There are two solutions. One is to open your mouth quickly after blowing a note and the airflow has not weakened, so that the remaining air in the mouth is retained in the mouth and is not exhaled, causing the cucurbit flute to remain in the mouth. The airflow suddenly stops, and the "gu" sound cannot be made. Another method is to quickly remove the mouthpiece from your mouth at the end of the piece.

Beginners usually hear the "gu" sound at the beginning or end of the sound. The reason why the "gu" sound appears at the head of the note is because when beginners play the cucurbit flute, they use the method of exhalation to send the airflow into the cucurbit flute, rather than the method of exhaling to send the airflow into the cucurbit flute.

When you exhale, the air head is soft and the strength is very weak, but it can already push the Hulusi to make a sound, so a "gu" sound appears. When the airflow continues to be strengthened, the Hulusi can It will make a normal sound, which is why the sound head appears "gu". Exhalation is the sound of the word "vomit" coming out of the mouth.

When the "spit" sound is made, the airflow is explosive. The airflow has a certain intensity and force from the beginning, and there is no soft air head when exhaling. When air is supplied to the cucurbit flute in this way, the airflow will initially reach the force and intensity required for the cucurbit flute to make a normal sound, so the "goo" sound at the head of the sound will not appear.

Extended information:

Hulusi playing techniques:

The performance of Hulusi is to a certain extent compared to bamboo flute, suona and other national wind instruments. It is simpler and does not have so many complicated techniques, which is also due to the limitations of its structure itself, but its sweet tone seems to be extremely expressive. The commonly used techniques in playing Hulusi are as follows:

1. Tone. Tongue sound is an important technique in Hulusi playing. There are three types of pronunciation: single pronunciation, double pronunciation and triple pronunciation.

①Single spit. Use the tip of the tongue to press against the front half of the palate (that is, the state before the word "vomit" is pronounced) to cut off the airflow, then quickly release the tongue, and blow out the breath. Through the continuous action of lifting and releasing, the airflow enters the mouthpiece intermittently, so that the effect of single blowing intermittently can be obtained and the process of single blowing can be completed. Single vomiting is usually marked with a "T" above the note. According to the needs of musical performance, single vomiting can be divided into two types: intermittent vomiting and continuous vomiting.

②Double vomiting. Double spitting is a technique used to complete rapid and continuous parts. First, press the tip of your tongue against the front palate, then release it to pronounce the word "spit". In short, after the word "vomit" is uttered, the word "ku" is immediately added, and the two characters "vomit bitter" are connected to form double vomiting. The symbol for double spitting is "TK".

③Three vomiting. Three vomiting is actually a combination of single vomiting and double vomiting in a certain rhythm pattern. The symbol is "TTK" or "TKT", which means "vomiting the bitterness" or "vomiting the bitterness".

2. Legato. Legato is one of the commonly used techniques. Suitable for lyrical and cantabile phrases or sections. It is represented by the symbol "⌒" (legato line). Except for the first sound in the legato line, there is no need to pronounce the rest of the sounds. When playing the legato line, the emphasis should be on coherence and smoothness.

3. Portamento. Portamento and its techniques are widely used in cucurbit performance, and its effect is smooth and gorgeous. The application of portamento technique can simulate the wiping effect on the human voice and string instruments. There are three types of portamento: up portamento, down portamento, and compound portamento.