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TAS5634EVM: Not able to play audio with samplerates >48kHz from any source

Part Number: TAS5634EVM
Other Parts Discussed in Thread: TAS5558, , PUREPATHCONSOLE, TAS5548, DIX4192, TAS5634

Hello,

I have the TAS5634EVM and want to evaluate especially the capabilities of TAS5558.
One important point is to test support of samplerates of input audio in range of 44.1kHz to 192kHz.

I am able to play audio from the sources USB, SPDIF-Coax and SPDIF-Toslink. But I fail to play samplerates other than 44.1kHz or 48kHz.

I use PurePathConsole v1.16. Target is TAS5548/58. OS is Windows 11.

EVM FWID is FWIDPCM5548EVM-B (according to PurePathConsole v1.16)

EMVFirmware version is 354 (according to PurePathConsole v1.16)

This is what I tried:

1. When I select USB audio I am not able to change sample rate to anything else than 44.1kHz. Windows doesn't provide any other option. So regardless what content I play, always audio with 44.1kHz is in use.
The Jumper J6 is properly selected to USB.
When I check the used LRCK frequency at test point close to J12 I always see 44.1kHz.

-> It seems that TAS1020B used on this EVM is limited to 44.1kHz only. But maybe this this is a config problem of TAS1020B (which is most propably configured by the MCU on EVM) or a driver issue.

Is this EVM supposed to support other samplerate than 44.1kHz from USB input? If yes, how could I make use of such higher samplerates.

2. I also checked the SPDIF-Coax and SPDIF-TOSLINK input. All jumpers and switches are set properly. I selected the proper input via the INPUT button and followed exactly the procedure from manal.
This is my test result:

- Audio with 44.1kHz, 88.2kHz: I hear the audio, but samplerate at test pint near J12 is always 44.1kHz (so even when I play 88.2kHz)
- Audio with 48kHz, 96kHz: I hear the audio, but samplerate at test pint near J12 is always 48kHz (so even when I play 96kHz)
- Audio with 176.4kHz: I hear no audio, samplerate at test pint near J12 is 44.1kHz. I checked test point SDN, which is permanently low.
- Audio with 192kHz: I hear no audio, samplerate at test pint near J12 is 48kHz. I checked test point SDN, which is permanently low.
I doublechecked the SPDIF signals with another device. The samplerate and data is as expected.

So I face two issues when using SPDIF input:
A: DIX4192 seems to output I2S data only in samplerate 44.1kHz or 48kHz
B: DIX4192 fails to process samplerates 176.4kHz and 192kHt from DIR
-> My guess is that this is some invalid config of DIX4192 by the MCU. Maybe the routing of clocks is not correct and instead of using the clocks from DIR, always reference clocks are used.

Could you please help me to test TAS5558 with audio using samplerates > 48kHz with this EVM?

  • Hi Andreas

        I'm sorry the USB or SPIDF port on the EVM don't support to output all kinds of sample rate. If you want to test with different sample rate of TAS5634, it is suggested to send in I2S signal directly to the input pins of our device TAS5634.

  • Meanwhile I set up to use the I²S input in order to play other samplerates, which works. But this unfortunately limits the use of the EVM as I need another PCB to provide that data. A bit of a pitty. Especially as it seems to be no hardware, but MCU FW limitation.

    When trying to test 192kHz samplerate (input signal as well as internal processing in TAS5558), I stepped over another issue. In the "TAS554/58 Proces Flow" tab of PurePathConsole1, there is a drop down selector for smaplerate. Here I can select 96, 176.4 and 192kHz. Actually it is not really clear what this parameter does. One visibal thing is that the audio bandwith for the biquad frequency response plots are adopted. But it seems that TAS5558 config is not fully adopted. When I set to "192kHz" (whatever it does), play 192kHz input and have a biquad set (for example a highpass), I can see that the actual filter applied is not at the frequency as shown in config tool. But at half frequency. I figured out that actally TAS5558 doesn't run in 192kHz mode. Register 0xC5 is not set up properly. When I manually change register 0xC5, biquad works as expected.

    Could you please help me on 2 things?
    1. What is actually the usage of this sample rate parameter in PurePathConsole1 for TAS5558?
    2. Is there a manual that describes all the details "TAS5548/58" target of PurePathConsole1

    Thanks a lot for your support.

  • Hi Andreas

       

    What is actually the usage of this sample rate parameter in PurePathConsole1 for TAS5558?

      The PPC software will use Sample rate to calculate the correct BQ parameter. If the Sample rate value you choose is different with you real using, the BQ won't be correct. You could find it from frequency response curve.

    Is there a manual that describes all the details "TAS5548/58" target of PurePathConsole1

      I'm sorry there's very limited resource for old devices. Please check if below document is useful for you.

    https://software-dl.ti.com/secure/software/asc_purepath/Audio/PUREPATHCONSOLE/X_Purepath_Console_1/PurePathConsole_Quick_Start_Users_Guide.pdf?__gda__=1674541858_1aa389ee717aea569764d63a190adbda