----- Experience in your own room the magical nature of stereo sound -----

 

 

What's new

 

LX - Store

 

BLACKLIST

 

Conversations
with Fitz

 

OPLUG
Forum

 

Basics

The Magic in 2-Channel Sound

Issues in speaker
design

Dipole models

Active filters

Amplifiers etc

Microphone

FAQ's

Loudspeakers

Crossovers

Room acoustics

Stereo Recording and Rendering

Audio production

Conclusions

 

Projects

Your own desig

LXmini

LXmini+2

LXstudio

LX521.4

LX521
reference

ORION
challenge

ORION-3.4

PLUTO-2.1

WATSON-SEL

PLUTO+
subwoofer

THOR
subwoofer

PHOENIX
dipole speaker

Three-Box active
system (1978)

Reference
earphones

Surround
sound

Loudspeaker
& Room

 

Resources

Publications

Sound recordings

Links

Other designs

My current setup

About me

Site map

 

HOME

 

------------------
Digital Photo
Processes

 

------------------
The
Sea Ranch

 

------------------
My Daughter
the Jeweler

 

What's new

 

LX - Store

 

Conversations
with Fitz

 

OPLUG
Forum

 

 

 

Site map

Concepts ... Projects ...   Products ... Resources ... Conclusions ...

 

Concepts ...

Stereo Recording
and Rendering
- Stereo Recording & Rendering - 101
- Acoustics vs Human Hearing
- Subjective evaluation of phantom acoustic scenes
- Making a SACD with the Budapest Orchestra 
- Room optimized stereo reproduction
- Sound Reproduction
- Recording what we hear
- Experimental Results
- Theory - Mapping from recording to playback
- Stereo Recording Angle
 
Loudspeakers - Loudspeakers - What should they do?
- Design of Loudspeakers
- A dozen ways to evaluate a loudspeaker
- Accurate performance of a stereo sound system
- Sound quality glossary - sd-qlty.gif
Crossovers - Crossovers
- Linkwitz/Riley crossovers 
- Active Filters
- L/R Active XO
- L/R Passive XO
- Shaped toneburst test
Room acoustics
- Room acoustics
- Room modes, etc. - modes1.xls
- Radiation patterns - radpat1.gif
- SPL inside small enclosure - enclosure-spl.gif
Issues in speaker design

A - Acoustic absorption and acoustic resistors
B -
Frequency response of open baffles
C -
Dipoles below the Schroeder frequency of a room
D -
Room and baffle reflections
E -
Line sources
F -
Group delay and transient response
G -
Multitone distortion
H -
Suggestions and hearing
I -
Digital crossovers
J -
Doppler distortion
K -
Room response equalization
L -
H-frame and U-frame open-baffle woofers
L2 - H-frame and U-frame open-baffle woofers
M - Investigation of energy storage
M2
- Investigation of energy storage
N -
 Mounting a driver to a baffle
O -
Unreasonably high distortion in midrange drivers?
P -
 Estimate of Le(x) induced distortion at high frequencies

Q -
Estimate of Le(i) induced distortion at high frequencies
R -
Recommended study material about distortion in loudspeaker drivers

S -
Dipole and monopole woofer response
T - Separate woofer crossover and offset
U - Woofer level setting
V -
Crossover topology mistakes
W -
Accurate performance of a stereo sound system
X -
Spatial distortion in audio
Y - Triggered burst measurements of tweeters
Z - Accuracy, spatial distortion and plausibility of the auditory scene
A2 - High-frequency down-shelving for ORION-3
B2 - What is the optimum polar response for a loudspeaker?
C2 - L-07 Dipole loudspeaker
D2 - Phase shift due to dipole D & effect upon xo

- Doppler distortion - doppler1.gif

- Different view of Doppler distortion - doppler2.gif

- SPL dependent driver behavior - SPL-dependent.xls

- Room absorption - T60-absorption.xls

- Standing waves - dipole-impulse-2.ckt 

- Standing waves - dipole-freq-2.ckt

 

Projects ...

