Yep. I just started another article on the cell phone app--it is article 14. The article shows the current user interface on the Android app and describes some of what is going on "under the hood". Hoping to finish the article in the next two weeks.
I had set this project aside for a while, but now it is mostly done. Everything described in the article works, except for the A/B switching, which I'll get to before long. Usually these projects never end, but I'm using all of the Program memory in the ADAU1701 and all of the EEPROM in the Arduino CPU, so this project will actually get "done"
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Yep. I just started another article on the cell phone app--it is article 14.....
Amazing work Neil - thanks for creating this resource. Will you be detailing how to connect the bluetooth interface to the board/s? Cheers!
Thanks. The Bluetooth connection is shown in the schematic for the stereo 3-way DSP board in article #6. I'll post the DesignSpark files for the new version of the board once I test it. I've got a box of bare boards, and haven't built up any yet.
The connection is simple: just connect RX of the Bluetooth board to TX of the micro (pin 9), and TX connects to RX (pin 10) of the micro. You also need power and ground. The micro on the teensy has 3 serial ports. I use Serial1 for the Nextion display, Serial2 for Bluetooth and Serial3 for FTDI/USB.
I asked for the default sigmastudio project via youtube comment and Carl was kind enough to oblige!
"http://www.sure-electronics.net/DSP1701_AMP2_Project Source File.rar"
(Yes the link url has underscores and spaces)
"http://www.sure-electronics.net/DSP1701_AMP2_Project Source File.rar"
(Yes the link url has underscores and spaces)
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Awesome, might have to give one of these boards a try. I see Sure also sell a combined amp/dsp board now. Thank again for your work.
I asked for the default sigmastudio project via youtube comment and Carl was kind enough to oblige!
"http://www.sure-electronics.net/DSP1701_AMP2_Project Source File.rar"
(Yes the link url has underscores and spaces)
Thanks for sharing that.
Hello everyone
Within my project I have to create amplified subwoofer (40-200 Hz and max volume 3 L). I know that this is a challenge to reach this parameters, but I would like to discuss just electronics part.
I found JAB3-50 Audio Amplifer with DSP. I am really interesting in this solution, but I need to clarify some practicals aspects of this solution. Since I have limited budget it is very iportant for me to know all aspects, because Sure web site does not provide full info. Also I have contacted to Sure via mail, But I recieved answer from manager (...you know)
So, could you, please, answer and clarify some information:
1) To get 2.1 (I need to connect mu sub to the other passive 2 channel sustem) I need to use JAB2 & JAB3, but in this case does it work like whole system, I mean if I want to use Bluetooth connection will I have output sound from both JAB2 & JAB3 (Bluetooth will work for these two boards). In general, bluetooth connection is good?
2) In case of using input audio via cables (not Bluetooth) where I have to connect my input signal to the JAB2 board? or JAB3? I did not find this information
3) In case of using JAB2 & JAB3, if I understood correctly, DSP on JAB3 provide 4 output channels? So in Sigma Studio can I use 2 channels from JAB2 and 2 from JAB3?
4) Can I use many filters in Sigma studio and what are the limitations for this DSP ( I mean how many filters or types of filters or memory and so on...) ?
How many instructions I can use with ADAU1701?
Because I have ADAU1772 evaluation board (for a test) and inside Sigma studio there are just 32 instructions and limited toolbox for the dsp
And when I use parametric Eq and simple low pass filter I have big level of noise at the output. But when I increase the Sampling frequency up to 192 this noise disappears. I dont understand why? This is a bug of Sigma studio or dsp board? And I am wondering will I have the same with JAB3?
5) If someone had the problem, when this two board are in idling regime (without input signal) there are some noise? Because I have seen some video on YouTube, when this problem was take a place ( YouTube )
6) If I want JAB3 only for subwoofer channel I have to connect two output channels in one channel, in this case all parameters for this 2 channels in sigma studio should be identical? is not it?
7) To provide DSP without Sigma studio, In-Circuit Programmer- ICP1 should be connected all the time to JAB2 & JAB3?
8) If I choose bluetooth regime on ICP1, all DSP settings are disabled?
Because it would be great just to control the volume from the Sure app from smartphone and using self-boot EEPROM. Or this is not possible?
9) What about the problem of 12 MHz crystal. Is the problem fixed? now all boards are 12.228 MHz crystal?
