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.