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Contents :

Historic

Prologue

All has begun in 1998, when I was reading videos games books about advanced decoding (Dolby Pro-Logic) which going further than the simple stereo ! Indeed, in addition to the stereo speakers, two back speakers and one central speaker appeared with the Dolby Pro-Logic decoder. In fact, the surrounds (back speakers) were solicited on precise moment but they were only in mono to simulate a sound which were coming from the back of the listener. Frightening ! On the book, the article dealt with games like Formula 1 97 and Wipeout 2097 video games (which the surround sound coding was pretty strange) on Playstation using this process.

At this time, I owned a simple cathodic TV, Thomson mono (not very compatible with 60 Hz/NTSC).

Christmas 1998, I have acquired a Sony STR-DE225 amp (4x40W DIN under 4 Ohms), a powerful monster ;-) with speakers that were found on the granary, most of it without brand (oldies)... The worst of them was the surrounds with 10W musical under 4Ω (errr). The center speaker was like back speaker for car audio use.

Then the subwoofer came during the year 1999 and it was a great ass kick (it clearly shows the lack of bass of the other speakers).

My first home theater Pro-Logic in complete -1999- !


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Changes

On 2001, I was able to buy some equipments to upgrade my installation. First of all the TV, replaced by a Grandin 55 cm in June 2001. The purchase of Infinity Reference MKII pack during 2001 put my oldies to what it were destined (oubliettes). And I didn't have pulled up the volume pot of my Sony with these Infinity speakers, because I didn't want to deteriorate them, considering the power of my Sony...

Logically, the amp was next. And then, the amplificator Yamaha rxv-630rds titan version drived all that at the beginning of 2003 with, in addition, a Pioneer DV454S dvd player to replace my PS2, which have forgotten how to play dvds...

Changes resume -2003- :


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Optimizations

To do with great care (I had the impression of an imbalance on the surround), I took a sonometer.

After few reading on a funny topic, I wanted to buy an hifi amp ! The Sonic Impact T-Amp (review). And there was a big difference with the Yamaha amp...!

To go further, the Super T-Amp was next, and I think it's very good for the price. Indeed, I heard a Rega Mira 3 with a Planet cd player (I guess) driving Comet Triangle, I didn't like it, the sound was too manipulated in my opinion (and the T-Amp had more punch !).

It's the junction of home theater and hifi, considering that I had the Super T-Amp driving the fronts and was useful for hifi listenings. A DIY (Do It Yourself) project replaced the Super T-Amp (see Hifi section).

February 2007, my TV died, then replaced with a LCD TV Sony KDL-32V2500.

Today's settings :

September 2009, PS3 is there for me !

October 2009, my subwoofer's out. Replaced by a Velodyne CHT10-Q, wooo, it rocks !

May 2010, AMP5 (DIY) is finished and then replaced the Super T-Amp for the front speakers.

August 2012, I buy the Lexicon MC-8 preamp (upgraded to the last firmware).

April 2014, PS4 is at home, replacing the old PS3 (no more connected).

May 2015, the AMP10 (DIY) is finished, replacing the AMP5 for front speakers. The AMP5 is still used but only for the center and surround right speakers. The Super T-AMP is only here for the surround left speaker. The Yamaha rdv-630rds is not connected anymore.


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Today

For now, here is the list :


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Setup

How to setup HT ?

Setups are differents considering the room volume, speakers specifications and amplificator specifications. Some have a micro for the calibration to simplify the task. The first thing to do is to place correctly speakers : symetric (so that the soundstage is centered), distance with the walls to avoid heavy basses with poor quality (see Dolby's website for further informations for the recommandations).

Then if you don't own micro with the amp, you will be steady for the speakers level. It is a rarety thing to own front, center and surround speakers that have the same sensitivy. You should use the Test Tone of your amp for that. Don't hesitate to pull up the sound level with this test in order to hear the sound level differences of each speakers. It is possible to have different values even with identical speakers (because of the room).

If you own a sonometer, it will be more precise. There are several ways to use it, but the one I'm using is as follow : run the test tone on your amp and set up the sonometer on the C position (slow) and between 70 and 80dB position (depending on the values available). Increase the amp volume until the sonometer stabilize on the value chosen between 70 and 80dB. Do it for each speakers, by increasing ou decreasing values on the amp so that the sonometer shows the same value everywhere (if you have followed until here, the one between 70 and 80dB). Voila it's set up ! Nevertheless, don't use the sonometer to set up your subwoofer, unless you own a big quality sonometer !

Once this done (the easier part), speakers options on your amp is the next.

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Basses

Actually, you can declare your speakers as small or large. This can change the way the amp will send basses. The perfection should be to have identical speakers in large, capable to reproduce deep basses. Those ones are generally very expensive.

Large means that all sound informations to this speaker will be sent integrally. In small, basses too deep, below the frequency crossover defined in the amp, will be sent to the subwoofer or if it don't exists, to speaker in large. You should be aware and you should know if your speakers are good enough to reproduce deep basses to avoid to loose sound informations (typically lack of basses).

To make it simple, if you have high speakers and a correct subwoofer and not high-end quality speakers, set them as small, otherwise as large. If you have only speakers in small, take a good quality subwoofer otherwise you will have a huge lack of basses (i.e an explosion looks like a firecracker :-)) or an overcharged subwoofer !

The subwoofer is the hard part to set up, because it must be transparent and unlocated. We should not know that it's running !

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The subwoofer

We are on the hard part because basses will be either too presents and unpleasant (overload of the subwoofer at worse), or too discretes and in this case we will loose in immersion, or simply sound informations on the basses.

On the first hand, get a test cd or a wav track that you will burn on a audio cd playing on your audio player. If possible, get a test with basses going from 250Hz to 30Hz for example, in order to derterminate if the transition between basses from speakers in small and the subwoofer is transparent. In the same way, it demonstrate if there are some holes or pics in basses restitution from the subwoofer.

The subwoofer level setting allow you not to overload the sub or in contrary to level up its level so that it will be the same level as speakers it come along. The subwoofer phase (between 0 and 180) allow you to modify the basses diffusion in the room and better setting its transparency with other speakers (help too for holes or pics). Don't forget neither the subwoofer placement in the room, it can change things too.
The test bass from THX Optimizer (included in some DVD) is usefull because it goes from 200Hz to 20Hz. The final rendering should be transparent and with the same level all the time even with subwoofer crossover. If you have a recent amp, it can allow you to set up severals crossovers for basses, use it compared with other speakers. Don't forget that the less the subwoofer has low frequencies to reproduce, better it can restitute the frequencies it must reproduce. Typically, a subwoofer that is setting up to give frequencies between 200Hz and 20Hz must be a very good quality subwoofer ! Moreover, the sub don't have to reproduce basses all the time of all movies, some movies are quiet and if the sub is discrete, it's because the engineering sound want it. If your tests with the bass cd are good, keep the settings. All DVDs are not good mixed and some will make you doubt about your settings (personally, the Terminator 2 movie in french DD 5.1 version had too much low frequencies, poor mixing).

Voila ! You can now do the unending tests with low frequencies from subwoofer in hometheater !

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