Audioquest Makenzie XLRs

Are you buying interconnects for 2 channels or 7 channels (or somewhere in between)?

Why XLR? I don’t believe either the Marantz or ATI are differential balanced. 

I’m a big fan of AudioQuest,  However, I’m not sure I’d throw a lot of money at cables for your system. I once did that for a 5-channel dual purpose AV system. Even with a good deal on cables, the $$$ add up quickly. 

In short, XLR isn't necessarily better. However, the ATI 2007 is a balanced amp, and the Marantz 7704 will output a balanced signal, so in this instance, I'd be inclined to try a balanced cable.

Not to complicate matters, but you'll want to verify the pin arrangement on the ATI 2007. According to page 43 of the Marantz 7704 manual...

A GND (Ground)

B HOT (+)

C COLD (–)

The PIN arrangement in this device uses the European method. In the USA method, B is COLD, and C is HOT.

When connecting a device that utilizes the USA type of PIN arrangement, replace the B and C plugs on one side of the balanced cable.

If the ATI 2007 is arranged with B as COLD, and C as HOT, you can always just refers (+) and (-) speaker connections to preserve polarity.

Just flip the speaker cables on the amp side (+) -> (-), and (-) -> (+) and leave the speaker cables on the speaker side (+) -> (+), and (-) -> (-). You can "fix" it through XLR cable modification, but then you'd be messing with perfectly good cables, and can solve the issue in a much simpler manner.

If we weren't having this conversation, you'd probably never know the difference if you didn't flip the polarity, but since you're on AudioGon, you're probably OCD like the rest of us. 

Whoa...

We're mixing things up and (potentially) going to confuse the OP.

Quite simply, pins 2 and 3 are reversed on the pre-amp (w/ respect to what is normal in the US). In all reality, this should make absolutely no difference in what is "seen" by the amp, as the signal on pin 2 and 3 are, regardless of the "European method" or "USA type of PIN arrangement", a simple signal inversion IN THIS SITUATION. The suggestion to reverse the speaker cables is simply a hyper OCD suggestion (and is technically, not necessary). 

OP, you'd probably be better off if you ignored this thread, plugged-in some balanced XLR cables, and enjoyed the music.

If I were in your shoes, I’d go with the Mogami Gold Studio Microphone Cable and not look back.

You made a wise choice.