兩聲道
CD機 | MD機 | SACD機 | DAC | CAS | 合拼擴音機 | 前級擴音機 | 後級擴音機 | 接線 | 喇叭線 | 揚聲器 | 耳機 | 耳機擴音機 | LP產品 | 膽機產品 | 開卷式錄音機 | 音響配件 | DIY音響 | 電源 | 家庭影院
電視機 | 投影機 | 錄影機 | DVD影碟機 | Blu-ray影碟機 | 多媒體播放器 | 機頂盒 | 多聲道擴音機 | 多聲道揚聲器 | 多聲道影音組合 | Mini音響組合 | 重低音揚聲器 | 輔助設備 | 同好會
同好會 | Accuphase | B&W | Burmester | Denon | Jadis | KEF | KRELL | Luxman | Marantz | Nuforce | OPPO | Pioneer | TEAC | WEISS | News
News | Blog | 其他
其他 | 所有 |
| 影音天地主旨 ﹝請按主旨作出回應﹞ 上頁 下頁 首頁 尾頁 | 寄件者 | 傳送日期
|
| [#21] 無低音的真正元凶-----駐波 聲音的波長是隨頻變化，不能以單一頻率波長作準。 只能盡量避開長寬高都相同的反射波長。 |
孟波 正式會員218.xxx.xxx.240 |
2009-05-06 22:27 | |
|
|
|||
| [#22] 無低音的真正元凶-----駐波 not exactly, you can read more here..... http://www.lyngdorf.com/index.php?option=com_content&task=view&id=85&Itemid=35 |
ackcheng 正式會員 218.xxx.xxx.128 |
2009-05-06 22:28 |
| [#23] 無低音的真正元凶-----駐波 ackcheng, ""Tact believe placing the woofer next to the wall expecially at the corner will help. """ That's exactly what I am now seriously considering. My listening room, with the speakers being placed about 8' from the front wall, has a steep rolloff at 50Hz (thanks to Dr. King for doing the measurement for me) and then peaks up at 30Hz. That lost frequency would come back obviously along with the moving of the speakers closer to the wall. So, there must be some cancellation effect. However, I enjoy very much the clarity of the sound, the imaging and depth of the sound field produced by the speakers at where they are. So, what left can be done seems to be adding a sub-woofer at the wall to supplement the the lost frequency produced by the main speakers. |
thomasc2 正式會員 218.xxx.xxx.151 |
2009-05-06 22:28 |
| [#24] 無低音的真正元凶-----駐波 搬下張櫈仔,得唔得? |
rickymartin 正式會員 116.xxx.xxx.48 |
2009-05-06 22:30 |
| [#25] 無低音的真正元凶-----駐波 rover, """so if valley in low frequecy occurs in a room, makes the bass weak, adding a sub seems not a solution, as the frequency will also be cancelled by refection wave....."""" You certainly would not place the sub woofer at the same position of the main speakers. At a different position, usually close to the wall or at the corner as ackcheng suggested, the cancellation effect to the subwoofer would then be different from that affects the main speakers. |
thomasc2 正式會員 218.xxx.xxx.151 |
2009-05-06 22:32 |
| [#26] 無低音的真正元凶-----駐波 thomasc2, this is exactly what I hope to do recently. I tried to merge my SVS sub into my stereo system. But the result is less than satisfactory...I find the spk's original sound(which I like very much) changed after adding a sub...maybe I need some very detail and accurate measurment before doing this, and I think maybe a independent crossover is required for more accurate seperation of frequency?(I just connected my sub with RCA cables from my pre amp's 2nd output) |
rover901 正式會員 202.xxx.xxx.140 |
2009-05-06 22:45 |
| [#27] 無低音的真正元凶-----駐波 Adding a sub woofer to the main system can be tricky. As you need to take into account the delay as they are now in different position. The phase shift will also be a problem. When you place the woofer at the corner, you basically have a horn! and you may need to lower the amplitude too |
ackcheng 正式會員 218.xxx.xxx.128 |
2009-05-06 22:49 |
| [#28] 無低音的真正元凶-----駐波 Time delay and phase shift are areas of concern - Flat curve but bad sound. Why not 1. relocating the speakers, 2. adjusting the toe-in angles, 3. moving the chair, to an optimal point? You need to change all three varibles instead of one or two. It is very time consuming but worthy to do it. At that optimal point, the sound curve at the listening position should be the flattest. Using an EQ to tame the small sound peaks if it is needed. |
rickymartin 正式會員 116.xxx.xxx.48 |
2009-05-06 23:13 |
