I have three books describing double bass positions but each of them are different. York Studies for Double Bass describes second position as first finger on B flat, on the G string. The Study of Orchestration (Samuel Adler) describes second position as first finger on B natural. Practical Tutor (Adolf Lotter) has explanations of ordinary position and medium positions along side traditional positions. I was wondering what, if any, systems of left hand positions to use. I have not been playing long and my teacher uses Simandl technique so Rabbaths positions are not an option for the time being. I realise that any of these systems can be used if you are consistent with their application but is there one that is more popular? Thanks for any help.