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 affects the body by causing a high fever and flu-like symptoms. The virus infects your blood and causes a migraine-like headache, rash, achiness, queasiness, tiredness and fever.t can affect the blood, causing mild bleeding of the gums, and you may bruise easily. Once you have recovered from dengue fever, antibodies are left in your system, making your reaction to the disease more severe if you are infected a second time.