Sunn Sceptre Output Impedence

[Sceptre]

Hey dudes,

I've recently become a proud owner of a Sunn Sceptre, and I am a giddy little bitch about it. I'm looking for a matching 4x12 cab (or possibly a 6x12...) but in the meantime I'm using a Marshall 4x12. I'm confused about the output of the Sceptre. I realize this is a super newbie question, so apologies in advance.

On the back of the head, there are two jacks: "8 ohm speaker" and "4 ohm extension speaker."

Does this mean that the first jack used alone is 8 ohm out and the second used alone is 4 ohm, or is it suggesting that they're both 8 ohm outputs, but used together they produce a 4 ohm load?

As most Marshall cabs, mine has a mono 4 ohm or mono 16 ohm input, or two stereo 8 ohm inputs. If the second jack is 4 ohms, I can just run it into the mono input. If they're both 8ohms mono and used together a 4 ohm load, how could I hook it up to the Marshall correctly and use all 4 speakers?

Please help! Again please excuse my ignorance here.

Thanks!

[EdBass]

If you use either jack by themselves they are as marked, when you use both jacks they default in parallel to the 4 ohm tap.
So, you can use two 8 ohm speaker loads at the same time, or one 4 ohm speaker load to the 4 ohm jack, or one 8 ohm load to the 8 ohm jack.

Use the search function; the Sunn output jacks have been discussed many times in many threads.