JBass 212×5

JBass 212×5

JBass 212×5

Project Category:
Guitar and Bass Speakers

Project Level:

Project Time:
8-20 Hours

Project Cost:
$100 – $500

Project Description:
The JBass 212×5 is a 2way bass guitar cabinet using dual 12″ woofers and 5″ midrange intended for power levels up to 400w.

Design Goals:
A better alternative to commercial offerings that do not account for cone breakup and distortion of larger drivers and cannot accurately reproduce the range of a bass guitar

Driver Selection:
Eminence S2012 woofers and PRO5MRN-8 midrange

Enclosure Design:
Ported enclosure, 6 cu ft ported via twin 4″ ports for an Fb of 40hz and f3 of 50

Enclosure Assembly:
Butt joint construction, braced between baffle and rear wall. Baffle is inset 1.25″ to account for the PE preformed mesh grill. Enclosure measures 31.5w 24h 17.75d.

Crossover Design:
The crossover uses 2nd order electrical filters on each side with the woofer using a damped circuit. Resulting crossover point is 2khz.

Tips & Tricks:
To inset the baffle, I mounted strips of hardwood on the inside perimeter. This allowed for additional glue surface. Additional strips were applied to the baffle with 1/8″ clearance to capture the preformed grill for a pressure fit.

The project is a definite success. The response transitions wonderfully between the drivers and gives a very clean presentation. In testing, I used an Adcom GFA555 (350W@4) and had no problems driving this to the amps limit. Punchy, smooth, with great sensitivity.

About the Designer:
I am an advanced designer of 10+ years.

Project Parts List:

Eminence Basslite S2012 Neo 12″ Bass Guitar Speaker 150W 8 Ohm
Neutrik NLT4MP speakON STX 4 Pole Male Chassis Connector Metal Housing
Formed Metal Grill Pair with 8mm Round Holes – 22.5″ x 30″ x 1″
Jantzen Audio 1.0mH 15 AWG Air Core Inductor Crossover Coil
Jantzen Audio 0.30mH 18 AWG Air Core Inductor Crossover Coil
Jantzen Audio 10uF 400V Crosscap Capacitor
Jantzen Audio 2.20 Ohm 10 Watt Audio-Grade Superes Resistor


Add yours
  1. 1
    Charles Morris

    I am the designer of the rig and want to add a few additional features and details. The cabinet has an Fb of 45hz and F3 of 42. The drivers are the Eminence S2012 woofers and PRO5MRN-8 midrange (nla).

  2. 2

    I am really interested in building this. I am unfortunately a beginner and would like to know if there are directions available to take me through wiring everything up?

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