it's weird that c-media or savitech don't reply at your mails.
i work for a very small company (2 people) and they always reply at me.
i don't even buy their chip directy to them, i order them on aliexpress or taobao.
c-media support reply everytime 1 day later due to time difference.
they gave me full datasheet and i work with CM6631A and CM6632A, for CM6631A they gave me a custom firmware tool maker. and for CM6632A they don't offer one, but they can custom the firmware for you for free.
for savitech i had to sign a NDA and they gave me all datasheet of all their usb solutions and a custom firmware tool.
i work with SA9227, it's smaller and more powerful than CM6632A.
they also reply 1 day later due to time difference.
i work for a very small company (2 people) and they always reply at me.
i don't even buy their chip directy to them, i order them on aliexpress or taobao.
c-media support reply everytime 1 day later due to time difference.
they gave me full datasheet and i work with CM6631A and CM6632A, for CM6631A they gave me a custom firmware tool maker. and for CM6632A they don't offer one, but they can custom the firmware for you for free.
for savitech i had to sign a NDA and they gave me all datasheet of all their usb solutions and a custom firmware tool.
i work with SA9227, it's smaller and more powerful than CM6632A.
they also reply 1 day later due to time difference.
Cmedia gave me their distributor contact in Shenzhen and don't support me directly. I just complain about the distributor to Cmedia and next the distributor becomes more responsible. It is a common problem in china because of education level is extremely low it is a hard task to find right local FAE. For example, I got two emails the same day from that distributor regarding CM6642 initial firmware, one said "CM6642 need to be reprogrammed to obtain SPDIF", another email said CM6642 don't need to reprogram and a brand new chip has SPDIF On by default. I email to Cmedia with a rhetorical question "what a f.. is that?", and the same day their distributor sent me the 6642 USB programming tool. Sometimes I felt the distributor doesn't interested to give me app info at all. And I spent a few months just to get trivial info and primitive prog-tool.
test1, where you from?
In my case, I understand that Cmedia has a lot of stupid chinese "customers" with the same single request "pls make for me design, and I'll buy your chips". So, a tiny company was overloaded, and found some local chinese to provide "comprehensive support". I know some ukranian/russian engineers who also got direct Cmedia support, just because their countries have no Cmedia's FAE.
Regarding SVS, I sent them email with request of any awailable app data for USB/I2S ICs but they didn't reply. Next I go taobao to check availability of these ICs and I found it way tooooo expensive. BTW, as I understand, taobao shops provide all app-info right away, if you buy their stuff.
In my case, I understand that Cmedia has a lot of stupid chinese "customers" with the same single request "pls make for me design, and I'll buy your chips". So, a tiny company was overloaded, and found some local chinese to provide "comprehensive support". I know some ukranian/russian engineers who also got direct Cmedia support, just because their countries have no Cmedia's FAE.
Regarding SVS, I sent them email with request of any awailable app data for USB/I2S ICs but they didn't reply. Next I go taobao to check availability of these ICs and I found it way tooooo expensive. BTW, as I understand, taobao shops provide all app-info right away, if you buy their stuff.
The SAM D21 and PIC32MX270F256D both come in fairly compact yet hand solderable packages and have i2s modules that are probably capable of USB audio. I believe the dragonfly USB dacs use the PIC but I don't know of any projects that use the SAM as a USB audio bridge. I am inclined to try the SAM with the arduino ide but I don't know if the two are suitable for the task.
Some of the Teensyduino boards are capable of i2s over USB and there is even a gui tool that will help configure it for you.
Teensy Audio Library, high quality sound processing in Arduino sketches on Teensy 3.1
Some of the Teensyduino boards are capable of i2s over USB and there is even a gui tool that will help configure it for you.
Teensy Audio Library, high quality sound processing in Arduino sketches on Teensy 3.1
nofun, you are right. I also saw pic32mx as USB/I2S here: https://www.cyrusaudio.com/wp-content/uploads/2017/11/Clean_Top_view_soundKey-2000x1335.jpg It is compact and super-cheap(if not to say extremely cheap, 1$ pic32, $1 PCM5102, $0.5 TPA6130A2RTJR, and even 3.5mm jack isn't gold-plated!). However, it is only 24/96 and probably has awful jitter because the device specs are way worse than Ti's DAC used there.
PS: Oops, dragonfly red looks quite similar Review and Measurements of DACPort HD and Dragonfly Red | Audio Science Review (ASR) Forum
So, perhaps PIC32 without any clock makes a really bad job. BTW, I measured with AP2702 my old $300 chinese android Nubia Z11 with AK4376 3.5mm output with 1kHz 16/44.1THD+N .0015%(16bit theoretical limit!) SNR -118dbA, power the same as dragonfly/soundkey and similar. I really believe that any old iPhone with 3.5mm or Apple's USB/3.5 adaptor will outperform these DACs in an effortless manner.
