Connecting a Mac mini to RSP 1570

[RoMan]

Hi all,

I have connected my mac mini to hdmi 2 on my Rotel 1570. Problem is the Rotel is reading Multichannel but I'm only receiving 2 channels of audio. I have configured to 7.1 in the Audio MIDI Device setting in the Mac and it should not have an issue reading the discs as I have heard the mac mini can support up to 8 channels of audio via hdmi as well it has 5.1 capability to decode Dolby surround so I'm not sure why I can't get surround sound all the way around. :cry:

What is going on here? Is it the Rotel or is it the mini mac? I have updated the software of the mini mac to the latest version. So I'm stumped to know why hdmi to hdmi the signal is not being recognized since Dolby licensed this to Apple. My rotel should be able to recognize a digital signal from hdmi.

Thanks in advance everyone. I really appreciate your assistance with this.

RoMan. :T

[hurin]

I had the same problem on my PC, if the computer decodes the signal to PCM it is apparently only possible to pass two channels, even if HDMI has more than enough bandwith.
To solve it you need to pass the undecoded signal to the Rotel, go into the settings of the program you use for playback and select SPDIF.

If you're using VLC there is a screen that looks like this, select 'Use S/PDIF when available'.

[mjb]

Apple supports 8 channel 24-bit audio at 192kHz, Dolby Surround 5.1 and stereo output.

http://support.apple.com/kb/HT4214

You should see (and select) the Rotel 1570 in the Sound Output pref pane.

[RoMan]

Thanks fellas.


Mjb- you are right I do see it as ROTEL AVR and have selected it in the MIDI Audio Device. The display on the preamp says Multichannel. When I try to change it I can only choose between Multichannel and Multichannel downmix(which is essentially FL, FR, SW). So if the mac recognizes as ROTEL AVR then my question is why am I not getting all speakers to play even as Multichannel. I have selected in the mac Multichannel and configured it.

Hurin- its possible that there may be a conversion to PCM happening which could explain why I'm getting 2 channel stereo . When I use the SPDIF digital audio out on the mac via a toslink adaptor and select a digital input on the Rotel I get PCM 2ch, Dolby Pro Logic, Dolby 3 Stereo and I believe Dolby D 2ch(on a dvd I played last night). I can't get Dolby Pro Logic IIx in which I understand takes a 2 ch source and plays it through all the speakers.

I want to use the HDMI setting as it shows that it can output up to 8 channels of audio which is what I want to run provided I can get it working. So I'm not really sure if its a hardware thing with the mac or is it with the Rotel.

Thanks again.

RoMan :T

[hurin]

I'm afraid you misunderstood me. I was not talking about the connection itself. The problem is not if you use HDMI or Toslink, its that if you let the computer decode the signal you get stuck with 2 channel PCM.

Selecting SPDIF in the setup of the program you use for playback, tells the program not to decode the signal. So a DD sound file will get sent to the Rotel as a DD signal and not as PCM.

I had the exact same problem 2 years ago on my RSP1069 trying to playback a movie with DTS sound, and I could only get 2 channel PCM no matter what I tried because I kept thinking I had to use the control panel for sound.

Back then I used ffdshow, I finally figured out I had to use these settings to get it to work and select 'pass-trough'.

[RoMan]

Hi all,

I figured it out. The mac does support Dolby Digital 5.1 via its DVD player application. You must go into DVD Player- Preferences- Choose Disc Setup- Choose- HDMI or Digital out- make sure in your preference pane that its also enable in there. Output should be either HDMI(it will recognize component, in my case it says ROTEL AVR) or Digital out port. Only DD 5.1 dvds are supported, no DTS, Pro logic IIx, is supported. When playing cd's it is only 2 channel stereo because of the source. Thanks hurin and mjb. I know what you mean now hurin. I would need to buy software or maybe a logitech device to decode PCM and give me Pro Logic IIx. That will be down the road though at this point. Thanks for your input and it is time to start rocking again.. :B

RoMan :T

[hurin]

Good you figured it out.

DD is part of the DVD standard whereas DTS is optional, so all DVDs have DD but only some have DTS. I can recommend using VLC instead, it's free and will handle just about anything.

I'm not sure I understand why you can't get Pro logic IIx. If the Rotel is fed a stereo source, all you need to do is press the DD button and you'll get Pro logic IIx.

[RoMan]

Thanks Hurin, you're right. I just hit the DD button and presto on came DD PLIIx M. So all is well in the audio world and everything is working as it should. Thanks for your help. I will take a look at the VLC site and check it out. Cheers and all the best. Thanks again.
:T RoMan