Saturday, February 16, 2008


Finally bite the bullet and got myself a DAC. Well, an USB DAC to be exact. (Anyway, my main concern is on the DAC part. The USB sound card in it is just a bonus :P)

It is the Mini USB DAC by Granted, it is not the best DAC out there. But given its price (< HKD900), it is tough to beat in its own class.

This DAC is based on the Texas Instrument PCM1793. And rumor said that the headphone amplifier part is a clone of the Solo.

But to my ears, my DIY PIMETA sounds much better that the built-in headamp.

On the left is my DIY PIMETA headphone amplifier, with Analog Devices AD843 op-amps installed. (If you love pop/vocal and is not a bass-head, I strongly recommend the AD843 op-amp. It might not has the details of the OPA627 / OPA637, but the tone produced by AD843 beats them all (even the OPA2111 that I have can't beat the AD843).

My current setup is: Pioneer DV-636D -> (S/PDIF) -> DAC -> PIMETA. The S/PDIF cable is a Canare cable. There were debates on the net that whether a RCA cable can really make a real 75 ohm coxial cable. But nevertheless, this Canare cable with the designed plugs seems to be doing fine... at least to my ears (These Canare plugs require a special crimp to assemble the cable... so I bought this interconnect directly from a studio shop).

The analog RCA interconnects are DIY ones made from Swiss Gotham GAC-1 cable with Canare plugs.


cc said...


kc said...

The 牛奶妹/牛奶仔 etc are amplifiers. They amplify the sound and provide volume control etc functions.

DACs (digital/analog converters) are something else. They convert digital signal (e.g. those zeros and ones read from a CD disc) into analog signal which human can listen to.

So a general setup would be: CD transport -> DAC -> amplifier -> headphone

cc said...

咁 ... o的手提CD機(未駁headphone時)係咪即係= CD transport + DAC + amplifier 呀?

kc said...

係呀~ 手提機例如 discman 因為要方便用家,所以除左有光頭讀 CD 上的數據 (即係 transport 果一part),仲有內置 DAC 同 amplifer。咁用家直接插上耳機就有得聽音樂。

有o的手提(或者大部份o既座檯) CD 機種會有所謂 "line out" 輸出。意思係唔經內置o既 amplifier 出聲。即係只用內置o既 transport 同 DAC,跳過 amplifier 一欄。係咁情況之下,失真會少左,不過就失去左用內置音量調節器o既功能。用家可以用外置o既 amplifier (例如你見過o既「牛奶妹」) 做信號放大同調節音量。

咁再有o的機為左俾用家有更多選擇,又或者「x忽痕」時有野玩,可以將由 CD 光頭讀到o既數碼數據直接輸出。咁用家就可以自行配搭 DAC 同 amp。