分享設定ONKYO TX-NR 5010 & SUNFIRE HRS-12過程

pac

首先恭喜各位師兄發財，影音更進一步 ，我覺得調效器材一定有他存在價值，問題是怎樣去利用及是否是自己喜歡的。可以利用它去調較再執回自己喜歡的就最開心了。多些利用安橋的Manuel equal吧！非常有用的設置

iwc

wadee 發表於 2014-2-1 14:35
在post內，講漏左，隻十仔我已加左吸音墊，現在郁都唔郁

師兄請問張吸音墊響邊度買同幾錢？thx!

chhanthony

akira11092 發表於 2014-2-1 13:00
我俾個 Tips 你, 而家玩 AV AMP 唔好再信果隻賣幾百蚊既 "測音咪" 呢隻野其實誤導左好多師兄
將各聲道音壓 ...

有無機會要上akira11092兄度學下嘢

louis001

恭喜師兄過年享受到真正既爆機樂趣

carreyjim

恭喜師兄我都好似你咁情況搞來搞去都
唔得！我有樣唔明點解一定要set75db?點解唔可以耳仔收貨！我覺得75db d聲太差比戲院就得！
(Post76 Android 手機版送出)

wadee

carreyjim 發表於 2014-2-1 20:36
恭喜師兄我都好似你咁情況搞來搞去都
唔得！我有樣唔明點解一定要set75db?點解唔可以耳 ...

在我的家居，設定75db唔得，但唔代表其他地方～

wadee

iwc 發表於 2014-2-1 17:16
師兄請問張吸音墊響邊度買同幾錢？thx!

我張吸音墊是買二手的，聽講西九龍廣場對面有，新的要六百幾，你可在76搜尋下資料～

benchowhang

恭喜師兄過年享受到真正既爆機樂趣x2

chhanthony

carreyjim 發表於 2014-2-1 20:36
恭喜師兄我都好似你咁情況搞來搞去都
唔得！我有樣唔明點解一定要set75db?點解唔可以耳 ...

一切都係由業界定出嚟嘅標準，跟標準大家都係standard，有standard先有共通語言。



http://www.av-info.eu/audio/surround02.html

Movie Theatre Sound Levels
SMPTE RP 200-2002 specifies the levels of speaker systems for cinema and for monitoring. For film each channel of the surround system (front, center, surround and LFE) should output a sound pressure level of 85 dB(C)-slow reading- at standard fader settings. The relative sound pressure level difference between channels should be within +/- 0,5dB. See below "Level Measurement".

The maximum sound pressure level that could be output of the sound system (each individual speaker) should be up to 105 dB without amplifiers overloading or clipping.

The LFE channel is set to be 10 dB higher than the master channels (see below) to achieve the same measured listening level. The subwoofer channel, measured with wide-band pink noise on a realtime analyser (RTA) should show 10dB of in-band gain compared with the main channels. See below "LFE, Subwoofer".

The surround speaker channels are set individually to -3dB compared to the master channels. See below "Surround Channels".

All movies should be presented at these above mentioned standard fader settings with a SPL of 85 dB(C). Sometimes loud trailers may need compensation downwards but normally standard level should be executed all time. BUT, often this is felt as too loud and in many theatres the standard fader level is set to 79dB(C), -6dB down from the recommendations to create a more comforting listening level.

Level Measurement


First: All channels should be checked to be in phase. To measure the acoustic output signal after finished equalization, a SPL meter (IEC 60268-17) should be used and set to 'C-weighting' and 'slow'. With wide-band pink noise -20dBFS fed to each of the three main channels separately (L, C, R), for each channel a SPL of 85 dB(C) should be measured at 'standard fader settings'. These 'standard fader settings' should represend the reference level of -20dBFS (digital full scale). This gives a 20dB headroom before clipping. The 'standard fader settings' equal the fader setting "7" on a professional Dolby Cinema processor.

The level differences between channels should be within +/- 0,5dB. A-weighting should be used when matching loudspeaker levels.

A second and more precise approach to measure the acoustic output of the loudspeaker channels is to use wide-band pink noise but instead of the SPL meter to use a 1/3 octave RTA measurement system. Feeding -20dBFS into the system (each channel individually) should produce a level of 68dB SPL in each of the 1/3 octave bands between 50Hz and 2kHz. Here together with the overall response of the X-Curve the sum of all bands would be about 83dB(C) SPL. (To get a more convinient measurement the input level could be changed temporarely to -18dBFS go get a more easy readable measurement of 70dB for each band.) This measurement procedure combines the SPL and the equalization control in one step. Peaks and Dips in the resulting curve should not extend 3dB. Dips resulting from any comb filtering should not be tried to correct by boosting the EQ! Any further boost in the EQ must be kept in consideration to not minimize the headroom of 20dB between the input signal of -20dBFS and system clipping.
If uncorreleated pink noise is used for the five channels, a measurement with all channels ON can be made and should show a level of 90dB (83dB plus 7dB of the adding channels). If a lower value is measured channels could be out of phase!

See SMPTE RP200-2002 and SMPTE 202M-1998.

