Hi!
Is the Aurora what I need?
2 Spdif or AES in -> 8 channel adat out
Is that possible and how difficult is it to setupcomparred to MiniDSP- Do I need to flash the unit or do I connect it to my network and then it's plug & play with the browser?
RS PRO, Jack Fibre Optic Connector, Toslink | RS Components Is this all I need to make it output adat or do I need somekind of multicontroller?
In advanced sorry for stupid questions, I have been searching for some days for answers without getting answers- this could really be the solution of my dreams- thank you!
Is the Aurora what I need?
2 Spdif or AES in -> 8 channel adat out
Is that possible and how difficult is it to setupcomparred to MiniDSP- Do I need to flash the unit or do I connect it to my network and then it's plug & play with the browser?
RS PRO, Jack Fibre Optic Connector, Toslink | RS Components Is this all I need to make it output adat or do I need somekind of multicontroller?
In advanced sorry for stupid questions, I have been searching for some days for answers without getting answers- this could really be the solution of my dreams- thank you!
Aurora multiChannel DIGITAL out?
Hi folks
I was part of the kickstarter, but haven't really started to experiment with Aurora yet. Studying the documentation, I cannot at the moment understand how to achieve multichannel DIGITAL out. 4 channels is my absolute minimum, feeding separate DACs. Documentation says spdif/adat out, as well as sub 8x input and ouput.
As it seems, I do need an additional unit to fetch out the digital output after DSPing etc. Do I understand correctly?
If so, is there any recommended or possible solutions?
If anyone could drop a few lines regarding this need, I will be appreciated. It will be a timesaver for me. Thank you.
Hi folks
I was part of the kickstarter, but haven't really started to experiment with Aurora yet. Studying the documentation, I cannot at the moment understand how to achieve multichannel DIGITAL out. 4 channels is my absolute minimum, feeding separate DACs. Documentation says spdif/adat out, as well as sub 8x input and ouput.
As it seems, I do need an additional unit to fetch out the digital output after DSPing etc. Do I understand correctly?
If so, is there any recommended or possible solutions?
If anyone could drop a few lines regarding this need, I will be appreciated. It will be a timesaver for me. Thank you.
@dspverden correct me if I'm wrong, but I don't think ADAT functionality has been implemented yet? At the very least I don't think it's available with the current WebApp or AuverdionControl UI.
I'm currently waiting on official support for ADAT functionality and 8 channel FIR control myself. Bodging those in has so far proved unsuccessful...
Measuring from my lab bench supply I'm getting about 500-650mA @ 9v (I do have additional hardware connected but should be minimal draw). As far as ripple, everything's on linear regulators so any reasonable 1A power supply should do fine.
Thanks. An LM317-based supply would be fine? Or even a basic linear unregulated (e.g. wall-wart transformer -> diodes -> moderate capacitance)?
@sudermap, thanks. I assume that internal routing to the 8 DACs are based on I2S. Therefore, will it in any way be possible to connect to those i2s signals? That would solve it for me as my DACs hare compliant. (They are also SPDIF compliant).
An alternative would be the return channels of the USB, if there is a multichannel USB card available with the option to extract e.g. i2s both ways, so that the return signal from Aurora could be picked up there.
Possible?
An alternative would be the return channels of the USB, if there is a multichannel USB card available with the option to extract e.g. i2s both ways, so that the return signal from Aurora could be picked up there.
Possible?
On-board routing is TDM8 (with the exception of the 2 channel freeDSP expansion header), so if you have I2S signals you would need an external XMOS or an audio codec to do 4x I2S to TDM8 Transcoding. It's totally doable if you plan it out, but I have been reluctant to modify my board too heavily vs wait for ADAT implementation.
You can find full schematics here which should have all your header and bus information.
If you do manage to get I2S-to-TDM8 working on your board please let me know! I'm currently doing I2S->ADAT Out->ADAT In->Aurora, so that would save me a step.
Sorry, but I am not versed in internal PCB routing, so your need will most likely not be solved by me. On the contrary, I am in a learning process. In that layman perspective, I now have a worry about the Aurora's ability to provide MULTICHANNEL DIGITAL out. In the Aurora manual/getting started, it says:
"Digital Audio Connections:
On connector X101 you can make your digital audio connections like S/P-DIF input and output and ADAT input and output. Wordclock input and output can be connected to X101, too."
