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I know that it's a "how long is a piece of string" question, but on average how long does it take before you stop making "strangled cat" sounds????
Ok, the length of a piece of string? From the centre it is precisely twice the distance to both ends,

so you've got an answer there, but the violin one is more difficult.
Lets make some assumptions:
1. You practice in a conscientious manner for 30 minutes every day. No waffling through things - you
practice scales, a study and perhaps one or two melodic pieces. You concentrate on tone production and intonation - the former of these being developed by correct technique of both the left and right hand.
2. You have a reasonable sense of pitch.
3. You make average, but steady progress over the next two to three years.
From this it's possible to assume that since you already play one instrument and can read music, you might have reached Grade 3 standard or perhaps a little higher. At Grade 3 I would hope your playing doesn't sound too much like a strangled cat, but in order to achieve this goal in the shortest possible time, concentrating on technique (both right and left arm) will help eliminate torturous sounds a lot earlier.
In order to improve your tone, try to think about what sort of sound you would like from the violin. Hear it in your head, then try to draw the bow across the strings and produce that sound. (Obviously quality of the instrument will have some bearing on the limit of its tonal quality).
At the moment (after so few lessons) you will rapidly switch back and forth from heavy handedness with the bow arm - producing a scratchy scraping noise - or not using enough evenly placed pressure - bow skids and the strings often squeak - neither of which are particularly pleasant tones. In addition, for optimum resonance of the strings always aim to keep the bow parallel to, and midway between, the bridge and the fingerboard.
Ask your teacher about studies suitable for tone and intonation. Sevcik studies are just one example for developing tone and intonation. In the meantime, playing open strings, aiming for a free and resonant tone, will greatly increase your bow arm control without having to worry about placement of the left hand fingers.
Good luck!