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Setting up that home thread system - calibration, auto-eq, Audyssey etc

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Old 07-01-2010, 12:21 PM   #16
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Why 7.1?


All About Immersion
What are the benefits of adding the two extra rear surround channels to achieve 7.1, and what circumstances would justify the upgrade? The benefits are greater surround envelopment, depth, and “immersion” in the surround effects field, both for movie effects and for musical ambience, plus much improved surround coverage for various listeners seated throughout the room.

One requirement for 7.1-channel surround is sufficient space behind your couch and listening area—at least 5 feet or more. If your couch is jammed up against the rear wall or you have a comparatively small room of less than about 2,100 cu. ft. (length x width x height), the addition of two rear surround speakers will not likely add significant improvements in envelopment, especially if you are already using Axiom’s QS8 or QS4 “multi-polar” surround speakers. However, if you have the space behind the listening area to play with, and/or your room is medium to large sized (especially so-called great rooms and family rooms), four surround speakers will deliver noticeably improved surround envelopment and coverage for all viewers in different seating locations.

While the great bulk of movie soundtracks (including all SACD and DVD-Audio music discs) are mixed in 5.1 channels, there are increasing numbers of movies (the Harry Potter movies and other movie “spectaculars”) mixed in 6.1 and 7.1 channels, including a surprising number of games. But the real justification for upgrading to 7.1 is the sophistication of smart decoding algorithms from Dolby Labs, dts, and Logic7 (the latter exclusive to Harman-owned companies).

Among its many virtues, Dolby Pro Logic IIx (DPLIIx) as well as earlier versions has the ability to extract or interpolate extra surround data from a standard 5.1-channel mix or even from stereo sources, and re-direct that information to both side and rear surround channels, all of which will increase the sense of depth and precision of the surround experience. (Don’t confuse this process with the “seven-channel stereo” option offered on many AV surround receivers. While pleasant, it only parcels out two-channel stereo among all the speakers in a system.)

Reasons to Believe
No matter how you look at it, there are persuasive reasons to consider upgrading to 7.1 channels with its four surround speakers. Incidentally, there is nothing fake or phony about electronically extracting surround data from existing 5.1 or even 2-channel stereo soundtracks. Just two microphones in a conventional stereo purist recording will pick up all kinds of out-of-phase information, which commonly characterizes ambient surround data, so re-directing those sounds to the sides and rear is really just placing them where they would occur in a dedicated elaborate multi-microphone recording array.
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Old 07-01-2010, 12:22 PM   #17
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Dipole vs bipole vs direct radiating


Direct Radiating Speakers
A direct radiating speaker outputs sound directly into the room towards the listeners. Surround sound effects in movies, music and games are most noticeable with direct speakers. In general, most people prefer direct speakers if they listen mostly to multichannel music. Direct speakers are placed at the sides or rear of the listening room behind the listeners.

Bipole Speakers
Bipole surround speakers have two or more speakers that output sound from both sides of the cabinet. If used as side surround speakers, the sound is output both towards the front and rear of the room. If used as rear surround speakers, they output sound in both directions along the rear wall. The dual speakers used in a bipole speaker are ‘in phase’, meaning that both speakers output sound simultaneously. Bipole speakers create a diffuse surround effect so the location of the speaker cannot be pinpointed. In general, bipole speakers are a good choice for movies and music and are usually placed on the side walls.

Dipole Speakers
Like a bipole speaker, a dipole speaker outputs sound from both sides of the cabinet. The difference is dipole speakers are ‘out of phase’, which means that one speaker is outputting sound while the other is not, and vice-versa. The purpose is to create a very diffuse and enveloping surround sound effect. Dipole surround speakers are usually preferred by movie enthusiasts and are also placed on the side walls.

How to Choose Surround Sound Speakers
In addition to considering the guidelines above, some speaker manufacturers such as Monitor Audio and Polk Audio have made your decision a little easier by including a switch that allows you to select bipole or dipole output on the surround speakers. Denon even provides dual surround speaker switching on some of their AV receivers so you can use two pairs of surround speakers, direct and bipole/dipole and switch between them for movies or music.

