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Can MC output in 64-bit or is 32-bit the max ?

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ths61:

--- Quote from: Awesome Donkey on October 18, 2021, 03:24:05 am ---What DAC are you using? All the DACs I've used or seen max out with 32-bit bit-depth support.

--- End quote ---

Hi Awesome Donkey,

It is the ALSA PCM Plugins that have the FLOAT64 interfaces that JRMC28 writes to. 

The plugin is specified in JRMC28 as the target output "device", not a specific hardware DAC.  The hardware DAC is specified in camillaDSP's plugin configuration at then end of the signal processing chain, thus should be hidden (twice removed) from JRMC28 and (once removed) from the Alsa_cdsp plugin that JRMC28 is writing to.  Both of the ALSA PCM plugins support FLOAT64 which is not offered in the pulldown menu.

I am trying to combine JRMC28's 64-bit volume control with the plugins' 64-bit processing without "thunking" (old Windows term) down to 32-bit in the middle of the signal processing chain.  All of the FIR filters are built in 64-bit.

It appears JRMC28 is using a pre-canned list of menu options because they do not reflect the differences (as shown in alsacap's list) in the various audio cards that I have tried (Gigabyte's onboard sound, W4S DAC2-DSDSE, W4S µDAC, Khadas Tone Board DAC and Okto Research DAC8).

Does the JRMC2X Linux code query and try to use the plugin's published feature set (i.e. in the "AUTO" setting) ?

Thanks much.

ths61:

--- Quote from: JimH on October 17, 2021, 07:49:30 am ---....  MC will output whatever the device and its driver support.

--- End quote ---

Update:
All 6 of the ALSA plugin's published formats are found by the open source aplay test(/dev/zero) CLI dump command. 
Being open source, the code is readily available on how to query an ALSA plugin's feature set.

aplay -v -D camilladsp /dev/zero --dump-hw-params
Playing raw data '/dev/zero' : Unsigned 8 bit, Rate 8000 Hz, Mono
HW Params of device "camilladsp":
--------------------
ACCESS:  MMAP_INTERLEAVED MMAP_NONINTERLEAVED MMAP_COMPLEX RW_INTERLEAVED RW_NONINTERLEAVED
FORMAT:  S16_LE S24_LE S32_LE FLOAT_LE FLOAT64_LE S24_3LE
SUBFORMAT:  STD
SAMPLE_BITS: [16 64]
FRAME_BITS: [128 512]
CHANNELS: 8
RATE: [44100 384000]
PERIOD_TIME: [625 23220)
PERIOD_SIZE: [240 1024]
PERIOD_BYTES: [15360 16384]
PERIODS: [2 8]
BUFFER_TIME: [1250 185760)
BUFFER_SIZE: [480 8192]
BUFFER_BYTES: [30720 131072]
TICK_TIME: ALL
--------------------
Available formats:
- S16_LE
- S24_LE
- S32_LE
- FLOAT_LE
- FLOAT64_LE
- S24_3LE

bob:
Added these formats to MC29.

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