Glen Campbell made a rare appearance in Nashville last week to perform for an invited audience in an intimate setting -- the downtown studios of Sirius XM satellite radio. The 75-year-old, backed by a band that includes three of his children, introduced tracks from his critically-acclaimed 'Ghost on the Canvas,' released August 30, and also treated attendees to his chart-topping crossover smash, 'Rhinestone Cowboy.'

Playing guitar flawlessly and singing with the same impeccable skill and passion for which he first gained a worldwide following in the early 1960s, there was in his performance scant evidence that Glen is, as he recently disclosed, battling the early stages of Alzheimer's disease, save for a tendency to sometimes repeat himself or to stumble over a lyric or two. But while he told the audience more than once that he was happy to be there and pleasantly surprised to find an audience waiting for him, that could just as easily be an expression of the gratitude that he's taking with him as he embarks on what he's calling the Glen Campbell Goodbye Tour, having now recorded what he says will be his last-ever studio album.

Before Glen took the stage, attendees filed into the small theater, many taking special note of a familiar, if somewhat surprising, attendee. Tanya Tucker, with whom Glen shared a tumultuous relationship in the early 1980s, was seated in the center of the room. It was her first time seeing him in 21 years.

In an exclusive interview after the performance, Tanya said the occasion, which many might have seen as bittersweet was anything but.

"There's nothing bitter about it," Tanya told The Boot. "It's all sweet. He was funny as usual and always on pitch. He's a great singer and he's funny."

While she didn't speak to him during the event, and has not spoken to him since his Alzheimer's diagnosis, Tanya said, "This thing is just a little setback." She also explained why it was important for her to be there to watch him perform.

"He's just so great," she noted. "We want him to be a long time going. Because he's such a wonderful ... legend, really. He's always been so great. He's still got it. I've loved him since I was about 8 years old. I still do. That never will go away."

Honored and obviously touched by Tanya's presence at the event, one thing for Glen that will never go away is his ability to connect with a song from another writer's pen and make it his own -- his versions of Jimmy Webb tunes such as 'Galveston' and 'Wichita Lineman' being prime (and far from the only) examples.

"The songs actually speak for themselves," Glen tells The Boot of the tracks he chose for 'Ghost on the Canvas.' "All I thought about was 'sing it in tune with feeling.' I don't want it loud, I don't want it soft, I just want it nice and comfortable because if you get the feeling out of a song, you've won the war. I've had that happen on occasions where it all just fell in place. Amazing. Everything sounds so good. It's just like you're in a room with somebody."

Filled with poetic, cut-to-the-heart lines, the songs on 'Ghost' cover a wide range, but from the opening track, 'A Better Place,' and its first line ("I've tried and I have failed, Lord, I've won and I have lost") the album serves to reflect on a life and career that, while they may not have always been perfect, have been leading to something that promises to be.

'Ghost on the Canvas' is another of the collection's more ethereal offerings but Glen's assessment of its deep, meaningful message, which he says "just knocked me down" brings it right back down to earth.

"It had me grinnin' like a dog passin' peach seeds," he says with a laugh.

While five of the tracks were co-written by Glen, other writers who contributed to the album include Paul Westerberg, Jakob Dylan and Teddy Thompson, whose easy-rocking 'In My Arms' provides the disc with one of its most exuberant turns.

"That is one of the best-written songs," says Glen of the tune. "I love songwriters. They're pouring their heart out on something where they're trying to get across the point. I've heard somebody singing [songs they wrote] where about halfway through it it'll fall down -- they go into another sphere. This end of it is so good and then they end up doing something kind of lame. But I'll finish that off sometimes. I'll call them and say I want to do this and that. They'll say, 'Oh, fine.' I'll do that but I've never taken any kind of royalty off of anyone's writing."

Although he first came to prominence as a session guitarist, Glen has long been regarded for his singing ability, which has no doubt been one key to his crossover success. It's also been, he says, one of his most important missions.

"If you've got a good song you've got to sing it good, you've got to phrase it good," he reasons. "I think phrasing is lost in the wind. I get so much inspiration from the Lord. He gives me inspiration to sing and to sing it well. That's really what I try to do when I make a record, or when I'm doing a show. Give it your best shot because you never know when you're going to be able to give it another shot."

The next stop on Glen's Goodbye tour takes place October 1 in Reno. He's scheduled to visit the U.K., then will return to the States in November. The tour is currently slated to finish up on December 18 in New Mexico. Keep track of his tour dates here.

Also in the works is a feature film based on the legendary entertainer's life and career. In advance of that project, producer James Keach, who was a producer of the Oscar-winning Johnny Cash biopic, 'Walk the Line,' is producing a documentary film chronicling Glen. The singer says he's confident the end result of both films will be fair and honest portrayals and at this point in his life he has no issues with a "warts-and-all" approach to what has been a remarkable -- and remarkably complicated -- life.

Watch Glen Campbell Live in Our Studio

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