String Rating: Knobloch Erithacus EDB31.5 Low Tension

I tried the new strings released by Knobloch. This series, called “Erithacus”, aims for a “natural sound” and has a lineup of treble strings using a new material called bio-nylon. I bought and used these strings and found them to be unique and fun to play for the first time in a long time.



Erithacus, meaning the genus of robins.

The name of the series, “Erithacus“, refers to the bird genus European robin. I’m not sure which bird it is, but from the picture it looks like a European robin (Erithacus rubecula).




This string was recently released by Knobloch along with the Asad Brothers Memorial model. I have already purchased the Asad Brothers model and will be reviewing it.


A model using bio-nylon exists

This series is characterized by the use of what is called ER Double Silver for the bass strings.

It aims for a natural, round sound and is available with the following treble strings:


Notable among these are the bio-nylon model that use plant-derived materials.


The use of bio-nylon eliminates the “plasticky” sound found in nylon and carbon strings, and is said to provide a pure, natural, round sound.


I think this EDB model is the main one of the Elisacus series because the concept of bass string is also natural sound.


When it comes to bio-nylon, Aquila’s Perla uses the same material.


There are only a limited number of sources for treble strings, so maybe the treble strings for the EDB models are supplied by Aquila.


New product strings arriving in an incompleted state

I ordered the Erithacus bio-nylon model directly from Knobloch about right after it was released, but they hadn’t made the package yet, so it came in this package:




What a surprise, it had my name on it. By the way, the packaging was very careful and I was very satisfied with the product, except that it took a long time to arrive.


Thus, there is no information on the back of the package, and here is an image what I borrowed from the Knobloch website.



The emphasis is on the “natural sound” of both the bass and treble strings.


By the way, the model name is “EDB31.5”, and the “31.5” seems to indicate that the total tension is 31.5 kg (is the 31.4 in the image above a misprint or a value under development?).


It sounds definitely low tension string.


Red markings on 2nd and 5th strings

The strings came in one airtight package with all six strings as shown below.



In the case of the Double Silver series, the bass strings and treble strings were separated, so maybe they will be separated when the package is completed.

Although there are six strings in one package, the ends of the second and fifth strings are marked in red, so there was no problem distinguishing the strings.




The bass string is looped at the ends, including the metal wire.



I think it is common not to attach this loop part to the bridge, but if you leave it as it is, it won’t go through the peg, so you need to cut it.


Knobloch may ask us to use this side for the bridge side so that you can easily stop the strings. I would like to ask the manufacturer.


Milky white, thick treble strings

The distinctive feature in terms of appearance are the treble strings, which are milky white rather than transparent.


This is a characteristic of strings made of bio-nylon, and Aquila’s Perla was no different.

However, if you use all bio-nylon strings, you will not feel strange as following image.