Ok so, I did a test. I'm confused. I need your input to figure out what's happening. I mix and match 3 DAC/AMPs with 2 IEMs. The question I have is that, if DAC/AMPs are supposed to be transparent, aka outputting a flat FR, what else can affect the tonal balance in the chain?
Gear list:
HIFIMAN EF600(Low Gain NOS), Cayin RU6 NOS, FiiO BTR7
Truthear Hexa, Moondrop Aria 2
I tried my best keeping all the volume same, vocals especially. The EF600 has A LOT more bass than the other two, but also having a much clearer instrument separation and clarity, by a great margin. BTR7 has somewhat good bass while RU6 has the least. RU6 has the least clarity as well.
I know this may sound obvious, "Duh, DAC/AMPs are different." But I'm wondering the root cause of this, like is it because they output different non-flat FR? Or is it the output impedance that's affecting the sound? I specifically used two IEMs with different setups, single DD and 1DD+3BA, the results are exactly the same so IDK if it is impedance. I'm curious what's behind this. I know RU6 has very bad THD so a lack of clarity can be explained. BTR7 has better THD on paper than EF600 but the actual perceived clarity is audibly lacking. It could be IMD or something else but the drastic difference of tonal balance is beyond my understandings.
I have the RU6 and RU7, and they both lack clarity and resolution when I drive them with through my laptop with the stock cable. Oddly, they both sound best through my iPhone connected with a DDhifi09s lightning cable, the muddiness clears up and everything is crisp and detailed.
I'd pick up a DDhifi usb-c to usb-c or usb-c to lightning cable and try it. If you get it from Amazon you can just return it if it doesn't work, but it was a big difference for me. I've also heard of people using USB purifiers to handle the noise.
Are you sure it's not placebo? As far as my understanding goes, it's technically impossible to have "sound quality" variance on a digital cable. It's just ones and zeros. If it fails to transmit the signal as it is, it will probably click and pop. Analogue cables could sound different because of their impedance.
Definitely not placebo, the difference is as clear as day. Most cables transmit power and data through the same wires, the DDhifi cables split the usb power and usb data into two separate, shielded paths.
I love how redditors want everything to a placebo so they don't have to spend more money. 😂
Oh please don't assume that. I've spent a lot of money and I don't mind. I will try the cable. It never hurts to try something new. At least for me, it's not saying everything is placebo. It's because placebo plays a huge part in this hobby, so keeping in mind of its contribution is always a good idea when looking for something more objective.