At the heart of any good home entertainment system is the amplification. But we have never been happy with just one speaker and even in the 1930's attempts were being made to get stereo sound. Even when that arrived commercially in the late 1950s with reel-to-reel tape and vinyl records, we still weren't satisfied but wanted still more and by the end of the 1960's the first quadraphonic systems were appearing. A number of factors - mainly lack of recordings - saw quadraphonic die off. But not entirely. Some devotees still played around with the idea and with the help of Ray Dolby and the movie industry Dolby Surround arrived. For domestic use, Dolby Pro-Logic was the start of a new beginning. At the same time, Yamaha in Japan were developing Digital Sound Processing (DSP) and sometime around 1987 released the Yamaha DSP-A1, a surround sound amplifier. This was hugely successful. But the North American market was conditioned to buy receivers - an amplifier with radio built-in - and so very quickly the home theatre or audio/video receiver arrived. Early models were very well made and many delivered high levels of performance.
This initial and in hindsight wise course to produce high-quality products gave confidence to consumers and has meant that today, 30 years plus later, home theatre receivers with their combination of multiple amplifiers and processing are the most popular way to experience immersive, theatre-like surround sound to your living room. It can also act as a connection hub for a variety of audio, video, and on many models, internet streaming sources. When combined with an outstanding picture this one component does almost everything.
Home Theatre Receivers - The Basics
Entry level home theatre receivers offer 5 channel output as illustrated by the Marantz model featured above. In other words you could connect 5 speakers - Left/Right Front, Centre and Left/Right Rear speakers. With the addition of a subwoofer this is still the most popular option and we call it 5.1 Surround Sound with the .1 referring to the subwoofer.
How Many Channels Do You Need? The numbers of channels a receiver has corresponds to the number of speakers it can power. You need at least 5 channels to get surround sound - Left/Right Front, Centre and Left/Right Rear speakers. However, most home theatre receivers are available as 7.1 channel models and that is what we usually recommend. Even if you’re starting with just a pair of stereo speakers, you can always add more as your budget permits. Plus, with a 7.1 channel receiver you can often expand your system into another room. In other words, you can enjoy 5.1 surround sound in the main room and have a pair of stereo speakers in a second room. There are also receivers with nine or eleven channels of power for even more versatility.
Input Connectivity: As mentioned above, a home theatre receiver is like a hub with signals going both in and out. Input devices can include a DVD player, Blu-ray player, pay TV/Cable box, Game console and Set-Top box or even other devices like a video tape recorder! These inputs plug into what is called the pre-amplifier. Most common connection today is called HDMI (High Definition Multi-Media Interface) and you need these for modern digital input devices. Our tip is to choose a receiver that has more HDMI inputs than you currently need because none of us know what is just around the corner when it comes to new technology or even what we may add in the near future. Most consumers who are upgrading cite that a lack of inputs was a major factor for a change.
Some older video devices use a connection called component but this is fast disappearing so check this before making a purchase. Analogue devices like a CD player or record player (Turntable) will plug into the line-level inputs which use the tried and tested RCA type connector.
Note: Not all home theatre receivers have a dedicated phono input and most that do only offer low-level performance. For that reason, there is a number of after-market phono preamplifiers that connect between the two.
How Much Power Do You Need? This is the most misunderstood area, can have as many variables as a Lottery ticket and is not easy to describe simply. It has a lot to do with you and your needs and these include (1) how loud you want to play your music or movies; (2) the size of your room and (3) the size or more accurately the efficiency of your speakers.
- Loudness/Volume: Over the years we have repaired more speakers than we can remember. The majority are "cooked" or more truthfully over-cooked by having been over-driven by the amplifier. The fact is, every amplifier or receiver will run-out of power and when this happens it goes into what is called clipping or distortion. This is often inaudible to the human ear but causes catastrophic damage in just a few seconds. Some consumers mistakenly think that the position of the volume control determines how 'hard' the amplifier is working. In other words the 12 o'clock position means half power. Wrong! Depending on the input level this may in fact be the full power output! The other point to remember is that the stated output is the maximum under optimum conditions. No matter how you try the amplifier will not output more. Conclusion? You must choose a receiver that delivers enough power output (volume) to comfortably satisfies your needs. By all means, give us a call for help.
- Room Size: Other than moving house or renovating there is not much any of us can do with the room size. What we have is what we have. However we can say with confidence that the smaller the room, the easier and cheaper it is to get enough power. Even if you have a healthy budget you do not need to spend it on more power. Better quality components will simply deliver better sound. However as the room size increases, so does the requirement for more power because it simply gets sucked up by the volume of air. To give an example, you need more paint to paint a larger room than a smaller one. Adding water to make the paint go further just doesn't work. Same with a receiver. You need more power for a bigger room...even if you are sitting close to the speakers.