But what is critically to use the board with 12 MHz crystal?
10) Are there any other bugs and is this solution generally good?
What about amplifiers of this board? Are they implemented well? will they work with 2 Ohm load?
Sorry for the big questions.But I really hope for answers and I will be very grateful
Thank you so much!
Within my project I have to create amplified subwoofer (40-200 Hz and max volume 3 L). I know that this is a challenge to reach this parameters, but I would like to discuss just electronics part.
I found JAB3-50 Audio Amplifer with DSP. I am really interesting in this solution, but I need to clarify some practicals aspects of this solution. Since I have limited budget it is very iportant for me to know all aspects, because Sure web site does not provide full info. Also I have contacted to Sure via mail, But I recieved answer from manager (...you know)
So, could you, please, answer and clarify some information:
1) To get 2.1 (I need to connect mu sub to the other passive 2 channel sustem) I need to use JAB2 & JAB3, but in this case does it work like whole system, I mean if I want to use Bluetooth connection will I have output sound from both JAB2 & JAB3 (Bluetooth will work for these two boards). In general, bluetooth connection is good?
2) In case of using input audio via cables (not Bluetooth) where I have to connect my input signal to the JAB2 board? or JAB3? I did not find this information
3) In case of using JAB2 & JAB3, if I understood correctly, DSP on JAB3 provide 4 output channels? So in Sigma Studio can I use 2 channels from JAB2 and 2 from JAB3?
4) Can I use many filters in Sigma studio and what are the limitations for this DSP ( I mean how many filters or types of filters or memory and so on...) ?
How many instructions I can use with ADAU1701?
Because I have ADAU1772 evaluation board (for a test) and inside Sigma studio there are just 32 instructions and limited toolbox for the dsp
And when I use parametric Eq and simple low pass filter I have big level of noise at the output. But when I increase the Sampling frequency up to 192 this noise disappears. I dont understand why? This is a bug of Sigma studio or dsp board? And I am wondering will I have the same with JAB3?
5) If someone had the problem, when this two board are in idling regime (without input signal) there are some noise? Because I have seen some video on YouTube, when this problem was take a place ( YouTube )
6) If I want JAB3 only for subwoofer channel I have to connect two output channels in one channel, in this case all parameters for this 2 channels in sigma studio should be identical? is not it?
7) To provide DSP without Sigma studio, In-Circuit Programmer- ICP1 should be connected all the time to JAB2 & JAB3?
8) If I choose bluetooth regime on ICP1, all DSP settings are disabled?
Because it would be great just to control the volume from the Sure app from smartphone and using self-boot EEPROM. Or this is not possible?
9) What about the problem of 12 MHz crystal. Is the problem fixed? now all boards are 12.228 MHz crystal?
But what is critically to use the board with 12 MHz crystal?
10) Are there any other bugs and is this solution generally good?
What about amplifiers of this board? Are they implemented well? will they work with 2 Ohm load?
Sorry for the big questions.But I really hope for answers and I will be very grateful
Thank you so much!
I can provide some info on that JAB3-50 amp that might answer a few of your questions. My goal was to control it with a teensy3.2 CPU that has both an LCD display and Bluetooth interface. You can control the DSP from either the LCD or Bluetooth using an Android app--just wanted to see how well things worked using either or both.
Things looked promising initially, because I was able to control the DSP with my code and select between different crossovers, control the volume, delay and EQ...and all looked good. The JAB3-50 even routes the extra two DAC outputs to a connector, so these boards could be used for a nice 3-way with an external amp or powered subwoofer. But when I came back to listen again later, it wasn't working anymore...
It turns out the JAB3-50 is "optimized" for battery operation, and that battery operation gets in the way of using a microprocessor to control the DSP. The problem is that the JAB3-50 has its own micro that is mostly there to manage the power consumption and battery charging. The Sure micro isn't connected to the DSP I2C bus, but it can turn off the power to the ADAU1701. The Sure micro (PIC16F1503) monitors the signal using one of the ADC inputs (pin 7)and it shuts off the power to the ADAU1701 (via Q1) after detecting silence for about 30 seconds. When the power is restored, the ADAU1701 resets itself and reloads its code and parameter data from the EEPROM.
