FiiO D3V2 Mods
I performed a frequency response plot for my modded D3V2. The red response line is a Behringer USB DAC I used to obtain a baseline response curve. As you can see it is more or less flat from 20-20KHz. The blue response line is the D3. Yes it does roll off a little, about 3dB, starting at 10KHz. I doubt that is audible. Certainly not many loudspeakers are any better. Not bad for 20 bucks or so.
Gauging form the number of comments on the “Inside FiiO D3” post, it seems there is a lot of interest in this low cost device.
Mr Scott sent me a few photos of his modded D3V2. The FiiO D3V2 is the infamous version that many complained of having rolled-off highs. But according to Mr Scott,
My experience with the D3 V2 is that I did not have any complaints with the stock unit that I received. After the mods it has definitely improved with regards to clarity and soundstage. Even though I have 56 year old ears, I’ve been a musician for about 40 years, I design and build top end hi-fi tube amps, and have been a discerning listener for a long time.
Thus, contrary to others experiences, this device seems to operate properly. In any case, here are the photos of his modded D3
Also replaced the zener 3.3V regulator with an ST Microelectronics LE33CZ 3.3V regulator.
If anyone else wants to do this, you must remove the zener as well as the two 75 ohm paralleled resistors that are connected to the cathode of the zener. Then you connect the ground of the LE33CZ to the pad where the anode of the zener was, the “in” of the regulator goes to where the two 75 ohm resistors were, nearest the edge of the circuit board. The “out” of the LE33CZ goes to the pad where the cathode of the zener was.
Here is a closeup of the 3.3 regulator
After listening to this with the mods, I can say that the stereo separation and “spaciousness” (for lack of a better word), has definitely improved.
BTW, Mr Scott is “Scott17” at diyaudio [link]