Just got the the WONDOM ADAU1701 APM2 without the extension board so I could basically use it as a pre-amp. But I'm unfortunately unable to find a wiring diagram to connect the APM2 in a 2.1 setup without the extension board, would anybody be able to help?
Thanks!
Thanks!
Attachments
Here's a LINK to the Sure document that should answer your questions. A couple of things to note if you're using the Sure SigmaStudio project:
1). DACs 2 & 3 both get the summed .1 signal
2. The .1 signal is band passed, not just low passed. As you adjust the pot the high pass filter goes from 20 to 200 Hz while the low pass goes from 100 to 300 Hz. I can't think of any situation where I would want that type of operation.
IMO the supplied project is worthwhile only for playing around to get familiar with SigmaStudio. There are several other problems/limitations too. So any serious application requires learning SigmaStudio and building a new project. I'd recommend the miniDSP 2X4 if you're looking for an easy to learn, ready out of the box solution. YMMV.
1). DACs 2 & 3 both get the summed .1 signal
2. The .1 signal is band passed, not just low passed. As you adjust the pot the high pass filter goes from 20 to 200 Hz while the low pass goes from 100 to 300 Hz. I can't think of any situation where I would want that type of operation.
IMO the supplied project is worthwhile only for playing around to get familiar with SigmaStudio. There are several other problems/limitations too. So any serious application requires learning SigmaStudio and building a new project. I'd recommend the miniDSP 2X4 if you're looking for an easy to learn, ready out of the box solution. YMMV.
To use the SURE ADAU DSP, you have to learn Sigma Studio and buy a connecting device. Even installing this software with drivers and connecting the ADAU to it, is quite "interesting".
If you get that far and know a lot about filters and analog signal stuff, like to solder under a microscope and have a lot of time, you may end up with a very uncomfortable end product that sometimes even may work.
I know of very few products that are so user unfriendly in any aspect, hard and software, despite being sold in such great numbers. Not to speak of the non existing customer service of the "SURE Wondom" staff. Chinese after sales service is as rare as a pink Yeti.
I'm sure most of these SURE “DSP” never get used after purchase.
If you just want to use a working 2.1 set-up, better go for some solution with a “simple”, existing user interface. Dayton Audio has some low priced DAC's with a good softwre and USB connection. Some people even use the “miniDSP”.
These devices use the ADAU 1701 chip as well, but you do not need Sigma Studio with an extra interface and can change settings in real time, from a comfortable user interface. USB, too.
THOMANN, if active in your region, got the "the t.racks DSP 4x4 Mini". At 119€ it is the best value for money so far. It is balanced, solid metal and comes with a power supply, Build quality and function make any other comparable product look overpriced.
Compare €119 to the cost of a SURE DSP, Sure Interface, extension board, wires, power supply and shipping. Makes no sense.
The SURE DSP is for small production runs of active speakers and audio gadgets, but much too much hassle for a single consumer project.
If you get that far and know a lot about filters and analog signal stuff, like to solder under a microscope and have a lot of time, you may end up with a very uncomfortable end product that sometimes even may work.
I know of very few products that are so user unfriendly in any aspect, hard and software, despite being sold in such great numbers. Not to speak of the non existing customer service of the "SURE Wondom" staff. Chinese after sales service is as rare as a pink Yeti.
I'm sure most of these SURE “DSP” never get used after purchase.
If you just want to use a working 2.1 set-up, better go for some solution with a “simple”, existing user interface. Dayton Audio has some low priced DAC's with a good softwre and USB connection. Some people even use the “miniDSP”.
These devices use the ADAU 1701 chip as well, but you do not need Sigma Studio with an extra interface and can change settings in real time, from a comfortable user interface. USB, too.
THOMANN, if active in your region, got the "the t.racks DSP 4x4 Mini". At 119€ it is the best value for money so far. It is balanced, solid metal and comes with a power supply, Build quality and function make any other comparable product look overpriced.
Compare €119 to the cost of a SURE DSP, Sure Interface, extension board, wires, power supply and shipping. Makes no sense.
The SURE DSP is for small production runs of active speakers and audio gadgets, but much too much hassle for a single consumer project.
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Already bought the "SURE Wondom ADAU1701" unfortunately, so might as well just see how it goes.
