翻译了一片老外做 8545+9300的资料,兄弟们帮分析

ardun

发现一篇文章,翻译了一下,水平有限,我用的同样分频及单元.但是用的34升的倒相箱就是那个贵族2.5的,感觉中高音不错,低音听炎黄第一鼓时鼓声的现场感很强,量足但是每一声鼓后都有轻微的回声,
播放大动态音乐例如平克弗洛伊德的墙1, 感觉大动态时有点低音乱,不结实.
低音的松软是我喜欢的,下潜也很深,就是大动态乱不喜欢.本人不是金耳朵,请大侠们看一下这位老兄的分析.再分析一下我的箱子症结所在.



Making of M1
By Man-Sun Huh
20 Jan 1998

制作M1
1998 1月20号

System Introduction
2-Way closed box speaker with Scan-speak units. This speaker system is designed for near field monitoring in small rooms ("M" for M1 means Monitor) and for reproducing clear images. I selected a closed box system. Though "M1" has restricted bass, it can deliver more articulate bass response than any other bass-reflex system. In my room (about 20 square meters), it can play chamber music, jazz and pop with satisfaction Fig. 1. Picture of the M1.

这是一个2路闭箱系统,设计用来在小空间里左监听使用,M1意思为监听的意思,我选择了闭箱,所以M1的低音受一定约束,但是它比其他低频设计有更好的低频响应,在我20平米的房间里,可以播放轻音乐爵士流行音乐等
Units

低音 Woofer: Scan-speak 18W/8545 7" paper cone with carbon fiber

This ia an amazing mid-bass unit from Scan-speak Fig. 2. The drivers. It has a sufficiently low bass response and makes me possible to make a closed box system. Its sound is very clear and wide in midrange but need some network technique to control some gentle bump (300-1000 Hz) in the midrange. This unit and some revised versions are used in many well known commercial speaker systems (Wilson WATT5, ProAc 2.5 etc.). The Thiele-Small parameters of specification and test results are:


这是一个令人惊奇的中低音单元,它有很好的低频响应所以我可以用来做闭箱,他的声音层次分明及声场较宽,但是需要设计分频控制300-1000的峰,这个单元和其他版本的用在很多著名的音箱上.具体参数如下


Parameter                    Listed    Measured
-----------------------------------------------
Sensitivity (dB/1m 2.83V)      88.0        87.8
Free air resonance (Hz)        28.0        31.6
B x L (Tm)                      7.2         7.9
Moving mass (g)                19.0        21.7
Qms                            2.41        2.35
Qes                            0.35        0.39
Qts                            0.31        0.34
Vas (Liter)                    54.0        37.1


高音 Tweeter: Scan-speak D2905/9300 28mm soft dome

It's another amazing tweeter from Scan-speak Fig. 2. The drivers. And It's updated version of the legendary D2905/9000. Though not cheap, I can say it has very high cost performance. It's dynamic range is beyond expectation for soft dome and well match with 18W/8545.
Cabinet and network
Cabinet drawing showing the front and side Fig. 3. Cabinet drawing .
I wished system Qtc around 0.577 (Bessel Alignment). This low Qtc can give very detailed response what I like. The optimum volume was 16 liter but I designed internal volume 20 liter and Qtc is measured 0.53. The network will raise Qtc somewhat.
这是另一个令人惊奇的高音,它是9000的升级版本,尽管不是很便宜,但我可以说它很超值,它的动态范围远超过了对软顶高音的期望值并且非常适合8545
箱体分频
我希望系统的QTC在0.557,这种Q值可以给我喜欢的细节响应,最合适的体积是16升,但是我设计内部20升,此时q值是0.53,分频网络将会提升Q值.



Network
分频


Here are some criteria for network design:
分频设计有一些标准
1. The simpler, the better. Only 8 elements are used. In tweeter signal path, single capacitor and resistor are used for pure sound.
2. Low crossover point (1800Hz). It can deliver a wide dispersion. But it need reliable tweeter such as D2905/9300.
3. Acoustically 4th. order Linkwitz-Riley filter slope around crossover point.

最好的简单的是使用8元件,在高音设计里,用一个电容和电阻得到纯净的声音
分频点1800,可以让频宽较大,但是必须配合9300


Test Results
Anechoic response of system Fig. 6. Anechoic response. Sensitivity is around 84dB/2.83V and -6dB point in bass is about 47Hz. It is very satisfactory result for small speaker. It's bass roll-off is about -8dB/Oct. With room enforcement in bass, this speaker can reach down to 40Hz.
Impedance of system Fig. 7. Impedance. Minimum impedance is 7 Ohm and it's a very kind load for amp. No wrinkle in graph shows good restriction of cabinet vibration.

Anechoic response of each unit Fig. 8. Anechoic response of each unit. Anechoic response when tweeter polarity is reversed Fig. 9. Anechoic response with tweeter polarity reversed. Well designed crossover must show steep dip at crossover point and M1 also shows steep dip.

