The trick in building a vented box is to get the right size enclosure and the right size vent. You can't be too far off on either of these factors or your speaker's performance will suffer. In particular, using a too-small box or a too-high vent tuning frequency can eliminate bass instead of increasing it.
Symptoms, which usually begin four to six days after infection and last for up to 10 days, may include. 1  Sudden, high fever. 2  Severe headaches. 3  Pain behind the eyes. 4  Severe joint and muscle pain. 5  Fatigue. 6  Nausea. 7  Vomiting.
1 They usually include flu-like symptoms such as high fever, severe headache, pain behind the eyes, joint and muscle pain, nausea, vomiting and a rash. 2  It is common for some people to show no symptoms and most people recover from dengue fever after a few days.engue fever is a disease spread to humans by mosquito bites, and is caused by one of four types of dengue viruses. It can cause severe flu-like symptoms and in severe cases can be fatal.