Welcome to JHS Audio. Feel free to browse through the links below.

New stuff is towards the bottom, and dates indicate updates to pages.


Past Systems Generally Useful Info Other Stuff
Ariels Links Audio Items for Sale / for Free - 101203
4-way horn stack Horn Design - 2/7/06 150Hz Tractrix horn
Unity horn w/ vented sub Wavefront Measurement in a Horn Bend 27Hz Horn Subwoofer
3-way Unity horn FEM's of Bass horns in Various Orientations in Rooms Fostex FE83 in a SS pot
Unity horn w/ dipole midbass Some FEA's of Waves in Curved vs. Reflector Horn Bends Unity horn - 10/28/05
5-way mono horn stack A Budget Speaker Measurement System MCM Horn sub (built by Tim Moorman)
3-way horn stack:
27hz horn, EVM12L in 75hz horn,
various 1" CD's on a 500hz tractrix
Stored Energy Measurements 40Hz Horn
JBL Sub1500 in sealed box,
conical midrange w/ 4x 5" drivers,
JBL2470 on 500hz tractrix,
Fostex FT17H
H and U baffle dipoles - 12/30/04 Metal Working projects - 10/31/08
Temporary apartment system:
Fostex FE168E Sigmas on open baffles
Polar maps of various horns - 7/7/05 Horn subwoofer using two HL10's
0511 - 0804 house system Fostex FE168E Sigmas
on open baffles- with JBL Sub1500 in
sealed box, mains time delayed to match sub
LeCleac'h and Conical horn performance comparison DIY Super tweeter - 12/18/04
Starting a new die - 2/14/05
More die - 2/26/05
071208 - basement system -
4x HL10 in 30hz EBS vented box to 200hz,
40 degree conical up to 1.7kHz,
Radian 475 on 500hz tractrix,
DSP crossover, eq and time delay -
0-60 degrees in room, 0-60 normalized
0-60 normalized, 1kHz crossover w/ better power response
Directivity index w/ 1kHz crossover
System with Fostex FT17H added
Directivity index with FT17H added
(crossover at 10kHz still needs work, but DI comes down in the 10kHz-20kHz octave)
Headphone measurements:
Measurements are taken on a calibrated B&K HATS (head and torso simulator).
Measurements are converted to diffuse field or free field equivalent responses depending on which it looks like the headphones were designed for as noted on the graphs (so a flat response is subjectively flat).
Sennheiser HD580, channel difference, distortion
AKG K26P, distortion
Grado SR60, channel difference, distortion

If you want your headphones measured, send me an email. I'll measure them for free and send you the data if you pay for shipping both ways.
DIY 6.5" shorting ring (~1.5" diameter) - 10/3/06
081202 - Bedroom speaker - Unity horn with B&C DE25,
Eminence Beta 8's on top of sealed JBL M151 and dual
MCM 10" woofers vented with DSP crossover.
Relative response at various angles covering the entire listening area
. Vacuum bagging an amplifier bracket - this bracket is to hold an amplifier under the seat of my car. It's made of foam, fiberglass and carbon fiber, and conforms to the shape of the floor of my car.
The amp installed
101204 - Garage speaker - Unity horn with 4x 5" MCM midranges and Radian 475 compression driver mounted on top of a vented cabinet with 4x Eminence HL10 drivers.
Powered by a 16 channel DSP amplifier with cnc machined front panel.
Driven by a Sansa clip mp3 player.
Measured and eq'd outside using Holm Impulse and ground plane measurements.
. Rigging a Tannewitz table saw / building a gantry crane - 4/9/06

Some pictures of the saw
. . CNC router - 7/1/09 - I designed and built this from 80/20 framing. It has a 4'x4'x6" cutting envelope.
Here's a gallery of pictures from when I rebuilt my router after moving it.
I built the router to cut this horn and others that I'm working on.
Parts for the horn, profiled in a sheet of MDF.
The same parts after 3D milling and assembly, but before sanding.
The partially sanded LeCleac'h horn with a bass cabinet.
More horn pics
A battery bracket for my motorcycle, also cut on my router.
Thread milling a filler neck for my Ducati's expansion tank - Youtube video link - 5/8/2011.
Building a vacuum chuck and using it to mill a pcb - 9/25/2011
. . Hand held spindle sander - 4/13/2010 - my tool of choice for sanding horns. I designed and built this using a 300W (0.4HP) AC servo motor and parts from a Grizzly spindle sander. Speed is infinitely variable. I still need to contour the motor mount on the cnc when I have time.
. . Goto prototype system developed on request - 4/24/2010
I designed and fabricated the back loaded bass cabinets,
the high frequency driver stands, the aluminum stand
and wooden cradle for the mid frequency horn, a
high frequency driver alignment guide to ease setup as well
as developing a 4 way passive crossover for the system.
Drivers used are the SG-160, SG-370DX, SG-570, and SG-38WNS.
Here are a few pictures:
Bass cabinets during construction
Some outdoor testing
Getting ready to weld a mid horn stand
The stands awaiting some polishing
Finished system setup for listening
Crossover is setup on top of the bass cabinets for testing
Mid support stand - can be aimed vertically via the threaded rod
Mid horn cradle
High frequency horn stand
The crossover network
Alignment guide
As shown, there is no finish applied. The stands were not fully
polished as they were to be painted as well.
. . Oris horn extensions for JBL 2482's - 9/20/11 - I designed and built a pair of extensions for Oris horns for a friend. They'll let him put reversed JBL 2482 compression drivers on his Oris horns. I designed these in Pro/E and cut the parts on my cnc router.
. . My Ducati 748 (non audio)
Working on my 748, March 2011
Ducati 748 weight information
Ducati single phase alternator tools for sale

Copyright 1999-2012, John H Sheerin

Feel free to email me at with any questions or comments.