• The Eminence Delta 15 is a professional audio speaker.A Large Loud Speaker. image by daseaford from Fotolia.com
  
  The Delta 15 is a speaker made by the company Eminence, priced around $100. The Delta 15 is designed for musicians and other performers and it serves as a mid-bass or vocal wedge within a sealed enclosure cabinet, but also functions as a mid-bass or subwoofer in a vented enclosure.
  
  

Specifications

• Measuring at 15 inches, the Delta 15 is one of Eminence's largest Pro Audio speakers, smaller only than Eminence's 18-inch speakers. The Delta 15 sports a nominal impedance of 8 or 16 ohms, while the wattage output is 400 to 800, depending on usage. With a usable frequency range of 48Hz to 4kHz, this speaker provides decent power and range, especially considering the price. The magnet weighs in at 56 oz., and the coil diameter is 2.5 inches.
  
  

Mounting Information

• The recommended enclosure is 1.5 cubic feet for a seal enclosure and 2.9 to 5.7 cubic feet for a vented enclosure. Overall diameter comes in at 15.15 inches, while the baffle hole diameter is 13.77 inches. The mounting hole diameter is .25 inches. The depth of the speaker is 6.05 inches, and the net weight is 12.3 lbs.
  
  

Thiele/Small Parameters

• According to the Eminence test the Delta 15 recorded a resonant frequency of 40Hz. The DC resistance is 6.3, and the coil inductance for the speaker is .64mH. The mechanical Q tested at 8.05, the electromagnetic Q .57 and the total Q .53. The Delta 15's compliance equivalent volume is 9.56 cubic feet, and the peak diaphragm displacement volume is 233cc. The efficiency bandwidth product is 70, and the maximum linear excursion is at 2.7 mm. The maximum mechanical limit is 11.1 mm.
  
  

Construction Materials

• The Delta 15 is sold as the Delta 15A and 15B, with the difference residing in the material of the coil construction: the 15A features an aluminum coil, and the 15B is built with a copper coil. Both the 15A and B feature a coil former made of polyimide and magnet composition of ferrite. The basket material is pressed steel. The cone composition is paper; the cone edge is made of cloth; the dust cap is solid composition paper.