已出

yupoet

交易区新帖推荐

已出

[ 本帖最后由 yupoet 于 2011-12-11 15:13 编辑 ]

yupoet

规格参数

C-2.1   Specification

Improvement may result in changes in specifications and
design without notice.

　
　     
Head amp / Preamp
　
S/N Ratio     
117db (Input short)
　
Output Level     
10V RMS
　
Output Power     62 ohm: 1000MW
100 ohm: 1000MW
300ohm : 330MW
600 ohm: 165MW
Gain     
4DB (Gain setting L)
13DB (Gain setting H)
　
Volume Characteristic     Applied I/V change volume control
Output Impedance     
1.5 Ohms (HP amp)
　
Input Impedance     
47K Ohms (RCA input)

2 Ohms (ACSS input)
　
Frequency Breadth     
2Hz to 130KHz (ACSS input ,1V output level)
　
Power Requirement     
1 Version  100-130V  AC 50/60 Hz
2 Version  200-260V  AC 50/60 Hz
　
Power Consumption     
18W Class A
　
Operating Temperatures     
-10 °C to +80 °C
　
Operating Humidity     
5 % to 90 % (without dew)

yupoet

听感可以参考：
http://www.head-fi.org/search.php?search=C2.1

这里有篇大作，介绍C2.1前身C2的：
http://www.head-fi.org/forum/thread/483899/review-of-the-audio-gd-dac-19-dsp-c2-amp-the-acss-connection

其中描述C2系列的特性如下：
The C2 headphone amp/preamp:

Inputs:

The C2 has 3 inputs: 2 RCA inputs and 1 ACSS input. The RCA and ACSS inputs have different signal paths.

The RCA input has to go through a buffer stage. The stock opamp is the OPA604 but audio-gd offers different discrete opamps (I ordered mine with both the Earth and Moon opamps).
The gain setting is effective only on the RCA inputs and you get to choose between the +4db and +13db settings on the front panel.

The ACSS is a more direct path. The signal doesn’t go through the buffer stage and is not affected by the gain settings on the front panel. When connecting the dac19 with the c2, both units act as a single one and there is one gain stage at the c2 level. This avoids the redundant gain stages and impedance mismatches that happen in the classical RCA connection.


Current gain and volume control:

As described for the dac19, the C2 uses the current gain technology, which allows audio-gd to have a very linear circuit design without resorting to negative feedback.

The volume control is very different from conventional systems (whether using traditional pots or stepped attenuator). Here the signal doesn’t go through the volume pot but rather the volume pot acts as a reference for the current gain. So the C2 is in fact an amplifier with variable gain.


Power supply:

The C2 amp has a similar oversized power supply philosophy as the dac19. The C2 uses a 50 watts R-core transformer (which is better suited for audio than toroidal according to many designers), and a lot of separate filtering.


Overall:

While the C2 has some nice features (discrete design, current gain, zero feedback ...) it doesn’t reach its full performance until it is used from the ACSS connection and paired with the dac19.

we520

帮顶了！

yupoet

谢谢WE兄

转载翻译一篇head-fi上的听感：

                                                                                                                        I tried my combo DAC 19-DSP + Audio-GD C2 (with OPA Moon when i made the test) with a Grado RS-1 (not mine), first i made a try with ACSS the result was satisfying : Big Bass well controlled, C-2 has good "grip" on it, medium was extremely pleasant, detailed and smooth and slightly colored (on some cans medium tend to sound too "metallic" or "woody", on the RS-1 it was just perfect), highs were smooth and extended but with a bit more "crunch" than all other Headphones i tried, but it was the first time i was listening a Grado...

        My friend (the owner of the Grado) put it on his head and tell me that the sound was very good (he use to listen the RS-1 on his rig : Cambridge Dac Magic + Head-Amp Ray Samuels Audio HR-2), and then we tried both with the Moon OPA, i find the sound different but not better IMO : with the Moons the bass was more "chesty" and gave a better sensation of deepness but was also a bit more "boomy", the medium was slightly more colored and the highs sound more "rounded" (soundstage seems also a bit wider).

        My friend preferred the sound with OPA Moon and tell me it was excellent, and I tend to prefer with ACSS because i found it more accurate...

        The test was done on the track "So what" from the Album "A Kind of blue" and some various other pop/rock songs.

        The end of the story was : two days ago, i bought a Grado

原文在此：

http://www.head-fi.org/forum/thread/542943/audio-gd-c2-1-and-grado-rs2i-match-made-in-heaven-or-keep-looking


“我试过用DAC19DSP + C2 （换了moon OPA）来推歌德RS1，首先我用的是CAST传输链接，结果满意：大量的低频得到了很好的控制，C2对低频的掌握很好，中频是极度的让人愉悦，充满细节、顺滑、有点点染色，在其他“耳机？”上有些金属味和木头味，在RS1上刚好完美，高频顺滑、延伸出色，此外与其他耳机相比有一些"咯吱”声（译者按——这里是说明C2系列耳放的高解析性。我在配合GMP450pro使用过程中，可谓分毫毕现）

我的朋友告诉我，这个声音十分好，他以前用的听音组合是剑桥DAC Magic+Head-Amp Ray Samuels Audio HR-2。然后我们又切换到Moon OPA来尝试（译者按——CAST传输时候不适用OPA，普通RCA传输时候应用到moon OPA）我发现声音有些不同，但也不能说更好。在使用Moon OPA （RCA输出）的时候，声音显得更为丰满，有一种更深的感觉，有点更“汹涌？”，中频染色稍多些，更有包围感，声场更宽。


我朋友更喜欢Moon OPA并且觉得这个声音很棒，而我则更喜欢CAST电流传输，因为更准确。

                                                                                                                                                               
测试曲目是专辑“a kind of blue"里面的“So what” ，以及一些流行、摇滚歌。”

yupoet

已定出，谢谢各位

戏子

好东西