- Speakers: The choice of speakers is like a marriage. The speakers and the receiver must complement each other for a succesful union. This does not mean they have to be the same brand. In fact the best speakers - with few exceptions - come from manufacturers who specialise in just speaker design. However when it comes to choosing a receiver you need to consider both the size of the speaker, its impedance and its efficiency rating which is given in decibels. These are three very important factors and all have to be considered together. The size of the speaker can affect power requirements, but impedance and efficiency have more of a bearing. Impedance is measured in Ohms and domestic speakers are usually 4, 6 or 8 Ohms. The lower the impedance, the less power you require for a given volume. This is neither good nor bad and there is no need to put a huge emphasis on this specification. The speakers are what they are but it is harder for an amplifier to 'drive' lower impedance speakers than higher impedance speakers. The other specification which is extremely critical is the efficiency or decibel (db) output. Speakers usually cover a range between 87db and 95db but there are a few exceptions that go either side of this parameter. The thing to note is that the lower the efficiency of the speaker, the harder the amplifier has to work but the trade-off is better bass. The converse is also true. The higher the efficiency, the easier it is for the amplifier but the trade-off is weaker bass. So aware of this, most manufacturers keep their speakers in the range of 90db to 93db which we often refer to as amplifier friendly. But if the speakers you really lust after are below these numbers it simply means you need a more powerful amplifier/receiver.
Note: If you are running 7 or 9 speakers either in surround sound mode or as part of a multi-room system, you may need to buy an additional power amplifier to drive the main front speakers. Also important is that you check closely the "official" specifications as some manufacturers are deceptive with their brochure specifications and will quote two different power ratings - usually enlarging the more impressive but essentially inaccurate specification. As you can see, understanding this can be a minefield for the novice because there are just so many variables. Naturally our staff can help.
Home Theatre Receivers - Special Features
So we've covered the basics and with that alone you are well equipped to choose a suitable home theatre receiver. But these "jack of all trades" are loaded with interesting features so let's take a closer look at some of them.
Multi-Channel Surround Sound Formats: As mentioned in our opening paragraphs, modern day surround sound got its start with Ray Dolby. The first home theatre receivers employed Dolby Pro-logic which had mono rears. Dolby Digital is the main format with DTS the other system and we don't know of a receiver that doesn't have at least the basic system. The following are the main multi-channel formats. Not all are on every receiver. Click on any of the links to learn more.
Note: Dolby Digital and DTS listening modes can only be selected if your audio source is connected to the receiver via a digital audio connection (HDMI, optical, or coaxial). To enjoy true 7.1/7.2 Channel Dolby Digital TrueHD and DTS-HD surround sound, the receiver must be connected to a Blu-ray player via HDMI.
Dolby Surround: Ray Dolby lives on and Dolby offers an enhanced cinema experience to your Dolby Digital (Plus/TrueHD) and DTS (ES/HD) movie soundtracks using your existing 7.1 Channel or Dolby Atmos speaker setup. Dolby Surround enhances audio definition by improving the spatial dimension and overall audio definition of movie soundtracks. It does this by using four distinct surround zones that provide greater control over the exact placement of each detail in a movie sound track, so audio can be matched more accurately to the video on screen; this means more depth and greater realism for your movies. As a result, individual sounds are clearer and more distinct. It also improves the surround sound experience across the entire theatre by widening the listening "sweet spot".
Dolby Atmos: Dolby founder Ray Dolby would be proud to see that his dream for the best sound lives on with Dolby Atmos. Indeed sound comes alive from all directions, including overhead to fill your home theatre with astonishing clarity, power, detail, and depth. Here's how it can be configured.
- A 5.2.2 or 5.2.4 speaker configuration is based upon a traditional 5.2 speaker layout complemented by 2 or 4 overhead or Dolby Atmos-enabled speakers.
- A 7.2.2 or 7.2.4 configuration is based on a 7.2 speaker layout with either 2 or 4 overhead or Dolby Atmos-enabled speakers.
- A 9.2.2 configuration is based on a 9.2 speaker layout with 2 overhead speakers.
- Ceiling Mounted Speakers: Ceiling speakers are used for maximising effects in Dolby Atmos listening mode. Install these speakers midway between the position just above the listening position and the position just above the front speakers, or simply install them just above the listening position.
- Dolby Enabled Speakers: There are two types of Dolby Enabled Speakers; one is to be placed on the top board of other speakers such as front speakers and surround speakers; the other is integrated within the front or surround speakers. Dolby Enabled Speakers are designed with their output facing toward the ceiling to create an elevated audio effect in the Dolby Atmos mode by providing sounds echoing off the ceiling.