Did you get to the point that you can program it? What do you use between PC and ADAU1701?
If you search, there are some useful applications out there. Best is to take a tried one (not the Wondom examples) and modify them for your needs.
Once you have set things up, you can tune it for your speakers and room. Not very comfortable, but it works.
Sigma Studio is a very mighty tool. Just very easy to do something wrong.
Do not implement too many functions, as the capacity of the Adau is limited, processor power and memory wise. Best to remove things not needed.
Also, the gain structure is a bit complicated if you want to limit noise to the amp. You are in the digital world, not analog!
If you search, there are some useful applications out there. Best is to take a tried one (not the Wondom examples) and modify them for your needs.
Once you have set things up, you can tune it for your speakers and room. Not very comfortable, but it works.
Sigma Studio is a very mighty tool. Just very easy to do something wrong.
Do not implement too many functions, as the capacity of the Adau is limited, processor power and memory wise. Best to remove things not needed.
Also, the gain structure is a bit complicated if you want to limit noise to the amp. You are in the digital world, not analog!
Thanks a lot, will definitely get back to this comment when I start using it!
I'm interested in this too, for pretty much the same reason as @WASTd... would love to hear how you got on.
I note the recommendations for MiniDSP gear, and yes, if you have the $$$ then why not? However, for the scenario below I'd need 2 x MiniDSP 2x4HD which here in Europe would be 550EUR the pair + some kind of source select/LAN transmission gear. Whereas 2 x ADAU1701 Wondom modules come in under 40EUR. So, erm, yeah.
Anyhow, so ADAU1701 module as a pre-amp... with a little twist... my (probably crazy!) idea:
If you're still reading then you might be thinking, "OK, and how is source selection and gain going to be controlled?" Good point!
We have a Loxone automation system and also use ioBroker for 'fun' add-ons. An example of the latter is that I have a bluetooth remote (it's actually a FireTV remote but any old BT one would do) to control TV and music at the moment. This remote is actually paired with a Raspberry Pi in the comms room and works throughout the house (yes, the house is pretty small). An ioBroker script detects commands from this remote and sends them to the TV or streaming device as appropriate (ioBroker knows which device is currently powered on/playing so knows what to do). This might sound odd, but it works really well - there is zero delay using this Bluetooth remote going through ioBroker - responsiveness is indistinguishable from the one that came with the TV.
The upshot of this is that any ADAU1701 device that gets implemented can be controlled in the same way. Volume & source selection at least which is what I'm interested in. From what I can tell you would control these things by writing to ADAU1701 registers over SPI or I2C and would use a micro-controller (or Raspberry pi) to do this.
Any thoughts on this? Should work, right? How hard could it be?
*I do work in IT and tinker with micro-controllers and such 'just for fun' so connecting this up and programming it doesn't worry me TBH.
I note the recommendations for MiniDSP gear, and yes, if you have the $$$ then why not? However, for the scenario below I'd need 2 x MiniDSP 2x4HD which here in Europe would be 550EUR the pair + some kind of source select/LAN transmission gear. Whereas 2 x ADAU1701 Wondom modules come in under 40EUR. So, erm, yeah.
Anyhow, so ADAU1701 module as a pre-amp... with a little twist... my (probably crazy!) idea:
- In the lounge we have a TV & streaming device, both with digital out.
- Convert both of these digital sources to I2S (toslink/coax -> I2S boards are 20-30EUR) as that's what the ADAU1701 takes as an input and I2S can also easily be transmitted over Cat7 LAN cabling (see later).
- Feed these I2S signals into an ADAU1701 module which will select one & attenuate (or you could even mix them) and send to a 2.1 system in that room. The ADAU1701 can handle bass management or leave it to an external amp. You could use the DACs in the ADAU1701 module or use an external DAC for at least the main stereo channels as I don't read great things about it's DAC - although would be interesting in thoughts on this.
- The above handles source select/volume in the lounge. We also have 2 pairs of ceiling speakers elsewhere in the house that I'd like the option of sending at least the streaming device output to. These ceiling speakers are driven by amps in a comms room so:
- Send I2S signal to comms room over Cat7 cable (spare cable already in place) and feed into a second ADAU1701. This could be signal after selection/mixing (but before attenuation) from the first ADAU1701 or even (and please correct me if wrong) both I2S signals as I believe you only need 4 conductors for one I2S signal and as there are 4 pairs in a Cat7 cable both 'raw' I2C input signals could be transmitted if necessary.