That is all in the current version, which make me suspect that my need is currently not-yet within scope of this board's features. The freeDSP expansion header seems to be stereo only, which makes it uninteresting (?).
I am wondering, are we the only ones in the world seeking a solution that can provide multichannel digital out? Would be hard to believe, because it is a very interesting option that can create great flexibility. One example is that you can use your "one million dollar" DAC instead of the DACs normally used on such DSP boards. From my point of view, this is clearly a major need in some cases. So:
Our need: I attach a drawing. It says that a 2x stereo input from usb (or optical) is processed through the Aurora, resulting in the original 2x stereo input also as output (however subject to EQ DSP modifications, etc), as well as an additional 2x stereo (rear) signal that is at the core of our functionality. This is an algorithm correcting for acoustic crosstalk. We have since 10 years a 2x atereo version of that on soundpimp.com (listen to our demos to grasp the essence of it), but we are now expanding that to a 4x version (which is MUCH better), and we are migrating from sw solution to HW solution. We have it kind of working on an ADAU evaluation board. Therefore, our minimum output from Aurora must be 4x digital out. (The other 4x is not used in this drawing, but we have a usage for those as well, to feed subwoofers, but that is omitted in this explanation for simplicity).
The main point here is therefore to be able to extract ALSO the 2x rear stereo signal out of Aurora.
Possible solutions, and here is where I need some help:
1. The TDM8 output of the ADAU1452, it is on Aurora going into separate DACS for a total of 8x ANALOG output. Does this mean that these DAC modules themselves are extracting their respective 2x channels out of the TDM8? I would assume that this is NOT the case, but that there is an "extractor" in between the ADAU and these DACS that extracts an i2s signal from the TDM8. Thanks for enlightening me if I am wrong.
2. Alternatively, the only possible option I can see at the moment, would be a product like the MiniDSP MCHstreamer (miniDSP launches the MCHStreamer, a multichannel multiprotocol USB audio interface) that may be able to take advantage of the Aurora 8x full duplex USB audio OUTPUT (= return channel?) which is assumed to be TDM8 on the bus. IOW, that the end results out of Aurora; i.e. the two 2x stereo signals that is output from the two DSP modules (AurverdionControl and HDSL DSP, respectively), can be fetched out of the MCHStreamer TDM8 to i2s expansion module. One showstopper here, would be that this MCHStreamer may only provide i2s multichannel outputs on its USB input stream, in which case this alternative 2 would not work. I am going to ask MiniDSP about that.
In the current version of Aurora, am I stuck, or could any of these solutions work (perhaps with a little soldering out the i2s signals)?
Further to this, we have the ADAT, but the problem with that protocol seems to be that it is really not implemented in many boards, if any at all? At the moment, we are developing our 4x soundpimp system in software, and then we use a RME Digiface having 4 optical outs, freely configurable as ADAT or SPDIF. We use the latter for direct compliance with our DACs. So, everything is working in software, and therefore I have indicated 4ch input via USB for prototyping. However, that is not very important. The importance is the multichannel digital out of Aurora.
Thanks for any clarifying remarks.
Attachments
Hi,
you can just open the SigmaStudio project, setup SPORTOUT3 with TDM8 or TDM4 and the right clock configuration for your additional DACs. Your extra DACs need to support TDM of course. In the SigmaStudio project you can connect the channels to SPORT3 like you need them, perhaps you want the output of the signal processing chain or use the ADC input or whatever. Then you have to upload your new firmware as described above. You can pick up your TDM signal on X102.
Raphael
@Kyrre
TDM is a common routing protocol for DACs. TDM compliant DACs have a pass-through function, where they either strip out the data they process (i.e. TDM10 in, TDM6 out + first 4 analog) or they are programed to only process certain channels (i.e. TDM8 in, TDM8 out + channel 5 & 6 analog). In the case of Aurora, there is a single 8 channel DAC and a single 8 channel ADC, so they do not use the pass-through function.
I've worked with MCHStreamer before and it does not do TDM8 to I2S transcoding, it's an XMOS based USB client interface witch allows a host computer to send/receive either TDM8 or I2S, but it does not convert the two internally. Aurora is also a USB client device so the two cannot be connected over USB without a host computer and additional latency.