LX521 monitor - Description
- Supplies
- FAQ
- Photos/Comments
- Baffle assembly
- DSP challenge
- Listening_distance.xls
ORION challenge - The challenge to build a state of the art
   loudspeaker yourself
- What is involved in building the ORION?

- Supplies and materials to build ORION
- Promotion 
- THOR-ORION crossover/equalizer
- Photo Gallery
- ORION reviews 
- Analog Signal Processor - ASP
- Frequently asked questions
- Revision 0.1 of the ORION
- ORION++
- ORION-3 
- ORION-4
- ORION crossover/equalizer response -
   orion-xo-eq.gif

- Content of documentation - orion-doc.gif

ORION-3.4 - ORION-3  
PLUTO-2.1 - Introduction
- Specifications and operating characteristics
- Construction of the enclosure
- Power amplifier, crossover and equalizer
  electronics module
- Supplies and materials to build PLUTO
- Photo Gallery
- Adding subwoofers to PLUTO
- PLUTO-2.1
- Pluto-3
 
WATSON SEL - WATSON Stereo Enhancement Loudspeakers - modes1.xls
PLUTO+
subwoofer
- Adding subwoofers to PLUTO
-
Woofer ASP
- Supplies to build the subwoofer
- Closed box woofer design - closed-box1.xls
   Closed-Box-WithDriverDb.xls
THOR subwoofer  - Build your own subwoofer
- Subwoofer design estimates
- Subwoofer design
- Woofer measurements
- Frequency response equalization
- THOR-ORION crossover/equalizer
- Supplies and materials to build THOR 
- Electrical and mechanical limits to sound output
  from a closed box woofer
- Closed box woofer design - closed-box1.xls
   Closed-Box-WithDriverDb.xls

- SPL inside box - enclosure-spl.gif

- Distortion of air compliance - air-distortn.gif

- s-plane for highpass filter - 12db-hpf.gif

- Content of documentation - thor-doc.gif

 

 

PHOENIX
dipole speaker

- Build your own open-baffle loudspeaker system - Commercial use of the PHOENIX technology
- Loudspeaker System Design
- Speaker stand and grill frame - stand1.gif
- Main Panel - Mechanical construction and drivers
- Distortion test of midrange & tweeter drivers
- Midrange frequency responses - mid_rsp.htm
- Audibility of allpass crossover phase distortion 
- Audibility of group delay distortion - phs-dst2.htm
- Dipole Woofer - Mechanical construction 
  and drivers 
- Excursion limited SPL - theory.gif
- Excursion limited SPL - spl_max1.xls
-
Dual voice coil wiring - dvc-wrg.gif
- Dipole Woofer 2 - Alternate drivers 2
- Dipole Woofer 3 - Alternate drivers 3 
- Crossover/EQ - Line level electronic crossover
  and equalizer
- Crossover circuit - 38xo_eq1.gif
- Crossover response - xo_eq2.jpg
- Shelving high-pass - shlv-hpf.gif
- Shelving low-pass - shlv-lpf.gif
- Active inductor 1 - inductr1.gif
- Active inductor 2 - inductr2.gif
- Active L-R crossover - xo12-24.gif
- Linear dB gain control - gain-adj.gif
- Delay correcting filter - allpass.gif
- Attenuator with Rout spec - attnrout.gif
- Input impedance measurement - input-r.gif
 -3 dB/dec circuit 1 - 3db_buff.gif
 -3 dB/dec circuit 2 - 3db_oct2.gif 
 -3 dB/dec response 1 - 3db_oct1.jpg
- Remote preamplifier - preamp1.gif 
- Power amplifier - 3886amp.gif 
- Power supply - 3886pwr.gif  
- Room EQ - phn-room2.xls  
- Supplies - Printed circuit boards - ASP blockdiagram
- System Test - Electrical and acoustic system test - Crossover/EQ response - x1.gif - x2.gif
- Main panel response - p1.gif - p2.gif - p3.gif
  - p4.gif - p5.gif - p6.gif - p7.gif - p8.gif
  - p9.gif - p10.gif
- Woofer response - w1.gif - w2.gif - w3.gif
  - w4.gif - w5.gif
-
Shaped tone-burst generator - brst_gen.gif
- Shaped tone-burst -
shaped tone-burst
- Blackman window data - blkman_4.prn 

