D'Addario K420L-5 E Violin Strings

Kaplan Golden Spiral Solo E String for 4/4 Violin — Heavy Tension, Loop End

The D'Addario Kaplan Golden Spiral Solo Loop End Violin Single E String, 4/4 Scale, Heavy Tension is a single replacement E designed for full-size violins. Built around a precision high-carbon steel core with a gold-plated finish, this string delivers the traditional rich, vibrant tone expected from a high-quality steel E. The "Golden Spiral" name refers to the plating process, not a colour, and the result is a string that combines the brilliance of steel with a warmer, more rounded top end than plain unplated E strings.

At heavy tension, this E is the choice for players who want more volume and projection than a standard medium E provides, particularly in solo repertoire, unaccompanied Baroque works, and recital settings where the E line needs to carry over the lower strings. The string is scaled to a 13-inch (328 mm) playing length to match standard 4/4 violin geometry, and the loop-end fitting suits violins equipped with loop-style fine tuners and tailpieces.

All Kaplan Golden Spiral Solo E strings are designed, engineered and manufactured in the USA under D'Addario's computer-controlled winding and quality-control processes. A short break-in time and excellent bow response are part of the design brief, so the string settles into its playing character quickly and tracks cleanly under the bow across dynamic levels.

Technical Specifications

• Brand / Series: D'Addario Kaplan Golden Spiral Solo
• Model Code: K420L-5
• String Type: Single E (replacement string, sold individually)
• Material: High-carbon steel with gold plating
• Construction: Unwound plain steel E string
• Tension: Heavy
• Scale / Size: 4/4 (full size), 328 mm (13 in) playing length
• End Type: Loop End
• Country of Manufacture: USA

Who It's For — Soloists, Advanced Students, and Recital Players

The Kaplan Golden Spiral Solo heavy-tension E is aimed at professional and intermediate violinists who want a steel E with extra body and projection. It suits solo performance, chamber music where the E line needs to lead, and advanced students moving up from a lighter tension who want a more powerful top string without changing to a wound E. The loop-end fitting makes it a direct swap for violins already set up with loop-end fine tuners, and the gold-plated steel construction gives the characteristic bright, focused E sound with a touch more warmth than a plain steel E.

Within the broader Kaplan Golden Spiral Solo E range, four tensions are available (light, medium, heavy and extra heavy), so a player can step up or down in tension to match their instrument's response. The heavy variant sits in the middle of that range and is the most common choice for players who feel a medium E lacks projection on their particular violin. As with all Kaplan E strings, the gold plating is applied through a precision process designed to deliver a consistent, traditional steel-E sound with a short break-in and reliable bow response.