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.
Dengue. Dengue refers to a tropical disease caused by four different types of virus. It is usually transmitted by mosquitoes and the common symptoms include fever, headache, muscle and joint pains and skin rash.iagnosis. Diagnosis of dengue is usually done based on patientâs symptoms and physical examination, especially in endemic areas. A probable diagnosis is made on the findings of fever with the following symptoms: nausea and vomiting, rash and generalized pain.