Hi Gagan, I assume that you must have a custom CoreAudio driver for this PCIe device? If so, where did you get that? The solution surely lies within that driver.
Brian On Dec 6, 2024, at 6:24 PM, Gagan Sidhu wrote: > hi bw, > > actually my case is a PCI(-E) device driver where there are a maximum of four > streams, each with their own L/R channel that i’d like to add a balancer for. > > it sounds nontrivial though. i guess i shoudln’t be surprised by this. > > i wish there was an example i could use. of any kind, really. > > Thanks, > Gagan > > On Dec 6, 2024, at 7:20 PM, brian wrote: >> I suggest looking at the arrangement of streams, channels, and properties >> for another audio interface where the balance slider appears (and is not >> grayed out). >> >> For general CoreAudio drivers, the channels can be grouped into streams of >> 1, 2, or more channels. I'd be curious whether balance only appears on >> streams with two channels, or if it appears in more configurations. >> >> In your case, it seems you have a USB audio device, so the mapping from USB >> to CoreAudio is determined by the USB Descriptors. Again, looking at some >> other audio interface that support balance should tell you what you need. >> >> Of course, once you find out the configuration that works for other >> interfaces, it may not necessarily be appropriate for your device. >> >> I've seen multichannel interfaces - eight to ten channels - where every >> channel has its own stream (they're all mono streams) or where the channels >> were grouped into an eight-channel stream (for the main outputs) plus a >> two-channel stream (for the headphones). I cannot recall whether balance >> appeared for any of these. >> >> Besides the streams and channels, looks at the properties for those aspects, >> and the values returned for those properties. You might need to use >> something like AUHAL or write your own tool to query everything on an >> interface that supports balance. That's one way to find out what you need. >> Of course, with a USB device, you'll need to know which Descriptors >> correspond to the CoreAudio properties. >> >> Brian Willoughby >> >> >> On Dec 6, 2024, at 5:42 PM, Gagan Sidhu wrote: >>> i thought this would have been taken care of by the API, but i guess i >>> would need to tell it the pins/gpio/whatever about which one is let and >>> right. >>> >>> does anyone have good examples i could work off to add this feature? it >>> doesn’t seem that apple’s documentation or USB audio driver shows how this >>> is done. >>> >>> https://github.com/i3roly/C-Media/issues/3 >>> >>> Thanks, >>> Gagan _______________________________________________ Do not post admin requests to the list. They will be ignored. Coreaudio-api mailing list ([email protected]) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/coreaudio-api/archive%40mail-archive.com This email sent to [email protected]