Courtesy of Polk Audio

In a Dipolar speaker, the two sets of speakers are out-of-phase with each other, while the drivers are one side are pushing, the opposite side is pulling. The result is that there is a "null" or a dead zone of sound in the area along the 90 degree axis of the speaker (see illustration below). Why is that good? When properly set up, a pair of dipole speakers used as surround speakers will provide a very open, enveloping rear effects soundstage without allowing you to pinpoint the location of the speakers themselves. That's a good thing. But for all this to work properly, the speakers need to be positioned "in-line" with the listening position as shown on the illustration below. If you are sitting out of the null area, the effect is ruined. What if you can't or don't want to place your surround speakers and listening position as required? That's where bipoles come in handy.

In a Bipolar speaker, the two sets of drivers are in-phase with one another - both sides push air at the same time. The result is greater sound output where the dipolar speaker's null would be. Theoretically, a bipolar speaker approaches a 360° soundfield - it squirts sound all around the room. That's a good thing if you need to position your surround speakers behind your listening position or anywhere outside of the null area. Some people prefer the greater localization of bipolar speakers when used in digital discrete (Dolby Digital 5.1, DTS) systems.

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Old 07-01-2010, 12:23 PM   #18
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Fig 1. Standard Dolby Digital 5.1 / DPL II Setup

Fig 2. Dolby Digital EX 6.1 and Dolby Pro LogicIIx 7.1 channel Setup

Fig 3. Suggested Corner Arrangement of Dolby Digital 5.1 Channel Setup

A good article on speaker placement:


Unlike the front speakers, the job of the surrounds in a home theater is to create a cloud of non-localized sound that envelops the viewer. It is this diffused rear sound field, which actually makes you feel like you are in the middle of the movie action.

Though preferred surround speaker positioning is very much dependent on personal tastes, yet there are a few home theater speaker placement issues worth taking note of:

Surround speakers should ideally be placed alongside and slightly to the rear of your main seating position. This will help mimic the sound field as originally recorded in dubbing theaters when mixing movie soundtracks.

Sidewall placement is preferred; this helps create a seamless, enveloping soundstage over the whole listening area.

If sidewall placement is not possible, try to make use of appropriate speaker stands.

Position the speakers two to three feet above your seated ear level; this helps create the most diffused enveloping sound field in the listening area.

In the case of 6.1 and 7.1 home theater surround sound systems, distribute the surround speakers such that these are preferably wall mounted on the sidewalls and the back wall. This kind of home theater speaker placement would further enhance the enveloping effect.
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Old 07-01-2010, 12:24 PM   #19
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Suggested positions


This are only suggestions by Dolby, which you can disregard, but they are tried and test...

This is already posted in the sticky:

Some images to help you get speaker placement right:


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Old 08-01-2010, 02:47 AM   #20
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Simple AV amp setup tips

- you may wish to have a mirror behind the amp stuck to the wall or the shelf so you know what inputs are there

- label each cable

- give yourself not only enough room for the cable connected, but also for you to put your hand there and remove it in future

- I suggest at least 4 inches of space around the amp - more if you own one of the Onkyos or other designs where there is a fan to blow the heat away

- the amp should ideally sit on the strongest shelf and be on the top shelf too

- cover unused inputs with the silicon or plastic cap protectors to prevent oxidisation

- I stick a simple light near the back of my amp - so I can see what I am doing to adjust the cables and also remove them more easily
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Old 08-01-2010, 02:48 AM   #21
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Re: Marrying your HT and stereo system

Courtesy of Siriusly Cold:


1: Receiver + Stereo integrated Amp

stereo integrated amps are a dime a dozen (well almost, and even older ones are quite good sounding)

two pre-amp stages will mess with the signal upredictably
controlling volume between CD and DVD listening will be a challenge
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Old 08-01-2010, 02:50 AM   #22
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Room treatment

Room treatment can make a bigger impact than changing to a better speaker and even speaker placement will help. The best part of this is it is lower cost than buying new equipment, so maximise what you have first before buying more things.

This is a useful article:




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Old 08-01-2010, 02:53 AM   #23
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Info on Banana plugs






How to remove plugs from your amp:


Last edited by petetherock; 08-01-2010 at 02:56 AM..
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Old 09-02-2010, 03:12 PM   #24
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Configuring Speakers


Optimizing your sound, one step at a time.

Getting all the pieces for that new system into your room is just the first step to home theater bliss. You’ll need to set up the A/V receiver’s inputs, position the speakers, and configure the AVR’s speaker adjustments for balanced sound before you get to movie time. I’ll frequently refer to your AVR, but the steps will be identical for a separates system with a surround processor and power amp.

