Hmm ... As noted earlier, when I connected the USB-I2S adapter's I2S/mck/GND via pcb pads ... see the labelled via pads on the Chinese 1305 board here ...
https://www.diyaudio.com/community/...-3-5-cd-player-schematics.395185/post-7266145
.... I was ahead (downstream) of the CS8412 (further, the CS8412 was un-powered and may have further been isolated by those white Omrom relays -- see photo in post 23). As I speculated, the Chinese designer may have put in those I2S/mck/GND via pcb pads for the purpose of adding in an Amanero (or other USB-I2S adapter).
But that didn't work because of the 256fs I2S limits with the 1305.
I am going to experiment wit the Vanguard 11.289 osc. -- as the syscklc (mck) -- later tonight.
I suppose one good thing about the digital audio side of electronics is that a limited understanding won't kill you. Unlike a 211 amp.
Yep ... giving where you're From, I can see your point ( " . ") .
The 11.289 oscillator SYSCLK injection experiment did yield audio, but it was distorted.
Given the modular (Molex) layout I deliberately "designed" for in the 1305 kit, the whole experiment took less than 5 min.
It would be cool to hack the XMOS U208 somehow to output 256fs MCK.
Distortion is to expected. The canned module is in one clock domain and the audio in another hence no sync.
On the Amanero website is a tool for making changes to the board. There is a 256Fs option. It may work with your board.
On the Amanero website is a tool for making changes to the board. There is a 256Fs option. It may work with your board.
Anyone know what the TOTAL current draw of a 1305T may be?
The datasheet values add to:
Typical: 42mA
Max: 47mA
But when I measure with a DMM, I note 68-70mA (music playing).
Curiously, if I disconnect the USB-I2S (Amanero), current draw drops to 13mA.
The op-amp-based regulator runs a bit warm but total ripple is a clean 1.5-2.2mV(ac) when music is playing.
So, what is in the TDA1305 setup that's drawing a whopping 28mA of "extra" current when USB is connected?
Could it be active I2S and mclk coming from the Amanero (via ASRC)?
The datasheet values add to:
Typical: 42mA
Max: 47mA
But when I measure with a DMM, I note 68-70mA (music playing).
Curiously, if I disconnect the USB-I2S (Amanero), current draw drops to 13mA.
The op-amp-based regulator runs a bit warm but total ripple is a clean 1.5-2.2mV(ac) when music is playing.
So, what is in the TDA1305 setup that's drawing a whopping 28mA of "extra" current when USB is connected?
Could it be active I2S and mclk coming from the Amanero (via ASRC)?