Hello everyone, let me know if I'm getting over myself here as I'm looking for car audio performance with DIY prices
I am wanting to build a 6-8 channel DSP which have DACs that can provide 6-8Vrms single-ended outputs. Ideally, I would like to have a USB into the DSP as the signal source, and then DACs that can sufficiently match car audio amplifier's gain. I have found the PCM5102A chips that have 2.1Vrms, which would suffice, but I'm striving for car audio relatability. Worst case, I find a used car DSP with what I'm looking for that suites my needs but that's not DIY.
Right now, I am thinking of using an USB to I2S into a Wondom ADAU1701 module for processing, then 3 or 4 PCM5102A boards for I2S DAC, and then a 5x times multiplier on each DAC? I would remove the crystal oscillator for the USB to be master board.
Let me know if I'm trying way to hard or if you have any other recommendations that I could try out
thank you
I am wanting to build a 6-8 channel DSP which have DACs that can provide 6-8Vrms single-ended outputs. Ideally, I would like to have a USB into the DSP as the signal source, and then DACs that can sufficiently match car audio amplifier's gain. I have found the PCM5102A chips that have 2.1Vrms, which would suffice, but I'm striving for car audio relatability. Worst case, I find a used car DSP with what I'm looking for that suites my needs but that's not DIY.
Right now, I am thinking of using an USB to I2S into a Wondom ADAU1701 module for processing, then 3 or 4 PCM5102A boards for I2S DAC, and then a 5x times multiplier on each DAC? I would remove the crystal oscillator for the USB to be master board.
Let me know if I'm trying way to hard or if you have any other recommendations that I could try out
thank you
Looks like you'd need something like FreeDSP (aurora or octavia).
Do you want to do the processing on DSP or something like Raspberry Pi and CamillaDSP?
Do you want to do the processing on DSP or something like Raspberry Pi and CamillaDSP?
Yes, I would like to do the processing on the DSP but I'm not limited to it. I want a dsp that would be as similar as to car use as possible but on the bench top.
I've shilled this DSP more than a few times, but I really do like it...
https://www.aliexpress.us/item/3256806414564436.html?
Choose either the "PCM1798 car engine" or "ES9028 car engine". It can do 12Vrms output balanced, so 6Vrms if you use it single-ended. It has 1/4" TRS outputs, so you will need to make up your own cables/adapters for RCA. All 1/4" TRS to RCA adapters I can find short the negative output to ground (bad).
It has USB input, but if you use it with Android the volume will be reduced. I think that can be fixed with something like UAPP.
It's probably the easiest, cheapest, all-in-one solution.
https://www.aliexpress.us/item/3256806414564436.html?
Choose either the "PCM1798 car engine" or "ES9028 car engine". It can do 12Vrms output balanced, so 6Vrms if you use it single-ended. It has 1/4" TRS outputs, so you will need to make up your own cables/adapters for RCA. All 1/4" TRS to RCA adapters I can find short the negative output to ground (bad).
It has USB input, but if you use it with Android the volume will be reduced. I think that can be fixed with something like UAPP.
It's probably the easiest, cheapest, all-in-one solution.
I would like to use a computer as my USB source into the DSP. Use REW or some other software to measure car amplifiers. I forgot to mention that I want to use the Cosmos ADC back into the computer for measurements.
If you aren't going to actually use it in a car, get an AC input version then I guess.
Here's the software for the DSP if you want to see how you like it first...
I also suggest removing the channel 1 ADC card if you get one. It's active with the USB soundcard, so the low level noise from the ADC is present when using USB. Use channel 2 for analog inputs.
Then if you go for ADAU option I can suggest using York USB->I2S interface because then you can use one USB port to stream audio and program the DSP. I'll send a PM.
I don't know what output power you need for the speakers, but if you need power up to 100W, you can abandon the analog signal and use a power DAC.
In general, think about the applicability of a power DAC with DSP in your system.
https://www.diyaudio.com/community/threads/3-way-dsp-amp.415065/#post-7734938
I want to test daily driver car amplifiers. Probably no more than 2000 watts mono and 4x150 for full range. Nothing like YouTube stars. Just want to provide the amps full signal voltage to clipping with low noise and gain match properly. I do want full digital signal to DSP and isolated power
To give an example, my personal amps going into my Jetta are an Alpine R-A90S, which has an input sensitivity up to 4.0V, and an Orion XTR2500.1dz, which has an input up to 6.0V. Sidenote* I plan to run both amps only at 4 ohm for daily driving. Some newer amps can go up 8.0V input.
Purely curiosity. Apply different filtering and see how the amps respond. Visualize how can I push the amps without dirtying up the signal. I would probably use it also for measuring speaker builds as starting points for passive crossover designs. There's a myriad of things I can do with home and car audio with this DSP build. I think REW would use the DSP as a reference for measuring THD+N on amplifiers.
As I understand, the source of the test signal will be a computer? If so, why do you need a DSP? You can install a program on the computer that will perform all the functions of the DSP, you will only need to find a sound card that can give you up to 6V at the output.
https://equalizerapo.com/download.html
https://equalizerapo.com/download.html
I was just thinking of the same signal path as I would use in a car; HU with digital coaxial out -> dsp -> amps. I thought I would go computer -> DSP -> amp -> ADC/computer.
I'm not just testing the amps for my car. I want to test others in house and don't want to pull my car dsp out (Alpine DSP only does 8Vpp and don't want to buy a new one). It's merely for testing purposes but some leisure to mess around with drivers. Like what members of Distortion Factory are doing in the Facebook group.