THX just announced a new specification for home theater: THX Loudless Plus. My initial thought was, "I bet this means yet another new THX equipment specification." Well, yes, it does. The benchmark specification for all future receivers will now be THX Ultra2 Plus and THX Select2 Plus. But this is not a bad thing; this specification addresses a real need in home theater: consistent surround sound levels regardless of the listening volume.
Currently, the best way to reproduce a movie sound track is to calibrate your speakers to a certain reference volume level and make sure the volume knob is always at this position. Unfortunately, if you decrease the volume level, your ears perceive the changes in the different channels differently than the front speakers. Because the 3 front speakers (left, center, front) contain most of the sound information, they appear to become relatively more loud as compared to the surround channels; this is true for teh subwoofer as well. The result is that you lose the surround sound effect.
Even existing receivers that have a Midnight Theater mode do not fully compensate for this. They compress the dynamic range of all speakers by the same amount. In other words, the loud scenes are not as loud and the quite scenes are not as quiet, but the relative volume levels between the channels is not adjusted and the frequency curve is not adjusted, so the surround channels sound quieter than they should. THX Loudness Plus solves this by making two adjustments: 1) applying a volume gain curve to the surround and sub speaker levels, maintaining the proper balance regardless of where the volume knob is set, and 2) applying a frequency correction curve to the high and low surround frequencies to better balance with the main front speakers.
For anyone who wants to enjoy surround sound with the volume turned down (or really at any setting), this is a feature to consider during your next receiver upgrade.
For those of you keeping track of the THX certifications, here is the history:
- THX certification for home theater was launched around 1998
- THX certification became THX Ultra (high power amplifiers required) and THX Select was introduced (lower amplifier power requirements)
- THX Ultra2 and THX Select2 replace the previous Ultra/Select in 2005, adding more surround modes and better 7.1 support
- THX Ultra2 Plus and THX Select2 Plus replace the previous Ultra2/Select2 and add loudness compensation
Here are some quotes from the THX website giving more detail:
THX Multi-channel Spectral Balancing: adjusts frequency response to counter the perceptual loss of low and high frequency sound in all channels. Begins with a flat response at Reference Level, and continually adjusts the response as the user selects lower listening levels. The equalization is applied to all channels in a multi-channel listening environment.
THX Dynamic Ambience Preservation: Surround channel processing preserves the spatial detail that is lost when listening below Reference Level. It automatically shapes the output on surround channels to maintain the perceived balance in the original mix.
what are the pros and cons to owning a THX reciever? What is a good reciever that would be comparible to a THX system?
The only con of a THX-certified component is the general higher price vs. non-certified. Denon and Yamaha receivers are generally great brands for the price.
We just upgraded to lucasfilm THX SELECT2 PLUS and we love it and especely for blu-ray content the problem with blu-ray and thx is that blu-ray has a very harsh signal strangth problem so on some movies we found that if you play at commercial theater refrance it was between 105-120db that is way too load so ilike this new certification it was a good idea because now you can play back any content rather its movies music games at any volume level
Another thing that the new THX SELECT2 PLUS certification offers is THX PLL2 MUSIC MODE THX SELECT2 GAME MODE THX SELECT2 MUSIC MODE! with DDPll2x thx music mode you can now play back music exacly the way the recordist intended and whats nice about thx music mode is you can use 2 channal recordings with it so not all your music has to be recorded in 5.1 to make this new prossesing mode work! the way it works is it takes the audio and expands it to 5.1-7.1 playback the same thing for THX SELECT2 GAME MODE it plays back gameing sound tracks which most are recorded in 2 channal stero in 7.1 channal thats cool! We spent 30,000 on this new certification thats on THX SELECT certified speakers and recever commercial ERK-54 seires midatlantic rack adioquest cinemaquest cabeling and acousticly made the room corect i love it what people need to realize is that THX is a CERTIFICATION not a surround sound
Another thing to consider if you want to do thx certification is the power and performance of your system i would recomend that you use tripplite UBS systems with the power managment issue tripplite has automtic voltage regulation and battery backup system this will insure you have the right power levels and porformance for your system and if the power goes out the UBS will back your system up long enough to power down corectly you also need them because thx requires alot of power anyway to even begin to hit commercial theater refrance level!!!!
On december 8th I was talking about thx and certification and so forth but its not just the equpment its the display to i would recomend for a projector the mitsubushi HC3800 this new projector has a 4000:1 contrast ratio and is capable of doing a format called 2:35:1 cinemascope thats with a anamorphic lens and screen the reason i say this is because most movies and i mean 80% are all recorded in 2:35:1 cinemascope so if you have about $10,000 than its a good idea if not than onkyo and integra recevers have a new zoom mode called WIDEZOOM which takes 2:35:1 content and zooms it to fit a 1:85:1 screen without artifacs or distortion of the picture so if you run into movies that are recorded in 2:35:1 which are the black bars on top and bottom of the screen and are anoying than the wide zoom mode is a good thing to have. Another thing about the HC3800 is it is a native 1080p projector and also it has the latest advanced DLP chips and prosessers in it and it has a razor sharp picture and its only $2200.00 which is cheap the cheapst cinemascope home theater projector before this one came out was the HC6800 which retalled for about $4000.00 so this was a good move by mitsubushi.