Develoment version above in my hope get assembled into enclosure next day hope tested too, today I have colected & corrected all bugs, next pcbs will be ready for production! Next pcb will look like as on picture, green color pcb. Next step for me is start working on frontend. It will be in seccond blue enclosure, will contain 4 optic imputs (if allow space), one usb input and bluetooth, and five SMA connectors. My hope there will be enought space for all that, it will be challenge for me : ) Pcm2dsd, dsd2pcm, based on CT7302PL. Usb option will be probably Amanero option but without fw since I have no plan to buy licence and I want things legal. You will need to upload fw. Amenero is sucesfully made in my other projects by using official public schematic available on their site. Option two for usb is CT7601, curenly I have ic but its never tried and I don't know when I will try it, when I get time for it, I have other projects which contain CT usb but I need to solder them and try, if it work than I will replace Amanero option with CT. The first version will be with Amanero without fw. I will start frontend development from the back side, to see how many connectors can fit, based on that I will design the frontend. This Mini DDPD simply deserve an minmal frontend. Thats it : )
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Two hours debuging circuit to indentify why ddpd can't play any sound, finaly after two hours of hard work I remember that I have cut some part of thepcb, small side between front pcb and main pcb around ir led, found that I have cut one wire in sendwitch layer, omg, put some small wire to replace broken pcb wire and finaly it work, all work as I expected. : ) The only but I have found is in relation to firmware, volume level is not remembered, I will fix all that so that production pcbs have bug free! Let me know how many of you want DDPD Mini?
This is how I made interconnect cable between ddpd and amanero
This is how I made interconnect cable between ddpd and amanero
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Ok, price you know? The one from OP was advertised as 250 eur, now you have the same thing but revised pcb and now gratis all in blue alu enclosure with oled, buttons, ir led, price is the same! If you need IR control this one is compatible https://www.audiophonics.fr/en/infr...evo-sabre-raspdac-mini-lcd-38khz-p-15309.html . You will need to buy an DC power supply, 12V 3A, will be very good. Please let me know! I will need to contact my post office and get info about international shipping, I never sent anything internationaly and must ask first which options I have, and I will let you know.
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I have Cosmos adc but have no idea how to measure ddpd since dsd-in is reguired, but when frontend get finished it will be easy to create digital loop inside Rew software trought Amanero IN and pcm2dsd OUT. The main problem is the excitation signal that is in Rew in pcm form, but I need dsd since ddpd is dsd power dac. If you have idea let me know
Sent PM also.
I'll ask here for the benefit of everyone - is DSD 64 max recommended rate? Are there any constraints for faster rates?
-Raja
I'll ask here for the benefit of everyone - is DSD 64 max recommended rate? Are there any constraints for faster rates?
-Raja
I have tested up to dsd256 with no diference between dsd64 and dsd256. in my opinion, it might be comfirmed by measuremens which curently I can't complete because lack of needed digital fontend. Full bridge here is very fast, propagation delay is maximum 20ns, it is capable of much higher rates e.g. dsd512. I recommend dsd4, dsd64 is almost 3MHz, in comparation to PWM modulation 100KHz which is inside most of the class D. Here is no limit since this do not have any opamp, any comparator...etc, the only limit is propagation delay inside full bridge and the rest of propagation delay inside dsd-in. There is small dead time around 10ns formed by rcd. Full bridge contain 32 half bridges per channel, it form 32x average current which is around 2x5Wats in total.
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Multitone Analyzer has DSD signals also. Either DoP or native DSD.
https://distortaudio.org/multitone.html
Thanks for info! The problem might be setting/knowing right levels setup, I will try in next few days, hope I setup all right. : )
This is preliminary tests, I don't know if setup is right! Setup is done by using an AUX filter with builtin 8ohm dummy load. Amanero is input device and Cosmos adc is output device. All config as like on picture. Schematic of the aux filter with dummy load is in attachment. Attenuation is around 10x , L values inside schematic is 1mH . Cosmos switch is 4.5V. DDPD volume is set to max value = 5V. Vrms in multitone I type is wrong? Might I correct sommething in setup?
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simulation result of the attenuator picture 4, I see attenuation is 50/2.15=23.25, right now I am unable to figure out about right setup values inside multitone and allso hw switch of the Cosmos need to be set to the right possition. Than measurements would be probably correct, any help is welcome! : )
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simulation result of the attenuator picture 4, I see attenuation is 50/2.15=23.25, right now I am unable to figure out about right setup values inside multitone and allso hw switch of the Cosmos need to be set to the right possition. Than measurements would be probably correct, any help is welcome! : )
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Were you supposed to use DSD signals? If so then select appropriate DSD mode from settings panel.
Yes thanks, I want dsd64, did I set all right? Better result will be expected after right interconnect cabling, curently Amanero is connected trought half coaxial, some hacks in cable is done, but results will be better with full coaxial connection, right now small amount of the cable hack is act as an antena I know.
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This is 1bit dsd, Asio driver is replaced right now with FlexAsio_v1.9, done it since Cosmos need FlexAsio? DSD mode I set to none since only two options is available, none and dop, dop is not suitable for ddpd, need pure 1bit dsd. I have no idea how to do right setup right now : ) I will try to switch to Asio.