测试结果
响应曲线见图六, 灵敏度84DB,-6db低音约47HZ, 这是令人欣慰的结果对这个小箱子来讲,同方房间加强低音会到40HZ.
阻抗曲线见7, 最小为7,曲线比较平说明了箱体振动被有效限制了.

Sound

For my experience, It need more than 2 weeks of burn-in. And It's bass improves dramatically during burn-in. It's sound is well balanced. It make me feel comfortable and I can't hear any booming sound in bass. Finishing my project, I sold my $2,000 speaker system.

以我的经验,需要2星期煲箱,煲箱后低音改变了,比较平衡.而且低音里没有任何的干扰声,完成了这个箱子,我卖了我原来2000美元的箱子.
Part List
Units
Tweeter Scan-speak D2905/9300: 2 ea.
Woofer Scan-speak 18W/8545: 2 ea.

Capacitor
Cresendo 5.0 uF: 2 ea.
Zen (10+2uF): 2 ea.

Resistors
Ohmite 10.0 Ohm 10Watt: 2 ea.
Ohmite 5.0 Ohm 10Watt: 2ea.

Coils
North Creek Air-core 2mH 14AWG: 2 ea.
North Creek Air-core 1.2mH 14AWG: 2 ea.
North Creek Air-core 0.7mH 18AWG: 2 ea.


Miscellaneous

Dupon Dacron: 24 oz. (12 oz. per box)
Back cup: 2 ea.

Specification

System: Closed box 2-Units 2-Way system
Drivers: 28mm soft dome tweeter (Scan-speak D2905-9300)
7" Paper cone with carbon fiber (Scan-speak 18W/8545)
Crossover Frequency: 1800 Hz
Sensitivity: 84 dB (1m/2.83V)
Impedance: 8 Ohm (Minimum 7 Ohm)
System Resonance: 47 Hz
Frequency range: 47 Hz - 20 KHz
System Damping: 0.53
Size: 470 x 230 x 350 mm (H x W x D)
Weight: approximately 16Kg/each
Man-Sun Huh



--------------------------------------------------------------------------------

Figures
Fig. 1. Picture of the M1





Fig. 2. The drivers





Fig. 3. Cabinet drawing





Fig. 4. The crossover network





Fig. 5. Picture of the crossover





Fig. 6. Anechoic response





Fig. 7. Impedance





Fig. 8. Anechoic response of each unit





Fig. 9. Anechoic response with tweeter polarity reversed

ardun

谢谢版主鼓励

hya1951

兄台的箱子是8535用的,对于8545容积34L太大了，低音不好控制,根据我DIY的结果,建议减到25L左右,倒相管调谐在38Hz左右(阻抗谷点),功放的驱动力要大,内阻要低,分频电感直流电阻要小于0.3欧.如此改动后,低音极好,松弛,下潜深,又很清晰.

ardun

谢谢兄弟指点

hya1951

老外的8545是涂胶版的,和现在的不一样,参数也不同

ardun

回楼上兄弟,昨天调了里面加了硬pvc泡沫然后上面加了沙袋,约25升现在,天晚了没有大声听
小动态变化不大,但是似乎感觉那种低音的泛音应该少了一些

michaelkkk

有一定的借鉴价值。。谢谢楼主！！！

hya1951

原帖由 gnix 于 2009-4-3 09:29 发表
我也是用的这个大喇叭。声音不错的说。低频松弛深沉。

我们都是用8545的 ,感觉都不错,不过这个单元最近在坛子里被攻击得厉害,说什么8545声音脏什么的 我们用家怎么没有感觉到

ardun

说实话,一个单元能够有这么长的生命力不是吹出来的.老外这个帖子是从1998年写的到现在11年了,我用音乐传真120.2(坛子里的)来推,低音对我的印象是最为深刻的,松软,弹性十足.

最开始从自己做箱体,然后接了对垃圾分频,然后自己搭了一个后来被坛子兄弟里称为js的垃圾的分频,再后来做了这个帖子里的分频.在中小音量下真的很不错(喇叭是DX的,自己亲自去背回来的).
但是自己是菜鸟, 照猫画虎还行.

自己没有听过很顶级的器材.对我等菜鸟来讲,就是一点点试,不说仿谁的,在各位坛友帮助下,把声音调到自己喜欢位置,实际上最终追求的不是什么声什么声,而是自己喜欢的声音.谢谢各位,
各位大侠不肯贴一下自己的箱体容积,分频结构么? 互相交流.

ardun

我用EL34单端推,当然音量比较小的时候,效果还不错,和石机感觉就是不一样,但是不能开大音量稍大点低音就破了.
声音是有点慢的,我喜欢慵懒的靡靡之音

ardun

忘了补充,现在调到25升体积,导向管没有换.是 直径70长130的,按照25升38HZ算似乎应该是50直径长100的

hya1951

原帖由 ardun 于 2009-4-3 12:42 发表
忘了补充,现在调到25升体积,导向管没有换.是 直径70长130的,按照25升38HZ算似乎应该是50直径长100的

我现在是24L,直径60mm,长120mm.按公式计算不是很准的