In the introduction to their Italian translation of the Manas epic (Manas: L’epopea del poplo della steppa, Milan: Arnoldo Mondadori, 1997), Arnaldo Alberti and Begaim Nasserdinova contrast the Kyrgyz recitation of epic with that of other Turks by noting that the Tatars accompany recitation with a chatigan, a sort of zither. Their source here is certainly G. M. H. Shoolbraid’s The Oral Epic of Siberia and Central Asia, where we find on page 43:
In the performance of the [Kyrgyz] epic there is a large amount of mimicry and intonational play, and the story may be partly or totally sung. More than twenty melodies have been collected which the manaschi use. The accompaniment of Tatar heroic songs is generally by a stringed instrument, either a chatigan (a kind of zither), or a variety of lute. Radloff says that the ölöng, a recent type of lay, is accompanied, to some fourteen or fifteen melodies, by a two-stringed instrument resembling a balalaika, and this kind accompaniment is very common all over Central Asia. The kobuz, a three-stringed violin, is much in use, being described by Radloff and A. de Levchine (among the Kazakhs).
I had never heard of any such instrument as the chatigan among the Tatars before. There seem to be few references to it in the English-speaking world, to judge from Google Books and JSTOR. We find in Nora K. Chadwick’s article ‘Spiritual Ideas and Experiences of the Tatars of Central Asia’ from the Journal of the Royal Anthropological Institute of Great Britain and Ireland, Vol. 66 (Jul.–Dec., 1936), pp. 291–329:
In addition to the human voice instrumental music is very commonly used as a means of communicating with spirits. The instruments employed are the zither or chatigan (jädigän) and the reed pipe or pipes.
There is also mention of the instrument in the book written by Nora K. Chadwick with her husband H. Munro Chadwick, The Growth of Literature (Cambridge University Press, 1940). In the third volume in the chapter ‘The Oral Literature of the Tatars‘, we find a description of the instrument:
Finally some reference is necessary to the musical instruments in use among the Tatars, though we can only mention one or two of the commonest. There can be no question that for the accompaniment of narrative poetry stringed instruments of some kind or other are in general use. The most elaborate of this is perhaps the chatigan (jädigän). […] This instrument – a kind of zither – consists of a long cylindrical or oblong box without a lid, sometimes hollowed out of a single piece of wood. The box is, as it were, laid bottom upwards, and the strings are stretched along the outside of the bottom. There are generally five to eight strings in the modern chatigan, but in the past it was probably a more ambitious instrument, for in the poems the static description is ‘forty-stringed chatigan’. A chatigan brought by Czaplicka from Siberia is in the Pitt-Rivers Museum at Oxford. This specimen has six wire strings of equal length, variety of pitch being given by movable knuckle-bones of the reindeer, placed one under each string. The instrument is played by plucking the strings with the fingers of each hand. Probably the instrument is a rude imitation of a Russian gusli, though the shape is, of course, very different.
Well, that somewhat clears things up. Because of the mention of reindeer, we’re clearly not dealing with the Volga Tatars, and probably not even what are today called the Siberian Tatars, because the Chadwicks go on to recount how Maria Czaplicka had difficulties in buying her chatigan from a Sagay, that is, a speaker of Altay Turkic. Formerly these peoples were called Tatars in spite of their remoteness from Kazan’. But curiously, there are no search results in Russian-language scholarship for чатиган, leaving me puzzled about what the instrument is really called in that part of the world nowadays.