- Second ADAU1701 can output 4 analog channels (2 stereo pairs) for the 2 pairs of ceiling speakers, muted/attenuated as necessary. With the caveat about the ADAU1701 DACs above, surely they are good enough for ceiling speakers that are only for 'background' listening?
- A 'bonus feature': as the second ADAU1701 is driving ceiling speakers believe it's likely they could benefit from some EQ. Their sound is currently far from ideal but good enough for 'background' listening, but that said anything that could improve this would be welcome.
If you're still reading then you might be thinking, "OK, and how is source selection and gain going to be controlled?" Good point!
We have a Loxone automation system and also use ioBroker for 'fun' add-ons. An example of the latter is that I have a bluetooth remote (it's actually a FireTV remote but any old BT one would do) to control TV and music at the moment. This remote is actually paired with a Raspberry Pi in the comms room and works throughout the house (yes, the house is pretty small). An ioBroker script detects commands from this remote and sends them to the TV or streaming device as appropriate (ioBroker knows which device is currently powered on/playing so knows what to do). This might sound odd, but it works really well - there is zero delay using this Bluetooth remote going through ioBroker - responsiveness is indistinguishable from the one that came with the TV.
The upshot of this is that any ADAU1701 device that gets implemented can be controlled in the same way. Volume & source selection at least which is what I'm interested in. From what I can tell you would control these things by writing to ADAU1701 registers over SPI or I2C and would use a micro-controller (or Raspberry pi) to do this.
Any thoughts on this? Should work, right? How hard could it be?
*I do work in IT and tinker with micro-controllers and such 'just for fun' so connecting this up and programming it doesn't worry me TBH.
See this thread (LINK) about the potential problems using the 1701 and I2S signals. The 1701 has to be the master clock source and your SPDIF to I2S board has to operate as a slave. This typically means the 1701 MCLK has to be routed to the slave device as an input. And two 1701 boards should use one common MCLK when using I2S. So you would have to remove the crystal from one board and route the MCLK from one board to the other. This constraint is specified in the 1701 datasheet in the "SERIAL DATA INPUT/OUTPUT PORTS" section:
"The serial data clocks need to be synchronous with the ADAU1701 master clock input."
and
"If an external ADC is connected as a slave to the ADAU1701, use both the input and output port clocks. The OUTPUT_LRCLK (MP10) and OUTPUT_BCLK (MP11) pins must be set to master mode and connected externally to the INPUT_LRCLK (MP4) and INPUT_BCLK (MP5) pins as well as to the external ADC clock input pins. The data is output from the external ADC into the SigmaDSP on one of the four SDATA_INx pins (MP0 to MP3)."
One solution is to use a 1452 board like THIS. The 1452 has built in ASRCs and the linked board has both optical and coax inputs. You will need external DACs. Best of luck!
"The serial data clocks need to be synchronous with the ADAU1701 master clock input."
and
"If an external ADC is connected as a slave to the ADAU1701, use both the input and output port clocks. The OUTPUT_LRCLK (MP10) and OUTPUT_BCLK (MP11) pins must be set to master mode and connected externally to the INPUT_LRCLK (MP4) and INPUT_BCLK (MP5) pins as well as to the external ADC clock input pins. The data is output from the external ADC into the SigmaDSP on one of the four SDATA_INx pins (MP0 to MP3)."
One solution is to use a 1452 board like THIS. The 1452 has built in ASRCs and the linked board has both optical and coax inputs. You will need external DACs. Best of luck!
Thanks for that info, the 1452 board looks interesting as do other variants on AliExpress (1463/1467/1466). Will do more digging on them.
FWIW, I already saw the Wondom 4 in 8 out tutorial (on YouTube) using 2 x ADAU1701: one as master & one as slave (remove crystal, etc). Guessing one could slave them both to an SPDIF converter with master clock or as you suggest, make the SPDIF slave. I note the Wondom WM8804 transceiver can operate in either mode so doesn't appear to be an issue.
