Jean Paul,
Based on the following sentence:
"The AK4495S/95 has full differential SCF outputs, removing the need for AC coupling"
do you think a direct balanced connection from the dac to the MA12070P is save, since
in the MA12070P Datasheet it Staates:
"For the DC protection circuit to trigger, the DC value of an output pin must be staying above 0.63*PVDD or below
0.37*PVDD for more than 700ms" Since I love the sound of the AK44?? Dacs I am really tempted to give it a try.
Not with my Compression Drivers though.
Based on the following sentence:
"The AK4495S/95 has full differential SCF outputs, removing the need for AC coupling"
do you think a direct balanced connection from the dac to the MA12070P is save, since
in the MA12070P Datasheet it Staates:
"For the DC protection circuit to trigger, the DC value of an output pin must be staying above 0.63*PVDD or below
0.37*PVDD for more than 700ms" Since I love the sound of the AK44?? Dacs I am really tempted to give it a try.
Not with my Compression Drivers though.
Interesting! Thanks for the update and yes, would definitely be helpful to know the NVS params and configs you used esp if these haven't made it into the standard instructions yet (or the Squeezebox forum thread, I was chasing it down a while ago).
I really like Squeezelite on ESP32 for its quick start up and easy configuration. With the MA12070P it should make a nice efficient portable Squeezebox Radio alternative. But at the moment I'm trying to make a wired desktop amp with multiple inputs, not just for LMS. So the Orange Pi SBC makes sense as a controller. It even has a OTG USB which can be configured as a USB audio interface...
Nice - simple and neat! May I ask where you got your MA12070P board from and if the output is reasonably noise/hiss free at low volumes?
The Lusya/Shenzen Pillor board cost £30, the most I've spent on a bare board chip amp. There are cheaper MA12070P boards available now but it's a bit disappointing if this board or chip can't do better than the old Tripath TA2020 board I've got connected to a crummy PCM2704 USB stick in an Altoids tin as my current desktop amp!
The board is an Infineon REFAUDIODMA12070PTOBO1. A bit pricy but a fun project once I got it up and running. It's quiet, but I'll hook it up to my Klipsch Heresy's for a better test. The nice thing about this board is that the /ENA and /MUTE pins are hard wired. I had trouble getting the Murus PI Zero Hat to work with the ESP32, and I think it was because I couldn't get these pins set correctly. Ended up sticking with Picoreplayer to get that to work.
The NVS parameters I use...
autoexec1 squeezelite -o I2S -b 500:2000 -d all=info -C 30 -W -n squeezelite-XXXXX -R -r "88200-88200"
dac_config model=i2s,bck=33,ws=25,do=32,sda=14,scl=13,i2c=32
dac_controlset { "init": [ {"reg":53,"val":136}, {"reg":54,"val":81} , {"reg":64,"val":36}, {"reg":45,"val":52}, {"reg":45,"val":48}] }
For the most part I copied the init code from the Merus lixux driver for the MA12070P. The main change was to allow for a 32 bit word length (16 bits left and 16 bits right). I set the sample rate to a fixed 88.2K, but 96K will work as well. Again, I'm not using MCLK, but sending BCLK (SCLK) to both clock pins on the MA12070P.
If all goes well, you should get this via telnet...
I (3052) I2S: APLL: Req RATE: 88200, real rate: 88199.977, BITS: 16, CLKM: 1, BCK_M: 8, MCLK: 22579194.000, SCLK: 2822399.250000, diva: 1, divb: 0
[00:00:01.349361] output_init_i2s:319 i2s DAC using I2S bck:33, ws:25, do:32, mute:-1:0 (res:0)
[00:00:01.349730] output_init_i2s:339 Initializing I2S mode normal with rate: 88200, bits per sample: 16, buffer frames: 512, number of buffers: 12
The SCLK value generated is a valid value for an 88.2K sample size, and can be used on the CLK pin of the MA12070P.
Mike
Attachments
Ah thanks a lot for posting that, I'll give the ESP32 a try in a while. At least you know the reference board should be a good implementation and that reminded me to check out its data sheet circuit diagram. It looks like enable and mute pins are simply wired down and up with jumpers, I'm a bit surprised there isn't a pop on start up - but I guess the amp is disabled when there isn't a clock! The Shenzen board has an RC delay on these lines but that maybe that's another hang up from sharing the same layout as with the analogue input version. I noticed that the chip ignores I2C commands when enable is high so there's a potential race condition with the driver if it doesn't control enable and/or wait.