- Shaped tone-burst sound -
1kblkman4.wav 
-
Multi-burst sound - 100mbst4.wav   
- 10-cycle burst data file - cos_10.prn
- Microphone - Microphone modification - microph1.gif
- Stereo microphone - microph2.gif
- Peak detecting mic. preamp. - mic_pk.gif
- Linear dB gain control - gain-adj.gif  
- Design Models 
  A   - Two point sources of opposite polarity model
  A1 - Dipole equalization
  B   - Open baffle loudspeakers
  B1 - "Compound dipole" woofer model
  C   - Dipole woofer equalization
  C1 - Notch filter design
  C2 - 6 dB/oct slope correction
  C3 - Equalization of low Qt woofer
  D   - Midrange dipole equalization
  E   - Midrange to tweeter crossover
  F   - Midrange to woofer crossover
  F1 - Woofer level setting
  G   - Level adjustment controls
  H   - Psycho-acoustic 3 kHz dip
  I    - Voltage sensitivity of an active system
- Excursion limited SPL - spl_max1.xls
-
Excursion limited SPL - theory.gif
- Active inductor 2 - inductr2.gif
- Crossover circuit - 38xo_eq1.gif
- Shelving low-pass - shlv-lpf.gif
-
Pole-zero transform circuit - f0Q0fpQp.gif
-
Closed box response vs. impedance - f0Q0.gif
- Crossover/EQ response - x1.gif
- Prototypes  
  A - Open-baffle woofer - PW1
  B - Woofer crossover to existing midrange - PXM1
  C - Mini open-baffle speaker - PMT1
  D - Main panel with passive crossover to 
  tweeter - PMTM1
  E -
Crossover/Equalizer for passive dipole woofer
  F - Transition to fully active systems
- Woofer EQ & LR2 passive LPF - w-xo-lp1.gif
- Woofer EQ & LR2 active LPF - w-xo-lp2.gif
- Midrange LR2 highpass filter - m-xo-hp2.gif
- PMTM1 low frequency EQ - pmtm-eq1.gif
- R-L-C Zobel & RF termination - pmtm-zob.gif
-
Excursion limited SPL - spl_max1.xls
- Active Filters  
  1 -  Buffer stage
  2 -  12 dB/oct Linkwitz-Riley crossover
  3 -  24 dB/oct Linkwitz-Riley crossover
  4 -  Delay correction
  5 -  Shelving lowpass
  6 -  Shelving highpass
  7 -  Notch filter
  8 -  6 dB/oct dipole equalization
  9 -  12 dB/oct highpass equalization 
  ("Linkwitz Transform", Biquad)
 10 -  Variable gain
 11 -  Line driver
 12 -  Power supply
 13 -  Printed circuit boards 
 14 -
  Literature
- Woofer EQ & LR2 lowpass filter - w-xo-lp2.gif
-
Active L-R crossover - xo12-24.gif
- s-plane for highpass filter - 12db-hpf.gif
- General allpass configuration - ph-dst6.gif
-
Delay correcting filter - allpass.gif
-
Delay correcting filter - allpass2.gif
- Shelving high-pass - shlv-hpf.gif
- Shelving low-pass - shlv-lpf.gif
- Bridged-T low-pass - shlv-lp2.gif
- Active inductor 1 - inductr1.gif
- Active inductor 2 - inductr2.gif
- Room EQ - phn-room2.xls  
-
Pole-zero transform circuit - f0Q0fpQp.gif
-
Closed box response vs. impedance - f0Q0.gif
- Pole-zero equalization - pz-eql.xls
- Linear dB gain control - gain-adj.gif 
- Attenuator with Rout spec - attnrout.gif
- Input impedance measurement - input-r.gif
- Loudspeaker System Design
- Q0 < 0.5 equalization - sb186-48.gif
- Q0 and ferro-fluids - sb186-50.gif  
- Attenuator with Rout spec - attnrout.gif
- Add-on woofer - xo-pcb.gif
- Active 4-way crossover/EQ -  4w_block.gif
- Surround - Surround loudspeaker construction  
- FAQ - Frequently asked questions - Power response - pwr-resp.gif
- Wedge micrometer - wedge-micro.gif
- Corner dipole woofer - corner-dp.gif
- Dipole placement - rfl1-dpl.gif
- Cardioid placement - rfl1-crd.gif
- Beethoven Elite
- Diffraction from baffle edges - Diffraction 
- Power to drive a dipole woofer - dipole_spl_limit.htm
- Dipole SPL limit
- Monopole SPL limit
Three-Box Active
System (1978)
- Loudspeaker System Design - Part 1
- Part 2
- Part 3
- Excursion-Limited SPL Nomographs
- Speaker Builder Mailbox
Reference earphones - Reference earphones
- ER-4S equalization
  Headphone amplifier
  Equalizer circuit
- Sony Fontopia earphones
- Shure E2c earphones
- Improved Headphone Listening - X-feed
Surround Sound 1 - Ambience recovery from a 2-channel CD
2 - Refinement of ambience recovery
3 - SACD and DVD-A use of the center channel
4 - A few SACD and their need for a center speaker
- Surround - Surround loudspeaker construction

