rkn80

Re: Modular multi channel DIY AD/DA Box
« Reply #440 on: December 12, 2010, 11:40:34 AM »
The schematic of the clocking board is done.
Please note that this is a version with the intionention of having it running after soldering meaning that you don't have to program a device.
We discussed DDS and Microcontroller based solutions prior maybe such a solution will come in the future. It would be nice but I've currently no concrete plans to go there.

Raphael


jdbakker

Re: Modular multi channel DIY AD/DA Box
« Reply #441 on: December 12, 2010, 06:11:37 PM »
Nice.

IC17 won't be too happy with pins 1 and 4 shorted. It's not entirely clear to me why you use a comparator here, either.

Same comments I made previously on sharing buffers applies here.

Instead of IC18 you might as well use a VCXO for OSC1 (DigiKey has the ASVTX-11-A-24.576MHZ, RS have a few but the Fox ones have suboptimal phase noise). In that case you may need to square up the 0.8Vpp clipped sine output; several circuits can be found at http://www.wenzel.com/documents/waveform.html .

JDB.
[that CDCE913 does the job, but its jitter performance isn't exactly stellar]


rkn80

Re: Modular multi channel DIY AD/DA Box
« Reply #442 on: December 22, 2010, 05:00:09 PM »
Here is now the first layout for the clocking board.

JDB, do you have part numbers of the single logic parts for the output buffers?
Well I know that the CDCE913 does not perform like a DDS but I think the arrangement in a PLL like this will outperform many other designs/integrated solutions.

Raphael

P.S. The length matches the length of the mainboard. Therefore you see some unused space on the PCB but it make easier to mount and connect the PCB to several mainboards because you can do that via a rack style arrangment.

« Last Edit: December 22, 2010, 05:04:51 PM by rkn80 »

jdbakker

Re: Modular multi channel DIY AD/DA Box
« Reply #443 on: December 23, 2010, 09:05:56 AM »
JDB, do you have part numbers of the single logic parts for the output buffers?

74ACH1G125 (negative OE)
74ACH1G126 (positive OE)

or use simple gates, like the 74ACH1G08, so that when the driver is disabled the output isn't floating.

JDB.

deuce42

Re: Modular multi channel DIY AD/DA Box
« Reply #444 on: December 24, 2010, 02:22:28 AM »
At the risk of dragging this thread down to a level of only slightly above that of a moron, can I just confirm where this project is up to so I can get my head around it and understand (and apologies in advance to you guys if I sound like such a fool for having to ask this)

So can I confirm the following assumptions:.

1) A/D converters kits and PCB's have been distributed.
2) D/A will be distributed when they become in stock.  
3) Both need a power supply created for them at 15v.
4) Both boards could be interfaced with a PC by using something like Mikkel's opto rec or opto gen lightpipe boards.
5) If you dont use optical adat in/ out like Mikkel's boards, the alternative is the clock board you guys are discussing here which would interface with the PC
6) Some sort of software will need to be written to get these boards to talk to the PC.


Is this all correct and am I missing anything else?

Thanks for your patience and thanks Raphael for making this project available:)

« Last Edit: December 25, 2010, 03:25:30 AM by deuce42 »

rkn80

Re: Modular multi channel DIY AD/DA Box
« Reply #445 on: December 24, 2010, 03:46:33 AM »
No Problem.

ad 1)-4) you are right.
ad 5)-6) you are wrong. The clocking board we are discussing is an option to improve the clocking (jitter) Performance and to add features like wordclock sync.
If you don't want to go via ADAT you can use the AES interface boards which are already designed and partly distributed.

JDB, thanks for the numbers, that makes it easier to find them in distrbutors inventory.
The TL331 forms a 1.8V clamp.

I wish you all Merry Christmas!

Raphael

deuce42

Re: Modular multi channel DIY AD/DA Box
« Reply #446 on: December 25, 2010, 03:27:41 AM »
Am I right in saying that for this project, you would still need another audio interface to connect between this project and the pc- ie either connect between the audio interface with lightpipe adat or with AES?

Without an existing audio interface, is it correct that there is no other way of connecting this to the computer? Ie not like firewire etc?  

I guess my question is becuase I want an AD/DA converter that I can connect to a laptop but if the laptop only has firewire or usb connections, I may still need another audio interface that has something like firewire and lightpipe or AES connects.

Is this correct?
« Last Edit: December 25, 2010, 03:30:04 AM by deuce42 »

rkn80

Re: Modular multi channel DIY AD/DA Box
« Reply #447 on: December 27, 2010, 01:04:04 PM »
Yes you are right. To use this project you still need an interface with AES or ADAT. But maybe someone Else will come with an USB solution or something like that in the future.

