Sundown ZV.7 15"

The Sundown Audio ZV.7 15" is a high-performance subwoofer designed without compromise for systems that require massive low-frequency bass, high power headroom, and extreme cone excursion. The seventh generation of the Z Series is built on Sundown’s massive Mega-Platform and combines an exceptionally powerful motor assembly with a long-throw voice coil and a cooling system designed to handle high loads.

At the heart of the ZV.7 is the massive, four-layer stacked magnetic drive with a motor diameter of approximately 26.5 cm and a magnet stack height of about 10 cm. Compared to the ZV.6, the motor has been significantly further developed. The high power factor and the design optimized for linearity ensure that the subwoofer operates in a controlled manner even under extreme excursion.

The 4-layer aluminum round-wire voice coil has a diameter of approximately 8.4 cm and is mounted on a solid aluminum voice coil former. A sophisticated ventilation system—featuring airflow guidance around the pole piece, multiple cooling channels, 16 air gap openings, and an upper pole plate with additional slots and drill holes—aids heat dissipation during prolonged heavy-duty operation.

With a linear Xmax of 42 mm in one direction, the ZV.7 offers enormous excursion reserves. The mechanically possible excursion is as high as 77.5 mm in one direction. This makes the 38-cm subwoofer particularly well-suited for high-performance bass-reflex and bandpass systems with very low-frequency tuning.

Technical Specifications

• Subwoofer size: 38 cm (15")
• RMS Power Handling: 3,500 watts
• Peak Power Handling: 7,000 watts
• Voice coil: 4-layer aluminum round-wire voice coil
• Voice coil diameter: approx. 8.4 cm
• Voice coil former: aluminum
• Linear stroke Xmax: 42 mm, single-sided
• Mechanical deflection Xmech: 77.5 mm, on one side
• Effective membrane area Sd: 1141.9 cm²
• Motor design: 4-layer stacked magnet system
• Diameter of the magnetic structure: approx. 26.5 cm
• Height of the magnet assembly: approx. 10.0 cm
• Faraday Ring: 9 mm Magnetic ID Faraday Ring
• Versions: D1 with 2 × 1 Ω or D2 with 2 × 2 Ω
  
  

T/S Parameters – ZV.7 15 D1

• Voice coil impedance: 2 × 1 Ω
• DC resistance Re: 1.96 Ω
• Resonance frequency Fs: 30.82 Hz
• Mechanical Grade Qms: 5.919
• Electrical quality Qes: 0.412
• Total quality Qts: 0.385
• Equivalent volume (Vas): 33.27 liters
• Mass in motion (Mms): 606.05 g
• Elasticity (cm): 43.99 µm/N
• BL Force Factor: 23.647 Tm
• Voice coil inductance Le: 1.83 mH
• Sensitivity: 91.58 dB / 1 W / 1 m
• Effective membrane area Sd: 1141.9 cm²
• Xmax: 42 mm
• Xmech: 77.5 mm
• RMS Power Handling: 3,500 watts
• Peak power rating: 7,000 watts
  
  

T/S Parameters – ZV.7 15 D2

• Voice coil impedance: 2 × 2 Ω
• DC resistance Re: 3.84 Ω
• Resonance frequency Fs: 30.40 Hz
• Mechanical Grade Qms: 5.607
• Electrical quality Qes: 0.364
• Total quality Qts: 0.342
• Equivalent volume (Vas): 35.56 liters
• Mass in motion (Mms): 582.89 g
• Elasticity (cm/m): 47.02 µm/N
• BL Force Factor: 34.260 Tm
• Voice coil inductance Le: 3.72 mH
• Sensitivity: 89.32 dB / 1 W / 1 m
• Effective membrane area Sd: 1141.9 cm²
• Xmax: 42 mm
• Xmech: 77.5 mm
• RMS Power Handling: 3,500 watts
• Peak power rating: 7,000 watts
  
  

Dimensions

• Outer diameter: approx. 39.40 cm
• Installation diameter: approx. 35.38 cm
• Installation depth: approx. 35.41 cm
• Motor diameter: approx. 27.43 cm
• Subwoofer displacement: approx. 8.21 liters
  
  

Enclosure Recommendation – Bass Reflex

• Recommended net volume: approx. 113.3 liters
• Recommended tuning frequency: 32 Hz
• Recommended port area: approx. 387 cm²
• Enclosed housing: not recommended
  
  

Enclosure Recommendation – 4th-Order Bandpass

• Enclosed chamber: approx. 56.6 liters
• Ventilated compartment: approx. 169.9 liters
• Recommended port area: approx. 774 cm²
• Recommended port length: approx. 20.3 cm
  
  

Special Features

• Highly durable 38-cm high-excursion subwoofer
• Massive Sundown Audio Mega-Platform
• 3,500 watts RMS power handling capacity
• Enormous linear diaphragm stroke of 42 mm in each direction
• High-performance, quad-stacked magnetic drive
• 4-layer aluminum voice coil
• Specially designed “Fat Wire” winding for high power handling capacity
• Sophisticated cooling system for the voice coil
• 16 ventilation openings in the air gap area
• Six additional cooling channels on the pole core
• Slotted and cross-drilled upper pole plate
• 9-mm Faraday ring for improving inductive linearity
• FEA-optimized engine design
• Particularly suitable for bass-reflex enclosures tuned to a low frequency
• Designed for high-performance SQL, demo, and SPL systems