There is a faint click...definitely not a pop. I have been listening to it on my Heresy's and I can't detect any noise/hiss.
Maybe you mix up items?! It says "output pin" of the MA12070 but I think you mean to connect a DAC to the input pins. Please note that these are at 2.5V DC (both of course). I read in this thread that it was slightly DC but 2.5V is not slightly. That is simply DC
Assumption is that even if it works Ok it will cause severe power on/off plops. As I had doubts I chose the transformers. I also want a real volume control and not the DAC controlling volume.
Even less:
€ 23,23 34%OFF | 2X80W MA12070P + ESP32 Raspberry Pi Null 3 4B befestigen IIS I2S eingang hifi power verstärker bord
https://a.aliexpress.com/_mrSccU6
€ 23,23 34%OFF | 2X80W MA12070P + ESP32 Raspberry Pi Null 3 4B befestigen IIS I2S eingang hifi power verstärker bord
https://a.aliexpress.com/_mrSccU6
Unbelievable
€ 22,76 26%OFF | 2*80W Infineon MA12070 Digitale Audio Power Amp Lautsprecher 20W ~ 200W HiFi Stereo Verstärker Klasse D Aux DC15-19V
https://a.aliexpress.com/_vWpxny
€ 22,76 26%OFF | 2*80W Infineon MA12070 Digitale Audio Power Amp Lautsprecher 20W ~ 200W HiFi Stereo Verstärker Klasse D Aux DC15-19V
https://a.aliexpress.com/_vWpxny
Richard,
Sorry for the late reply, was travelling and just got back. Happy to share the schematics and layout. I drew everything on EasyEda and have attached a backup file which you will need EasyEda to open again. There is readme file with some cryptic instructions on how to do it. I did this quickly and I'm sure there is a better way of doing this. Let me know if you have issues with opening the file.
I've also got a few spare PCB's that I'm happy to post out at no cost in exchange for a contribution to DIY Audio. One PCB is good for a stereo analog or digital, although I've only assembled it for digital.
Patrick
Alright gus here are my initial impressions.
Ayima 08
Analog section skipped. Couppled balanced over 4 Siemens MKV caps. Dac at the moment AK4490.
Very spacious 3D like. Better than TDA3255.
Highs also better than TDA3255.
Very natural dare I say analog like sound.
Only for high efficiency speakers when used as I did with neither an output stage on the dac site nor on the amp site.
That's it for now.
Klaus
Ayima 08
Analog section skipped. Couppled balanced over 4 Siemens MKV caps. Dac at the moment AK4490.
Very spacious 3D like. Better than TDA3255.
Highs also better than TDA3255.
Very natural dare I say analog like sound.
Only for high efficiency speakers when used as I did with neither an output stage on the dac site nor on the amp site.
That's it for now.
Klaus
Shiu???? something with analog stage skipped. Beefy linear supply with Siemens Sikorel caps.
Dac as mentioned.
Windows Server 2016 fully loaded into RAM.
Dante Diy with Monisms modules.
No rephase no drc.
Speakers at the moment of evaluation Acron 500b, 2x Ripol with 12" Speakers each.
Dac as mentioned.
Windows Server 2016 fully loaded into RAM.
Dante Diy with Monisms modules.
No rephase no drc.
Speakers at the moment of evaluation Acron 500b, 2x Ripol with 12" Speakers each.
Attachments
After I tapped the caps, I put on instand acrylate glue with baking Soda for tension relieve. I left the active stage untouched because I did not know if the signal detection is managed by separate Pins.
Attachments
Sound impression was based on only one song after which we had no time to further evaluate. The unit never played a single song in stock form. Power supply was the one that came with the unit. There is certainly potential for further mods.
After I switched to Dante I never used a volume Pot. That might change when I hook up my Compression Drivers. I have yet to hear a volume pod that is as transparent as a 32bit playback mildly taxed (Drc, Crossover, phase correction) Audio PC system.
Klaus
After I switched to Dante I never used a volume Pot. That might change when I hook up my Compression Drivers. I have yet to hear a volume pod that is as transparent as a 32bit playback mildly taxed (Drc, Crossover, phase correction) Audio PC system.
Klaus