Configuring the system isn’t as complicated as many owner’s manuals make it seem. Most AVRs guide you through the operation through their onscreen setup menus by breaking the process down into organized, manageable steps. The process is basically the same for all systems: connect and set up the sources, connect and position the speakers, and set the A/V receiver’s speaker configuration controls. A growing number of A/V receivers also add automated setup and sophisticated room equalization to their list of features.
Source Setup
In some A/V receivers, source setup is intuitive. You connect your DVD player to the DVD input, your TV to the TV input, your satellite box to the SAT input, and so on. However, some receivers may not label their inputs as DVD, SAT, TV, AUX, etc., but rather AUX 1, AUX 2, Digital 1, Digital 2, Component 1, Component 2, HDMI, etc. These receivers will ask you to designate which source you have connected to each of these inputs. For example, you might connect your satellite receiver to Component 1 and your Blu-ray player to HDMI. In most cases, the receiver will then let you rename these inputs so that its front-panel window will read Blu-ray and SAT instead of HDMI and Component 1.
For analog video sources (composite, S-video, and component), you’ll not only find video jacks but also a choice of audio inputs, either analog or digital (optical or coaxial). Make sure that you assign the audio and video to the same input selection in the menu, or you may find that when you select the input, you get audio but no video—or vice versa.
If you want to listen to the new high-resolution lossless audio soundtracks that are found on most Blu-ray Discs—Dolby TrueHD, DTS-HD Master Audio, and multichannel PCM—you must use either multichannel analog connections from the player to the receiver (six separate analog leads) or an HDMI link. The old optical and coaxial digital inputs can only carry two-channel (stereo) PCM digital or multichannel as old school (lossy compressed) Dolby Digital and DTS.
Some Blu-ray players offer multichannel analog audio outputs. But HDMI is the way to go if you want the best high-resolution audio and video, not to mention the easiest connection. HDMI can carry both audio and video from the source to the receiver on a single lead. You simply connect an HDMI cable between each source and the receiver, assign the sources to the connected input when you set up the receiver (as in the above example, Blu-ray to HDMI), and you’re good to go. But with older sources, such as an old cable box that lacks an HDMI output, you’ll have to use separate audio and video connections. Some audiophiles argue that a two-channel CD coaxial (not optical) digital link sounds better than HDMI, but that’s a controversial discussion for another time.
Speaker Setup
I’ll assume that you’ve properly positioned your speakers. (See Darryl Wilkinson’s “Speakers: Where Do I Put Them?” feature on page 30.) That means the left and right front speakers flank the screen symmetrically and are far enough apart to produce good separation but close enough together that there’s a center image and no hole in the middle when you listen to two-channel stereo. The surrounds will be positioned behind the listener. The recommended surround location (for a 5.1-channel setup) is generally 110 degrees from the center speaker (to the left and right and just slightly behind the main listening area). However, in some rooms, you may need to position them further to the rear.
You should locate the subwoofer in the position that produces the deepest, tightest, most well-defined bass possible. If you haven’t determined this location yet—and most newbies have not—the process can involve a lot of trial and error. For your first try, choose a promising location; a common recommendation is between the center and right front speaker. If this doesn’t work as well as you’d like, move the sub around the room (with appropriate readjustment of the level, distance, and other setup controls in your AVR each time) until you find the best spot. Selecting the optimum location for the subwoofer is an art. Books have been written about it (well, many thousands of words at least). Many of you will be perfectly happy with the first location you try. The location is usually influenced by practical room considerations, not to mention the demands of your in-house interior decorator! Others will fuss for weeks for that last ounce of bass magic. That’s up to you.
Speaker Configuration
Once the speakers are in position, you’ll need to set up the system to account for a number of factors, including the distance of each speaker from the listener, how much bass you want each speaker to carry, how you want to redirect the bass, and what each channel’s playback level is.
For this discussion, we assume that you’ll perform these adjustments in your AVR. Many disc players, both DVD and Blu-ray, also offer setup for these parameters. Most often, these only affect a player’s analog audio outputs. If you must use a multichannel analog connection from player to receiver, configuring the player may be the only way to dial in the settings for that source. Most receivers’ multichannel analog inputs offer little more than level adjustments. But for all other inputs, the receiver’s setup is by far the best way to go. In fact, most of you are unlikely to use the multichannel analog inputs at all.
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Old 09-02-2010, 03:13 PM   #25
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Most subwoofers have their own internal crossover networks to roll off the bass to the sub above a selected frequency. However, since you’ll use the receiver’s setup menus for this, you should set the subwoofer to bypass its own crossover. Some subs might also have a separate, unfiltered input for this purpose. If the sub doesn’t let you bypass its own crossover network, you should set it to the highest possible frequency so that it doesn’t interfere with the receiver’s crossover.

