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 - 8/9/07
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
11/05 - 4/08 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.
. . Rigging a table saw / building a gantry crane - 4/9/06
. . CNC router - 7/1/09 - I designed and built this from 80/20 framing. It has a 4'x4'x6" cutting envelope.
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.
A battery bracket for my motorcycle, also cut on my router.
. . My Ducati 748 (non audio)

Copyright 1999-2009, John H Sheerin

Feel free to email me at jsheerin79456@123gmail.com with any questions or comments.
(remove the numbers 456 and 123 from the address - sorry, but I'm trying to cut down on my spam intake)