That power-down operation gets in the way of controlling the ADAU1701 from an external micro, because on reset any program and parameter data that was written into the DSP gets reset to '0'. Even if you put your own program into the EEPROM, you would need to make sure the parameter data gets restored properly every time the DSP is reset. Arrgh!
I looked for a simple way to keep the micro from shutting down, and there doesn't seem to be one. So I soldered a header to the empty pins next to the micro on the JAB3-50, ordered a PICkit-3 programmer, and set about learning how to program PIC micros--something I did not want to do.
I now have a simple program for the PIC16F1503 that should keep the micro from shutting down the DSP. However, I keep having other problems with power cycling. I've fried two JAB3-50 boards and two teensy3.2 boards, and I believe it is due to the voltages coming up at different times and trying to communicate with the ADAU1701 when it is powered down. I think that problem can be fixed by using the 4.5V output from the JAB3-50 instead of the external power supplies, but I'm starting to feel a bit frustrated.
The bottom line is that there just doesn't seem to be a simple way to control the ADAU1701 on the JAB3-50 from an external micro. You will have to solder on a header and reprogram the PIC micro on the board--something that most people will not want to do. You can put your own code in the EEPROM, but you won't be able to make changes in real-time from a cell phone app or a local display. So I'm not too excited about this product anymore. It looked promising at first, but the design is a dead-end for my needs.
Hello Davis, Thank you for your response. It is really interesting and useful
But I don't need to use external microprocessor for controlling DSP.
I just want to use it in direct way, for its intended purpose
I need to tune up DSP at Sigma studio and then run configured DSP from EEPROM
Thank you
The capabilities of the DSP load I am using are outlined in Article 12 at Audiodevelopers. It's got a 9-band equalizer for room correction, a couple of different bass enhancement algorithms, and some "custom" filters that can be used to tame other room or driver response anomalies. But the bulk of the processing in the DSP configuration I'm using is dedicated to implementing a stereo 3-way crossover, with various slopes and crossover points. One of the crossover options is "none", so you don't need to use the crossover biquads, but if you are willing to write your own SigmaStudio code those crossover biquads could be used for extensive room correction/EQ for full-range drivers.
There is no app or other software to automatically adjust the response, but the ADAU1701 has some built-in tone generation capability that could be used for that application. I haven't tried using those DSP blocks, but it might be fun to try.
I like those Nextion touch screen displays, but overall its cheaper and easier to add a Bluetooth adapter and use a cell phone to control the DSP. The Nextion displays are reasonably priced, but it's difficult mounting them. ITEAD has some 3D printed bezels that make mounting easier, but so far I haven't found an easy way to add them to a speaker. You need to be able to easily remove the LCD display because they get programmed by inserting an SDHC card into the socket on the back of the board. Any time you add a new capability you will need to reprogram the micro on the LCD display, so you need easy access to that SDHC card socket.
I'll post some more pictures of the LCD display with a JAB3-50 amplifier on Audiodevelopers in an upcoming article.
Hi guys, novice here. I got my ADAU1701 with JAB3 working last night. Was pretty easy as there's lots of good info here. Thanks.
After I re-programmed my JAB3 with ADAU1701 (easy test, just adding two volume controls, works fine), I can't use my potentiometers on JAB3 anymore. I read that re-programming is the reason for that, but is there a way to get them back?
Thanks for info, especially Neil, I'm reading your "active speaker articles" with joy
-Sup
After I re-programmed my JAB3 with ADAU1701 (easy test, just adding two volume controls, works fine), I can't use my potentiometers on JAB3 anymore. I read that re-programming is the reason for that, but is there a way to get them back?
Thanks for info, especially Neil, I'm reading your "active speaker articles" with joy
-Sup
Post #144 has a link that includes a JAB3 folder. Open that with SigmaStudio and you should be able to restore the original code.
Thanks for info, especially Neil, I'm reading your "active speaker articles" with joy
-Sup
Glad to hear that
Excellent!
I've looked all Carl's videos and actually found the file from his comments on one tutorial (it had typos, but I fixed them and dl'ed the file yesterday...and had absolutely no idea what it was, but looking at it now)
But I have a questions (any info appreciated as usual):
What I'm doing at the moment is that I have ICP1 connected to PC's USB and programmer cable between ICP1 and JAB3. I have extension cable for 3.5mm input and have my mobile connectec to it, which plays premium Spotify.
