AV receiver shopping guidelines
Chances are pretty good that an AV receiver is amongst the audio visual items present at your home. Said AV receiver these days is packed with advanced technology and features that all carry some abbreviated letter name of some sort. Many of us will have to admit, half of the time that fancy letterword may as well be mumbo jumbo. You can relax, it’s not you.:-)
But when it’s time to upgrade and with every supplier screaming how they’re the greatest thing since sliced bread, how do you make any sense out of that? I mean confusion reigns, no?
Worry not. A few weeks ago, Digital Trends published a very comprehensive guide for picking an AV receiver. We thought it was an excellent summary of some of the newer terminology, 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 visiting a showroom. In true Rapallo style, we like to do some adjusting, rewriting and can’t help ourselves from throwing in a comment of our own here and there. The US is not New Zealand after all.
So, let’s get started.
STEREO OR SURROUND?
So to start with, we’re talking about AV receivers as opposed to stereo receivers. While there are many similarities between the two, stereo receivers are designed to operate two speakers at a time and usually offer a phono input, but things like subwoofer outputs, digital audio inputs and digital music delivery remain inconsistent on stereo receivers, but that is changing.
AV (audiovisual) receivers on the other hand are intended to function as the core of a home theatre. They offer surround sound capability, digital audio processing, digital video processing and switching, automatic speaker setup systems and, more commonly, network audio and video support.
So while we’ll be chatting about AV receivers, it’s good to note that many of the characteristics that indicate product quality actually apply to both.
SPECS: USEFUL OR MISLEADING?
Today’s AV 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 find a way to get a grasp on some level as to what is an options for your specific needs and desires.
A good place to start is product specifications (specs), so you can get an idea of what does or doesn’t tick the boxes. Specs, though, can be highly suspect, as you’ll see. Sigh!
We’ve talked about this in previous blogs, but the sad truth is that manufacturer specifications are not as indicative of product quality as they once were. Many of the big wellknown 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 and audiophile brands like Arcam and Emotiva don’t tend to dabble in this game as much, most big-name brands do to some degree. For example: Have you noticed that almost everything pushes 100 Watts per channel these days?
The good news is that 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.
POWER
We need to do some explaining on this topic. Yes, this is where most of the deception takes place. Manufacturers know buyers are looking for big numbers when it comes to amplifier power ratings, 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.
To get an accurate idea of the real power rating of an AV receiver, the trick is to look for RMS power for all channels driven @ 20Hz-20KHz at 8 Ohm load (or 6 Ohm if that’s what your speakers are).
We explain:
RMS: Power should be expressed as RMS and not peak power. Sometimes you’ll also find RMS referred to as Continuous Power Output. Peak power (as opposed to RMS) could mean the receiver puts out X watts for well under one second. 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.
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.
BUT, to put things in perspective, we would like to tell you not to get too hung-up on AV receiver power ratings. We know it’s a thing that has become this massive point of selling, but in the end, there’s not a lot of difference between 100 watts and 120 watts, or 80 watts and 110 watts. All else being equal, small increases in power ratings do not represent much of an upgrade. The reason for this is that to have and increase in 3db you need to double(!) your amplifier power. Most AV receivers sit between 80 to 140 watts. The difference between the higher end and the lower end of this spectrum will be minimal. It’s good to remember that other things will influence the sound much more than power ratings. Signal-to-noise ratio, damping factor, quality of power supply, supported formats, inputs & outputs are all very important considerations.
Bottom-line: if you are driving 8 Ohm speakers, there aren’t many of the AV receivers you can go wrong with as far as power ratings go on the condition that you don’t intend on driving 9 or 11 channels at full blast. It’s when you are looking at 4Ohm speakers you need to make this a much bigger consideration.
All the big brands tamper with power ratings to some extend. If you see any of the warning signs of blatant 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 (a DAC matter)
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. Talk to any audiophile and they’ll be able to tell you entire story’s on what makes a good DAC. 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.
Arcam AV receivers for instance boast a Cirrus CS42528 audiophile DAC, while the high-end Yamaha Aventage AV receivers (like the brand new Yamaha Aventage RX-A3080) show off with an ESS SABRE PRO ES9026PRO Ultra DAC and SABRE ES9007S DAC, all very reputable DAC chips.
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 the specific mention 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 8Ohm 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. 4 Ohm speakers are typically high-end speakers, but some of our best-selling speakers like the ELAC Debut 2.0 Series and the Q acoustics 3000 series are 6 Ohm speakers.
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 (including the ones that are sold by Rapallo) 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. Considering that subwoofers tend to be self-powered, the use of a subwoofer lifts a lot of responsibility from the receiver. Just another reason why the use of a subwoofer is a good idea.
Systems that use a 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.
SURROUND SOUND SUPPORT
5.1, 7.1, 7.2, 9.1, 11.2 …
For a home theatre that goes beyond the soundbar, Dolby Digital 5.1 is an absolute must. Our experience is that in New Zealand, 7.1 or higher is relevant to people who are really serious about their home theatre and have a room (dedicated or not) that is large enough. Slowly but steadily, our New Zealand customers are taking on Dolby Atmos and DTS:X, so if you intend on future proofing and considering height channels in the future, you should take this into account.
