Everything looks good. Almost as my setup but I havent implemented in a case yet 🙂
What is this for?
You can tap rs232 signals direct off the rpi2 to the dam. No need for USB-serial adapter. Or do you mean something else?
BTW: I like archphile distro (or picoreplayer with LMS) better that volumio/runeaudio/moodeaudio.
What is this for?
You can tap rs232 signals direct off the rpi2 to the dam. No need for USB-serial adapter. Or do you mean something else?
BTW: I like archphile distro (or picoreplayer with LMS) better that volumio/runeaudio/moodeaudio.
I decided to go with Volumio but have tried archphile and others as well. I like the web-based player option, so that everyone can use its own mobile w/o any set-up to control the full music library. Ease of use was important, since I wanted to come home, press play and everthing is working (auto-on at the mackies and automatic server start of the Freenas box).
How can you control the rs232 via RPi2? I have seen the Arduino set-up. Right now, I used a USB-serial converted and integrated it into the existing 2 USB slots of the case at the right side (the other USB for the Xmos USB Input). Since I do not want to change the filters each day it should be fine but would be interested in the RPi2 set-up.
Since the Xmos and the RPi2 is using the same I2S pins, have you seen a good way to switch beweetn the inputs? Also can the RPi2 make the insput selection?
How can you control the rs232 via RPi2? I have seen the Arduino set-up. Right now, I used a USB-serial converted and integrated it into the existing 2 USB slots of the case at the right side (the other USB for the Xmos USB Input). Since I do not want to change the filters each day it should be fine but would be interested in the RPi2 set-up.
Since the Xmos and the RPi2 is using the same I2S pins, have you seen a good way to switch beweetn the inputs? Also can the RPi2 make the insput selection?
RPi uart is GPIO pin 8,10
Be sure to turn of console : UART Pins – Raspberry Pi Projects
Have a look also at the python scripts to control DAM1021..
https://github.com/fortaa/dam1021
https://pypi.python.org/pypi/Mopidy-dam1021/0.4
Odroid C2 looks promising for USB and i2s as RPi 2 will have 192K limit (onboard oscilator)
Squeezelite v1.8.4-720 compiled (aarch64) with DSD works good for DSD128/DOP (352,8/384K)
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Hi Soren,
Could you please share schematics around 74LVC595A shift registers. I have board r2.
Could you please share schematics around 74LVC595A shift registers. I have board r2.
Could anybody enlighten me if dam 1021 does upsumpling. And if yes, would it be possible to disable this function. This might have been discussed already but I could not find the thread, if any.
Too much HF from the RPi to reach all the way would be my guess. Only a simplistic, but not too simplistic solution, would be the best.
//
Very nice construction and a great idea to use these nice ITX cases. Where did you buy them? Would be perfect to buy them in Germany.
Best Regards
Philipp
Attachments
For the higher end files, I have included a XMOS DSD DXD 384kHz high-quality USB to I2S/DSD PCB, that can be connected through an adapter to the USB socket in the case, so you can plug in an external USB source and play your DSD files (not test with DSD yet but with 192khz flacs.
The DAM does oversampling in 2 "passes". There is a way to bypass one of the "passes". If you search this thread you will find a lot of information on how this can be done.
Hi All!
This is very interesting for me. Does the DAM do upsampling or just oversampling. I thought that oversampling is done by the implemented filters.
Out of my experience upsampling is a completely useless thing as it causes information losses and in any case sounded inferior to non- upsampling condition- to my ears. I've tested that a thousand times.
Every file should be handled in it's natural condition. 16bit 44.1khz should be converted as 16bit 44.1khz and so on.
What I would be very interested in is: Total NOS without upsampling. Could this easily be done with the DAM?
This is very interesting for me. Does the DAM do upsampling or just oversampling. I thought that oversampling is done by the implemented filters.
Out of my experience upsampling is a completely useless thing as it causes information losses and in any case sounded inferior to non- upsampling condition- to my ears. I've tested that a thousand times.
Every file should be handled in it's natural condition. 16bit 44.1khz should be converted as 16bit 44.1khz and so on.
What I would be very interested in is: Total NOS without upsampling. Could this easily be done with the DAM?
This has been discussed (at length I believe..) about a year ago (maybe more) in this thread. The conclusion was that for proper operation the actual resistor ladder must be driven by an oversampled signal.
Thanx Dimdim!
Does that mean, that the ladder dac principle generally needs an upsampled digital signal for proper operation?
Does that mean, that the ladder dac principle generally needs an upsampled digital signal for proper operation?
I think it is possiple without, and there is a NOS Filter available, it sounds pretty good, but you have quite a bit ultrasonic hash left than, which might upset some class d amps and I, at least, feel, that there are alasing artefacts... the dam is still upsampling then, by the way, but the filter is turned of, so it working NOS Up to 384khz, from there it is still oversampling up to the mhz region... That frequency drives the ladder, but that should not have an impact on what we hear
Hi Hop.sing
Thanx for answering!
I have downloaded the 'partypak' and allready tried the NOS- implementation there.
But from what I've read this NOS- 'filter' at least leads into an upsampling process.
What I'm really interested in is:
Is it possible to play 16bit 44.1khz wav.files without oversampling and upsampling with the DAM 1021?...and if, has anyone tried this?
Greetingz, Robert
Thanx for answering!
I have downloaded the 'partypak' and allready tried the NOS- implementation there.
But from what I've read this NOS- 'filter' at least leads into an upsampling process.
What I'm really interested in is:
Is it possible to play 16bit 44.1khz wav.files without oversampling and upsampling with the DAM 1021?...and if, has anyone tried this?
Greetingz, Robert
I spent time reading the related posts and, unfortunately, did not find a conclusive answer I was looking for. I think this post posted by Soren states that dam1021 does both upsampling and oversampling. See http://www.diyaudio.com/forums/vend...magnitude-24-bit-384-khz-168.html#post4221487
If this is the case, the question is, how to disable these in a quest of purist audio approach. That is, to get the analogue output based on digital input without any additional processing, up- downsampling, filtering, additions, deductions, multiplications, or other manipulations intended to 'improve' the original signal.