1. When I was playing music from PC's SB X-Fi with 3.5mm, I have loud background noise when USB was connected to ICP1. Is this "galvanic connection"-noise?
2. After reading few different ways (forums/Carl) of compiling and downloading code to JAB3, I'm bit puzzled. When I have all pieces connected (JAB3, ICP1 via USB), I can simply compile code and download it. There's a few sec pause on the music, but then JAB3 wakes up and I can turn knobs and try swicthes. What am I missing here? Carl's video tells me to have "tweezers to shortcut JAB3" and "press reset after download". Other tells me to turn switch on ICP1 from 1 to 2 and after download turn back to 1. Mine works without those?
3. If I press reset on JAB3, it doesn't have sound until I disconnect ICP1. Is this normal?
4. Not sure about this...I have simple schema, where I have two speakers connected to JAB3. When I create a code which has dynamic bass or loudness etc to increase bass, the bass gets stronger only if I lower sample rate frequency. When it's default 48.1, sound it pretty flat. By changing rate to 32 (and propagate) , bass gets lot stronger. I got this tip from other forum (?), but can't explain this.
EDIT: This is the tip (it's about ADAU1701):
dsp - Lack of bass with higher sampling rates - Electrical Engineering Stack Exchange
This is my first touch to DSP and I love this! Next thing is trying out BT-module for JAB3 and play with JAB2+extensions....
Cheers,
Sup
I've looked all Carl's videos and actually found the file from his comments on one tutorial (it had typos, but I fixed them and dl'ed the file yesterday...and had absolutely no idea what it was, but looking at it now)
But I have a questions (any info appreciated as usual):
What I'm doing at the moment is that I have ICP1 connected to PC's USB and programmer cable between ICP1 and JAB3. I have extension cable for 3.5mm input and have my mobile connectec to it, which plays premium Spotify.
1. When I was playing music from PC's SB X-Fi with 3.5mm, I have loud background noise when USB was connected to ICP1. Is this "galvanic connection"-noise?
2. After reading few different ways (forums/Carl) of compiling and downloading code to JAB3, I'm bit puzzled. When I have all pieces connected (JAB3, ICP1 via USB), I can simply compile code and download it. There's a few sec pause on the music, but then JAB3 wakes up and I can turn knobs and try swicthes. What am I missing here? Carl's video tells me to have "tweezers to shortcut JAB3" and "press reset after download". Other tells me to turn switch on ICP1 from 1 to 2 and after download turn back to 1. Mine works without those?
3. If I press reset on JAB3, it doesn't have sound until I disconnect ICP1. Is this normal?
4. Not sure about this...I have simple schema, where I have two speakers connected to JAB3. When I create a code which has dynamic bass or loudness etc to increase bass, the bass gets stronger only if I lower sample rate frequency. When it's default 48.1, sound it pretty flat. By changing rate to 32 (and propagate) , bass gets lot stronger. I got this tip from other forum (?), but can't explain this.
EDIT: This is the tip (it's about ADAU1701):
dsp - Lack of bass with higher sampling rates - Electrical Engineering Stack Exchange
This is my first touch to DSP and I love this!
Next thing is trying out BT-module for JAB3 and play with JAB2+extensions....Cheers,
Sup
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Hi Sorokin
Im in the same situation.
That is; whising I knew the answers, especially to your questions 1,2 and 3, did you find out ?
alternatively or maybe even better can I use all 4 ports on the Sure AA-AP23122 (no amp on board) with 4 external amps ?
A new quastion: will the problems regarding using the I2S digital input be any easyer if I strictly only want input (no output) ?
Im in the same situation.
That is; whising I knew the answers, especially to your questions 1,2 and 3, did you find out ?
alternatively or maybe even better can I use all 4 ports on the Sure AA-AP23122 (no amp on board) with 4 external amps ?
A new quastion: will the problems regarding using the I2S digital input be any easyer if I strictly only want input (no output) ?
Anyone else having trouble accessing the Sure Electronics site?
I try to go to sure-electronics.net/download and all I get is random characters.
I try to go to sure-electronics.net/download and all I get is random characters.
I was after the product sheet for a TDA2050 amp, product AK31161. I printed a copy when I built it but want to compare their schematic with the datasheet.
I found an active file directory, Index of /rf,audio, but nothing for the ADAU1701 there and only the datasheet for my AK31161.
No response from Sure through their website or their ebay account so don't know what the go is.