Anybody know what additional amount of capacitance is optimal for the rev3 / rev4 vref buffers? There is three mounting holes for caps on each rail, and i know in the older buffers to much capacitance was even negative.
So what would be best with latest rev per rail? 3x820uF? 3x1000uF? 3x1200uF?
So what would be best with latest rev per rail? 3x820uF? 3x1000uF? 3x1200uF?
After monitoring commands sent from volume pot when I played music from Raspberry Pi (RPi) via Input Board, I found the command values sent from volume pot was unstable and caused the aforementioned noise issue.
Then I detached RPi from Input Board and played music via coaxial of Input Board, the volume pot worked perfectly. Does anyone experience the same issue when use volume pot with RPi attached to Input Board? Any comment appreciated.
Then I detached RPi from Input Board and played music via coaxial of Input Board, the volume pot worked perfectly. Does anyone experience the same issue when use volume pot with RPi attached to Input Board? Any comment appreciated.
I've removed the transformer, replaced it with 1k/82r parallel combo (= 75.6ohms), using spdif1+/- , 1k -> 1.2v, and gnd and I still get no lock...
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Awesome! very nice build Steven!
A rubidium clock too!
Please share the list of components you chose for your build!
Thanks for sharing!
Dear everyone,
I have designed input board for dam1021 and tested it in this month.
And I have a problem when I test it:
--
When I select COAX input and AES has still signal input too, the COAX signal will be interference.
The following is interference:
1. The high frequencies part of music will be disappear sometimes.
2. The background may have additional noise when the music playing but without noise when the music stop.
On the contrary, when I select AES input and COAX still signal input too, the AES signal is stable.
Then I disconnect the S/PDIF2 line from J3 of dam1021 the COAX signal will become stable.
--
Has anyone encountered this problem too?
Thanks a lot!
====
The input setup as following:
COAX: S/PDIF 1 (+/-)
AES: S/PDIF2
USB and I2S(via HDMI): isolated I2S.
The dam1021 module is Rev.3 with R1.05 firmware, and the power supply is regulated +/-10V DC.
I have designed input board for dam1021 and tested it in this month.
And I have a problem when I test it:
--
When I select COAX input and AES has still signal input too, the COAX signal will be interference.
The following is interference:
1. The high frequencies part of music will be disappear sometimes.
2. The background may have additional noise when the music playing but without noise when the music stop.
On the contrary, when I select AES input and COAX still signal input too, the AES signal is stable.
Then I disconnect the S/PDIF2 line from J3 of dam1021 the COAX signal will become stable.
--
Has anyone encountered this problem too?
Thanks a lot!
====
The input setup as following:
COAX: S/PDIF 1 (+/-)
AES: S/PDIF2
USB and I2S(via HDMI): isolated I2S.
The dam1021 module is Rev.3 with R1.05 firmware, and the power supply is regulated +/-10V DC.
Attachments
Dear Dimdim,
The schematic of COAX input is based on dam1021's user manual, and only the 1.2V supply is modified: I select LM4041-1.2(shunt voltage reference).
The schematic of AES input select DS90LV012 to translate to TTL signal for SPDIF2.
The 3.3V supply is from J3 of dam1021 board.
Thanks a lot.
Attachments
I don't know about the noise problem, but your AES input is no good, you can't use a LVDS receiver there without a voltage divider as the input voltage can be higher the its max spec. I'll recommend a RS422 receiver, see dam1121 example schematics.
1. DAM1021 Case: https://item.taobao.com/item.htm?id=17218854916
2. Rubidium Case: https://item.taobao.com/item.htm?spm=a230r.1.14.152.C2WHbj&id=22548235665&ns=1&abbucket=10#detail
3. Regulated power supply board +/-12v for DAM1021 ：https://item.taobao.com/item.htm?spm=a1z09.2.0.0.qDwlow&id=529453278199&_u=e1okcer33042
4. Transformer 50VA for DAM1021 and Tube buffer ： https://item.taobao.com/item.htm?spm=a1z09.2.0.0.qDwlow&id=14005531061&_u=e1okcer3ee20
5. Crystal board 22.5792M and 24.576M for Amanero ：https://item.taobao.com/item.htm?spm=a1z09.2.0.0.qDwlow&id=528569785461&_u=e1okcer3a5f1
6. JENSEN JT 123-s Audio Transformer：https://item.taobao.com/item.htm?spm=a1z09.2.0.0.qDwlow&id=524283985941&_u=e1okcer3b055
7. DAM1021 Display board ：https://item.taobao.com/item.htm?spm=a1z09.2.0.0.qDwlow&id=520832497451&_u=e1okcer379cd
8. Tube buffer board(X-10D) ：
https://item.taobao.com/item.htm?spm=a1z09.2.0.0.qDwlow&id=18874847033&_u=e1okcer35251
9. Rubidium FE-5680A 10MHZ : https://item.taobao.com/item.htm?spm=a1z09.2.0.0.qDwlow&id=521327229622&_u=e1okcer37209
10. Rubidium display board : https://item.taobao.com/item.htm?spm=a1z09.2.0.0.qDwlow&id=42929796788&_u=e1okcer3aeb6
11. HQPlayer : Signalyst
12. MUSO : http://klarita.net/muso.html
13. AUDIOPHILE OPTIMIZER : Highend-AudioPC | AudiophileOptimizer
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I like the input board you have made! Are you planning to have that available for sale by chance? It appears you have HDMI i2s? I have been looking for that for a while. Hmm. If you get the bugs out of this board please keep me in mind, I would love to try one of these boards if it's possible 🙂
Keep up the great work Bill.