Raphael

rkn80

Re: Modular multi channel DIY AD/DA Box
« Reply #448 on: January 02, 2011, 07:08:43 PM »
Hi,

I just want to inform that I'm going to etch the first prototype of the clocking board tomorrow.
JDB please forgive me, I did change the output drivers to single gate devices because I want to test the design first before I do the fine tuning. I'm pretty shure that there will be changes... Therefore, the single gates will come in rev B. ;)

Raphael

JBVries

Re: Modular multi channel DIY AD/DA Box
« Reply #449 on: January 18, 2011, 12:28:56 PM »
Hi Raphael,

I have been interested in this project ever since I saw the thread a while
back.

I know it's likely difficult to compare the quality/sound to anything tht exists in te consumer realm, but could you venture a guess?

Are the converters more along the lines of a Mytek or a Motu? I know those are very differed but any info you could give on the accuracy and relative quality compared to whats out there would be greatly appreciated.


Cheers,
JB
A little bit of the sonic mayhem I bring to the table.....

http://www.soundcloud.com/jbvries


rkn80

Re: Modular multi channel DIY AD/DA Box
« Reply #450 on: January 23, 2011, 08:42:36 AM »
JB, you're read it is hard to say anything about the sound compared to Mytek or Motu. In fact I never owned one of their devices.
Anyway, from that what is used for this project (DACs, ADCs etc.) we're playing in the league of Digidesign Protools or SSL Alpha-Link looking at their spec's and what I've used.

Btw. these commercial devices are not expensive because they used really expensive converters. No. They are expensive because they use many converter chips to get many channels... ;)

Raphael

Btw. We need a name for this project. Any ideas?

tmuikku

Re: Modular multi channel DIY AD/DA Box
« Reply #451 on: January 25, 2011, 07:17:26 AM »
Yellow!

How is everybody?:) I thought to post since ethernet based connectivity seems to be a step closer. I don't know if you all are already aware of Audinate Dante, an audio over ethernet solution? I just noticed Focusrite has launched new product line that uses Audinate Dante (REDNET) and user BR seems to have some DIY friendly product coming along the line http://www.groupdiy.com/index.php?topic=42004.0  

It seems that Audinate doesn't require expensive license since they sell virtual soundcard driver and various ready made hardware solutions to transfer audio over ethernet. For example, they have card called Brooklyn that accepts I2s and has 64 x 64 IO with 48kHz sampling. One can find some sort of datasheet from support > documentation but it needs registering. http://www.audinate.com/ They also have evaluation board available.

Is anybody familiar with this? Is Dante something that DIY people can get hold to without significant monetary investment or am I just dreaming?:)

« Last Edit: January 25, 2011, 07:21:29 AM by tmuikku »

rob_gould

Re: Modular multi channel DIY AD/DA Box
« Reply #452 on: January 25, 2011, 09:38:07 AM »

Thanks Raphael my parcel turned up today :)

I'll get thinking on the name of the project!

tmuikku : Yes - I saw the REDNET and it made me think of this project.  Could be an interesting development...

Re: Modular multi channel DIY AD/DA Box
« Reply #453 on: January 25, 2011, 02:17:43 PM »
Btw. We need a name for this project. Any ideas?

i vote for 'die lange reise'  ;).
There's nothing like the right tool for the job.
And -usually- that's what I end up using...
..nothing like the right tool for the job!

rob_gould

Re: Modular multi channel DIY AD/DA Box
« Reply #454 on: January 25, 2011, 04:35:11 PM »
Btw. We need a name for this project. Any ideas?

i vote for 'die lange reise'  ;).

Cheeky  :D

Re: Modular multi channel DIY AD/DA Box
« Reply #455 on: January 25, 2011, 04:37:56 PM »
Cheeky  :D

texas instruments has been a cold, cruel mistress.  :'(
I actually meant it more as a testament to raphael's continued effort.

What about AD/DAble? Sums up (pun intended) the modular/expandable nature of the project rather well.
« Last Edit: January 25, 2011, 07:55:50 PM by grantlack »
There's nothing like the right tool for the job.
And -usually- that's what I end up using...
..nothing like the right tool for the job!

deuce42

Re: Modular multi channel DIY AD/DA Box
« Reply #456 on: January 26, 2011, 12:40:40 AM »

[/quote]

i vote for 'die lange reise'  ;).
[/quote]

I like that:)

Kingston

Re: Modular multi channel DIY AD/DA Box
« Reply #457 on: January 26, 2011, 01:27:19 AM »
I've just called it the rkn80 converter this far, when I've gathered all the documentation and needed a name for the folder.

Re: Modular multi channel DIY AD/DA Box
« Reply #458 on: January 26, 2011, 01:38:23 AM »
Maybe A/DIY/A.

Flo

Re: Modular multi channel DIY AD/DA Box
« Reply #459 on: February 06, 2011, 12:32:04 PM »
Got my package. Thanks, Raphael.

I guess I should have payed attention and got an SMD station instead of the wd2 I just scored off of eBay. My bad. That certainly makes this project more daunting, but hey...  Half the reason I do DIY is to learn.


 

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