AVR . ... you know some sort of a buying guide thing.... This could help newbie or others ..when they are trying to buy something for the first time.....
The Home Theater receiver, is the heart of a home theater system.
A Home Theater Receiver combines the functions of three components
1.
A tuner
2.
A Preamp that controls which audio/video source is selected , processes the incoming stereo/surround sound signals, and distributes audio to the channels and subwoofer output. Video from components are routed to a Display/TV.
3.
A built-in Multi-channel amplifier (5.1, 6.1, or 7.1 channels) that sends the surround sound signals and power to the speakers
HOW TO DEMO A HOME THEATRE RECIEVER(Without getting much into technical jargon)
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1)
Budget:-
The starting point is the amount you want to spend. Yes, its possible to get better amplifier in a limited budget also. Mostly 5.1 channel receivers are less costly than 7.1 channel receivers.
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Main Decision Making Factors:-
Decide accurately based on these points carefully, Take All Factors Into Consideration,:-
(a)
Power Ratings (WPC):-
AV receiver, always lists the Watts-Per-Channel rating. One receiver has 50 Watts-Per-Channel (WPC), another one has 75, and still another has 100.
The more watts the better right? Not Necessarily
An amplifier with 100 WPC is twice as loud as 50 WPC right? Not exactly
An amplifier rated at 100 WPC is capable of twice the volume level of a 10 WPC amp, an amplifier rated at 100 watts per channel needs to be 1,000 watts per channel to be twice as loud. In other words, the relationship between volume and wattage output is 1 to 10 rather than 1 to 1.
Power Spec at full bandwidth, 20 Hz to 20 kHz and at 1kHz:
Full disclosure specs will show power specs over the entire 20 Hz to 20 kHz audio range . Sometimes power is spec'd only at 1 kHz, or worst. When a receiver company rates their amp at 1kHz, this usually means a full bandwidth measurement of power will be about 10-15% lower, i.e power rated 95 WPC @1Khz could be only 75-80 WPC over the entire 20 Hz to 20 kHz audio range.
(b)
Distortion (THD):-.
Amount of change in harmonic content of the signal as it is amplified..It is measured in percentage terms, where the percentage represents the amount of distortion present in the audio signal at full output level. It consists of all the nonlinearities in the signal, which may or may not be harmonically related to the input signal, plus noise. A lower figure indicates less change and a more accurate amp. Most receivers are rated at 0.9% or lower,the lower the better.
You are better off with a receiver of about 50 WPC with a low distortion level than a more powerful amplifier with high Total harmonic distortion levels.
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Signal-To-Noise Ratio (S/N)
Another factor is Signal-To-Noise Ratio (S/N), which is ratio of sound to background noise. The larger the ratio, the more the desirable sounds (music, voice, effects) are separated from acoustical effects and background noise. In amplifier specifications S/N ratios are expressed in decibels. A S/N ratio of 100db is much more desirable that a S/N ratio of 70db.
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Features worth to have now a days:-
More advanced functions to consider when buying a Home Theater Receiver, such as Multi-Room Audio, iPod, Networking, and HD HDMI Audio/Video Connectivity, HD sound decoding, Matrix feature to up-mix 5.1 channel sound sources/tracks to 7.1 for 7.1 speaker setups/recievers (this feature is most sought after by many)
Deinterlacing:-
This is a process whereby video signals coming in from the Composite or S-Video inputs are converted from interlaced scan to progressive scan (480i to 480p) and then output via Component or HDMI outputs to the TV. This improves the quality of the image, making it smoother and more acceptable for display on an HDTV.
However, keep in mind that not all receivers can perform this function well.
Video Upscaling:-
In addition to deinterlacing, another level of video processing is becoming more common in home theater receivers is Upscaling. Upscaling is a function that, after the deinterlacing process is done, upscales the number of pixels to match a specific screen resolution, such as 720p, 1080i, or 1080p.
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Room size, etc and power required:-
How much amplifier power you need,depends largely on
(a)
Speaker sensitivity:
Briefly, with the same power, a more sensitive speaker will play louder than one with less sensitivity. High sensitivity range is > 90db.
(b)
Room size:
Everything else being equal, a larger room absorbs more power than a small room. That's because the speaker sound we hear is the sum total of direct and reflected sounds, and sound pressure diminishes with distance. Hence, to overcome the increased volume of a large room, an amp needs to put out more power.
(c)
Listener distance.
This can be independent of room size. If you sit close to the speakers, even in a large room, you will be using less power than if you sit farther away.
(d)
Your average playback level:
Average listening levels (neither background nor party but, well, normal) require less power than you may think -- the average listening level requires somewhere around 10 watts in a standard 20'L x 14'W x 9'H room.
5)
Try at home
If the dealer let's you put down a deposit and try them at home,B'coz, the acoustic space in a showrom is different from your home.
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6)
Take your time,there is no hurry
Audition with your own material (CD's, DVD's etc). Listen to the same songs, and movies over, and over again with the different recievers and your own set of speakers(But ensure whether your amplifier support the impdance of your speakers in ohms or not,set accordingly the setting on the amplifier to required 4ohm/6ohm/8ohm). Take your time, and have fun auditioning.
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Get involved with member get-togethers
Another great way is to get involved with member get-togethers.
Its a great way to
1. Meet new people.
2. Learn.
3. Audition various combination of recievers and speakers
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Buy from an authorised dealer only
If you want ultimate peace of mind buy only from an authorised dealer with bill and warranty.Ask where they have a service center and get all details.
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Look for web/internet resources
You can Search/Google for interesting articles and reviews on recievers, both general and technical.You can also get tentative/exact price's also like here in our very own and one of the greatest site "HIFIVISION.COM".
I hope the missing points in the above write-up will be covered by my fellow members/experts
Thanks
Regards