As far as ADAT goes, this is a very common interface for a large variety of professional audio interfaces. If you need to convert ADAT to I2S this can be done via XMOS or stand alone transceivers (CoolAudio V1402 is what I use, as it is hobbyist friendly).
I notice on your example however that all the data-streams eventually go to DACs, is there any reason why you can't just use the DAC output of Aurora? This would greatly simplify your design.
TDM is a common routing protocol for DACs. TDM compliant DACs have a pass-through function, where they either strip out the data they process (i.e. TDM10 in, TDM6 out + first 4 analog) or they are programed to only process certain channels (i.e. TDM8 in, TDM8 out + channel 5 & 6 analog). In the case of Aurora, there is a single 8 channel DAC and a single 8 channel ADC, so they do not use the pass-through function.
I've worked with MCHStreamer before and it does not do TDM8 to I2S transcoding, it's an XMOS based USB client interface witch allows a host computer to send/receive either TDM8 or I2S, but it does not convert the two internally. Aurora is also a USB client device so the two cannot be connected over USB without a host computer and additional latency.
As far as ADAT goes, this is a very common interface for a large variety of professional audio interfaces. If you need to convert ADAT to I2S this can be done via XMOS or stand alone transceivers (CoolAudio V1402 is what I use, as it is hobbyist friendly).
I notice on your example however that all the data-streams eventually go to DACs, is there any reason why you can't just use the DAC output of Aurora? This would greatly simplify your design.
Aurora is little bit shy on external io, connections from ADAU1452 or XMOS chip to the outside word. XMOS could do the tdm to 4x spdif conversion easily but there should be enough 1- bit ports connected to extension headers. Then the pcb should be a little bit larger. For tdm to i2s conversion you need some external board: xmos, microcontroller, fpga or other pld like the PSoC 5LP on this inexpensive board: https://www.cypress.com/documentati...oc-5lp-prototyping-kit-onboard-programmer-and
@Sudermap, @dspverden and @mhelin, thanks for helpful responses. I am more optimistic. My response:
1. Yes, indeed, the internal DAC may be used, at least for prototyping and testing, but a key point in the design is freedom of choice, i.e. meeting an expectation that it should be possible to use your own DAC. DAC is religion, so to speak. One of our DACs is the Audiophonics 9038 ESS SABRE + Kali Masterclocking, well reputed. We are looking into this DAC as a HW plugin option in the control amplifier that contains all this.
Is there anything to say about the proven quality of the built-in DAC? For example, is the same solution in some commercial DAC with thumbs up reviews?
We also have active speakers with AES digital input (and analog input). In the latter case you get a series of ADC and DAC conversions. Which is better, to feed the speaker with AES3, or analog? AES3 is better, i.e. digital out is needed, and the sub may also (typically) be subject to particular subwoofer<->Room dedicated EQing in the Aurverdion control, not equal to the DSP on the main speakers. So, multichannel digital out is the salvation.
2. @dspverden. As stated, multichannel DIGITAL out is mandatory for us. Would the creation of an add-on pcb plugin offering TDM8 to 8x i2s conversion be a candidate? It would make the Aurora a complete multipurpose unit without limitations. Having said that, if Aurora becomes part of a commercially available product (the ambition), then we would most likely make a proprietary variant as loosely suggested by @mhelin. But that is a future possible step, and now we are prototyping only.
3. @mhelin, the supress device, is it easy to program it to take TDM8 as input, and deliver 8x i2s on its output?
4. on ADAT: It lacks in practical PCB implementations, but is a better choice than SPDIF. Even better would be the MADI optical due to unlimited multichannel possibilities. If e.g. the freeDSP project decided to make a board that can take on its input: SPDIF, MADI, ADAT, and convert to i2S and/or TDM, it would open up a new landscape of flexibility. I do not understand the logic behind the freeDSP expansion slot, with its 2x only. Why did they not design at least 8x?
1. Yes, indeed, the internal DAC may be used, at least for prototyping and testing, but a key point in the design is freedom of choice, i.e. meeting an expectation that it should be possible to use your own DAC. DAC is religion, so to speak. One of our DACs is the Audiophonics 9038 ESS SABRE + Kali Masterclocking, well reputed. We are looking into this DAC as a HW plugin option in the control amplifier that contains all this.
