Firewire Question for iMac

I am about to purchase a Weiss Dac 2. The manual says to use a 6 pin to 6 pin 400 Firewire connection. Just making sure here - is the iMac Firewire 400 port a 6 pin port and do I purchase a 6 pin male to male cable for this connection?
The recent generation iMac's do not have a Firewire 400 port. They have a Firewire 800 port instead, which uses a 9-pin connector. You would need a 9-pin to 6-pin cable, also known as a "bilingual" cable. Granite Digital makes some good ones, although they are a bit more expensive than run-of-the-mill cables.

Firewire 800 is backwards compatible with Firewire 400 devices except for the cable type.

-- Al
Thank you for the response Al - my iMac has both Firewire 400 and Firewire 800 so I guess it is already an older version! LOL! Given that I have the 400 port then 6-pin male to 6-pin male is the right choice. BTW, I use the 800 port for an external HD.
iMacs produced between 1998-2009 had Firewire 400 (6 pin). iMacs produced after October 2009 had Firewire 800 (9 pin). All new iMacs have Firewire 800 (9 pin). There's a good reference article here:

The Weiss Dac 2 has Firewire 400, so if your iMac is older than Oct 2009, you'll need a FW 400 cable like this:

If your iMac is newer than Oct 2009, you'll need a FW400 to FW800 cable like this:

Or you can use a FW400 cable with a FW800 adaptor on one end:
Mingles thanks so much for your response. It was very helpful. Since my FW800 port is being used for an external HD I will use the FW400 for the Weiss. It will be a straight 6 pin to 6 pin.

Not sure why my iMac has both FW400 and FW800 but heck, I'll take it!