hello,
i tried now around 10-15 different dacs and specially recently some really nice sounding not much costing devices come around
somewhat recently i found out that i really like the sound of the black lion audio revolution 2x2 interface, then 2 weeks ago i was looking for the first time into portable dacs (not much of a on the go listener, im looking into this for desktop use), tried the moondrop dawn pro (good for the money, but overall compared to more expensive amps not a endgame solution), then bought the Fiio KA15 ... much better imo and actually pretty close to the black lion audio interface (maybe/probably a Cirrus Logic Dac chip thing, which i also wanted to confirm as the moondrop dawn pro relys on CS413131 and the fiio KA15 on CS43198 + OPAMP (i upgraded to KA15 since the base sound of the moondrop dawn pro wasnt sounding bad, it was just a bit thin/brittle sounding which you usually get with small amps)
not just sound quality seems top notch on the Fiio KA15 but also its featurset, the dac chip seems well implemented you even get a class AB or H mode option (which is a function of the dac chip made accesible by fiio), also all digital filters are selectable
So, since the chip seems well implemented, i was wondering, can this thing be used as a base to DIY something? the recent collection of portable dacs measure pretty similar to desktop units to be honest
i already hooked it up to my active speakers via a 3.5mm to 2x cinch and also can confirm here, it sounds pretty good (but good usb filtering seems still beneficial, had to use a isolator since there was audible noise over cinch)
would it be possible to use this as a frontend and build a "output stage" for it? the output opamps are SGM8262-2 inside KA15, not sure how these react to high impedance loads, does anyone know more here? i just assumed if it can drive low impedance it can definitely drive high impedance...
i tried now around 10-15 different dacs and specially recently some really nice sounding not much costing devices come around
somewhat recently i found out that i really like the sound of the black lion audio revolution 2x2 interface, then 2 weeks ago i was looking for the first time into portable dacs (not much of a on the go listener, im looking into this for desktop use), tried the moondrop dawn pro (good for the money, but overall compared to more expensive amps not a endgame solution), then bought the Fiio KA15 ... much better imo and actually pretty close to the black lion audio interface (maybe/probably a Cirrus Logic Dac chip thing, which i also wanted to confirm as the moondrop dawn pro relys on CS413131 and the fiio KA15 on CS43198 + OPAMP (i upgraded to KA15 since the base sound of the moondrop dawn pro wasnt sounding bad, it was just a bit thin/brittle sounding which you usually get with small amps)
not just sound quality seems top notch on the Fiio KA15 but also its featurset, the dac chip seems well implemented you even get a class AB or H mode option (which is a function of the dac chip made accesible by fiio), also all digital filters are selectable
So, since the chip seems well implemented, i was wondering, can this thing be used as a base to DIY something? the recent collection of portable dacs measure pretty similar to desktop units to be honest
i already hooked it up to my active speakers via a 3.5mm to 2x cinch and also can confirm here, it sounds pretty good (but good usb filtering seems still beneficial, had to use a isolator since there was audible noise over cinch)
would it be possible to use this as a frontend and build a "output stage" for it? the output opamps are SGM8262-2 inside KA15, not sure how these react to high impedance loads, does anyone know more here? i just assumed if it can drive low impedance it can definitely drive high impedance...
Sounds like you have taken a path similar that of many of us who have come before you. Always looking for a low-cost, close-to-really-good dac at an affordable price that can be reasonably easily turned into a wonderful gem.
Some of us, most of us on that sort of pursuit, eventually figure out we are on a fool's errand, as painful as that can be to accept. Lots of wasted money trying to find the best low cost dac to start out with.
If you want a really good dac, there are people here who can help assist you to achieving that goal starting with whatever dac chip you want, with whatever you budget is, etc.
However, the reason you probably haven't got any other responses to this thread so far may be that you are starting out in way that is not conducive to attracting responses; you aren't asking the right questions to get help making a dac the right way (not that there is only one right way, but the choices for making a really good dac are not without bounds).
Maybe if you decide what sound and or what measurements you want, and what your budget is, then collectively the more experienced guys here could help you find a good solution.
Other than that, talking about Fiio KA15 without posting a schematic and or hi-res pics is most likely a waste of time. Do you expect the other guys to go do that work for you? If you want some good people happy to provide good help and support to participate here in this thread, then why not help them out by digging up what detailed information you can for what you are interested in doing?
Some of us, most of us on that sort of pursuit, eventually figure out we are on a fool's errand, as painful as that can be to accept. Lots of wasted money trying to find the best low cost dac to start out with.
If you want a really good dac, there are people here who can help assist you to achieving that goal starting with whatever dac chip you want, with whatever you budget is, etc.
However, the reason you probably haven't got any other responses to this thread so far may be that you are starting out in way that is not conducive to attracting responses; you aren't asking the right questions to get help making a dac the right way (not that there is only one right way, but the choices for making a really good dac are not without bounds).
