A String Thomastik Peter Infeld 4/4 for Violin

The A wears out first — your hand rests on it in first position, most of your phrasing passes through it, and it is the string most often bought on its own. In Peter Infeld this A is built on a synthetic multifilament core with an aluminium winding: article PI02, 4/4 size, medium gauge, tension 5.6 kp (12.3 lb), ball end, 32.5 cm vibrating length. Of the three wound strings in the line it is the tightest — the D and G sit at 4.8 and 4.7 kp, so the middle register here is deliberately denser than the bottom. Of the set as a whole Thomastik writes that it is "a special tool that makes it easy for you to sound great", and ranks Peter Infeld "among our most durable strings" — for the string that gets used up fastest, that is an argument rather than a slogan.

🏆 SoundsGood — genuine Thomastik-Infeld strings only, made in Vienna.

Aluminium Keeps the Middle Register Transparent

A winding acts on a string like a weight: the heavier the metal, the slower the string answers and the duller the timbre. Aluminium is among the lightest metals used for winding at all, so the PI02 A speaks quickly and cleanly and the middle never turns gluey. You hear it in two everyday situations: double stops against an open D do not congeal into a hum, and a melody in first position does not need extra bow pressure to be heard in an ensemble. Silver on this string would add mass — and take away exactly that transparency.

5.6 kp — the Tightest of the Wound Strings, by Design

Across the set tension falls from E down to G, and the A takes the largest share of the synthetic voices. The practical point is resistance under the finger: the A absorbs the most vibrato and the most left-hand pressure, and slightly higher tension keeps it from going slack after a few weeks of work. It also means the A does not feel soft under the bow when you cross from the E: the difference in feel between first and second string is small, so changing strings does not force you to relearn your pressure.

Replacing One String Without Tilting the Set

This A carries exactly the tension of the A in the factory PI100 and PI101 sets — 5.6 kp. Buying it on its own while the other strings are still alive is therefore normal practice, not a compromise: bridge and soundpost stay under the same load, the 23.4 kp total is preserved, and the other voices do not drift once tuned. Since the maker counts Peter Infeld among its most durable strings, the rest of the set really does outlive the first A.

Specifications

What's Included

One A string in official Thomastik packaging marked PI02. This is a single string, not a set — the E, D and G are ordered separately or as set PI100 or PI101.

Who It's For

For the player who practises daily and kills the A before the rest of the set; for the violinist who needs a transparent, uncluttered middle register in chamber work; and for anyone building their own combination of Peter Infeld voices who wants to keep the factory A.

Frequently Asked Questions

🚚 Shipping and Payment

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✅ Quality guarantee — genuine strings only
🏪 Pickup — Kyiv, free
🚚 Nova Poshta / Ukrposhta / Meest — 1–3 days
💳 Installments — PrivatBank, Monobank

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