STONES SOUND STUDIO

Setting up a home theater speaker system
Using  DVD THX audio noise test 

                                                    by
                                            Russell Storey    updated   2009

Setting up a home theater speaker system using a THX test tones  ( broard band white noise) played back from the DVD player  is one of the better ways to hear not only the sound signature of each speaker tweeter midrange and bass  but also its real  SPLdb (Speaker pressure Level) level. The THX test tones are actually testing the response of the  home theater system all the way through from the DVD player via the Home theater receiver to the speaker via the speaker leads.
Any change in the channel  levels or difference the sound signature of each speaker and or phasing (reversed speaker leads) will be very easy to detect with your ears as you listen to the signal.This very simple test signal is available from any THX certified DVD movie  disk see list of movies.

The THX test for Audio is accessed via the main menu on the DVD disk.

 Access the THX Audio  Set up  in the Sub menu  of  the Pearl Harbor DVD . Then when  sitting in your  lounge chair facing the center speaker and screen run the test  tone   and the  THX noise signal    will be sent to each channel  starting at the front left speaker then rotating in a clockwise motion  through each of the 5.1  6.1 or 7.1 channels
finishing with the subwoofer. Repeat this test several times until you get  all the channels balanced in level (a good starting point on most receivers is set  the Receiver Volume to 5/10  then pre set each channel  level to +7 /10  for all  speakers to begin with)   pre set +5/10 for the Subwoofer level .

Subwoofer Amplifier Control  level Settings using THX test tone

If your receiver has a DTS subwoofer level setting menu then set this to +10 for DTS . DTS subwoofer level should be set +10db above the standard   Dolby Digital level of 0db.

Initial Subwoofer Amplifier settings .

Turn   "OFF -ON -AUTO switch to   "ON" ,   ""  Do not use Auto .

Pre Set your  subwoofer Amplifier volume control to 12oclock and the Frequency control to 11oclock  , set the phase  switch set to normal

Play the THX Audio  Set up  from the  sub menu section of the  Pearl Harbor DVD  and set the channel levels and Subwoofer level so that the Subwoofer level by ear so it  just  complements  the Front speakers  but is not too loud .

Switch the  Subwoofer amplifier phase switch between 0degs and 180degs  several times ,  subwoofer will sound similar and in sync  to the front speakers  when the phase switch  in the  correct postition  . When the Subwoofer is out of phase the    sound will be lower in level  than the fronts and  produce  Hollow sound like its coming out of a tin can . 

to be continued ............................THX certified DVD movie  disk see list of movies.