TOPIC:

After having a great time implementing DSP solutions for audio (stereo mode with subwoofers) it occured to me to try similar approaches for multi channel home theater.

The (to me anyway!) obvious way to implement this for high quality sound (lossless format, 7.1 or better) would be a DSP device with an HDMI input. You'd be keeping everything digital until you went to the speaker amplifiers.

After some lengthy searching I haven't been able to find anything like this -- it looks like the common solution involves converting back and forth from digital to analog a couple of times along the line, with a resulting huge cabling requirements (individual lines for each channel from DSP/DAC to the amplifier!) With that approach I can barely imagine the cabling needs if you wanted to bi or tri amp all channels on something like a 7.2 system!

Am I missing something here?

Hello,
you are indeed missing something. There is a device right for your needs (albeit discontinued) from miniDSP, the NanoAVR.
Look here for details, under NanoAVR Series: www.minidsp.com/support/legacy-products

HTH

Thanks, I hadn't noticed that product, which does look like it allows for HDMI input and handling all processing digitally.

But, as you noted its not available any longer -- too bad because it looks like it would have been useful!

So, I'm gathering most people just put up with going from HDMI digital, to analog, back to digital for processing, and finally back to analog! Makes me shudder to think about it.

Unless you were lucky enough to have purchased one of those nanoAVRs while they were still available.

I understand SPDIF can't handle 5.1 or 7.1 (or higher) digital signals, but with multiple miniDSP units in parallel I think you could work something out, if only you could connect them with the HDMI digital signal.

I bet someone could get rich if they offered a device with HDMI input and multiple discrete SPDIF outputs to handle all the resulting channels!

MB

I share your concern. It is even harder to implement room correction for a surround system without AD-DA conversion AND without using HDMI-capable equipment. In case you are interested, this can be done with PC as a source, an old PCI sound card, a DDRC-88D (BNC version) and 6 coaxial cables. That is how my system is built. But it is limited to 6 discrete source channels, compared to 8 provided by HDMI.

By the way, this post might give you some hope: www.minidsp.com/forum/nanoavr-support/16...r-product-page#45860