| [#29] 無低音的真正元凶-----駐波 hi rover901, the test CD is ready for you, pls contact me. you may measure your room to identify problem first. I doubt your problem is really due to dip in the room. |
m40 正式會員 113.xxx.xxx.155 |
2009-05-06 23:19 |
| [#30] 無低音的真正元凶-----駐波 嘩~!後日會去睇下~~好似幾正咁WOR |
siuwing 正式會員 218.xxx.xxx.88 |
2009-05-06 23:32 |
| [#31] 無低音的真正元凶-----駐波 very interesting! But we have to clarify: 1. what is stationary wave? 2. Under what condition a stationary wave can be formed? (in fact, stationary wave is not that easy to form!) 3. Besides stationary wave, interfernce plays more important role in stereo setting! When we think over above, stationary wave is not the main reason of "no bass". |
lts300 正式會員 210.xxx.xxx.123 |
2009-05-06 23:37 |
| [#32] 無低音的真正元凶-----駐波 if u want to know more, u can refer any physics text book in secondary school. |
lts300 正式會員 210.xxx.xxx.123 |
2009-05-06 23:39 |
| [#33] 無低音的真正元凶-----駐波 one more point: What will happen when a stationary wave is formed? |
lts300 正式會員 210.xxx.xxx.123 |
2009-05-06 23:54 |
| [#34] 無低音的真正元凶-----駐波 """When we think over above, stationary wave is not the main reason of "no bass".""" Yes, you are right. Stationary wave is not the reason of "no bass". If you read carefulfully the explanation notes I posted above, you should notice that stationary wave refers to that reflecting wave what causes the "peak", but not the valley. It should be another type of reflecting wave that eats up the bass. But there seems to be no specific term for that kind of reflecting wave. I just apply the title of the model used by museum to this thread. I probably should't have done so.  |
thomasc2 正式會員 218.xxx.xxx.151 |
2009-05-07 00:01 |
| [#35] 無低音的真正元凶-----駐波 wave can not be "cancelled" by his reflection wave! wave can be "cancelled" only by another identical wave with out of phase! --＞ This is the thoery of noise reduction head phone. |
lts300 正式會員 210.xxx.xxx.123 |
2009-05-07 00:13 |
| [#36] 無低音的真正元凶-----駐波 rickymartin ching, u are talking about interference, not stationary wave! |
lts300 正式會員 210.xxx.xxx.123 |
2009-05-07 00:20 |
| [#37] 無低音的真正元凶-----駐波 yes again. Both the peak and valley should be caused by reflecting waves. depending on the distances between the speakers, reflecting wall, listening point, 'frequency/wave length etc., the reflecting wave can be 0 degree in phase of the main wave or 180 degree out of phase of the main wave. If it is in phase, it adds up and creates a peak. If it is out of phase, it cancels and makes a valley. |
thomasc2 正式會員 218.xxx.xxx.151 |
2009-05-07 00:22 |
| [#38] 無低音的真正元凶-----駐波 """"wave can not be "cancelled" by his reflection wave!""" Why not go and see by yourself how it works! |
thomasc2 正式會員 218.xxx.xxx.151 |
2009-05-07 00:32 |
| [#39] 無低音的真正元凶-----駐波 thomasc2 hing, I guess Its300 refers to the terminology that you've used. "Cancel" is not the correct term. It should be "destructive interference" that caused the reduction of amplitude. |
xyz_ps 正式會員 203.xxx.xxx.173 |
2009-05-07 00:35 |
| [#40] 無低音的真正元凶-----駐波 rover901 hing, if you read Stereo Sound carefully, they only encouraged to use EQ or room treatment (absorption) to suppress the peak but not to pull the valley with EQ for room acoustics. I also recall in an article in issue no.169, the author who used JBL K2 also mentioned how to get rid of the 60Hz valley in a room by setting up the speakers along the longer side of the room (曰), contrary to the "common concept" of having speakers set along the shorter side (日). The idea was to boost the overall bass to almost booming with the shorter room depth and then reduce the excessive bass by absorption or EQ suppression. |
xyz_ps 正式會員 203.xxx.xxx.173 |
2009-05-07 00:45 |
