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.
Symptoms Symptoms of typical uncomplicated (classic) dengue usually start with fever within 4 to 7 days after you have been bitten by an infected mosquito. These symptoms include: high fever, up to 105ÂºF, severe headache, retro-orbital (behind the eye) pain, severe joint and muscle pain, nausea and vomiting, and rash.reatment There is no specific treatment for classic dengue fever, and most people recover within 2 weeks. To help with recovery, health care experts recommend: The U.S. Centers for Disease Control advises people with dengue fever not to take aspirin.