Why Mountain Grass Unit Ditched the Click Track: Bluegrass Soloing, Mash Rhythm, and Playing Organic

From a Volkswagen to the Grand Ole Opry

Few young bands have climbed as quickly as Mountain Grass Unit. Guitarist Luke Black, mandolinist Drury Anderson, and bassist Sam Wilson grew up together in Birmingham, Alabama, and started gigging as a trio around 2018. Fiddler Josiah Nelson joined after Luke met him at a jam while touring East Tennessee State University. Their first real tour was a week and a half crammed into a tiny Volkswagen. Today they travel in a Mercedes Sprinter with a trailer and a full crew.

Sitting down with host Spencer Handley at Carter Vintage Guitars in Nashville, the band credited two things for the momentum: a booking agent who got them into new markets and festivals, and a steady stream of social media content, from live clips to goofy skits.

The last year has produced some remarkable stories. They opened the Bonnaroo Super Jam as Kesha's backing band, playing a bluegrass take on Britney Spears' Baby One More Time. At DelFest, Del and Ronnie McCoury walked back onstage after their set and Del asked into the microphone whether the boys would like to play the Grand Ole Opry. Then he overruled the stage manager and sent them back out for an encore.

Fun stories aside, the real value of this conversation for guitarists is how openly the band explained the way they build solos, support each other, and think about theory.

Breaking Down Luke Black's Viral Telluride Solo

A clip of Luke soloing at Telluride crossed a million views and earned a nod from Billy Strings. Luke admitted he could not replay it note for note, since it was improvised. What he could explain was the method behind it.

That solo is just kind of a bunch of ideas phrased together to kind of create something that's more memorable rather than just a stream of consciousness.

That is the key insight. A fast bluegrass solo is not one endless run. It is a series of short ideas, each stated, repeated, and then developed or swapped for a new one.

Idea 1: The Tony Rice Rake and Bend

The solo opens with a rake into a bend, a move straight out of Tony Rice's playbook with a bluesy edge. It lives in minor pentatonic, but Luke adds the major third and the flat five. That blend of major and minor color is the heart of bluesy bluegrass. Then, as he put it, it's bluegrass, so you have to end on a G run. Luke plays this phrase, repeats it, and only then moves on.

Idea 2: The Pull-Off Cheat Code

Luke called this one the ultimate cheat code for sounding faster than you really are. The right hand plays steady down-up alternate picking while the left hand adds a pull-off inside the pattern. The result is a cascade of notes that sounds blistering but asks much less of your picking hand. Because it is a shape, you can move it anywhere on the neck. Starting it on the flat third and passing through the flat five keeps it bluesy, and Luke likes to resolve it onto a strong chord tone to release the tension.

Idea 3: Mixolydian Lines Through an F Shape

The song was in A with a capo, so Luke was thinking in G shapes. He described a lot of bluegrass as built from the Mixolydian scale, and here he outlines an F chord (the flat seven in G) using notes from G Mixolydian before resolving up. Spencer called it a backdoor dominant sound, and Luke agreed. That bVII to I motion is common in rock and blues and adds a warm, slightly unexpected color to a bluegrass break.

Idea 4: Vamping on One Note

Here Luke credits Billy Strings. He repeats a single note in a steady sixteenth-note rhythm, which he joked gives him a chance to regain control if he gets lost. Musically, it builds momentum and gives the listener a breather from melodic information. From there he jumps into a minor pentatonic pattern, again with the flat five, played in a spider-exercise style that climbs to a top note to close out the break.

Bonus Lick: Minor 7 Off the Five

Luke shared another favorite: in the key of A, play an E minor 7 arpeggio shape (built on the fifth) over the A chord. The notes E, G, B, and D give you the fifth, flat seven, ninth, and eleventh of A, a smooth, extended sound without leaving the familiar minor 7 shape you already know. Spencer pointed out you could also hear it as a C# half diminished sound. Either way, it is one shape with fresh results depending on where you land.

How to Avoid Run-On Sentence Solos

Spencer raised a common problem: solos that sound like one long run-on sentence. The band offered several approaches.