FWIW, I already saw the Wondom 4 in 8 out tutorial (on YouTube) using 2 x ADAU1701: one as master & one as slave (remove crystal, etc). Guessing one could slave them both to an SPDIF converter with master clock or as you suggest, make the SPDIF slave. I note the Wondom WM8804 transceiver can operate in either mode so doesn't appear to be an issue.
The ADAU1701 can be made a slave, but that forces you to run the DSP core at the external clock rate, and it means you can only have that one master device in the system. The ADAU1452/ADAU1466 is a much better solution for a preamp, because it has 8 ASRC's to accept data at different rates. It's also a much faster chip with more memory, and that can be important for some designs.
If you are using this for ceiling speakers, you might want to consider the 8-channel ADAU1466 board at AliExpress. It has SPDIF and I2S input, Bluetooth and analog input (PCM1808) and 8 20W power amps. There is an "in-progress" design using this board at this site: http://www.audiodevelopers.com/return-of-the-marthas/
If you are using this for ceiling speakers, you might want to consider the 8-channel ADAU1466 board at AliExpress. It has SPDIF and I2S input, Bluetooth and analog input (PCM1808) and 8 20W power amps. There is an "in-progress" design using this board at this site: http://www.audiodevelopers.com/return-of-the-marthas/
In the scenario I described, why would that be a bad thing?
Thanks, but not really. Don't need amps or that many channels. Moreover:
I did look for DSP boards on AliExpress (from those other than Sure Electronics/Wondom) but couldn't find any with even cursory documentation. I mean, it's not like the Wondom modules mentioned by the OP look to have extensive documentation but there do seem to be enough examples one could follow to achieve my goal.
The other thing about the Wondom ADAU1701 modules are they very economical. Sure, not super powerful, but surely enough for the scenario I described above and the OP's 'preamp' needs?
The ADAU1701 has plenty of power unless you start using some of the ADI algorithms such as Super Bass or Dynamic Bass. Those algorithms use a lot of program memory, and I ran out of instructions when I used them. But for many applications, the ADAU1701 is plenty powerful. Also, the specs on the CODECs aren't as good as "premium" devices, but the CODECs are fine for many high-quality applications.
The biggest limitation of the ADAU1701 for preamp applications is the lack of a sample rate converter (ASRC). Your scenario has two digital devices (TV and streamer), each transmitting using their own clocks (they are "clock masters"). SPDIF receivers will be needed to recover those clocks. You could use one recovered clock as the master clock for the ADAU1701, but the other source will not be synchronized, and it won't work. You could add a simple ASRC board as referenced in this thread, but the cost starts to creep up. Obviously, you could add an optical switcher on the front end, but switching the master clock to the ADAU1701 while it is running might cause problems.
You are correct in pointing out that the DSP boards on AliExpress are poorly documented, but if you ask, they will send you the SigmaStudio design that is pre-loaded in the board. That design has a lot of information that you can use to figure out how the board is wired.
Also, it is helpful to get a board that has the USBi connector on it. I've done a lot of designs with the ADAU1701 without using the USBi programmer, but it takes a good bit of work to develop the microcontroller code to use the ADAU1701 without the USBi programmer. I finally broke down and bought a USBi board for the ADAU1466, because it is too hard to program the EEPROM for that chip without it. But even for the ADAU1701, it is a worthwhile investment.
The biggest limitation of the ADAU1701 for preamp applications is the lack of a sample rate converter (ASRC). Your scenario has two digital devices (TV and streamer), each transmitting using their own clocks (they are "clock masters"). SPDIF receivers will be needed to recover those clocks. You could use one recovered clock as the master clock for the ADAU1701, but the other source will not be synchronized, and it won't work. You could add a simple ASRC board as referenced in this thread, but the cost starts to creep up. Obviously, you could add an optical switcher on the front end, but switching the master clock to the ADAU1701 while it is running might cause problems.
You are correct in pointing out that the DSP boards on AliExpress are poorly documented, but if you ask, they will send you the SigmaStudio design that is pre-loaded in the board. That design has a lot of information that you can use to figure out how the board is wired.
