Subwoofer using a Large Advent cabinet?

[thedelihaus]

Have the chance to get a pair of bullnose Large Advents.

I'm considering using these nice cabinets as a subwoofer enclosure.

The Advent used a 10" driver in a 12" frame, so looks like I can use a 12" driver. Frame is 12 3/8" - to perhaps 12 1/2", does anyone have exact stock woofer frame size?

I'm not 100% sure of the Large Advent cabinet volume- but I'm guessing around 2 cubic feet. Does that sound right to you guys?

I'd prefer a sealed cabinet over ported.

I'd like to keep it an 8 ohm impedance.

I'll also be running a pair, and would use an active crossover designed specifically for subwoofers.

Will I need to add any type of internal crossover at all? Or just add the driver and polyfill, block the tweeter hole, and hook it up to the external active crossover and amp? Am I missing anything?

Again- goal is to use a Large Advent box, preferred to be sealed, 8 ohm load.

Here's a few drivers I'm considering so far...

 

[thedelihaus]

Dayton Audio RSS315HFA-8 12" Reference HF Subwoofer 8 Ohm

Overview:

Dayton Audio's Reference Series RSS315HFA-8 12" subwoofer utilizes the same low-distortion design as the rest of the series, but provides an 8 ohm alternative for increased connection and impedance-loading options.

Highlights:

Extensively vented motor eliminates power compression and allows quiet excursion
Lighter-weight black anodized aluminum cone minimizes moving mass
2-layer coil for reduced back EMF
Triple shorting-ring motor for ultra-low distortion
Optimized for large enclosures
Highest quality materials throughout for long-lasting performance

Product Details:

The Dayton Audio Reference Series subwoofers take the quality and performance of the much acclaimed RS line into the subwoofer realm. As with the rest of the Reference Series, the main focus of the RSS315HFA-8 12" driver is ultra-low-distortion. Second, third, and intermodulation distortion are kept extremely low by utilizing three magnetic short-circuit paths within the motor structure. A durable aramid fiber spider and extensive venting throughout provide quiet and uniform excursion. The black anodized cone, rubber surround, and custom basket give this driver a unique, high-end look. Choose this High Fidelity (HF) version for home speaker systems when your priority is clean, low bass and you are not restricted by cabinet size.

Specifications: • Power handling: 350 watts RMS/600 watts max • VCdia: 2-1/2" • Le: 1.60 mH • Impedance: 8 ohms • Re: 6.45 ohms • Frequency range: 25 - 1,500 Hz • Fs: 25 Hz • SPL: 84.5 dB 2.83V/1m • Vas: 2.67 cu. ft. • Qms: 2.94 • Qes: 0.64 • Qts: 0.53 • Xmax: 14 mm • Dimensions: Overall diameter: 12-3/8", Cutout diameter: 11-1/8", Depth: 5-3/8".



http://www.parts-express.com/pe/showdetl.cfm?partnumber=295-445

 

[thedelihaus]

Vifa NE315W-08 12" Subwoofer Speaker

Overview:

Peerless/Vifa's NE315W-08 12" neodymium subwoofer features a sophisticated, aerodynamic cast aluminum basket that also serves as a heat sink. The driver's Pentacone diaphragm technology and high-strength neodymium magnet provide incredibly deep, clean bass fundamentals.

Highlights:

Cast aluminum frame promotes motor cooling
Sculpted design improves airflow and reduces reflections
High-strength compact neodymium magnet system
Proprietary coated natural wood fiber cone with half-roll rubber surround
Long-throw 2" voice coil on strong, heat resistant titanium former
Copper pole piece cap for reduced inductance
8 ohm nominal impedance

Product Details:

The Peerless/Vifa NE315W-08 12" subwoofer's open cast aluminum basket design minimizes internal acoustic reflections and helps cool the neodymium motor. An additional heat sink supplements thermal dissipation. The cone is constructed of a coated natural wood fiber, with a butyl rubber surround designed by finite element analysis for linearity of performance. FEA techniques also contribute to the motor's copper cap, which reduces inductance and extends the driver's upper frequency range.