Dear soekris,
Thank you for your suggestion. I will take it into account in next version.
I will measure the AES signal voltage later to confirm whether higher input voltage induced interference on COAX or not.
Thanks a lot.
Dear bimmer100,
The transmission of I2S signals via HDMI is based on the “I2S over HDMI (PS Audio)”.
The USB and I2S use isolated I2S interface of dam1021 DAC, and high-bandwidth bus switch IC to select USB or I2S.
I will try to debug as far as possible.
Thank you for your attention.
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Dear derekr,
I use the TI's SN74CB3Q3257 as bus switch, and use logic gate circuits to control SN74CB3Q3257 status.
Listening Impression Thread??
Is there a thread on listening impressions??
Would like to know people's experiences in general.
Especially WRT the system it is being used with and compared to other "known" units.
Other than the DIY aspect, it's difficult for me to figure out if the effort to build this up is
justified by the sound alone. Also Soekris offers a DAC unit that is very similar and already functioning and built.
Getting a handle on this would be useful to me.
tnx.
_-_-bear
Is there a thread on listening impressions??
Would like to know people's experiences in general.
Especially WRT the system it is being used with and compared to other "known" units.
Other than the DIY aspect, it's difficult for me to figure out if the effort to build this up is
justified by the sound alone. Also Soekris offers a DAC unit that is very similar and already functioning and built.
Getting a handle on this would be useful to me.
tnx.
_-_-bear
Hello Bear,
I'm fully with you about what you wrote. And I believe the Soekris was certainly the first DIY dac where the diyers contributed as much as the designer to get it sounding better (I bought the stock one and sold it immediatly when I understood it will bring me much more money and time I hadn't to make it sounding good . Frankly the stock one was very bad and bellow what a simple ESS integrated chip could do !).
As there are certainly so many different Soekris today + the more smiling OEM unit without the integrated PS, it could be interressant to have more testimonials.
On my side I spent time on the AYA II from Audial than P. Rogic redisigned for a small group of nostalgic and I don't regret the little time I spent on it in relation to the greater one than people spent on the Soekris (but thanks to collaborativ and fine people whom shared, the Soekris certainly greatly improved whatever says the scope o fthe former designer...). I added some of the better stuffs of IanCanada on it, and it's interresting to uerstand the chip, the resolution, the bit depth make not all the story ! You can go very deep in information and musicality with 16/44 ! Most of people try to win of the resolution side but their hifi still sounds crapy !
I know also some nice belgiums guys whom have both dacs benchmarked them and it's good to know sometimes, despite the spec of moderner units, the omd ones can be as musical....
I'm fully with you about what you wrote. And I believe the Soekris was certainly the first DIY dac where the diyers contributed as much as the designer to get it sounding better (I bought the stock one and sold it immediatly when I understood it will bring me much more money and time I hadn't to make it sounding good . Frankly the stock one was very bad and bellow what a simple ESS integrated chip could do !).
As there are certainly so many different Soekris today + the more smiling OEM unit without the integrated PS, it could be interressant to have more testimonials.
On my side I spent time on the AYA II from Audial than P. Rogic redisigned for a small group of nostalgic and I don't regret the little time I spent on it in relation to the greater one than people spent on the Soekris (but thanks to collaborativ and fine people whom shared, the Soekris certainly greatly improved whatever says the scope o fthe former designer...). I added some of the better stuffs of IanCanada on it, and it's interresting to uerstand the chip, the resolution, the bit depth make not all the story ! You can go very deep in information and musicality with 16/44 ! Most of people try to win of the resolution side but their hifi still sounds crapy !
I know also some nice belgiums guys whom have both dacs benchmarked them and it's good to know sometimes, despite the spec of moderner units, the omd ones can be as musical....
Yes, so there is no specific thread about the sound - anyone?
If not I will start one and post the link here.
I am curious since the FFT perhaps does not look as nominally spectacular as some "chip" based DACs, and the nominal THD does not either. But this does not tell the entire story.
Tube amps don't spec well, but can sound great.
Also the option of different downloadable filters is very interesting.
_-_-
If not I will start one and post the link here.
I am curious since the FFT perhaps does not look as nominally spectacular as some "chip" based DACs, and the nominal THD does not either. But this does not tell the entire story.
Tube amps don't spec well, but can sound great.
Also the option of different downloadable filters is very interesting.
_-_-
Problem is this is a diy forum and therefore you are not likely to find comparisons with 'known' units. There are comparisons that have been done elsewhere. You can search head-fi, changstar, tirnahifi... just google search.
The rev3 Soekris is certainly better than any retail dac I've heard under $500, and I've heard a lot of them. Others put it as good as or just below Schiit Yggdrasil or whatever their multibit is called.