I came across a project in Sigma Studio in which they simulate the operation of a tube amplifier. What attracted me to this project was the ability to control the level of distortion. I made a distortion adjustment using an external potentiometer from 0.005% to 15%.
The result was quite interesting. This project is a good way to test your threshold for sensitivity to distortion.
The design of the project introduces distortions according to this principle:
-When changing frequency, the level of distortion is almost the same for any frequency;
-As the signal level decreases, distortion increases;
-Even harmonics prevail over odd ones.
Project in Sigma Studio.
The result was quite interesting. This project is a good way to test your threshold for sensitivity to distortion.
The design of the project introduces distortions according to this principle:
-When changing frequency, the level of distortion is almost the same for any frequency;
-As the signal level decreases, distortion increases;
-Even harmonics prevail over odd ones.
Project in Sigma Studio.
For those who are interested in the optical input, I posted boards with an optical input on eBay.
Optical input/output
Optical input/output
For some time now I've been working with an ADAU1701 DSP board and separate 2x50w and 1x 100w amplifiers trying to get things to work well together to manage a three way active speaker project. Problems with numerous power supplies, ground loops and general incompatibilities. I was about to re-ignite long lost electronics knowledge and design my own when I saw this post.
I purchased one of the boards and have been working with it for a few weeks now. The unit was delivered on time, well packed, Uriy-ch was in touch throughout, followed up on delivery and has been very helpful with information advice and resolving a few queries on my side.
The amp has been very easy to work with. I'm powering it from a 20V DC power pack to start with as recommended. I reviewed the amp listening on a known set of speakers and was very pleased with the lack of any high frequency hiss which is present on most of the other amplifier boards I have. It has more the enough power for my needs and sound quality is excellent.
Programming has been straightforward, I'm using a Dayton Audio in circuit programmer but any SPI programmer should work fine. The three Sigmastudio projects provided are great starting points. I have settled on the 3 way design but with manual EQ rather than the AutoEQ algorithm which I haven't mastered yet.
I can thoroughly recommend this for integration into DIY speaker projects or as a standalone 2.0 or 2.1 amplifier
I purchased one of the boards and have been working with it for a few weeks now. The unit was delivered on time, well packed, Uriy-ch was in touch throughout, followed up on delivery and has been very helpful with information advice and resolving a few queries on my side.
The amp has been very easy to work with. I'm powering it from a 20V DC power pack to start with as recommended. I reviewed the amp listening on a known set of speakers and was very pleased with the lack of any high frequency hiss which is present on most of the other amplifier boards I have. It has more the enough power for my needs and sound quality is excellent.
Programming has been straightforward, I'm using a Dayton Audio in circuit programmer but any SPI programmer should work fine. The three Sigmastudio projects provided are great starting points. I have settled on the 3 way design but with manual EQ rather than the AutoEQ algorithm which I haven't mastered yet.
I can thoroughly recommend this for integration into DIY speaker projects or as a standalone 2.0 or 2.1 amplifier
For those who don’t like FIR crossover but want to have an even phase, I put together a subtractive crossover in Sigma Studio.
The frequency response and crossover circuit turned out like this.
And this is the measured step response of the sum of three bands.
Below is a project in Sigma Studio.
The frequency response and crossover circuit turned out like this.
And this is the measured step response of the sum of three bands.
Below is a project in Sigma Studio.
I do not plan. There is no space on the board and the microcircuit does not have enough pins.
There are many industrial solutions for cars.
If you use two three-way boards, then you can use the third channel of each board as an output for a subwoofer that can be placed under the table, which will greatly simplify the task of choosing a speaker for a compact active two-way speaker.
Having dug a little into the settings of the adau1452, I realized that the way I had previously used to increase the frequency on the I2S output of the adau1452 is not the optimal way.
It is more optimal to use frequency increase using ASRC; this way eliminates the need to filter the output signal and is generally more rational.
To increase the frequency, I used ASRC2, ASRC3, since ASRC0 and ASRC1 are busy processing the input data stream.
The use of ASRC made it possible to simplify the output part of the project, and the use of ASRC made it possible to use SPDIF transmission from the DSP core at project frequencies of 48 kHz or 96 kHz, which previously could not be done. Also now the board goes into sleep mode more stably when there is no data flow at the input.
Below I have posted basic projects in Sigma Studio configured for different sampling rates within the project using ASRC to increase the frequency on the I2S output.
It should be taken into account that the pin numbering has now changed. Now outputs 4=Ch0, 5=Ch1, 6=Ch16.
It is more optimal to use frequency increase using ASRC; this way eliminates the need to filter the output signal and is generally more rational.
To increase the frequency, I used ASRC2, ASRC3, since ASRC0 and ASRC1 are busy processing the input data stream.
The use of ASRC made it possible to simplify the output part of the project, and the use of ASRC made it possible to use SPDIF transmission from the DSP core at project frequencies of 48 kHz or 96 kHz, which previously could not be done. Also now the board goes into sleep mode more stably when there is no data flow at the input.
Below I have posted basic projects in Sigma Studio configured for different sampling rates within the project using ASRC to increase the frequency on the I2S output.
It should be taken into account that the pin numbering has now changed. Now outputs 4=Ch0, 5=Ch1, 6=Ch16.
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To be honest, setting the project frequency in Sigma Studio is a very non-obvious thing; I had to go through the options for a long time to understand how to correctly specify the settings that will satisfy the project frequency.
Also, those wishing to use the 5V power bus for external devices should take into account that the current that this pole can produce does not exceed 100 mA, it is best to take no more than 50 mA from it.
Also, those wishing to use the 5V power bus for external devices should take into account that the current that this pole can produce does not exceed 100 mA, it is best to take no more than 50 mA from it.