AUTO-CALIBRATION SYSTEMS
Most mid- to high-level receivers come with some form or another of an auto-setup tool for speaker setup and calibration. Auto-calibration is a very polarizing subject with some people absolutely swearing by it, while others don’t even want to hear the word.
Our experience is that it would be simplifying things unfairly either way to put all calibration systems under the same ‘good’ or ‘bad’ umbrella. We’ve seen some amazing ones that are a very useful tool without a doubt, and we ‘ve seen some horrific ones that are a curse rather than a blessing and we wouldn’t go near them, even if we were paid to do so.
Bottom-line: if auto-setup is appealing to you, be sure to read our blog on calibration systems, which you can find here.
CONNECTIVITY: CONVENIENCE AND FUTURE PROOFING
With some of the more technical stuff dealt with, let’s start digging into the features and functions that make an AV receiver so fun and convenient. Again this is a massive selling point and it’s good to clear up what is useful and what is just an impressive sounding name on a spec sheet.
We’ll start with the ins and the outs, otherwise known as connectivity. The Digital Trends article has an extensive list with terminology here that covers anything from HDMI to Bluetooth and anything in between. While this extensive list definitely has its use, It’s making our blog a marathon exercise and nobody in his right mind will read through the entire thing, we figure. So we’ve just summarised the important bits as we assume you know what Bluetooth is by now.
So here’s what you have to take from all the terminology as far as Connectivity is concerned:
These days we’re up to HDMI2.0a, the latest version that supports 4K Ultra HD and high dynamic range (HDR) as well as older technologies like 3D video, Audio Return Channel (ARC), and Ethernet over HDMI. We recommend choosing a receiver that has a few more HDMI inputs than you presently need so that you have room to grow your system.
Some things that are worth having are:
The Digital Trends article talks about HDMI Standby Pass-Through as a slick and pretty useful feature. It will send any connected HDMI signal out to your TV even if it is turned off. This way, you can still watch TV from connected sources without necessarily having your receiver turned on or the sound coming through your speaker system. It’s pretty standard on most AV receivers these days.
In a typical system, the receiver sends information “upstream” to the TV, feeding it with picture and sound information. Occasionally, though, you might want to send audio information from the TV “downstream” to the receiver. Let’s say you were watching local HD TV or something from your TV’s Internet apps; ARC (Auto return Channel) allows the audio signal from the TV to be sent to the receiver so it can be processed and played back over your audio system. Bart has this to say on the topic: ‘You probably want this, but compatibility between brands can be a challenge. Always make sure you have a plan B in having an optical in as well. ‘
An Ethernet connection allows for your receiver’s firmware to be easily updated. Bart likes it for internet radio or Spotify because it is more reliable than Wi-Fi.
DLNA stands for Digital Living Network Alliance and is a standard set up to make sharing pictures, music, and video among digital devices easier. The feature allows access to digital files on any computer in your home network (provided sharing is turned on) According to Bart, this is a nice to have for ‘computer people’. For everybody else, it’s not much use because the user interface tends to be not as user-friendly as one would like.
And then there are a few bells and whistles that might as well not take up any space on the spec sheet. Ignore, we think.
We’re talking about Satellite radio (Sirius) which is very much for USA people, not for New Zealand. Nobody we’ve encountered in NZ uses Sirius.
Also ignore Video upscaling, which in Bart’s book is looking for trouble: very few brands do it well (Darbee being an exception) and it tends to come with lots of artefacts. He thinks it’s just not worth the effort.
DISTRIBUTION: SERVING UP OTHER ROOMS
The whole topic on multi-room is absolutely relevant to AV receivers, but it’s also whole discussion in its own right.There are a few things to look out for.
Most receivers do allow for listening to one source in the main room and a separate source in others. However, it is not always clear whether the receiver will play a digital source in the second or third rooms. This is something you need to look into, because requiring an analog source for zone 2 and 3 means running extra cables to your components, and that is not always something self-installers are interested in doing. There’s another caveat to multi-zone support…
Many receivers make one or more of their surround channels “assignable” in order to send amplified sound elsewhere. This means you may have to do without a couple of surround speakers if you want to run audio to another room.
We recommend checking with your retailer to make sure your AV receiver does all the things you want from it. They should know their products and be able to guide you through the multi-room minefield.
And then it is time to put your short-list to the test. Feel free to talk to us, pop into our showroom. We have Yamaha, Yamaha Aventage, Emotiva end Arcam on demo. These are Rapallo recommended brands that cover a good range of needs and budgets. When you visit the showroom for your demo, we will discuss your budget, desires, other AV products that are already part of your set-up and your (future) needs with you. We are more than happy to take you through a demo so you can get an idea for yourself what a specific AV receiver sounds like and your decision is a well considered and informed one. After all, when you spend that amount of money, you want it to go to the best possible product for you.
Photo from Arcam