Practice playing through chord changes, voicing double stops, incorporating rhythms/bowings, transposition, and micro improvisation along with real songs in order to move them from theoretical knowledge to intuitive playing.
These skills make up not only my own practice routine but the central curriculum of my Bluegrass Country and Roots School
(See the Curriculum here: Roadmap to Bluegrass / Country Fiddle Mastery)
I use this playlist to practice every day:
I use "Banks of the Ohio" because I just love a good murder ballad... Haha no, just kidding.
It's the perfect song for this kind of work because it's a slow tempo tune and the chords change more slowly than most songs- giving you plenty of time to work on whatever you have chosen to focus on.
Try incorporating one or two Ideas from the Roadmap to Bluegrass / Country Fiddle Mastery and sustain that focus throughout the practice session.
Other Backing Tracks I Recommend:
Free Bluegrass Backing Tracks - This free website has a mix of bluegrass fiddle tunes, irish, Old Time, and gypsy jazz tracks. It also has a section on common chord progressions.
Bluegrass Backing Tracks (YouTube) - This one is great for fiddle tunes and Traditional Bluegrass Songs. They are professionally recorded and many of the songs include lyrics.
The Binary Woodshed has the best Country Western/Swing tracks (Seriously, these are REALLY fun)
Rhythm Future Quartet has the best gypsy jazz backing tracks. They are recorded by a killer string band quartet by the same name. Check out their music.
Train Beat (YouTube) - I use this to get the feel of country/bluegrass music without a specific key. Great for exploring bowings, feel, and common accents.
Strum Machine - Huge library of songs and tunes with great visual aids that follow the form of the song. (You can even create your own backing tracks here)
“Country/Bluegrass Karaoke" playlist - Here’s my personal playlist that I often use for solo gigs. Hook this bad boy up to a good bluetooth speaker and you’re good to go!
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Backing tracks are excellent for generating motivation and they elevate your practice by holding your timing and pitch to a professional standard.