• Think in checkpoints. Luke does not count bars while playing. He hears the story of the solo moving through cycles of four, eight, or sixteen bars, and he aims his ideas at the downbeat where each cycle resets.
• Channel another player. Josiah asks himself who he would love to hear on a tune, such as Michael Cleveland or Kenny Baker for traditional material, then imagines what they would play. This limits his choices in a useful way.
• Sing your lines. Both Josiah and Luke stressed singing or humming phrases. You cannot sing an endless string of sixteenth notes, so singing naturally forces you to breathe and phrase.

Mixing Scale Colors

Drury added the mandolin perspective. Over a dominant vamp, he moves between Mixolydian and a minor blues sound, which he described as Dorian without the second or sixth (essentially minor pentatonic). Good blues players, he noted, never sit on one scale over a long one chord. They drift between major and minor colors, building tension and releasing it. He also leans on double stops and Sam Bush style hammer-on licks, which are great tools for any guitarist who wants variety without more speed.

The Rhythm Section Is Part of the Solo

One of the most useful parts of the discussion was how the band supports a soloist. Drury explained that when Luke plays Mixolydian ideas, he might comp a straight G. When Luke shifts to minor pentatonic licks, Drury might play a C (sharing the flat third) to reinforce that darker color. He also walks up chord inversions in half steps to build energy as a solo winds down.

Sam described the bass role in a drumless genre: rhythm plus emphasis. If the mandolin is busy, he plays less. If Luke goes low for a bend, Sam dances around it so the idea stands out without stepping on it. Everyone, Drury added, must track the band's intensity. You lead when you solo, but if the band is not following, you adjust and reset at the next cycle.

What Is Mash Bluegrass

Sam mentioned the band loves mash, a style of bluegrass that grew in the 1980s and 1990s. It is extremely aggressive and downbeat-centric, driven largely by the banjo, and played far on the front edge of the beat. Traditional bluegrass, by comparison, sits a little more laid back, and the band pointed to Tony Rice style rhythm as a more flowing example. All bluegrass leans forward, but mash takes it to the extreme. There is also a mash culture, with festivals built around it.

Theory as a Language, Not a Rulebook

Three of the members studied music formally, with Luke at Berklee. They were refreshingly practical about it. Theory is worth using only when it makes something easier. Its biggest benefit is communication, since shared terms let them quickly tell each other what they want. Drury compared it to a hammer in a toolbox: you can drive a nail with a screwdriver, but some tools make the job easier.

Luke said the most valuable thing from Berklee's guitar program was early fretboard mapping. Running scales and arpeggios felt pointless at first, but it gave him landmarks across the whole neck where he knew every mode would work.

Lessons From the Fiddle

Josiah grew up in Fort Collins, Colorado, taking private lessons in a fiddle tradition with deep teaching roots. Bluegrass has always relied on one-on-one oral learning, where a teacher passes everything down and the student pushes it forward. A teacher once told him he needed a rhythm instrument, and he eventually took that seriously, studying rhythm guitar with Wyatt Rice at ETSU. Now he says sitting and playing rhythm for hours is his favorite thing in the world. That is a lesson every lead-focused guitarist should hear.

Why They Dropped the Click Track

The band's new album, recorded with producer Vance Powell at Sputnik Sound in Nashville, is their first made without a metronome. Their reasoning was simple: they play so many live shows that a click felt foreign. Bluegrass, as they experience it, is supposed to flow, and the energy naturally pushes forward. They cited the Allman Brothers as an example of bands that let the jam breathe. The result, they say, is the most authentic record they have made.

That does not mean metronome practice is useless. It means internal time and band chemistry eventually matter more than the grid. Practice with a click to build reliable time, then play with people to learn how time lives and breathes.

Practical Takeaways for Guitarists

• Build solos from short ideas. State a phrase, repeat it, then develop it or move on.
• Learn the alternate picking plus pull-off pattern to add speed without strain.
• Blend the major third and flat five into minor pentatonic for a bluesy bluegrass sound.
• Try outlining the bVII chord with Mixolydian notes for a backdoor resolution.
• Play a minor 7 arpeggio from the fifth of the key to get extended color tones.
• Sing your phrases to break the run-on sentence habit.
• Practice rhythm guitar as seriously as lead, and listen to the intensity of the band.
• Map the fretboard with scales and arpeggios so you have landmarks everywhere.
• Fix awkward fingerings when transcribing. If a lick feels painful, try another string or picking pattern.