Specifications: • Power handling: 190 watts RMS/380 watts max • VCdia: 2" • Le: 0.54 mH • Impedance: 8 ohms • Re: 6.3 ohms • Frequency range: 20-1,000 Hz • Fs: 20 Hz • SPL: 86.5 2.83V/1m • Vas: 5.70 cu. ft. • Qms: 11.72 • Qes: 0.36 • Qts: 0.35 • Xmax: 9.35 mm • Dimensions: Overall diameter: 12.40", Cutout diameter: 11.33", Depth: 6.19".

http://www.parts-express.com/pe/showdetl.cfm?partnumber=264-1142

 

[thedelihaus]

Tang Band WQ-1858 12" Aluminum Subwoofer

Overview:

Tang Band's WQ-1858 subwoofer boasts 500 watts RMS power handling, an ultra-low 20 Hz free air resonance, and more than 13 mm of Xmax.

Product Details:

Tang Band's WQ-1858 subwoofer boasts 500 watts RMS power handling, an ultra-low 20 Hz free air resonance, and more than 13 mm of Xmax. It also features a reinforced aluminum cone and dust cap, rubber half-roll surround, under-spider venting, vented pole piece, bumped backplate, stacked ceramic ferrite magnets, and a strong die cast frame.

Specifications: • Power handling: 500 watts RMS/1,000 watts max • VCdia: 2" • Impedance: 8 ohms • Re: 6.8 ohms • Frequency response: 20-400 Hz • Fs: 20 Hz • SPL: 85 dB 1W/1m • Vas: 4.11 cu. ft. • Qms: 3.88 • Qes: 0.51 • Qts: 0.45 • Xmax: 13.3 mm • Dimensions: Overall diameter: 12.28", Cutout diameter: 11", Depth: 7".

http://www.parts-express.com/pe/showdetl.cfm?partnumber=264-897

 

[dumptruck]

I'm thinking those particle board cabinets are going to want some substantial bracing to have drivers like these running sealed in them. I may be back to check out the specs for the volume .

 

[djnagle]

Take a look at what I did to my Barzilay cabs. They are only partical board but now they are as solid as a rock.

http://www.audiokarma.org/forums/showthread.php?t=431549

 

[dumptruck]

If your goal is minimal carpentry, several sets of three 2x2 pieces arranged in H shapes will go a long way and can probably be snuck in without opening the cabinet. You'd want front-to-back and side-to-side placed at non-even fractions of the wall lengths.

 

[RayW]

These are in the order presented above and modeled in a 2cuft sealed box.

Looks like contestant #3 (Tang Band) is going to give the best performance but they're all within a couple of Hz so they're not going to be drastically different. All of them, for optimal flatness, would like a smaller box so the Qt goes down a bit but usually in this type of application that's a good thing.

 

[dumptruck]

Reviewers seem to be saying the TB is actually dual 4Ω coils?

 

[Spalls]

I have done a number of retrofits and used 2 X 2 furring strips to brace adjacent sides of older enclosures. With any luck you will be able to install them through the driver openings of the Advent baffle without too much trouble.

I have been using PE's HF 8-ohm 12-inch subwoofer for a couple of years now in a 2.1 cubic foot sealed enclosure and have been quite pleased with it. I installed it in a cabinet that I picked up at a garage sale. I lined the interior with half-inch plywood and used the 2 X 2 adjacent side braces as well. Pretty darn solid.

 

[RayW]

Something else that helps with cross bracing is to do it under tension. Cut your braces just a little long so you have to wedge them in and it will increase their efficacy at pushing resonances up out of the subwoofer passband. Alternatively you can go a little short and use screws from the outside to pull the sides in but that entails screws on the outside of the box which you may not like aesthetically.

 

[wbain]

Many years ago I bought a pair of KLH 7's from Salvation Army. Later I gutted one of them and bought a subwoofer driver and mounted it and sealed the box, removed the tweeter and midrange. My MC2100 drives it, both channels in parallel. Awesome.