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 Fever, headache, muscle pain, and rash may occur in both chikungunya and dengue. In addition, chikungunya is likely to give rise to severe and prolonged joint pains, which is one of the symptoms that distinguish it from dengue. Hemorrhagic manifestations are more likely in dengue fever.  Vector.