CT7302PL

[Markw4]

Its the same sort of thing that can happen when you put too many bypass caps of different values in parallel and they all have some lead inductance. You get a bumpy, wavy impedance curve. You must have a dip or peak at just the right frequency. Something like that.

 

[savan]

It's good that I moved away from a problem that I had no idea what it was about, and made some progress, thats good! Ten days I'm playing with this! I tried several different compensations, changed the frequency... but actually the problem is something else entirely, the gnd, I didn't even think it was a problem, OMG!

 

[Markw4]

Those are the kind of things that make you experienced

 

[savan]

In the meantime got my new pcbs, will contain CT7302PL (to PCM) + ADAU1462 + CT7302PL (to DSD) + CT7601 + BT + FM radio..

PDM microphone trought HDMI, hope ok trought HDMI?

And DSC1 single ended with discrete i/v, multi feedback filter, tone control and single ended to diff.

Picture 2 , XL4015 pre-regulator & Discrete 5V J.D. regulator is the first thing which will be soldered and tested, in case not work good its on separated pcb and easy to replace

 

[JPS64]

Hello Savan,

who´s configuring all the parts using I2C?

JP

 

[savan]

Raspberry pi is control device! Made one static binary and native rpi graphic, graphics can work in overlay mode over operating system graphich in another graphic layer since I have used native graphic libraries, program work in treading mode, sleep all the time until trigered by remote control or by touch screen, so consume 0% cpu, curently touch screen control graphics is not implemented yet but remote control yes, remote control is https://www.audiophonics.fr/en/infr...evo-sabre-raspdac-mini-lcd-38khz-p-15309.html , controling with it volume level, inputs, bass and treble, whole aplifier is not DDPD but DSC2 diferential version, audio transformators is replaced with OPA1637 as I/V than diff to se converted with INA849 DC servo controled with THP210, than added multi feedback OPA1656 and tone coontrol and se to diff OPA1637, power amplifier is two UCD180HxR, and the rest fm radio, bluetooth, 4 optic inputs, Amanero input, analog input WM8782, RPI4... etc. THe hearth of thing is CT7302 and DSC2, Thats my main device. Thats pure DSD as like DDPD is also pur DSD. DDPD still better sounding, it promising with DSP, didn't tried but as you can see pcb is made and one bug on them (ISOUSB111 instead of ISOUSB2111) make me that I need to get new pcb, it will be in month : ( CT7601 didn't tried too, plan is to replace Amanero, and since CT7302 is great device I'm believing CT7601 will work as good as CT7302. If anybody look into CT7601 datasheet thats a ton of registers, an very configurable IC, unbelievable lot of registers and options, hmm it will be a lot of work until it get configured, my hope not that complicated, I will be happy to get first sound using default configuration and later to play with the rest. On Comtrue site there is only brief DS for CT7601 and if you need to see registers you need to ask them for full documentation, maybe only available if you buy IC. Also I would be happy to replace Amanero, CT7601 use small pcb space and hope sound close to Amanero even better, let see : )

Post 124 picture 1 is single ended version of DSC dac with discrete I/V and MFB and tone control the same as in my device, I just developed that pcb and realy want to hear how it will sound, a lot of things to try and less time for development, even my main device not yet finished fully : (

 

[savan]

If DSC single ended with mfb and tone control sound ok I will post project in original thread hope it get interesting for somebody -> https://www.diyaudio.com/community/threads/signalyst-dsc1.254935/ , my focus is on DDPD and frontend. And I'm not happy with opamps in my device, it colorate sound, audio transformers sounded better than INA849 and things! DDPD is the right way definitelly, dynamic and lifelike sound uncomparable to anything.

 

[savan]

Just think how many stages is in an analog circuit, e.g. from USB IN to the speakers, we can briefly list them: Amanero -> digital to analog converter -> I/V -> AC or DC coupling -> filter or miltifilter -> buffer -> AC coupled input on e.g. UCD180HxR so capacitor -> another buffer -> comparator and things -> PWM (call them analog converted back to digital) -> LC filter -> speakers, a lot! Now let briefly look into DDPD schematic how simple it is and how short audio chain is and without any digital to analog conversion, without opamps, without opamp buffers, without AC coupling capacitors... digital to analog conversion is done at LC + spekers! We call them DDPD, direct digital power dac since its in the same time power amplifier and dac. Just think about all this!