Detail 01
Phosphor bronze
Warmer and darker than 80/20 bronze, with more midrange. Resists corrosion better, so tone holds up longer.
Product detailSKU #1273887997796
DR StringsSunbeam Phosphor Bronze Medium Heavy Acoustic Guitar Strings
1/3
Independent shopping perspective
The Korena take
Phosphor bronze acoustic set in medium-heavy gauge. For flatpickers and strummers who want volume and a strong low end from a dreadnought.
Strong match
Who this is for
- Bluegrass flatpicking where the guitar has to cut
- Hard strumming on a dreadnought or jumbo
- Drop and open tunings that need extra tension
Consider the trade-offs
When to look elsewhere
- Fingerstyle players who want a light, responsive touch
- Small-body or parlor guitars not braced for high tension
- Beginners still building calluses and hand strength
What matters in use
The specifications, translated
Catalog numbers tell only part of the story. These are the details most likely to change how this product feels, sounds, or fits into a setup.
Detail 02
Medium-heavy gauge
Noticeably more tension than mediums. Louder and fuller, but stiffer under the fingers and harder on the top.
Detail 03
Sunbeam round core
Round core feels more flexible than hex at the same gauge, taking some of the stiffness out of a heavy set.
Detail 04
Acoustic set
Bronze windings need a magnetic pickup to be heard electrically — they won't drive a standard magnetic soundhole pickup well.
Final check
Know before you order
- 01Heavy gauge raises action; expect a truss rod adjustment after stringing up
- 02Vintage or lightly built guitars may not tolerate this much tension
- 03Bridge pins and end pegs are not included
Product questions
Before you decide
Straight answers to the questions shoppers most often ask about this product.
01Will medium-heavy strings damage my acoustic?
Modern dreadnoughts handle them fine. Older, lightly braced, or small-body guitars can suffer top bellying under sustained heavy tension. Check the maker's recommended gauge.
02Phosphor bronze or 80/20 bronze?
Phosphor bronze is warmer with stronger mids and lasts longer before going dull. 80/20 is brighter and more scooped when new but fades faster.
03Do these work on a 12-string?
No. This is a six-string set. A 12-string needs its own set with octave strings and lighter gauges to survive the tension.
04How much harder are these to play than lights?
Considerably. Barre chords and bends take real hand strength. If you play long sets or have hand issues, go lighter.