 

Products ...

ORION - PLUTO
by Wood Artistry
 
Do-It-Yourself - Do-It-Yourself products

 

Resources ...

Publications

- Letter to The Audio Critic - tac29.gif
- Letter to AES Journal - Woofer accuracy.rtf
- Which loudspeaker parameters? - AES'02.htm
- Multi-burst signal - mlt-bst0.gif
-  Multi-burst sound - 100mbst4.wav
-  Multi-burst test - mlt-bst1.gif    
-  Compact dipole speaker - cmp-dipl.gif
-  Acoustic power response - pwr-resp.gif
-  Beam-width of dipole array - beam-dpl.gif
-  Excursion limited SPL - theory.gif
-  Excursion limited SPL - spl_max1.xls 
-  Loudspeaker system design - sb80-3wy.htm ,
   sb80-3wy.zip
-  Closed box response vs. impedance - f0Q0.gif 
-  Pole-zero transform circuit - f0Q0fpQp.gif
-  Component values for p-z transform - pz-eql.xls
-  Real poles p-z transform - sb186-48.gif , sb186-50.gif
-  Shaped tone-burst - 20brst1.gif
-  Shaped tone-burst sound - 1kblkman4.wav
-  Shaped tone-burst generator - brst_gen.gif

-  Peak detecting mic. preamp. - mic_pk.gif
-  Passive L-R crossover - passv-xo.gif
-  Active L-R crossover - xo12-24.gif
-  L-R crossover response -  xo12-24b.gif
-  Delay correcting filter - allpass.gif
-  Audibility of delay distortion - phs-dst2.htm
-  Headphone cross-feed-1 - hdphon1.gif
-  Headphone cross-feed-2 - hdphon2.gif 
-  High-resolution audio, 2000 - Presentation
-  Loudspeaker talk  - AES'89.htm  
Website CD-ROM
.... and more
Sound Recordings - Sound Demonstration CD
- Toneburst Test signal CD
- Music and Sounds
Links - Links
Other designs - Controlled directivity loudspeaker designs
My current setup - My current audio and video setup
About me - A little bit about work, fun and life
- AudioXpress interview - AXinterview.htm
Site map - When searching for specifics
Home - The place to start exploring
- What's new

 

Conclusions ...

 

Site map

Concepts ... Projects ...   Products ... Resources ... Conclusions ...
 

Install the Excel Viewer on your computer, if you do not have access to the Microsoft Excel spreadsheet program. 

 

 

 

What you hear is not the air pressure variation in itself 
but what has drawn your attention
in the streams of superimposed air pressure variations 
at your eardrums

An acoustic event has dimensions of Time, Tone, Loudness and Space
Have they been recorded and rendered sensibly?

___________________________________________________________
Last revised: 02/15/2023   -  © 1999-2019 LINKWITZ LAB, All Rights Reserved