Hmmm…Steve confirmed above that an I2S feeded dac has volume control over the app, so the I2S data stream is “manipulated” by the Up2stream board and the analog output if the dac is scaled e.g. 0…2V RMS, depending by the volume setting of the device. So there is no need to control the volume at the amp.
So you are right, with a JAB5 there would be double volume possible. When i am right, it should also be possible to run the JAB5 with I2S input and fixed volume setting (e.g.70%) and control the volume still over the Up2Stream digital I2S volume control.
The plan is to regulate the volume by the app/api/uart only without the need for a separate µC.
This should be possible with the use of a fixed gain amplifier without extra volume control, with direct I2S input (“software manipulated” from the Up2Stream module) or with an analog amplifier with an I2S DAC before.
So it is still unclear for me why in some other threads a loose of volume control in conjunction with an I2S feeded amp is observed. The JAB5 gets the same “manipulated” I2S stream as an external DAC and contains volume information.
Yes, the JAB5 can be used with a fixed volume setting. But it’s also manipulating the digital signal, because the volume is controlled by the DSP. In this case the digital information is recalculated twice.
I don’t know any »fixed gain amplifier with I2S input«. If you can send me product suggestions, I’m interested.
In my other project – DAC board packed on a Raspberry Pi and 3e Audio amplifier and Volumio – I know there exist two kind of volume controls on DAC boards. One recalculates the I2S signal – via software –, and the other ones have an array of resistors behind the DAC and manipulates the analog signal – they are called hardware controlled.
Dear j.eeken1,
can you confirm the connection between Mini/Pro v3 to the Wondom ADAU1701 board is tested and working fine?
On paper it doesn’t seem okay. Here’s why:
Take a look at the manual for the Mini/Pro v3
“PH2.0-7P: SPDIF, MCLK, IIS_DATA, BCLK, LRCK, GND,
VCC_3V3:
This is the digital audio output extension. For the IIS, BCLK is
2.8MHz, the LRCK is 44.1KHz, the MCLK is 11.288MHz, the
DOUT following the standard IIS data format and have 16 bits
depth. The system is running in master mode, you should make sure the IIS port of connected device is running in slave mode.”
This means that the Mini/Pro is outputting the master clock, and the ADAU1701 should be set to slave.
In order to feed the MCLK signal from Mini/Pro to the ADAU1701 we should follow the instructions, given by Wondom - desolder the oscillator on the ADAU and feed the MCLK to the SMD pad, marked Y1.
@ j.eeken1
Looking at your earlier posts, other idea comes to my mind.
On the ACPWorkbench screenshots you provided, I see that maybe it would be possible to set the up2stream Mini/Pro as a slave and accept master directly from the MCLK pin on the ADAU1701 pcb. The MCLK of the Wondom pcb is 12.288Mhz, so in theory this is also a possible solution.
Unfortunately I don’t have neither the pcb, nor the software to check this myself.
I would really appreciate if you check this and confirm it is possible.
I am researching to build a setup, based on the Mini V3 and ADAU1701. The only draw-back which stops me from purchasing the modules is this little uncertainty. I don’t want to desolder any parts of the nice prefabricated boards, make them work.
I can confirm you that it is working properly. I’ve done it severel times but, I always use other dacs to output the sound and not tested with the internal dac of the dsp board itself. By the way don’t try it with the JAB3 boards. Don’t know why but they simply don’t work. Even with desoldering the oscillator.
I will look onto that with the internal dacs this weekend if you are not sure.
About the mini/pro in slave mode; I didn’t try that,because I didn’t need to. I will look into that too.
Thanks for the quick response, Jordy!
Looking forward to hear the result of your tests!
Don’t think it matters whether or not you are using an external DAC or the adau1701 DACS
As for the JAB3, I’m not planning to use it, I will use just the dsp kernel board and feed the signal to 3 channel class AB amp, for a 2.1 system (not a fan of class D). Just want to add some modern features like Bluetooth and streaming, and the DSP will handle the sub/high pass crossovers.
Jordy,
thanks for the presentation.
The Arylic module sends 44.1kHz MCLK (it is always working as a master)
The Wondom board:
-The MCLK pin (pin20 on expansion port J4) is connected to MCLKI (pin 32 of the microcontroller)
-If the oscillator is not removed, the dsp sampling rate is still 48kHz (256*48kHz=12.288Mhz)
I assume there’s no effect by connecting the two MCLK pings (arylic to wondom)
I also assume that the I2S communication is somehow still working, but the output (arylic) is not fully synchronized to the input (wondom) since there’s no unified MCLK for the entire “system”. This should normally cause some jitter (even though it may not be audible).
I would suggest you disconnect the MCLK and try without it. I am positive it would work without that bridge.
p.s. I’m still curious about the settings in APCworkbench software.
Stanislav,
I tried the Pro in save mode and it doesn’t work. You may ask Arylic if it is a firmware issue.
I was curious about the timing when removing the oscillator and must say that it is audible. Thanks for that and I’m still learning.
Most sources provide a master and for the 20 $/€ of the dsp it doesn’t cause much of a pain to remove clock.
For the price, this is a real good device and never had an problem. But, stay away from the other wondom products. They are faulty.
If you need any help on programming it. You can PM me.
Jordy,
I’m also still learning. In the conversation the truth is born…
Thank you for trying the adjustments from the software. Saved me 20€ for it.
About the MCLK, you decided to desolder the crystal? And the sound improved?
By the way, now your dsp board is running at 44.1kHz sampling rate. The filter coefficients are dependent on this clock, so they are slightly changed as well. You may want to adjust it.
I am happy that we were useful to each other and hopefully to the rest of the enthusiasts.
I’m going to order up2stream mini and the adau1701 board from wondom.
About the other wondom products, thanks for the advice, I’m really not into class D amps.
Hi thank you creating this Tutorial.
I was thinking of retrofitting the Second on into an old amp an therefore making it a little more up to date. I bought all the components and tried to recreate it but was only party successful.
I was able to connect the Up2Stream Mini to the DSP via I2S and get the Signal out of the onboard ADC an into the AMP (ADC0 and ADC1).
Trying to use the better PCM5102 is where it stops working. Following your wiring and the Hardware config it wont work.
Maybe you are able to tell me what ive done wrong! Thanks upfront
I’m going to look at it on sunday or monday. Not much time right now. In the meantime you can try to connect the pcm5102 board directly to the acylic board if it is broken or not. Second you can try to change the dsp to Slave mode.
I plan to use the I2S OUT of the Up2Stream HD DAC to drive a Dayton Audio KABD-4100 (in SLAVE mode to disable BT); the KABD-4100 is, I believe, identical to the Wondom, so this article is exactly what I needed! Thanks! I’ll report back with issues/results/photos…
