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.
1 Dengue fever is a disease caused by a family of viruses that are transmitted by mosquitoes. 2  Symptoms include severe joint and muscle pain, swollen lymph nodes, headache, fever, exhaustion, and rash. 3  The presence of fever, rash, and headache (the dengue triad) is characteristic of dengue fever.
Dengue fever symptoms. Dengue fever is a disease that features muscular aches and pains, fevers and often is accompanied by a fine petechial or pin-point rash. Severe cases of Dengue can progress to Dengue Hemorrhagic Fever (DHF) where the victim suffers from massive bleeding, frequently from IV sites, gums and rectum. People generally progress to DHF when they have been previously infected by Dengue, earlier in their life.