Down4Sound Down4Sound PRO-FAB Birch DIY Flat Pack - Quad 6.5-Inch Ported Subwoofer Enclosure Kit

Description Warranty Information 3 Reviews Description Build a powerful bass experience with the Down4Sound PRO-FAB Birch DIY Flat Pack, designed for four 6.5-inch subwoofers. This quad 6.5-inch ported subwoofer enclosure kit is perfect for DIY enthusiasts looking to add serious low-end punch to their setup. Crafted from high-quality birch wood, this flat pack provides durability, enhanced acoustics, and a precision-tuned ported design. Assembly is straightforward with pre-cut panels, allowing you to bring your custom audio project to life. Compatibility: Fits four 6.5-inch subwoofers Material: Premium birch wood for durability and rich sound quality Dimensions: 16.5" Depth x 37" Width x 9" Height Tuning Frequency: 36 Hz Cutout Diameter: 6 inches per subwoofer Terminal Rating: 2500W Internal Volume: 1.5 cubic feet (after displacement) Assembly Required: Yes – DIY kit with pre-cut pieces and detailed instructions included Ideal For: Audio enthusiasts wanting a customized, powerful bass solution ****ALL SALES ARE FINAL**** View All Close Warranty Information Warranty Information Your new Down4Sound product is covered by 1 limited warranty if purchased from Down4Sound or an authorized Down4Sound dealer. This warranty does not cover improper installation, accidental damage, misuse, abuse, improper wiring, operation of unit outside of listed specifications, or any product that has been modified or repaired by anyone other than Down4Sound. Your warranty covers defects in materials and/or workmanship ONLY and is not an insurance policy. The warranty only covers the original owner of the amplifier. All warranty returns must be accompanied by the original sales invoice or receipt. You must contact us to request an RMA number prior to sending any returns via the RMA request form on our websi te. You are responsible for the cost of shipping your product back to us for warranty examination. If your product is covered under warranty, shipping back to you will be at no charge to you – if your product is replaced/repaired outside of warranty you must pay for return shipping and repair bill prior returning of the product or if no defect is found you are required to pay for return shipping only. At the sole discretion of Down4Sound your product will be either repaired or replaced when it is being covered under warranty. In the event of shipping damage due to improper packaging on products being returned to Down4Sound the customer is liable for the cost of all damages, necessary repairs, or replacement. Be sure to properly pack your return! * Extended additional warranty purchased on amplifiers take in affect from the date of purchase and must also be stated on orginal sales invoice or receipt. Refund/Return Policy: https://www.down4soundshop.com/shipping-returns/ Down4Sound - Hours of Operation Monday 6am - 9pm PDT Tuesday 6am - 9pm PDT Wednesday 6am - 9pm PDT Thursday 6am - 9pm PDT Friday 6am - 9pm PDT Saturday 8am - 4pm PDT Sunday Closed View All Close 3 Reviews 4 Easy to build - Great packaging Posted by Jason Whichard on Oct 23, 2025 Assembling the box was straightforward, though it lacked the promised instructions. The packaging arrived safely from Nevada to Virginia. I used Gorilla Wood Glue and 1 5/8” #6 wood screws; the box’s predrilled holes made assembly easy. Printing the box drawings from the Down4SoundShop website helped. I added screws for the port pieces and flipped the etched panel inward, but the box still fit together well and performs as expected. 5 Flat pack sub box Posted by Jeramie Blake on Sep 20, 2025 very straightforward with accurate cuts and predrilled holes for quick assembly,just add carpenter glue 5 Great quality box Posted by Josh on Sep 03, 2025 I had 4 Skar EVL 6.5’s that I need a box for and I found this one. I was a little worried that it would get damaged in shipping because it was going across the country, but it was packaged very well and arrived undamaged. Assembly was a breeze, just needed wood glue and screws. It even had pre drilled hole. Also this thing slams, it sounds great. View All Close