. There are exceptions, though. Highly sensitive speakers tend to put out plenty of bass with less power. Yet another reason to look at your speakers’ sensitivity.
For more information on choosing speakers, check out our speaker buying guide here.
Surround sound support
5.1, 7.1, 7.2, 9.1, 11.2…While it is a foregone conclusion that an A/V receiver will support some manner of surround sound, the surround sound formats it can handle are still an important consideration for receiver buyers. Surround sound options have advanced considerably in recent years and the topic is…well…involved. So involved, in fact, that we wrote a separate guide dedicated to it, which is posted here.
Most mid- to high-level receivers come with some form or another of an auto-setup tool for speaker setup and calibration. While we concede that these tools can be quite useful for those intimidated by their receiver’s user menu, we maintain that they run a distant second to a manual calibration. If auto setup is appealing to you, be sure to read up on which systems work well and which don’t. In any case, we recommend you check out our home theater calibration guide so that you can do the job yourself and do it better.