Could you have mania without obvious depression in bipolar?

High but not low?: You could have a first episode of mania and have depressive episodes later or you could already have a history of bipolar and have another manic episode with little or no depression although recurrent depressive episodes are more common. If you have mania and depression at the same time it's called mixed episode.

Yes: Some people with bipolar disorder have only manic episodes. Most have depressive episodes, too, though the depression may emerge later than the mania.