I’ve got the CrinEar Protocol Max and love it! I need another DAC/amp to use with my iPhone. I could just buy another but I’d rather get something else if it meets my needs:
Fosi MD3 looked really cool until I realized no PEQ. Same for Schiit Vestri.
I like Qudelix T71 but it has battery.
Fiio KA17, but PEQ through Android or Windows.
I should mention I have a Qudelix 5k. I hate the app interface, form factor, and the battery dependency.
Amazon listing shows iOS support.
So you’d want the DAC+amp to have its own power supply but still be somewhat portable?
KA17 works with iPhone, but iOS Fiio Control app doesn’t support KA17 (AFAIK).
Maybe the Plus version will fit your needs better:
Does the big one Crin makes have an app for the iphone? I mean you can’t expect great interfaces on these low end low volume devices. Why does the battery in the k5 bug you? You can run it plugged in? I have 2 5K and a questyle m15i. No eq on the latter. So I stopped using the eq on my k5 and started using the android and linux eq tools. I don’t know what the iphone works with so hard to answer on that end. I mean Crin seems to think that plain old apple dongle on iphone is pretty darn good for most iems. I do think the m15i feels more polished then the 5K but it does like 1/4 or the stuff. I can see how DMS went for a year with just the m15i. I haven’t used my desktop amp much since I bought it. Only recently turned it on to use the dac and preamp controls on my desktop.
I think the high end fiio is the thing that meets your specs. Not the battery/5k clone but the dongle only. I think it has a built in EQ tool. I don’t know what platforms it works with. And I can’t remember the number scheme but I think it was like $175 when I was cross shopping it against the questyle. I would have bought it but the questyle went on sale.
No. I want it to be powered from the phone rather than having it’s own power supply. Like the CrinEar Protocol Max.
I’m not completely sure but I don’t think the Qudelix will work without a minimum charge on the battery. I seem to remember getting caught out once because I don’t use it daily, the battery drained, and I couldn’t get it to work over USB until the batter charged up a bit.
There is definitely some weirdness around using it via USB. I think the app needs to communicate over Bluetooth even if it is plugged in to the phone. I also have issues with it connecting/prioritizing Bluetooth when I want to use it over USB. This is despite changing the connection priority settings in every possible combination.
So I am a bit wary of any product that lists Bluetooth as the primary connection. I don’t want Bluetooth. I don’t see the point in this context as it doesn’t give me true wireless. IE there is still a wire from the headphone to the Bluetooth DAC/amp. Not to mention Bluetooth devices have the extra cost and complexity of a battery power supply that I don’t want.
I just tried it. Audio works over USB-C after turning off BT on the phone but the Qudelix app only works via BT.
The desktop Chrome extension works over USB though.
Outstanding audio quality that matches the CrinEar Protocol Max, for about 35% of the cost. With EQ. Based on very similar DAC chips and I would say even more accurate than the Crinear Protocol Max, whose main differential is the use of a headphone amplifier chip to increase the power.
This is the TRN Black Pearl which uses two CS43131 DAC chips which have an in-chip headphone amplifier, so should be quieter spec wise than the Protocol Max, in theory. Excellent DAC. With outstanding technical specs. and on board EQ for $35 approx. Has single ended, and balanced outputs.
A no brainer purchase.
has too many features to list here.
Please google.
It is one of the best dongle implementations with Dual CS43131 DAC chips.
I have been using a similar device, with dual CS43131 DAC chips, the TempoTec Sonata BHD, for two years, the technical specifications are similarly exemplary, even better than many desktop DACs, but this does not have an EQ. WIsh I had realised I may need EQ, and would have bought the TRN Black Pearl. It is possible the Black Pearl was not yet available at that time.
More info here, for the geeks
I am confused about this post? Maybe edit for clarity? Are you recommending something?
Isn’t that the weirdest thing? And yeah in linux pretty easy to pick the usb connection but not sure on the iphone if selecting one over the other is so simple… I get it. But honestly the only reason I see to not have bluetooth is for hard to drive stuff. I know it makes me a looser but I don’t think I am typically doing detailed listening on the go.
Luxsin will also launch a new portable DAC, the Luxsin P8. Not sure if it will have EQ. At the end of the video it is shown.
TRN Black Pearl, excellent audio quality, for very little money. Dongle DAC, with too many features to list here, if one needs a dongle DAC with on-board EQ. Responding to the thread starter.
That Luxsin BH9 and BD9 stack is really cool! The P8 looks a bit much and I’m trying to avoid batteries.
I think I have it narrowed down to either the Fiio KA15 or the Cayin RU3. Honorable mentions to the Fosi MD3 and Schiit Vestri, which lack EQ but are otherwise really cool.
The MOONDROP MoonRiver 3 is also tempting, mainly because it has a volume knob. But it is expensive.
The big question for me is whether the Cayin iOS software is any good. I really should just get the Fiio KA15 because its software is mature but I just can’t get excited about it. It just looks cheap tbh.
Have you looked at SnowSky Melody?
No but I am now! 
I like the design enough that even though the KA15 and RU3 have a screen, I might go with the Melody.
I’ll need to do some calculations to make sure all of these choices are powerful enough for full size headphones.