6 Channel volume control PT2325

For some time I've been interested in building an 8-channel volume controller for my 3-way plus subwoofer active system.

I use the miniDSP 4x10HD for my active crossover which makes use of digital volume control. I've had suspicions of digital volume control in properly maintaining signal resolution and negatively impacting optimum gain structure. Secondly, the miniDSP IR volume adjustment is extremely coarse with 3dB jumps in volume!

diyaudio has numerous DIY implementations using a variety of volume control ICs from various manufacturers.

I recently came across this 8-channel volume controller using the TI PGA4311 IC. I have not seen any mention of this on the forum. I'm considering giving it a try myself. It would cost far more than this and take a considerable amount of learning to build a controller myself.

PGA4311 Audio 8 Way Single ended / 4 Channel Balance Volumn Control Board HiFi-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group
 
The PGA4311 is simply 2 PGA2311s in the same package and is loaded exactly the same as a pair of PGA2311s. My Arduino code is currently
loading 3 PGA2311s. Altering it to run 1 more would be a little more than trivial as I also run the channels independently. It is also using NJW1119A
Bass/mid/treble tone control chips.

Do you work with Arduinos? The code is very similar to C. If you want to try
you can have a copy. If you buy an official Arduino they are around $25. Chinese knock offs (I use them) are between $5 and $10 out the door.

 
The PGA4311 is simply 2 PGA2311s in the same package and is loaded exactly the same as a pair of PGA2311s. My Arduino code is currently
loading 3 PGA2311s. Altering it to run 1 more would be a little more than trivial as I also run the channels independently. It is also using NJW1119A
Bass/mid/treble tone control chips.

Do you work with Arduinos? The code is very similar to C. If you want to try
you can have a copy. If you buy an official Arduino they are around $25. Chinese knock offs (I use them) are between $5 and $10 out the door.


I have not worked with Arduinos. However, I am a developer and it is a platform I'm interested in playing with. What LCD display are you using? What IR/rotary encoder are you using? What interfaces on the Arduino are you employing for each device?

Sorry if this is getting off topic for the thread. Maybe we should start another thread and you can go into detail about your controller.
 
I have not worked with Arduinos. However, I am a developer and it is a platform I'm interested in playing with. What LCD display are you using? What IR/rotary encoder are you using? What interfaces on the Arduino are you employing for each device?

Sorry if this is getting off topic for the thread. Maybe we should start another thread and you can go into detail about your controller.

I took your suggestion and started my first thread called 5.1 channel preamp.

 
Hello


I will oder tomorrow the PCB


What do you think about routing?


Board is 100x100mm and empty space is used for CLC-filter for the amp section.
 

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I just received the PCB. Footprints are all good.




I just wait for the IC socket. I forgot to order it befor. I want to have the possibility to remove it easy.




I have 4 pcbs I can sell for the shipping fee. If some is interessted you can PM me.
 

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I strongly suspect that the reason more DIY hobbyists don't implement embedded MCU based control is due to a lack of specific knowledge about how to code and load the required S/W. The younger folks here are often familiar with how to do that, however, some of the older folks, maybe not so much.

There are finished S/W modules available, such as on the hifiduino site, however, unless you are utilizing the specific system hardware those modules were written for it must be modified to suit. Which requires knowledge of MCU programming. Even should some desired S/W module be utilized unmodified, the hobbyist still requires knowledge of what loading tools are required and how, exactly, to perform and verify the load.

I have to believe that there is probably a good Webinar, or YouTube series of clear, step-by-step, how-to-do-it videos somewhere on basic embedded MCU application S/W development and loading to specific MCU platforms, such as the Arduino. Basically, an 'everything you wanted to know about embedded MCU development and implementation but we're afraid to ask' type of thing. If anyone knows of such an Webinar or videos, please post links here for the benefit of those here who might be interested.
 
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Hi,
I have designed something similar however using electrolytic capacitors on the output stage. I am struggling to figure out the correct value for the current limiting resister connected to pin 4 VCCA and Pin 17 VCCV. I have tried 22 ohms on pin 17 and 100 ohms on pin 4 however there seem to be some issue when I turn on the volume control in between I can see the speaker pop. In addition is it ok to connect the pin 7 (mute) permanently to the ground so that the mute function is disabled. Please help
 

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