PC controlled full digital plate amp

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Hi,

MiniDSP devices have really quite small processing power, and can only do very basic signal processing. I can not use them as relpacements for Ultimate equalizer DSP processing power.

So this solution is not for me - sorry.

Best Regards,
Bohdan

Did you see the plate amp?. Just don't use the DSP, and it's still very cheap (eventhough it's not digital to output like Texas instruments TAS5612/14/31B
 
To livingstone,

This is really interesting work, and just what i have been looking for for a while. I use MiniDSP, but the digital amplifier is not very powerfull, and their ICE power plateamp still contains digital to analogue conversion. I don't know why they didn't go for TAS5112B or similar digital PWM amplifier

Yep, it's very very interesting. The only thing: - we need to control volume. Would like to know if it is possible in digital domain without noticeable degradation of the sound?
 
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Did you see the plate amp?. Just don't use the DSP, and it's still very cheap (eventhough it's not digital to output like Texas instruments TAS5612/14/31B


Hi,

Thank you for the pointers.

Interestingly, OpenDRC-DI | MiniDSP and PWR-ICE125 | MiniDSP
use AES/UBE digital inputs for audio, but they use USB only for HW control. This is what I would expect.

Now, the plate amplifier PWR-ICE125 looks interesting. If I was to built 16-channel 5.2HT system, I would need 8 of those amplifiers ($2200).
I would be locked into a particular power distribution, which is not optimal.
For instance, I would feed tweeter from 125W/4ohm amplifier, and then struggle to power subwoofer with adequate power. Finally, you lock yourself into 2-way systems.

The audio quality gains from such struggle would not justify all this efforts. So, the plate amplifier could be an option, but the last one I would consider.

I have been running my linear-phase, 5.2 system for the past 12 months, and the audio quality and ease of use exceeded my expectations. Therefore, I am not looking for band-aid improvements. I am looking for an easy-to-build, well designed AES/EBU option, that would be viable from commercial perspective.

Anyway, I appreciate your help.

Best Regards,
Bohdan
 
Are you looking for at one box 16 channel AES/EBU amplifier DIY kit?

The amps from miniDSP can be linked so you can make any combination and it can be bridged for 450 watt mono. It have ethernet control so you can control multiple plateamps etc. There is a discount if you buy more than one.


Hi,


I am drifting away from the miniDSP option. The problem is, that I also need the reverse conversion: Analogue to AES/EBU.

I found this:
Behringer SRC2496 24-Bit/96 kHz A/D & D/A Converter 248-6382

This is a ($199) Behringer SRC2496 24-Bit/96 kHz A/D & D/A Converter, which allows you to do A -> AES/EBU and AES/EBU -> A at the same time on two channels. This would allow me to fully utilize the RME and Lynx sound cards for input and output.

However, the Mamba converters are a lot cheaper, and the do two-way conversions too.

Thanks for your help.

Best Regards,
Bohdan
 
Yep, it's very very interesting. The only thing: - we need to control volume. Would like to know if it is possible in digital domain without noticeable degradation of the sound?

This is indeed the biggest challange. It is done by the TAS:

"the TAS5508C carries additional precision in the form of overflow bits to permit the value of
intermediate calculations to exceed the input precision without clipping. The TAS5508C advanced digital
audio processor achieves both of these important performance capabilities by using a high-performance
digital audio processing architecture with a 48-bit data path, 28-bit filter coefficients, and a 76-bit
accumulator."
 
This is indeed the biggest challange. It is done by the TAS:

"the TAS5508C carries additional precision in the form of overflow bits to permit the value of
intermediate calculations to exceed the input precision without clipping. The TAS5508C advanced digital
audio processor achieves both of these important performance capabilities by using a high-performance
digital audio processing architecture with a 48-bit data path, 28-bit filter coefficients, and a 76-bit
accumulator."

This is about general DSP. Volume control is about resolution of the final DA conversion. No matter what high resolution it is performed, the samples will inevitably be converted (i.e. truncated, perhaps with dither) down to the native resolution of the DAC. All the precision will be lost anyway...

There is no way to circumvent the DAC bit resolution limit. Plus it is disputable if information in the 23-24th bits ever contribute to the DAC result.
 
I graduated for my bachelor's degree of embedded systems engineering with the FDPA design.

Because of this i finally got around getting the USB to I2S done.
Although the whole hardware and software works, it still has some flaws which needs to be addressed.

The software contains an interactive filter design.
Every bi-quid filter shows like a rectangle on the response chart.
You can simply drag and drop the rectangle and see the change in response in real time.

See attached pictures.

The main aim of this project, was the very small foot print (you only need a HTPC, no external pre-amp, amps cables).
 

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