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I have Iphone 15 pro max and beyerdynamic DT770 PRO 80ohm, can I drive this headphones with this dac in normal mode ? I am planning to buy IEMs or some portable headphones in the future , any suggestions ?
But how does FiiO KA17 achieve 4.5 Vrms = 12.7 VP-P (4.4mm, desktop mode, high gain) then?Voltage swing determine how loud the headphone can get. However, don't forget KA17, even when powered by external Type C source, still operates on a 5V USB power rail. Generally the quickest way is to flip the USB power rail into +5V / -5V rail which that amp section can work to generate a voltage swing between that. But since some power will be wasted to generate the + / - voltage rail, you won't be getting the whole +5V / -5V but less. Most of the time manufacturers will instead opt to split 5V into +2.5V / -2.5V as it is easier to do when you don't need to up-convert the voltage, hence why you typically see less than 2V of output on USB audio devices and especially dongles. Anything more than +5V / -5V will increase noise and circuit size too much that likely won't worth the effort nor fit inside a dongle sized device due to the limitation of USB power. That why if you really need a lot of voltage swing, better look for a battery powered DAC/amp instead.
Perhaps I should be more clear - I am not saying it isn't possible to up-convert the power rail above +5V / -5V, but the higher it goes, the more difficult it will be. to keep the circuit in reasonable size/complexity to maintain a clean power. The way FiiO partially solves this issue is by introducing a second power source via a Type C port, but that's still limited to 5V nonetheless. If you look at FiiO old E12 series of portable amps, the best way to get a bigger and cleaner voltage swing is by stacking up multiple Li-ion batteries to get a higher starting voltage (11.1V = 3 x 3.7V, so three Li-ion batteries in series)). Another example is Mojo, which used a 7.4V ( 2 x 3.7V) battery pack. There is a reason why a higher starting voltage is generally preferred over an up-converting voltage because, at some point, the latter is much more difficult to get a good result than just stacking up batteries. The point is, it is not whether it is possible to do so or not, but what kind of design makes the best sense to the targeted audience.But how does FiiO KA17 achieve 4.5 Vrms = 12.7 VP-P (4.4mm, desktop mode, high gain) then?
Dear friend,I have Iphone 15 pro max and beyerdynamic DT770 PRO 80ohm, can I drive this headphones with this dac in normal mode ? I am planning to buy IEMs or some portable headphones in the future , any suggestions ?
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it might be better to ask about iem suggestions in the Introductions, Help and Recommendations Subforum. your beyers arent hard to drive by the way. depending on the volume you listen to even the Apple dongle could drive them. The KA17 might be better sounding regarding dynamics, tightness and soundstage tho.I have Iphone 15 pro max and beyerdynamic DT770 PRO 80ohm, can I drive this headphones with this dac in normal mode ? I am planning to buy IEMs or some portable headphones in the future , any suggestions ?
I have the p20 as well, I will test to see if I can find the same issue.After several tests to understand the reason for strong EMI noise when the KA17 is current powered, I found that the problem lies in the structure of the Shozy P20, which is an all-metal planar IEM. I tried all possible tests, even changing the cables (the data cable is the ddHiFi TC09S so the best possible) and there is no EMI with the other resin IEMs... this isn't nice because if I touch the jack handle it disappears, discharging with my body.
The only way to solve it is to use a power bank: no EMI.
The P20 sounds so good and warm... they pair amazingly with the KA17!
I have the p20 as well, I will test to see if I can find the same issue.
What cable are you using? is it balanced or SE?After several tests to understand the reason for strong EMI noise when the KA17 is current powered, I found that the problem lies in the structure of the Shozy P20, which is an all-metal planar IEM. I tried all possible tests, even changing the cables (the data cable is the ddHiFi TC09S so the best possible) and there is no EMI with the other resin IEMs... this isn't nice because if I touch the jack handle it disappears, discharging with my body.
The only way to solve it is to use a power bank: no EMI.
The P20 sounds so good and warm... they pair amazingly with the KA17!
It's a 4.4 balanced cable, but I tested also 3.5 SE and there was even much background noise... It can be completely solved with a power bank. I ordered a nice Remax 5.000mAh with direct plug on AE, but I'll receive it in 1 month (hopefully). So, I'm currently using the power bank that I already have with a long cable. Not very practical as you can see, but just for the moment.What cable are you using? is it balanced or SE?
Thank you, the frequent cut outs had also been puzzling me! I’ll try other cables!I noticed with the original cable that the sound will randomly stop, especially when I move the dongle a little bit. The trick with reverse cable swapping works, but temporary, so I decided to upgrade the cable.
Today I received DD ddHiFi TC05 Type C to Type C Data Cable to try it with my KA17 and I'm very happy to report no more disconnection or sound stopping. The original cable is not very good unfortunately. @FiiO please make better cables for your future dongles. I mean you guys put high quality silver plated cables on your iems but your dongles get the short end of the stick...
Back to the TC05, no sound improvements over the original cable if anyone is interested. A/B tests they sound the same to me, but that's my opinion. Reviews from my local store are saying that there is better sound with this cable, but I can't notice anything different over the original. All in all I recommend this cable with the KA17. If you guys have the cash to spare you could try the TC09S cable that is better quality although at a higher price. For now I'm happy with TC05.
Same here with the ka17 - swapped mine over with the cable that came with my earlier ka3 - no problems sinceThank you, the frequent cut outs had also been puzzling me! I’ll try other cables!