Lo de la resina es algo que todavía me confunde en lo del cello (me confunden muchas más cosas, pero lo de la resina parece tan sencillo…). Nunca sé cuándo tengo que aplicar más y lo habitual es que me confunda: o demasiada o muy poca.
On average, you should apply a few (about 5) strokes of rosin before each practice session or performance. If you are practicing frequently or for many hours in a day you will find that you need more rosin more often. If you are not practicing much, you will go longer before more rosin is needed. If you are in doubt whether you need more rosin, then you should put some more rosin on the bow. If there is too much, the problem is easily handled by wiping the excess away, but students who routinely play with too little rosin learn bad bowing habits because they are playing with an unnecessary hardship they are not aware of. With too little rosin, the tendency is to squeeze the bow and push it harder than necessary into the string which can cause big problems with bowing in the long run.