Nick Lachey of 98 Degrees knows his fan base is mostly teenage girls, but he's OK with that. Those fans pushed sales of the boy band's "98 Degrees and Rising" and "Revelation" albums to multiplatinum.

But the 30-year-old singer hopes his new solo album, "SoulO" (Universal Records) — a mixture of trendy grooves and syrupy ballads — will knock him up an age bracket or two.

Producers included The Matrix crew (who work with Avril Lavigne), Guy Chambers (Robbie Williams), and Trina Harmon and Stuart Brawley (Brandy, Michael Jackson).

Lachey and his pop singer-wife, Jessica Simpson, also star on MTV's "Newlyweds: Nick & Jessica," which follows the couple as they muddle through married life. New episodes will begin in 2004.

"Newlyweds" has made the 23-year-old Simpson (who's reached a deal with ABC to develop a comedy) infamous for her dippy-blonde moments, including the time she confused the tuna she was eating for chicken.

Meanwhile, Lachey says he may try acting while 98 Degrees is taking a break from recording and touring.

AP: Do you think the boy band days are over?

Lachey: I think that we see music as cyclical. I shudder to think it was called the `day of the boy band,' we never intended to be swept up by that whole movement. I think there will be an opportunity for harmony groups to be successful again. I'd like to do another record with the group at some point.

AP: How much control did you have over "SoulO"?

Lachey: It's a compromise; maybe some songs I didn't want to do are on the album and some songs the producers didn't want are. We'll see how this thing rolls, music is something I love to do and will always love to do. But I'd like to create a different atmosphere where I can have more control over the album, work with one producer, one writer.

AP: Will your fans like it?

Lachey: I would hope that fans like the record, and they will like the songs and me as a singer. I guess there might be a small percentage of people that it could be a problem for, but I did the album for the fans that were still loyal to 98 Degrees, and as I evolve as a singer and hopefully tap into new fans.

AP: Do you think your wife is a ditz, especially after the "chicken by the sea" guffaw?

Lachey: I think she'd be the first to admit that she has ditsy moments, and it became evident very early on that it was going to be a major plotline on the show. But come on. She's not Anna Nicole Smith or anything.

AP: Who takes longer to get ready to go out, you or Jessica?

Lachey: She would say me, but it's definitely her. I'm at the bottom of the stairs yelling that we have to go and she's nowhere near done.

AP: Are you worried about becoming Mr. Jessica Simpson?

Lachey: She knows I'm her biggest fan, I cheer for her louder than anybody. I tell her all the time I'd gladly retire and hang out with the kids and clean the house. I want to have a good life and great family, and from a professional standpoint I want to be successful, but it's not the most important thing at all.

AP: How do you feel about taping more episodes of "Newlyweds"?

Lachey: It's a great opportunity for us. We're planning on being married for a long, long time. We're not going to do a reality TV show forever, but while it continues to work, we're going to continue to do it.

AP: Isn't married life hard without being filmed all the time?

Lachey: The thing is, we don't really know any different. We got married in October of last year, and we started taping in the spring. We don't have any concept of marriage without the cameras yet. I think you have to not take the show too seriously; not get caught up with things that are edited on the show. You get the gist of what's going on with us, but they tape for four months and you see ten 22-minute episodes. It's not a documentary of our marriage. There's plenty of stuff, good stuff and bad stuff, that didn't make the show for whatever reason.

AP: Any advice for young married couples?

Lachey: I always feel stupid giving advice since I've been married, what, a year? I can say this: Be in it for the long haul and just know there are going to be rough patches. No two people are the same, there are going to be areas where you just don't click.