Many receivers use the designations “large” and “small” for each speaker in their setup menus. Selecting large allows the speaker to operate full range. Small redirects the speaker’s bass below the crossover frequency. If you have a subwoofer, the bass for the speakers designated as small is redirected to the subwoofer. If not, it’s redirected to the speakers that you’ve designated as large—most often these are the left and right front speakers. Some receivers complicate this by offering the option to redirect bass to both the subwoofer and the large speakers. We don’t recommend this option, since it often leads to muddled, overblown bass.
Most (but not all) A/V receivers offer a range of crossover frequencies. When in doubt, 80 hertz—the frequency that THX often uses—is always a good place to start. It works well with most speakers. In fact, just because some of your speakers are full range, with very good bass response, doesn’t necessarily mean that you must designate them as large, or even that this will be the best choice if you have a subwoofer. You can select small for those bass-capable speakers as well and let the subwoofer handle all the deep bass—a setup that many of us prefer. Even speakers that offer more than sufficient bass for music can be overloaded with the bass from action sound- tracks played back at high levels.
Distance, Levels, and Equalization
The distance adjustments simply tell the receiver how far away the main seating position is from each speaker. This ensures that the sound from each speaker arrives at the listening position at the same time. Measure the distance from your favorite seat to each speaker and enter these values into the menu.
All AVRs provide a test signal that circulates from channel to channel, along with controls to match the levels of each channel. You can either level-match by ear or with a sound pressure level (SPL) meter. Setup by ear is a quick and dirty option that can work reasonably well, but an SPL meter is far more accurate. There are a number of sources for these devices. RadioShack offers both analog and digital SPL meters for under $50. We generally recommend the analog version—it’s only slightly cheaper but easier to use. Hint: Set the meter’s response to slow operation and C-weighting.
Most A/V receivers now offer some form of automated, onboard setup and equalization, together with a microphone. The effectiveness of this feature varies from receiver to receiver, particularly in the low frequencies where room compensation is most needed. Some receivers use their own proprietary algorithms, while others use third-party technologies. Of the latter, the best known and most widely used is Audyssey MultEQ.
There’s no guarantee that you’ll like the results of auto equalization, but if your receiver has this feature, you’ll at least want to try it out. The actual setup will vary from receiver to receiver, but the procedure is (usually) clearly described in the owner’s manual and easily defeatable if you don’t care for the result.
Many receivers also offer manual equalization controls. But unless you know what you’re doing and have the right test tools, setting equalization by ear, particularly in a multichannel system, is a recipe for sonic garbage. The auto system will almost always do a better job.
Automatic Audio Calibration
Some form of automatic audio calibration is now almost universal in A/V receivers. All you need to do is set up the included microphone at the main listening seat, engage the auto setup feature, and go make yourself a sandwich. The receiver generates a set of test tones that determine all of the important speaker calibration settings: size, delays, levels, and, sometimes equalization as well. In receivers that combine auto equalization with auto calibration, you can generally defeat the equalization after setup, if you prefer, while leaving the other calibration settings intact. The only thing left for you to do is make the popcorn.
Well, almost the only thing. These automatic systems often make odd choices for the size of the individual speakers in the system. An auto system might classify your L/R speakers, capable of flat response only down to perhaps 60 Hz, as large. But it has no way to know that these speakers will overload easily with a high-level, 30-Hz signal. It might do the same with the center channel or the surrounds. While the auto setup function can be a blessing, it’s no miracle. A little intelligent oversight is needed. If you want to drive all of your main speakers as small, just go into the menus after the auto calibration is finished and change the settings as you see fit. The same applies if you want the surround levels a little higher or if you want the subwoofer level a little lower. All of the receivers we know of let you adjust the individual channel levels even after an automated calibration.
There’s More?
There’s a wide range of additional features on many receivers. Just a few of these are the ability to choose different crossover frequencies for each channel, various forms of dynamic volume and dynamic equalization, cross-converting all video sources to a single HDMI or component output, built-in video processing, different setups for multichannel and two-channel operation, different ways of treating the LFE channel (the .1 channel in a 5.1- or 7.1-channel system), and multiple zones of operation. These features vary significantly from one design to another, but they are rarely crucial to the basic setup. They sometimes clutter up the setup menus, but you can usually ignore them until you become familiar with your A/V receiver’s basic operation. When you’re ready, feel free to experiment with one or more of these advanced features, knowing that you can always defeat them later and go back to your first, trusted setup.
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Old 22-03-2010, 04:47 PM   #26
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Satellite Speakers

So firstly, what are Satellite Speakers ?

