The key of G is small and the key of A is high-pitched, while the key of C and D is too big and too low. I feel that the key of F is more suitable. Those whose favorite songs range from low 5 to high 2 are usually more suitable to buy Big Fish, and those whose favorite songs range from low 3 to high 1 are mostly suitable to buy Niutou. For example, songs such as "Longing", "As long as I have you" and "One Cut Plum" are not suitable for these songs because it is difficult for a big fish to blow bass 3. However, the high notes of the bull head require more energy than the big fish, so it is not as easy to play the bull head as the big fish in "Wang Ning Mei". But when it comes to a song like "The Burial Flower Song" with a range from low 3 to high 2, you have to bite the bullet and brag, because it is much more difficult for Big Fish to play low 3 than for Niu Touchao to play high 2. ! It is best to play the big fish first, and then the bull head. Although the bull head is laborious, it is suitable for a wider range of songs. If you play it well, you can even play the bass 2, so "Dream Chaser", "Iron-Blooded Heart" and " Later, these songs containing bass 2 could be played without transposition. That is to say, if you practice well, you can play two octaves from bass 2 to treble 2! Of course, big fish and cow heads are relatively expensive. If you don't particularly like xun, it is recommended to buy a pen holder to play with. It is the simplest and most economical. If you don't play with it and throw it away, it won't be a pity.