A data de 1656 é dada por Owen Morse-Brown (ver a postagem sobre ele). A de 1647 deve ser a correta, segundo outras duas fontes registradas aqui.
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C. (Cecie) Stainer.
A dictionary of violin makers
Feldlen, Magnus. Working in Vienna in 1556. In a viola di bordone in the Collection of the Gesellschaft der Musikfreunde, Vienna, is the label :
" Magnus Feldlen, Wien, 155').''
http://www.ebooksread.com/authors-eng/c-cecie-stainer/a-dictionary-of-violin-makers-iat/page-5-a-dictionary-of-violin-makers-iat.shtml
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Treasures from the RCM Collection
Dr Ingrid Pearson
The baryton by Magnus Feldlen of Vienna dates from 1647 and is considered to be the oldest surviving instrument of its kind. The baryton is a fretted, bowed string instrument, resembling a bass viol. In addition to the bowed strings are several sympathetic strings. The most famous composer to write for the instrument was Joseph Haydn, whose patron Prince Nikolaus of Esterházy played the baryton. The instrument flourished only from the mid 17th until the early 19th century, and even then, it was not really known outside Southern Germany and Austria.
http://www.gresham.ac.uk/lectures-and-events/celebrating-the-past-treasures-from-the-rcm-collections
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Mas:
James M. Fleming.
The fiddle fancier's guide; a manual of information regarding violins, violas, basses and bows of classical and modern times, together with biographical notices and portraits of the most famous performers of these instruments
FELDEN, MAGNUS, Vienna, 1556. A viol maker.
FELDLEN, MAGNUS, Vienna, 1722. I am inclined to
think this maker has only had a nominal existence on a
ticket fabricated by some one who did not know the
precise date of Magnus Felden's activity, and had not
caught the exact spelling of the name. Still, it is only
an inclination so to think. One can never be quite sure
about these names, apart from conclusive documentary
evidence. A great many of them are much alike, as in
the case of our own nomenclature, and I have, therefore,
preferred to leave them in the list without more than the
present comment.
http://www.ebooksread.com/authors-eng/james-m-fleming/the-fiddle-fanciers-guide-a-manual-of-information-regarding-violins-violas-b-ala/page-11-the-fiddle-fanciers-guide-a-manual-of-information-regarding-violins-violas-b-ala.shtml
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Porém:
No Universal Dictionary of Violin and Bow Makers, de William Henley:
FELDLEN, Magnus.
Attached to the Imperial Court at Vienna, 1622-1656. Viols, lutes, and a few violins.
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Contudo:
Carl Engel.
Musical myths and facts (Volume 1), p. 35
Author: Lütgendorff, Willibald Leo, Freiherr von, 1856-1937
FELDLEN, Magnus.
Attached to the Imperial Court at Vienna, 1622-1656. Viols, lutes, and a few violins.
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Contudo:
Carl Engel.
Musical myths and facts (Volume 1), p. 35
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Pra terminar:Author: Lütgendorff, Willibald Leo, Freiherr von, 1856-1937