Well they are small form factor speakers which don't go down low.
Usually they will stop producing meaningful sound before 100Hz.
They are small, usually aesthetically pleasing and light.
They will need bass reinforcement from a subwoofer.
For many who live in small apartments or have to work in the interior decor and wife factor, they are the facto choice.

Sats (as they will be shortened to)

- are not value for money (VFM)
- they usually have lousy mids especially the cheaper examples
- will need a subwoofer to fill in, some crossover at 100 Hz but if they can reach 80Hz, thats more ideal as the bass unit will be less localisable
- they can be mounted on walls or stands - I suggest hanging them first before permanently fixing them, so you can figure out the ideal spot
- they can suck up quite a bit of power, many of them being inefficicent so a good amp with at least 70-100 real watts per channel is useful
- not all of them are light so make sure your mounts can take them
- they are better for HT than music

So with so many issues, why buy them??

I ask that of our bros often when they want the cutesy thing. Simple reason - WAF -- wife acceptance factor ---- "I need to blend in with my decor" / "my wife / partner doesn't want the speakers to dominate the room" / "my kids might destroy the speakers"

Well then, that is a choice, and I respect that, but don't ask why they sound worse than someone else's setup for the same money and where the mid went

It is harder but still possible to integrate the sound, a bit more effort and a realistic expectation is needed.

Doing the demo:

First, do some reading, then select a few systems which fit your budget, and style requirements, after all this is the satellites (read STYLE OVER SUBSTANCE) thread.

So getting your wife or partner involved is essential. Then pop over to some shops to listen and audition with your favorite pieces.

Take note of how the room is setup, is it close to your own home in dimensions, the amount of room treatment etc. Some places have comprehensive room treatment and that will make a cheaper system sound much better than certain other showrooms.

Some popular shops have sales staff which have become less helpful than they should be, and their setups are quite haphazard, so take your business and spread the love around.

TEG's B/W M series is well setup, and the staff are friendly if the price suits you.

Seng Heng has a decent MS based setup which shows off what a lower end system can do, but note he uses a more expensive sub in that demo.

GP Audio's KEF is well setup and Kelvin is a friend chap.

Precision Audio's Edward is er, famous... but actually catch him on a nice day WITHOUT the other senior guy who just takes up space and looks down on newbies and try out the Radius system, which IMO is decent and the large centre with the sub have got it right.

Also if your WAF allows, consider the smaller bookshelf speakers as mentioned earlier, as they can give you better sound per pound.

After trying out a few systems, ask permision from members here, who have similar setups, and ask them to let you hear the speakers in a domestic setting, which is the most realistic. Most members here are friendly, bar a few rude chaps or unpleasant characters, and they will welcome you into their homes.

A note of warning: if you tell someone you want to come, jolly well turn up or inform earlier. I have a list of banned chaps who have stood me up before and I have passed them on to my pals. You will never be invited again.

Finally sit down with your partner, draw a realistic floor plan and together with the informatino posted on the forum on speaker placement, calibration and setting up, go out and buy. After NEVER look again at prices, or you will continue to be poisoned by the stuff posted.

Small bookself speakers versus true satellites

When you consider a system based on aesthetics, there will be compromises, either in terms of paying much more for the same kind of sound, or that you don't get that kind of effect which a proper bookshelf or floorstander speaker can provide.
But there are some ways around this. The small form factor is sought after to fit the decor in the home due to WAF reasons or is chosen simply due to space constraints. But if using a small bookshelf speaker is a possibility, then do consider it. For example the Wharf 9.0 is an outgoing speaker which is small and not too ugly and coupled with a decent subwoofer will be pretty decent. Other brands with small bookshelf sized speakers include Mission, Monitor Audio, PSB, Morduant Short, Energy etc etc.

