Many thanks for your reply.
You've got to be careful that the crotchet single note bow isn't louder than the tied pair of crotchets bow i.e. faster bow shouldn't be louder, this may require an adjustment to the pressure used.
Indeed this was the very same problem which I encountered today. Maybe for now is normal given that today was the first time I was practicing bows in a 3/4 measure. So I will need to practice a lot more so that I might be able to produce a clean and not louder sound for the faster bow by the adjustment of the pressure on the strings as you said.
Many thanks for the help.
Not only you. When Silvestri became conductor of the Bournemouth Symphony Orchestra, it played the Natiional Anthem before every concert. We noticed that there was an unexpected and unwanted bulge in the sound at the quaver corresponding to the "scious" of "gracious", and wondered whether it was a Romanian accent that Silvestri had introduced, but then discovered it was there also when the orchestra had visiting conductors of other nationalities. We decided that it was the result of one bow per note and the difficulty of using almost as much bow on the quaver as the previous dotted crotchet had used.
When I play or conduct music by Elgar or Sibelius, I use their bowing, because they were both expert violinists and understood how bowing could help to produce the musical effects that they wanted. If the composer of "Evening Song" wants the effect that his/her bowing will produce, then I would wish not to perform it or to hear its performance. It will do well enough as an exercise illustrating the difficulty of bow management. To produce a good performance of it with string players of adequate technical competence, I would ask them to use one bow per bar, with hesitations in the bow movement to separate the notes, except for bar 15, so that 16 can have a downbow and a diminuendo. In particular, I would like the first beat of bar 13 to be the climax of the melody, and bar 12 should have a crescendo on an up bow, so that 13 can start at the heel.
My guide to bowing, paraphrased from expert string player and conductor, Christopher Adey: "It doesn't matter which way the bow is travelling; what's important is which bit of it is on the string."