Yeah I know about 5.1... haha the problem is money. I'm already buying a Marantz 4400 tomorrow. I have a 4240 and I tried feeding two NuForce DAC's into it one playing the rear channels into the rear inputs and the other playing the front into the front inputs, the 4240's Power-mode switch is in the 4 channel position (for future people if you read this NEVER change the power mode switch on the back of a Marantz Quad unit while it is powered ON) and nothing comes out of the rear... I am not sure if because it is two sources and that the Marantz is supposed to decode from a proper source and does not know what to do with it so it just plays the front or what is going on.
If you connect your DAC outputs to the CD-4/Aux front and rear inputs, then set the selector to CD-4/Aux, and the MODE switch do DISCRETE, you should get all 4 channels. Make sure you have audio coming out of all 4 DAC outputs. You can swap the front/rear DACs to make sure.
The SQ decoder was optional, which is strange because there was far more SQ material available than discrete quad. Apparently, Marantz felt their own "Vari-Matrix" decoder was good enough, and it probably was. If you wanted to have all your Quad format bases covered, you'd have had to have at least 3 different decoders! That's one of the other reasons Quad failed, market confusion. The SQ decoder (or varimatrix) is not used for discrete 4 channel sources. The CD-4 decoder would have been an external box.
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