Speaker No.1630 Plans

Speaker No.1630 has been carefully optimized to provide the ultimate in resolution and clarity in a small foot print size.  Don't be fooled by it's modest driver compliment!  We've directly compared this speaker against the best from AER and this speaker came out a clear winner even according to audiophiles who have visited our listen room.  The speaker provides a holographic soundstage thanks to it's point source coherent sound.  Gone is the shouty sound associated with poor design implementation.  This speaker has a wonderfully full and rich sound character. 

See our YouTube Video on the No.1630 Speaker. 

By purchasing these plans you will automatically receive the PDF drawings required to built this small floor standing speaker.  

Includes 

• All funds in USD currency 
• Plans automatically emailed after purchase 
• Includes PDF assembly and detail drawings 
• Includes passive crossover electrical schematic 
• Basic construction techniques (no angle cuts)

Design Features

• Small footprint (214mm wide x 900mm tall x 202mm deep)
• Double layer stepped front baffle 
• 12mm baltic birch plywood construction 
• Dual passive radiator (one for woofers, one for fullrange) 
• Separate enclosure for fullrange driver 
• 4" Fostex FE108NS driver 
• Dual 5" Scanspeak woofers 
• Frequency response 40Hz-19kHz (+31kHz with optional T96A super tweeter) 
• 90dB sensitivity @2.83V 
• 8ohm 

To purchase the drivers and crossover components as a kit click HERE. 

Specification Sheet click HERE. 

Application

This speaker is specifically designed for near field listening which is characterized by low to moderate listening levels using a listening distance of 2m or less.  The final tuning of the speaker has been tailored to provide a rich and full sound even at lower listening levels.  In other words, the speaker is tuned with loudness compensation built in.  This means that the bass, and mid-bass, is +4dB higher than standard designs. The speaker has been optimally tuned for a listening level of around 75dB.  Although the speaker is perfectly capable of playing up to 90dB at 1m with less than 0.30% distortion across it's bandwidth.  Piano in particular comes through with a rich and full body sound.  

Speaker No.1630 is specifically designed for the single driver enthusiast that values coherent point source sound but doesn't want the "shouty" sound character which is so common in other designs. 

Using the new Fostex FE108NS provides razor sharp transient detail along with a lively sound character through the vocal range.  The design retains the single driver sound allowing you to hear far into the soundstage.  The Fostex driver operates in it's own bass reflex enclosure using a unique rear facing passive radiator.  Internal diffraction panels further breakup internal standing waves improving clarity. 

The dual 5" Scanspeak woofers operate well into the mid-bass region eliminating any baffle step compensation requirements for the Fostex.  This lowers distortion on the Fostex an retains a purist approach of no crossover components in the fullrange driver's signal path. 

The new Fostex T96A super tweeter can be added as an option.  This widens the off-axis coverage which has the affect of creating greater soundstage width in the upper treble.  

Construction

Speaker No.1630 can be built using very basic construction techniques.  All cuts are right angles.  This makes the design accessible to even the most amateur woodworker!  One pair of speakers can be made from one sheet of plywood measuring 12mm thick by 48" x 96" (1220mm x 2440mm).  

Fostex FE108NS

The Fostex FE108NS is a new offering from Fostex that follows after the success of the limited edition SOL series.  NS stands for "New Sol" and adopts the copper cap on the pole piece to lower distortion.  This is a truly high-end sounding full range driver which uses a treated cloth pleated surround, and dual layer paper cone, and damping material behind the dust cap.  

Scanspeak Discovery 15W/4434G-00

The use of these specific drivers allows for a very high sensitivity of 90dB with a tube amp friendly 8ohm load.  Bass extension reaches 40Hz with ease.  The woofers are made in Denmark and feature aluminum demodulation rings for low distortion.  Our testing shows intermodulation distortion through the bass is an astonishingly low -50dB(0.30%) even up to 90dB SPL@1m. 

Passive Radiators 

Using passive radiators eliminates many of the issues found with traditional port tubes.  

Fostex T96A Super Tweeter (optional)

The plans include the crossover schematic to properly integrate the Fostex T96A super tweeter.  This special tweeter extends the frequency bandwidth to above 30kHz.  The tweeter also widens the off-axis coverage in the upper treble.  This has the effect of creating a wider soundstage.  This tweeter is optional and can be an upgrade path down the road.  Based on our extensive listening tests it is recommended to use the Fostex non-inductive copper foil PPTA film capacitors which are detailed out in the plans.