DIY Plans for Speaker No. 1815 --- Large DIY 15" 2-way Monitor using SB Audience Products

By purchasing these plans you will automatically receive via email the required drawings, crossover schematic, and 3D CAD files to construct speaker system No.1815.

Includes

• PDF cabinet drawings 
  • Assembly drawings 
  • Individual part drawing
• Nested cutting layout on sheet of plywood 
  • Includes options for horizontal or vertical grain direction 
• Crossover Schematic 
  • Listed component numbers 
    • Solen air core inductors 
    • Mundorf Mcap Supreme Capacitors 
    • Mundorf M-Resist Resistors 
    • Components available from Madisound (USA) or TLHP (France) 
• Assembly drawing for horn (PDF) 
• Assembly drawing for compression driver 
  • Requires clamp bars which allows compression driver to operate open back (Dipole radiation) 
• 3D CAD Files for horn 
  • Iges format (for CNC Machining) 
  • STL format (for 3D printing) 
    • Includes extra model which is broken up into pieces for smaller printers

The 3D CAD files are provided to CNC or 3D print the ES-600 Biradial Horn No.1978 along with the .STL file to 3D print the compression driver rear clamp bars. The rear clamp bars are critical to the overall sound quality.

The ES-600 Biradial Horn No.1978 is available from us in either finished state or rough machined which requires sanding. Alternately you can CNC machine the horns yourself if you have the appropriate CAM software and machine. The horns can also be 3D printed if you have a 3D printer bed measuring 40cm x 40cm. 

Click image below to enlarge. 

Introduction Video click HERE.

Technical deep dive video click HERE.

Details 

• 95dB sensitivity (Anechoic) or 102dB (Approximate in-room)
• 15" 2-way design using 600Hz crossover (3rd order slopes) 
• SB Audience Bianco 15OB350
• SB Audience 65CDN-T 1.4" compression driver 
• ES-600 Biradial Horn No.1978 
  • Purchased from us 
    • Finished 
    • Raw CNC machined (requires sanding)
  • Or made by you 
    • 3D print using STL files
    • Or CNC machine in your own workshop (DIY) using .Step files 
• Compact physical size including corner placement option
• Aesthetically pleasing 
• Off the shelf components that are easily available 
• High output SPL and low distortion 
• Suitable for audiophile two channel or high end home theater as L/C/R 
• Crossover optimized to audiophile listening and flat frequency response 
• Clean, tight bass that is free from 'boxiness'  or 'boominess' 
• Easy to construct cabinet

A more detailed blog post on this product can be found HERE. 

Speaker Plans 

The plans include assembly and detail drawings along with the passive crossover schematic to construct the crossover. 

The bass cabinet should be positioned for best stereo imaging. We suggest at least 30cm from the front wall and 60cm from the side walls. The speaker can be placed in the corner but it is not recommended for best imaging. 

For aesthetic purposes the woofer is rear mounted into the enclosure. This requires that the side panel be removable on the cabinet. This is optional of course. The driver can be front mounted if you'd like and simplifies cabinet construction even further, but means an exposed driver frame and doesn't look as clean as the rear mounted configuration. 

Cabinet Material

The cabinet material is standard 18mm thick birch plywood. You can also use marine ply or apple ply as well. We do not recommend MDF. 

Cabinet Stuffing 

The cabinet is to to be stuffed 100% full of polyfill (pillow stuffing). We suggest keeping the pillow intact and stapling in place internally ensuring the pillow does not touch the woofer diaphragm. 

Crossover 

The crossover schematic includes suggested part numbers which have been optimized for the best sound quality. The final tuning of the crossover was based on extensive music listening to a variety of tracks. Acoustical measurement was used to verify a flat frequency response, but it was not the end goal, even though the response is very flat, the end goal is excellent subjective sound quality.

The inductors should be sized to provide the lowest DC Resistance possible (DCR), however as a rule of thumb the total DCR should be kept below 1ohm for each inductor in the circuit. 

Minimum inductor size: 

Air Core: 16 ga. (1.25mm wire dia.)

Iron Core: 18 ga. (1.00mm wire dia.) 

For European customers please refer to TLHP's BL125 series from Mundorf which is a 1.25mm wire diameter air core (16awg). Please refer to Mundorf's size chart here. 

Testimonials

Customer testimonial on the V4 crossover “A quick feedback on your crossover design V4 for the 1815 loudspeaker ("Speaker No.1815 Passive Crossover Schematic REV04.png").

I built the crossover from (not even top quality) parts I had available at home and am very chuffed with the results. The integration between horn and woofer seems really good now, and soundstage precision has increased.

I wish I were this good with the active crossovers that I had implemented in the Hypex modules, haha.