Maybe if you decide what sound and or what measurements you want, and what your budget is, then collectively the more experienced guys here could help you find a good solution.
Other than that, talking about Fiio KA15 without posting a schematic and or hi-res pics is most likely a waste of time. Do you expect the other guys to go do that work for you? If you want some good people happy to provide good help and support to participate here in this thread, then why not help them out by digging up what detailed information you can for what you are interested in doing?
imo that seems to be the real endgame for hifi, since only spending much money might not get you there.. (tho, it might bring you much closer, much quicker)
im very careful with low budget dacs nowdays, its not like i had ultra expensive ones but pretty specific ones i would say...
had a Aune X8 at the time with upgraded opamps (burson V6), it was alright, but in the end i never got happy with ESS dacs
then searched youtube for ADC reviews and came across the black lion audio interface, what intriqued me was that BLA is a "modding company" modding studio interfaces (replacing caps/opamps etc), so i tested it despite the bad measurements and the dac portion actually sounded way better than the aune or any other dac i heared for that matter, much better transient resolution i would say where ESS dacs usually sound "compressed" in transient-details, it just doesnt sound true to life imo and tends to be fatiquing
So... why the BLA sounded so good? well it had an CS chip (and good caps, wima/nichicon, they used even wima as opamp bypass caps, which might explain the bad noise measurements), so i bought now the headphone dongles (headphone dongles because i actually wanted one) to proof my theory if the chip itself might make up the overall sound, imo it does definitely make up part of the sound, output stage still matters and i still slightly prefer the BLA for its more full/bass/mid centered sound signature but hell, the fiio KA15 gets pretty close while measuring a good portion better, so im actually wondering whether its actually more of a chip thing then a specific dac to dac thing (atleast looking at the chip as a key element which makes up part of the overall sound signature)
Also looking recently into chip implementations, i dont believe chip implementations will vary that much from dac to dac if you look at a specific chip, the power supply/input/outputs/output stage might differ alot tho
this question/thread here was really about a specific idea i had/have (specially after hooking the FIIO KA15 up to my speakers, as it sounded surprisingly good), i know some good DIY designs exist around here you can recommend, trying NOS dacs is definitely still on my list
that is really the question.... well i like somewhat neutral with a tendence for more bass/low-mids and smooth-ish highs without losing real details ("real to life sounding transients" for example), tho everyone might interpret this as something else
i always hope i can make sense of measurements and audible perception (for example, the BLA might actually sound so good because of a higher noisefloor hiding low level distortion, as a rude example) tho sometimes its really hard to make sense of things, specially KNOWING how easy humans prefer something that is actually just "worse sounding" like tubes for example
Tho i believe there is "per say" nothing wrong with a good measuring dac (its definitely not the reason why they sound "bad", tho some noise reducing measures/circuits could potentially worsen SQ for whatever reason...)
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since im a somewhat minimalistic fan and having heared the KA15 over speakers, i just wondered how feasible it would be to try to "tune" the good measuring KA15 base (different output opamps/complete different output stage/opamp bypass caps, power bypass caps etc) since chinese pcbs are generally not recommended and something like the fiio is atleast good measuring 🙂
as far i understood the KA15 is a fairly easy implementation of these chips:
USB Chip SPV5048Pro, Dual Cirrus Logic CS43198 DACs, Dual SGM8262 op-amps
the usb chip seems to be unique to the KA15 as a google search just turns the KA15 up, i hope i could either use the opamp output directly or tap into the cs43198
i made some pics of the inside 🙂
Attachments
Okay. I would say this: A good dac board needs at least 4-layers. Any boards with only 2-layers can be disqualified.
Then, for a given dac chip, synchronous operation is usually best, with crystal clocks located very close the dac chip. Besides that time reference, the other thing all dacs need is a good voltage reference (stereo Vref/AVCC).
In addition, freedom from USB bus noise problems can help a lot. It means galvanic isolation to start with.
Proper powering of the dac chip and for any output stage opamps are also important factors.
You might start by reading the thread at: https://www.diyaudio.com/community/threads/general-purpose-dac-clock-board.413001/ ...in order to understand one example of how pretty good synchronous operation can be achieved. If you also need SPDIF/TOSLINK/AES, then an ASRC may also be needed.
Then, for a given dac chip, synchronous operation is usually best, with crystal clocks located very close the dac chip. Besides that time reference, the other thing all dacs need is a good voltage reference (stereo Vref/AVCC).
In addition, freedom from USB bus noise problems can help a lot. It means galvanic isolation to start with.
Proper powering of the dac chip and for any output stage opamps are also important factors.
You might start by reading the thread at: https://www.diyaudio.com/community/threads/general-purpose-dac-clock-board.413001/ ...in order to understand one example of how pretty good synchronous operation can be achieved. If you also need SPDIF/TOSLINK/AES, then an ASRC may also be needed.