Interview with string expert Sandra Kirschbaum: about the traditional company Kirschbaum and the world of strings

In our string world today we will find out a lot about tennis strings and their importance for every player interview with Sandra Kirschbaum It is exciting to find out how the family business has developed over the last 35 years. But not only the company, but also the world of strings itself has changed immensely in recent years.

Let Sandra take you on a journey through time and find out how you can find YOUR perfect tennis string

Sandra, you are THE expert for strings and coverings. How did your love for tennis strings come about?

I take the title THE expert as a compliment. In fact, there are many, many experts in this field among stringers and racket tuners. But perhaps I am the busiest when it comes to individual advice and support on the material PROVIDERS side. This is probably due to the passion with which we have worked in our family business for 35 years - I would be nothing without my team. Since we have always specialized in tennis strings, we have had thousands of conversations with players, stringers, shop owners, coaches, parents and tournament organizers over the years. I have never played at a professional level myself, but over the years I have spoken to hundreds of professionals, listened to them and tried to understand how they think and what they expect from the material.  

Tell us something about your company. Where are you based, how many employees do you have, where does production take place? In which countries do you operate? Do you only sell the strings directly or what sales channels do you have?

We have been based in Witten since 1987. My father founded the company with his wife, with whom he had previously run a successful real estate sales and hairdressing shop 😉 My father was a creative, self-made guy with a doer woman at his side. I have been there since 1991 and together we built up sales outside of Germany. Cherry tree strings are available from Australia, Asia, Europe to North and South America. We have been working with some partners for over 25 years. We also have consistency among our employees, some of whom have been there for over 20 years. Horst unfortunately died in 2010, but my mother is still there. We have a total of 14 permanent and part-time employees. Our core products are made in Germany, we hold patents for surface treatment and global sales are handled from our headquarters in Witten.

Your company Kirschbaum has been on the market for 35 years. Take us on a short journey through time with strings. What technological developments have there been? How has the market and your company developed?

Between 1985 and 1987, my father and a partner worked on new string materials and processing techniques on converted machines from the cable industry. A first extruder was quickly purchased. After a few attempts and initial test series, my father started out in 1987 as a supplier to large racket companies - with OEM goods, so to speak. He quickly had good contacts and companies with regular orders. Soon there was a partnership with a racket manufacturer and a cherry tree racket series called "Independent" was produced - the special thing: an adjustable handle. This was presented at the ISPO in Munich on its own stand at the old exhibition center. At the same time, there were the first polyester strings in white and natural with the product names GUT FEELING, SUPER SMASH and LONG LIFE, which were sold under the company's own KIRSCHBAUM brand. Back then, the logo was a sweetspot-filling tree, which was only replaced by the cherry in the early 90s. The string qualities quickly became popular and spread among frequent players. Marketing the racket was difficult as a tennis novice without the necessary capital and was discontinued. The focus was on the strings and the Kirschbaum brand name. The interest of the German ranking players awoke. The first hybrid string under the name TOUCH DUO was born - lengthwise polyester in 1.35 mm and crosswise a polyamide string in 1.25 mm.

With the expansion of sales beyond Germany from 1991 onwards, good contacts were gained with professional players, especially in Spain, Italy and South America. Western grip and topspin led to more string wear and increasing demand for polyester strings. The breakthrough came after 1996 with the new edition of the SUPER SMASH - HONEY - the first polyester string in a beautiful color, reduced color pigment content and, above all, for the first time in 7 individual diameters - 1.225, 1.275 and 1.325 mm were born. The player response was gigantic. Many young and adult players in Germany and internationally were quickly signed up as brand ambassadors with the cherry. This was followed in 1997 with the SUPER SMASH SPIKY, a string with patented surface profiling. At the end of the 90s/early 00s, every second ranked player played with the “cherry” as a logo (including Mischa Zverev, Florian Mayer, Angelique Kerber, Anna-Lena Grönefeld and many more) among the top 800 of the ATP/WTA over 300 players (including Carlos Moya, Dominik Hrbaty, Karol Kucera, Guillermo Canas, Gaston Gaudio, Patty Schnyder, Anastasia Myskina, Caroline Wozniacki, Vera Zvonareva).

The company grew, exported to 50 countries, and mail order companies and sports stores served tennis-loving players in Germany. The tennis string also came into focus as an important element among racket companies and due to the growing competition among the top racket brands, which only tolerated their own logo for their contracted players, the second logo of the string sponsors increasingly disappeared - and so did the cherry. To be honest, one has to say that the competitive pressure among the pure string specialists also increased and there was significantly more crowding out on the market - at the same time Kirschbaum, as a family-run company, was somewhat "weakened" by the illness of the company founder and the birth of our two children.

Other important products in the early years were the multifilament string PX12, the TOUCH TITANIUM (test winner in Tennis Magazine 99), and later the GUT FEELING (test winner in TENNIS MAGAZINE 2017).

The new sales channels through the Internet, online retailers, global trade, and Corona have presented us with new challenges. But our direct contact with the customer, stringer, player, our qualities and our good service ensure consistently good sales figures and the positive feedback encourages us on our path. Now we have to ensure that we also make the brand known to young players and continue to supply all other player age groups with consistency and product diversity.

What potential actually lies in the individually “optimal” string?

So, what is the optimal string? It doesn't have to be the most expensive, it doesn't have to be the newest. What we are looking for is the string that fits the player and racket optimally, the string with which the player feels comfortable and with which he can play his best tennis. Honestly, even our strings can't do magic. But if the string does NOT fit, it blocks the player and, in the worst case, puts strain on the player. There is a lot of need for clarification here and personal advice is actually required - you can't say that across the board. That's why we offer every player a consultation form on our website ( www.kirschbaum-strings.de/beratung ). The string can certainly influence the length and speed of the balls as well as the trajectory. The issue of durability should play a minor role.

Why do you think the subject of “strings” is treated so neglectfully by so many tennis players?

Professional/tournament players know how important the string, the diameter and the string weight are and what influences are associated with them. In the recreational sector, many players don't come into contact with it at all because they have never been advised in this direction. Coaches often don't have the time to discuss these topics in training, so players grow up without an awareness of the importance of the string. Stringers / sports shops also rarely have the opportunity for a real consultation with the customer and unfortunately, when it comes to money, customers often don't have an ear for tips, which may also lead to higher stringing costs. It's tricky. And then comes the abundance of products, so that the interested user is flooded with offers and products, forums and recommendations. You quickly lose sight of the goal.

How do I find the right string for me? How can I proceed? What do I have to consider?

As I said, everyone can get advice from us. But independently, there are perhaps a few tips: choose strings as thin as possible so that you are just as satisfied with the durability. A thinner string supports spin better. Choose the weight as low as possible so that the racket still has good overall length control. Less weight results in more relief in the arm and also increases durability. Do not play polyester strings for too long - the material is not designed for that. The strings also lose their quality over time. You adapt unnoticed and you don't consolidate your technique. As a rule of thumb, we recommend changing your strings at least as often during the season as you play in a week. For players without wear and tear, I would recommend trying a polyamide string instead of poly - don't let it stop you from slipping. This is not a quality defect.

Since when have you been playing tennis yourself? Do you still play you? If so, how often?

I started as a child and also had training. In my youth - when tennis was really booming 😉 - I played in the women's team, it was very stubborn and ambitious. Unfortunately, that took away my fun and puberty did the rest. It wasn't until later that I started playing with my own children again. So I've never been a professional, nor do I play well myself.