Is there anything to say about the proven quality of the built-in DAC? For example, is the same solution in some commercial DAC with thumbs up reviews?
We also have active speakers with AES digital input (and analog input). In the latter case you get a series of ADC and DAC conversions. Which is better, to feed the speaker with AES3, or analog? AES3 is better, i.e. digital out is needed, and the sub may also (typically) be subject to particular subwoofer<->Room dedicated EQing in the Aurverdion control, not equal to the DSP on the main speakers. So, multichannel digital out is the salvation.
2. @dspverden. As stated, multichannel DIGITAL out is mandatory for us. Would the creation of an add-on pcb plugin offering TDM8 to 8x i2s conversion be a candidate? It would make the Aurora a complete multipurpose unit without limitations. Having said that, if Aurora becomes part of a commercially available product (the ambition), then we would most likely make a proprietary variant as loosely suggested by @mhelin. But that is a future possible step, and now we are prototyping only.
3. @mhelin, the supress device, is it easy to program it to take TDM8 as input, and deliver 8x i2s on its output?
4. on ADAT: It lacks in practical PCB implementations, but is a better choice than SPDIF. Even better would be the MADI optical due to unlimited multichannel possibilities. If e.g. the freeDSP project decided to make a board that can take on its input: SPDIF, MADI, ADAT, and convert to i2S and/or TDM, it would open up a new landscape of flexibility. I do not understand the logic behind the freeDSP expansion slot, with its 2x only. Why did they not design at least 8x?
Last edited:
Regarding 3)
I was wrong about the TDM support for PSoC 5LP, I saw an I2S_PDL component on Cypress site but it was not an updated version of the old I2S component for all devices, it was only for the new PSoC 6 devices like the one on this kit:
https://www.cypress.com/documentati.../psoc-6-ble-prototyping-kit-cy8cproto-063-ble
That is not too expensive yet for $20. You can (if you can) use the PSoC Creator IDE and create a top design with a single I2S_PDL component which you configure as I2S Rx Slave for TDM A (I guess, or TDM B) with 8 channels, 32 bit word and channel lenghts, single bit frame clock. In addition you need four I2S Tx Slave component instances plus DMA for all of them, or alternative use FIFO and Cortex M4 code to read the FIFO of the TDM channel and output the separated channels to the four I2S channels (via FIFO or using DMA). If you use the dev kit above you have also BLE support though I have no idea what you would do with it.
Regarding 4) If you had a device for TDM8 to/from 4xI2S (using left or right justified modes instead) you could use easily the CoolAudio V1401 and V1402 chips for ADAT I/O.
Unfortunately that is not working, it seems you can only use a single I2S component on the PSoC 6 design where PSoC 5LP allows for multiple I2S connections from the single component. PSoC 6 I2S component limits I2S channels to 2. You can make the topdesign fine but the build fails with "Resource limit: Maximum number of I2S exceeded (max=1, needed=5)".
You could implement this on XMOS fine but unfortunately you should then design your own board as there are no inexpensive XMOS boards available anymore, the startKit maybe if you happened get them while the were available. Maybe some microcontrollers could do this, some STM32F4 variants maybe have the resources needed.
Last edited:
Btw. audverion/freeDSP Infinitas board has a Lattice FPGA with the headers which could be used for TDM <-> I2S/LJ conversion:
freeDSP-Infinitas from auverdion on Tindie
Documentation with schematics:
freeDSP-INFINITAS/GettingStarted.pdf at master * freeDSP/freeDSP-INFINITAS * GitHub
Just leave the other chips (ADAU1452 and XMOS) unpopulated, I think the FPGA is already configured for TDM/I2S conversion but the TDM audio signals maybe are not routed to any headers. Not a big change to do as you don't need the I2C pins for anything.
freeDSP-Infinitas from auverdion on Tindie
Documentation with schematics:
freeDSP-INFINITAS/GettingStarted.pdf at master * freeDSP/freeDSP-INFINITAS * GitHub
Just leave the other chips (ADAU1452 and XMOS) unpopulated, I think the FPGA is already configured for TDM/I2S conversion but the TDM audio signals maybe are not routed to any headers. Not a big change to do as you don't need the I2C pins for anything.
Last edited:
You would think the user manual has this info... or how much power it consumes... or what resistance potentiometer to hook up.