The key is to try and accept a proper sized centre and add a good subwoofer, which I have mentioned many times are the lynchpin of HT. No mini centre can reproduce a male BBC radio presenter's voice adequately. You don't need to stick to the same brand sub, for example, small footprint subs like the Earthquake Minime and the Velodyne SPL series or the Paradigm Cubes are small yet powerful subs which will created much of what is needed in a small room. These cost < 1.5k mostly.

Finally a word of advice to those in the planning stage:
if you only intend to buy in 6 months, then whatever prices and questions on models you ask now are purely speculative and the whole HT scene will change, unless you intend to buy now then store it. And be realistic with your budget, either stick to the 2-2.5k amount and understand that it is wholly inadequate and you will compromise on sound or increase the amount. Checking out things from a vast price range discourages others from responding since it seems you are not really serious or do not know what you want.


In this modern age of auto-calibration, we leave much to the amp.

However since satellites cannot go low, and often stop being effectively at higher frequencies, we have to do some homework ourselves (actuall we should anyway, auto-whatever not withstanding).

Most small form satellites crossover - i.e. the frequency at which they need help from the subwoofer, at higher frequencies than the THX bog standard of 80Hz. Sometimes this is 100, 120 or even 200Hz. Individual speakers may also have their own crossover frequencies, eg the centre speaker may be larger and crossover at a lower frequency than the rest - 100 vs 120 for example.

If you have a modern AV amp, it may be able to take care of all this, and comes with built in individual crossover frequency settings. Even this may be insufficent if your satellite speaker is of the miniscule nature.

Then you need to make sure your subwoofer has a crossover frequency or high frequency rolloff dial. This is the frequency adjustment in which the sub hands over the sound to the tiny satellites. Turn it up to get a seamless marriage of sound between the sub and the sats.

You will need a SPL meter, and if you think it is too hard, pay for someone to do it for you.

NOTE: the higher the crossover freq, the more likely the location of the sub will be localised - i.e. you know where the bass is coming from, instead of being omni-directional.

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Old 07-04-2010, 06:46 PM   #27
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After calibrating can you change the settings?

This is asked quite often, and yes you can.
If you tweak the distance, the crossover and size of speaker settings, Audyssey and EQ / Volume will work, but if you go manual with the equaliser, it won't.

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Old 05-05-2010, 09:35 AM   #28
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Home Theater Multiple Subwoofer Set-Up & Calibration Guide

Brilliant article if you wish to recreate Jason Yeo & koma's multi-sub systems:
In order to take advantage of the information in this article, you will need the following items:
SPL meter
RTA or FFT analyzer with at least 1/12th octave resolution
Patience and perseverance
This is NOT for those looking for a one button solution and have no patience in setting up or don't wish to spend time.
4 subs:

2 subs:

THX Subwoofer Calibration Recommendations
When discussing this article with THX, they suggested the following guidelines to follow for proper subwoofer placement and setup in which apply most closely to rectangular shaped rooms. Odd shaped rooms will have to experiment a bit more to find the best positions.
There are a few variations for subwoofer placement, depending on how many subwoofers you have in your room. Small rooms generally mess up the bass with "room modes." The five things that you can do to control it are:
Choose a room with dimensions so that the modal frequencies do not overlap
Place the seats where you are not at a modal peak or dip
Place the subs so they help control the amplitude of the modes
Use low frequency absorbers to knock off the peaks of the bass
Equalize (as a last step when everything else has been optimized)
In general for rectangular rooms; if you have four subs, THX recommends starting with one in each corner, if you have two, put them in opposite mid-wall positions, if you have one place it in one of the corners along the front wall. Next listen to the seat to seat variation and move the subs along the walls until you achieve the smoothest bass coverage. Being able to move a separate subwoofer around the room to find the best location many times outweighs the benefits of a "built-in" sub. Follow subwoofer positioning recommendations, perform the proper measurements and always trust your ears. When determining the best subwoofer placement, you should always move your subs around the room to determine how the room affects bass quality.
[size=10pt]Summary of Main Points
For those that want the bottom line on multi-subwoofer setup and calibration, here it is.
Choose your subs wisely - preferably all identical subs or subs with near equal f3 (3dB rolloff) points.
Place your subs wisely - in home theater rooms, nothing is more important for achieving good bass than proper placement of your subwoofers and listening seats.
Make sure all your subs are playing the identical signal - all of your subs should be playing a mono signal that consists of summed bass from all speakers set to "Small" plus LFE info.
Setup bass management - in your A/V processor/receiver, set all speakers to small, use 80Hz crossover setting as a start, and defeat the internal LPF of all of your subwoofers.
Level match all of your subs - make sure each sub is playing at the same output level. Then match their combined level to your main speakers or center channel at your listening positions.
Vary parameters to optimize response – (ie. distance, phase, crossover setting, level, physical placement) to achieve the best measured response of your subs + main channels for your primary listening seats.
Engage auto-EQ or use the manual EQ - to optimize your response at your primary listening seats. Remember, it's usually better to apply a single equalization correction curve for all subs simultaneously. This applies for all room correction systems, not just Audyssey. If auto EQ doesn't improve the sound of your system, disable it!
Listen to the end results – listen at your primary listening seats and tweak level and crossover settings only if needed.
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Old 06-09-2010, 09:16 AM   #29
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What To Listen For When Auditioning Speakers


