Virtuoso Milwaukee jazz guitarist and author has just released his 20th CD.

The multi-talented Grassel played nearly every note on "2015 Jack" – which features a mix of original material and standards – but what’s most surprising is his collaboration with Mexican rapper Tacuako, recorded in February in Cancun.

We caught up with Grassel to ask about the record, the collaboration and more.

OnMilwaukee.com: This is your 20th CD. That must make you feel proud.

Jack Grassel: Yes, I'm proud, every time I make a recording, I feel there must be a musical reason to do so. I am always changing and growing and I'm grateful for all my fans that remain interested in my work. Now, the age range of people at my gigs can be all ages from early teens to seniors. I like the Keith Jarrett quote: "The truly valuable artist realizes the impossibility of his task and then continues to do it."

OMC: With all those years of music behind you, how do you keep making music that is interesting and engaging not only for fans but also for yourself?

JG: I started music lessons at age 3 and began playing professionally – for money – at the age of 4. I'm continually fascinated by the process of making music, playing instruments and interacting with audiences. I love it. There's always new music to play and new instrumental techniques to work on. I have practiced every day for the last 63 years. I have to constantly change and develop what I'm doing to remain excited and interested in the music. No one hears me play more than I do and it's not always good but I am starting to get better at it.

OMC: You recorded with a Mexican rapper. Tell us about how that came about.

JG: Tacuako tends bar at one of the venues we play at every winter in Mexico. He's also a popular rap star in Mexico. He started to sit in every gig and improvise a rap on whatever song we happened to be playing. Those interactions became very popular with the audiences. One day he asked us to compose a song to go on his new compilation CD. In the studio, (Grassel’s wife and singer) Jill (Jensen) and I composed the song, recorded it and then Tacuako wrote a Spanish rap text to record over the tracks we had just recorded. We are a guest on his new CD which has been released in Mexico and he is a guest on my new CD released in the States. It will be interesting to see what happens this year when we go back to Mexico. He granted us permission to use this track on my new CD.

OMC: Surely, it's your first time recording with a hip-hop performer. Are you always seeking out collaborations like these or do they just have to happen organically?

JG: Good question. I don't have biases regarding musical genres. Either music is "musical," original, is performed well, has feeling and makes a statement or it doesn't. Tacuako is a great musician and rapping is his instrument. There is good and bad rap in the world just like there is good and bad anything. At our gigs, if I was playing a jazz standard like "Stella By Starlight" or "Giant Steps," Tacuako would rap solos on the jazz forms in the same manner as a master jazz musician does. He knows the forms and would rap correctly on them whether it was a 12-bar blues or a 32-bar AABA Jerome Kern song, spontaneously improvising a text that rhymed. It is amazing to hear him do that.

OMC: You played absolutely everything on the record except ride cymbal on one track, right? Was the ride cymbal just outside your skill set or did you bring in Mark Pulice because you did not want to come across as too insular?

JG: (Laughs) I went to Schmitt Music to look at ride cymbals to find the perfect sound for me to play on that track. Mark Pulice is the drum technician there. He was helping me find the right cymbal and the right sticks to produce the sound I wanted. He was demonstrating all the equipment which was awesome to listen to and I've always been a fan of his playing. It was his lunch break, so I said "grab your favorite cymbal and sticks and I'll take you to the studio to play on one track." I had him back at the store within an hour and was very happy with what he did.

OMC: What's the tune or performance on the record that you're most proud of?

JG: Since I recorded the CD in my own studio, and had no deadline for completion, I was free to take my time with everything and get it exactly the way I wanted it. I like each of the eight tracks for different reasons, the instrument choices and arrangements. I guess I'm most proud of the fact that I play 11 instruments and sing lead and sometimes four voice background harmonies. The voice parts are interwoven with the instrumental parts, avoiding the standard – and boring – old jazz format of: first someone sings than a bunch of guys play solos and then someone sings the same thing again. I avoided repetitive formats.

OMC: Any thoughts yet for No. 21?

JG: Yes, I will keep recording but whatever I do it will be different than what I've already done otherwise there is no reason to record again.

You can catch Jack Grassel Monday, Aug. 10 at the Italian Community Center in the Third Ward from 6:30 until 9 p.m., and Sept. 20 at Milaeger's Great Lakes Market in The Exposition Building in Racine, from 10 a.m. until 2 p.m.

Grassel’s new CD is available directly from Jack at his performances, at Schmitt Music in Racine, Lincoln Music in Milwaukee and via his website, jackgrassel.com.