Also, it is helpful to get a board that has the USBi connector on it. I've done a lot of designs with the ADAU1701 without using the USBi programmer, but it takes a good bit of work to develop the microcontroller code to use the ADAU1701 without the USBi programmer. I finally broke down and bought a USBi board for the ADAU1466, because it is too hard to program the EEPROM for that chip without it. But even for the ADAU1701, it is a worthwhile investment.
This thread is super helpful - thank you guys.
So using 2 x Wondom ADAU1701 boards, the 'primary' being fed with 2 SPDIF inputs (converted to I2S) isn't going to work due to clocking issues.
If I have understood correctly (and please comment/correct if wrong as clearly it's pretty new to me)...
Seems that in my 'distributed pre-amp' plan an ADAU1466 is required as a 'primary' as it has ASRCs which are necessary for multiple digital sources.
This device has an SPDIF input. I assume to use this all that is required is an optical -> TTL receiver (no decoding - just a board mounted socket that costs practically nothing). Is that correct?
I would need a second optical to I2S board for the second input. As the ADAU1466 has ASRCs one just needs to connect bitclock, wordclock & data from any optical -> I2S converter - is that correct?
Alternatively could have 2 x optical -> TTL inputs and implement a TTL switch to choose one of these signals to send to the ADAU1466 SPDIF input. Wouldn't enable mixing of signals but that isn't a 'must have' feature. I'm guessing one could even use a GPIO from the ADAU1466 to drive the input selection circuit and thus control over I2C/SPI same as other ADAU1466 parameters.
The ADAU1466 SPDIF output could be used to drive an external stereo DAC for lounge speakers. If one wants the ADAU1466 to do bass management (as opposed to leaving it to any amplifier the external DAC would feed) then put a high-pass filter on the SPDIF output (I2S 1 + 2) and create a sub out on a 3rd I2S output fed into a DAC circuit (I2S in -> RCA out).
For the 2 pairs of ceiling speakers I can still use the original idea of a Wondom ADAU1701 board. Run as slave so remove it's clock crystal and send an I2S signal (after selecting/mixing & including master clock) from the ADAU1466. The ADAU1701 simply attenuates signal as required, possibly does a little EQ then uses it's 4 x analog outputs for to drive 2 stereo amps - no outboard DAC required here.
Have I understood that all correctly?
Thanks
So using 2 x Wondom ADAU1701 boards, the 'primary' being fed with 2 SPDIF inputs (converted to I2S) isn't going to work due to clocking issues.
If I have understood correctly (and please comment/correct if wrong as clearly it's pretty new to me)...
Seems that in my 'distributed pre-amp' plan an ADAU1466 is required as a 'primary' as it has ASRCs which are necessary for multiple digital sources.
This device has an SPDIF input. I assume to use this all that is required is an optical -> TTL receiver (no decoding - just a board mounted socket that costs practically nothing). Is that correct?
I would need a second optical to I2S board for the second input. As the ADAU1466 has ASRCs one just needs to connect bitclock, wordclock & data from any optical -> I2S converter - is that correct?
Alternatively could have 2 x optical -> TTL inputs and implement a TTL switch to choose one of these signals to send to the ADAU1466 SPDIF input. Wouldn't enable mixing of signals but that isn't a 'must have' feature. I'm guessing one could even use a GPIO from the ADAU1466 to drive the input selection circuit and thus control over I2C/SPI same as other ADAU1466 parameters.
The ADAU1466 SPDIF output could be used to drive an external stereo DAC for lounge speakers. If one wants the ADAU1466 to do bass management (as opposed to leaving it to any amplifier the external DAC would feed) then put a high-pass filter on the SPDIF output (I2S 1 + 2) and create a sub out on a 3rd I2S output fed into a DAC circuit (I2S in -> RCA out).
For the 2 pairs of ceiling speakers I can still use the original idea of a Wondom ADAU1701 board. Run as slave so remove it's clock crystal and send an I2S signal (after selecting/mixing & including master clock) from the ADAU1466. The ADAU1701 simply attenuates signal as required, possibly does a little EQ then uses it's 4 x analog outputs for to drive 2 stereo amps - no outboard DAC required here.
Have I understood that all correctly?