PS: Oops, dragonfly red looks quite similar Review and Measurements of DACPort HD and Dragonfly Red | Audio Science Review (ASR) Forum
So, perhaps PIC32 without any clock makes a really bad job. BTW, I measured with AP2702 my old $300 chinese android Nubia Z11 with AK4376 3.5mm output with 1kHz 16/44.1THD+N .0015%(16bit theoretical limit!) SNR -118dbA, power the same as dragonfly/soundkey and similar. I really believe that any old iPhone with 3.5mm or Apple's USB/3.5 adaptor will outperform these DACs in an effortless manner.
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I'm from France.
I can share some information if you need.
I've successfully make CM6631A/CM6632A (CMEDIA), SA9227 (Savitech) and TE8802L (Tenor) work with my own PCB.. and so far SA9227 seems the best.
By the way ,i've just seen there is a new IC SA9228 from Savitech on their roadmap..
test1, as I said I have Cmedia contact but only thru their distributor in SHZ. SA9227 is too expensive on taobao, even XU208 XMOS is cheaper, so I see no reason to try SA9227 yet. TE8802L no interest.
You know what, try to ask Cmedia about CM6645 IC, SHZ distributor says this IC isn't supported, and recommend me to use CM6642 instead(and I do). I suspect Cmedia got bad jitter performance with CM6645 because the IC has no any clock input, only USB(the same as PIC32). I'm fine with CM6642 but I have to use DAC with SPDIF builtin(ES9038Q2M).
You know what, try to ask Cmedia about CM6645 IC, SHZ distributor says this IC isn't supported, and recommend me to use CM6642 instead(and I do). I suspect Cmedia got bad jitter performance with CM6645 because the IC has no any clock input, only USB(the same as PIC32). I'm fine with CM6642 but I have to use DAC with SPDIF builtin(ES9038Q2M).
IVX it looks like the PIC might only be capable of generating its mclk by pll. The samd21 can operate as i2s slave so jitter could be much better. UAC1 should be possible with the sam but i doubt uac2 is. If there was some functional code around i think the pic or sam would make a fun diy platform despite the limited performance. I'll give the samd21 a try but I'm not expecting anything soon if ever.
That soundkey dac looks impressively cheap, from its measurements the tpa6130 and ceramic coupling caps at its inputs might limit the performance more than the pic. It also looks like the tps either shares the ldo with the dac or it just runs straight off the usb supply. I don't see any chokes either.
That soundkey dac looks impressively cheap, from its measurements the tpa6130 and ceramic coupling caps at its inputs might limit the performance more than the pic. It also looks like the tps either shares the ldo with the dac or it just runs straight off the usb supply. I don't see any chokes either.
To make BOM cheap and keep performance great is the kind of art but make cheap junk, not a big deal )) When I chose 2.5mm jack and saw gold-plated one for 5 cents, I didn't check how much nickel-plated one - no reason. How many units need to sell to get a serious profit from 5 vs 4 cents BOM difference? I think it is ridiculous, if not to say shameful economy ))
Attachments
easy but I don't believe if that junk is worth trying, you better take a look at CT7601
https://drive.google.com/file/d/1LpnCj_IX4EBwMMho08h22JpMvf_jvFRf/view?usp=sharing
https://drive.google.com/file/d/1LpnCj_IX4EBwMMho08h22JpMvf_jvFRf/view?usp=sharing
HI
I would like talk with you, are you have a red social where i could send you a msg?. I tried it by this way (diyAudio) but I didnt find a way to send msg.
I want to ask you about an proyect that i thinking of an usb dac of minimal 8 ch and adc of 4 ch, i want this to make a self-made home system audio for me, but i only found an expensive chip to bridge usb class audio compilant to i2s codification (XMOS XU208), and then an pcm3168A codec with i2s in/out comunication. Have you know about an alternative to this, or how we could implemet ethernet instead usb interface?
Sorry of my so-so english
I would like talk with you, are you have a red social where i could send you a msg?. I tried it by this way (diyAudio) but I didnt find a way to send msg.
I want to ask you about an proyect that i thinking of an usb dac of minimal 8 ch and adc of 4 ch, i want this to make a self-made home system audio for me, but i only found an expensive chip to bridge usb class audio compilant to i2s codification (XMOS XU208), and then an pcm3168A codec with i2s in/out comunication. Have you know about an alternative to this, or how we could implemet ethernet instead usb interface?
Sorry of my so-so english