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.
What is dengue fever? Dengue fever is an infectious viral disease caused by the bite  of infected mosquitoes.   Symptoms are sudden onset of high fever, severe headache, extreme  joint pain (â¦ thus the vernacular name, bone break fever).  Note that DF is comparatively rare and rarely fatal when it does  occur..engue fever is an infectious viral disease caused by the bite  of infected mosquitoes.   Symptoms are sudden onset of high fever, severe headache, extreme  joint pain (â¦ thus the vernacular name, bone break fever).  Note that DF is comparatively rare and rarely fatal when it does  occur. .