Thanks
This looks right, but you could make it a bit simpler by just using a stereo DAC instead of the ADAU1701 board, since all of that processing could be done in the ADAU1466. As you point out, you will need two TOSLINK receivers plus one additional SPDIF--> I2S converter to complement the one in the ADAU1466, plus a TOSLINK transmitter if you need SPDIF output.
You might want to model the design in SigmaStudio to get a better feel for how the serial I/O works with the ASRC's. The EVAL-ADAU1466Z User Guide (see attached) walks through an example using SPDIF input/output and setting up the ASRC's.
You might want to model the design in SigmaStudio to get a better feel for how the serial I/O works with the ASRC's. The EVAL-ADAU1466Z User Guide (see attached) walks through an example using SPDIF input/output and setting up the ASRC's.
Ah yes, of course. Forgetting the 4 x I2S outputs on the ADAU1466 are stereo pairs
1 x I2S = Stereo output for lounge 2.1 system.
1 x I2S = Future use for sub output for lounge 2.1 system.
2 x I2S outputs (after attenuation & possibly EQ) sent over Cat7 to comms room into DACs for ceiling speakers.
Think I'll order one of those MediaWorx ADAU1466 boards & a USB programmer from AliExpress to experiment with. If anyone has any recommended sellers or other sources (shipping to Europe) would be happy to hear.
FWIW, found this similar-ish project using that board: https://andrewshirley.tech/amp-to-speakers-dsp/
If you want to provide some additional channels for future expansion, you might want to look at the ADAU1467 boards from the same vendor (MediaWorx). Both the ADAU1466 and ADAU1467 are 48-channel devices, but you can only take advantage of those channels on the ADAU1466 if you use TDM I/O mode rather than I2S. The ADAU1467 provides 8 extra I/O pins so you can direct some of those channels to those extra pins while still using 4 I2S outputs. The ADAU1467 board is about the same price as the ADAU1466 ($1 difference from one of the vendors), and those extra pins may come in handy someday...
Valid point if one can get those extra IO pins (I assume you are talking about SDATAIO0-7) for $1. I can't find a price difference quite that small, but not much more so yes, maybe still worth it.
Whilst looking I did find several vendors selling ADAU1463 boards of a different format. Eg: https://www.aliexpress.com/item/1005003737571410.html
Looks like a slightly friendlier board to experiment with, although annoyingly they don't mention if it's the 300 or 150MHz version of the ADAU1463. Either way I guess it would be plenty for my purposes. Bearing in mind we are now talking about a single DSP with only 2 channel input and up to 8 channel output (say a channel for each of the 4 ceiling speakers plus 2 channels for 2.1 mains and 2 possibly channels for future subs).
And as you mention TDM... ... the ceiling speakers with their amps in our comms room down an I2S Cat7 link... erm... yeah... why not make that a quad channel link and instead of 2 x stereo DACs get a multi-channel board? A cursory glance seems the answer is because multi-channel DACs are hard to find and/or expensive. Or did I miss something?
Whilst looking I did find several vendors selling ADAU1463 boards of a different format. Eg: https://www.aliexpress.com/item/1005003737571410.html
Looks like a slightly friendlier board to experiment with, although annoyingly they don't mention if it's the 300 or 150MHz version of the ADAU1463. Either way I guess it would be plenty for my purposes. Bearing in mind we are now talking about a single DSP with only 2 channel input and up to 8 channel output (say a channel for each of the 4 ceiling speakers plus 2 channels for 2.1 mains and 2 possibly channels for future subs).
And as you mention TDM...
... the ceiling speakers with their amps in our comms room down an I2S Cat7 link... erm... yeah... why not make that a quad channel link and instead of 2 x stereo DACs get a multi-channel board? A cursory glance seems the answer is because multi-channel DACs are hard to find and/or expensive. Or did I miss something?TDM is tricky because of the data rates and clock skew issues. I2S is around 3MHz, and TDM8 is 25MHz, and it is essentially a parallel bus with separate clock, data and frame sync. It's not good practice to transmit signals like without embedding the clock and using appropriate drivers and receivers.
There are several multichannel DACs with TDM inputs, but not too many hobbyist boards. The one exception is the ADAU1701, which has TDM input and 4 DAC's.
There are several multichannel DACs with TDM inputs, but not too many hobbyist boards. The one exception is the ADAU1701, which has TDM input and 4 DAC's.