Audiocalibration and roomcorrection

When you've your new AV-amplifier into your living room / home theater the job of setting it up starts so you can get the best possible surround sound from your favorite movies. Here are the big differences in functionality between the different products.

Various speakers and different rooms means you have to adjust several parameters to get the best possible sound. This is the level of each individual speaker, crossover frequency, delay of sound to each speaker and the most advanced is the frequency of each speaker.

Earlier, it was common that AV-amplifiers had the option to send white noise and you had to use your own ears or a soundmeeeter to adjust the speaker level while measured distance to the different speakers to adjust the time delays. This was usually an inaccurate calibration of the level and delay. Fortunately, most amplifiers now have automatic calibration and room correction.

Automatic calibration and room correction
Home Amplifiers / processors with automatic calibration and room correction makes it easier for the user to get optimal sound. There are a number of varieties, but mainly composed systems that connect a microphone to the receiver / amplifier placed in one or more listening positions.

The first amplifier / processor does by such automatic room correction / calibration is to determine which type of setup you have (5.0, 7.1, etc.) and then checks the typical about some of the cables are connected. Thereafter bass response assessed from the speakers along with level so that a size and crossover frequency set for the different speakers. The picture below shows how a Yamaha amplifier has measured the layout and set the crossover frequency on the different channels.

There are now more and more common that in addition has room correction that makes adjustments on the sound based rendering and how the perceived sound in the room is. The simplest romkorreksjonsystemene measures only frequency hallway to the room / speakers and based on the perceived frequency curve and then try to correct the frequency curve. It varies the number of frequency bands may be used to compensate for an error frequency curve, but this is typically in the range of 5-9 bands. The most advanced features parametric Equlizer means that the bands are not clearly defined, but where the frequency and Q (width of area) may change amplifier.

The more advanced romkorreksjonssystemene makes in addition a number of customizations for room size, reflections, standing waves and other parameters to ensure the best possible experience. Many of the advanced also supports the measurement of a number of measuring points in the room to ensure that the sound reproduction is the best of all seating positions. The picture below how it is recommended to place the microphone with Audyssey MultEQ room correction.

When room correction is performed has typical opportunity to see which properties have been adjusted. (not all) Some home theater amplifiers also allow to override room correction with manual adjustment of frequency reproduction of the different speaker channels.

Manufacturers Yamaha, Pioneer, Sony and Harman / Kardon has developed their own systems for room correction while a number of manufacturers that Onkyo, Denon, Marantz and NAD uses system developed by Audyssey. The systems are evolving each year in addition to that they have different characteristics. Therefore, they will usually also provide somewhat different results for a correction.

Although room correction for many can do wonders for the sound it is always advantageous to give the amplifier the best possible basis. This means making adjustments in the room for speaker placement and decoration, to get the best sound without romkorresjon, usually will make the sound even better with room correction.