Some highlights:

When comparing two speakers side-by-side, doing an AB
comparison, be extremely careful to match the levels before
evaluating. A slight level difference can make one speaker
sound better, even though the difference may not be perceived
as a level difference. Some claim that you will be influenced
by a difference of less than 1/2 dB!

First and foremost, the sound should be natural. If you listen
to vocals, close your eyes and try to picture someone singing in
the same room with you. Does it sound realistic? Likewise with
instruments. You selected recordings of instruments that you
like and have heard live. Do they sound like what you remember
them sounding like live?

Your very first impression should be something like "what nice
sound". If your initial gut reaction is "gosh, what a lot of
detail", the system is likely to be heavy in the treble (often
interpreted by beginners as "more detailed") and you'll probably
find that annoying after a while. If your first reaction is
"hey, what powerful bass", then the system is probably
bass-heavy, rather than ideal. The most common mistake for
beginners is to buy a system with REALLY powerful bass, because
it sounds "impressive" at first. After a while, though, you'll
get tired of being thumped on the head by your music.

Not to say that good bass and treble aren't important. But your
first realization should be that the music is all there, and
that it comes together as good music, without one particular
part trying to dominate it. Sit back and listen to it for a
bit. You should be able to pick out the individual instruments
if you want. They shouldn't force themselves on you, and you
should also be able to hear the music as a single piece, the sum
of its parts, without feeling like each of the instruments is
trying to grab your attention away from the others.
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Old 29-11-2010, 10:04 AM   #30
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Join Date: Jan 2007
Posts: 5,868
Curtains + room treatment:

After sorting out which of the main systems you wish to buy, you may also wish to consider various elements of room treatment.

Most new homes are nice shiny classy affairs, with designs which might even make the covers of some Home Improvement magazines. However most do not have much room treatment, and it is my personal yet strong opinion that you should consider this to be as important as a new pair of speakers.

In fact I would go as far as to say, the improvements that you hope to achieve with a spanking new pair of speakers will be negated or slighted by poor or no room treatment.

Now I will be first to say, that it is not easy as the idea of foam pads or other forms of soundproofing may not go down well with the missus. But a set of curtains are a start and most home needed them anyway.

Since not everyone has the luxury of a dedicated HT room, the inevitable location will be the living room and this place serves many other functions, and it is actually the ambient noise levels which will affect your experience.

Many demos in showrooms tend to crank their systems up to deafening levels to compensate for the noise around their showrooms, this may accentuate the bass, but tends to drown out details as our ears start to shut down, or our spouses leave the demo in disgust.

So may I suggest the opposite:

Quieten the listening environment, lower your noise floor and turn down the volume. Sounds counter-intuitive? Try it ...

Then add "black - out" curtains.

I use a guy called Joseph Hong in AMK (97946060 Hong Ming Store Ptd Ltd) - 64523830 (no financial interests in this store).

A metre of this material will be about 26$ including installation.

It cuts out light and higher frequencies - note it is Not a bass absorber.

The material is easily washable and comes in many colours. You can use it for your windows, or even to partition off a section of your hall for the HT listening, or to cut down ambient light if you are using a projector.

No sense getting a fancy and expensive PJ and have all kinds of light leaking in and spoiling the experience.

Try it and see for yourselves!

I have no financial interest or other interests in any of the items / events I write about.

Last edited by petetherock; 04-12-2011 at 07:16 AM..
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