Room Correction: All home theatre receivers have some form of automatic speaker calibration to ensure the best sound for your setup and room.
Multi-Room Audio: Would you like to listen to music in your bedroom or on your outdoor deck? Home theatre receivers with seven or more channels let you spread your music system into other rooms. With a 7 channel receiver, you can use 5 channels for surround sound and two channels for stereo speakers in another room. A 9 channel receiver can run extra speakers in two rooms. However, this can put an unwanted load on your receiver and will lower the power output to your main system if running all speakers simultaneously. Is there an alternative? Yes! Brands including Denon, Marantz and Yamaha offer proprietary technology that allows you to seamlessly add their active speakers which also operate wirelessly. If you have an older receiver, you can still add wireless speakers.
Multi-Room Video: Only the most expensive home theatre receivers offer a second HDMI video output. If this is important or you want to connect multiple TVs or projectors throughout the home, please call us to discuss your options.
Upscaling: And while we're talking video lets discuss the term upscaling.
Networking, Wi-Fi And Streaming: Many home theatre receivers have built-in streaming features. They let you play music from a compatible mobile device or computer. Or you can access online music services through the receiver's network connection. You’ll find plenty of options with some or all of the following features:
- Built-in support for popular streaming services like Spotify and Pandora. (A subscription is required for some services.)
- Bluetooth for streaming any audio from a smartphone or tablet and most computers.
- Apple AirPlay for streaming lossless audio from compatible iOS devices.
Subwoofer: These weren't always part of surround sound but George Lucas and his colleague Tomlinson Holman changed all that with the early Star Wars movies and a system called THX - Tomlinson Holman Xperiment.
3D Pass-Through: With the advent of 3D media, it is important to own a receiver that recognises 3D video signals. Being able to pass through 3D signals from your Blu-ray player or other compatible device ensures that the 3D effect doesn't get lost in translation. It also recognises signals from 3D television broadcasts. By connecting a 3D-compliant Blu-ray disc player and 3D-compliant TV to the home theatre receiver, you will have a 3D home theatre where you can enjoy high-definition sound and video at a very high standard.
ARC (Audio Return Channel): This feature allows audio to be sent from your compatible HDTV to your receiver through the same HDMI cable already being used to send audio and video to your HDTV. This eliminates the need for extra cables connected to your television.
4K/60Hz Pass-Through: The receiver's HDMI inputs and HDMI outputs support 4K/60Hz Ultra-HD, 4:4:4 Pure Color, and 21:9 video pass-through, a feature of the latest HDMI 2.0 specification for Ultra-HD content. They also support 1080p (24 or 60Hz) for playback of high-definition content from Blu-ray, Pay TV, and gaming devices.
4K Video Up-conversion: 4K video offers amazing picture quality. If you demand the best in picture, then you'll want a receiver that has a sophisticated video processor. It will also provide up-conversion from standard definition (480i/480p/576p) and high definition (720p/1080i1080p) sources to 4K Ultra HD (3840 x 2160 pixels), which lets you connect all your analogue (composite/component) or digital (HDMI) video sources to the receiver and then connect to your HDTV with just a single HDMI cable for amazing images. You will need a 4K capable TV.
App Control: Just about every home theatre receiver with network capability offers a free app to use your phone or tablet as a remote. They make it easy to switch sources, adjust the volume, tweak settings and stream music from online sources. Yes, all home theatre receivers come with a remote control, but unless you don't have a smart device, the free app is the way to go.
We Are Here To Help You Choose
Have questions about choosing the right home theatre receiver? Call us to have a chat about some of the products we recommend. Our experienced and expert staff know the gear inside and out and they can send specific product pages to your screen that meet your needs. Naturallly this will save you a lot of browsing time but minimise the hassle in choosing and the bonus is that you'll get a shopping cart loaded up with everything you need for your home theatre system. And that's not all as Audio Trends provides free lifetime tech support with your purchase.
Considering the power capacitance of amplifiers help with the power delivery, once the cap has discharged, it needs to be recharged; this takes time and power away from the output stage. Dependant on how much power is required the quicker the recharge the better the audio performance
The quick easy way for the novice to determine if the output of an amplifier is measured as 1 channel or all channels driven, look on the back panel of the receiver, for the power consumption requirements of the unit, this will give you a clear Watts required, in this case, generally the higher the number the better the performance.
This also relates to the number of channels the amplifier is driving 5.1, 6.1, and 7.1. An amplifier can rarely have too much power!
Beware not to confuse output with CONSUMPTION. Power requirements (consumption) of the amplifier will give an indication of its performance capabilities, not the output, as the specification sheets and marketing would have you believe. As a general guide, use it for all Amplifier devices, from MONO power amps to Stereo integrated receivers including multi channel units.