LFE Channel and Subwoofers
LFE: A separate low frequency channel was introduced to reproduce special low frequency content especially for movie production. This LFE channel (Low Frequency Effects) has normally a bandwidth of 20Hz up to 120 Hz. It should not be used for the entire low frequency content of the multichannel sound presentation. The left and right channel are equipped with their own independent subwoofer systems. The LFE channel should only carry the additional low frequency enhancement information. (In contrast for home cinema systems the bass management system in included to mix the sub-frequency content of all channels into the subwoofer channel.
See: Surround-Sound.)

The LFE channel is different from any other of the five surround channels and is recorded with a level offset of 10dB (recommendation ITU-R BR.1384). Why 10dB lower? With old magnetic oxide tapes for surround movies the level for the LFE channel was brought down by 10dB to not overload the recorded LFE track, improving the low-frequency headroom on the film. The 10dB level offset was turned up again in the cinema processor to compensate for the difference. This approach was possible because the high cut filtering eliminates any hiss or higher frequency noise that would be introduced by the additional level gain.
With digital recordings and signal transmission (Dolby Digital) the bandwidth of the LFE ".5" channel is only 1/200th of the main channels sample rate. The sample rate is 240Hz for the 120Hz signal bandwidth for a 48kHz sample rate for the main channels.
For any bass management system or bass management programming in the audio DSP system for home cinema or any semi-pro system it must be kept in consideration that the incoming LFE channel signal is always 10dB lower than the sub-frequency content of the main channels.

Subwoofer Main Channels: The main channels left, center, right are normally equipped with additional subwoofers that belong to these channels and are completely independent from the LFE channel and from each other. They reproduce the individual low-frequency content of these channels. Only in home cinema or semi-pro installations these subwoofer signals are combined to one subwoofer channel via the bass-management (see below).

以下情況有啲似樓主個case。

http://chhanthony.blogspot.hk/2011/04/2011415keith_18.html

Setting 完crossover後就到sound levels，Keith向Anthony表示當做完第二次Auto Set Up後發覺要將總音量開到好大先聽得清楚。其實只要知道音量運作嘅原理就會發覺Master Volume嘅數字係無乜意思。先了解sound levels嘅用途先，呢個功能係希望將AV AMP對不同效能嘅speakers輸出嘅音壓調到一致。而THX嘅指引係將所有嘅speakers校致75dB呢個水平為之達標準。

從AV書籍所知，dolby labs嘅reference 音壓為105dB，而一般AV AMP嘅pink noise為dolby labs嘅reference值減30dB，所以得出75dB(105dB – 30dB)呢個數值。將所有speakers校至同一音壓係因為唔希望各聲道音壓不一問題，所以是否75dB呢個已經唔重要。

另一方面要知道Master Volume控制入電量，而Sound Levels係控制訊號放大，如果將Sound Levels收至好細，令訊號微弱，只係不停加大Master Volume係只會大聲。相反將訊號加得太大會有機會出現失真同拆聲。如果訊號強弱恰當，係動態，音色，力感及細節等都會有較好嘅表現。

而一般以香港一般家居環境，加上用玩選用嘅AV AMP同Speakers嘅質素。喺由Auto Set Up情況下，要各聲道達75dB呢個標準，一般sound levels都會減幾個dB或以上。呢個同空間，AV AMP嘅推力都有關係。

所以Anthony一般會用另一個方法去set Sound levels。方法十分簡單，先將中置sound levels調至+/- 0 dB呢個水平，再用音壓計量度由中置輸出嘅音壓，最後以中置輸出嘅音壓為基準去調校其他channel。咁點解係+/- 0dB?點解要用中置係reference唔用前置，唔用後置?+/- 0dB係因為呢個數值係較為中性，而中置係單一喇叭，唔會出現左右喇叭大細聲而唔知跟左定右好嘅問題，而影片中70%音效嚟自中置channel，所以用中置為reference較為好啲。而用以上方法為Keith兄調校Sound Levels得出以下數值(Sound Levels 值為80dB):

C: +/- 0dB，L/R : + 0.5dB，SL: +1.5dB，SR: +3.5B，SW: -12dB

咁Sub-woofer呢?低頻多少真係好個人，有啲朋友喜愛大大力打心口，有啲朋友喜愛少少地震吓sofa。而Anthony一般set 低頻嘅準則係以最少反效果下得到最大震撼為目標。可謂反效果呢，如:因箱體限制而令單元拍邊、因某頻段出現嘅諧震同最緊要嘅鄰居投訴。

而為求刺激，好多時都會不自覺地咁不停加大sub-woofer音壓。所以Anthony一般會由最少做起。Anthony會先將sub-woofer嘅Sound levels同其他channel睇整為起點，再以家居環境同個人口味再微調。以Anthony為例，因家居環境同鄰居嘅忍耐力指數，Anthony嘅sub-woofer嘅Sound levels係比其他channel細7dB(以Cary Cinema 11A嘅pink noise 計算)。

以上面嘅方法為Keith兄套器材作調校後得出包括sub-woofer嘅所有channels嘅Sound Levels為80dB。

iwc

wadee 發表於 2014-2-1 21:05
我張吸音墊是買二手的，聽講西九龍廣場對面有，新的要六百幾，你可在76搜尋下資料～ ...

Thx !