Cash for the following makes and brands working or not:

Accuphase
Acoustic Research
Adcom
Akai
AKG
Alpha-Core (Goertz)
Alstine, Audio By
Altec Lansing
Ampex
Amphion loudspeakers
Analog Devices
Analogue Tube Audio
Analysis Plus
Anthem
Anthony Gallo Acoustics
Antique Sound Laboratory
Apogee
Aragon
Arcam
Ariel Acoustics
ATC
Atma-Sphere
Audible Illusions
Audience
Audio Aero
Audio by Van Alstine
Audio Note Japan
Audio Note UK
Audio Physic
Audio Prism
Audio Research
Audioquest
Audio-Technica
Avalon Acoustics
Avantgarde Acoustic
Ayre Acoustics
B&K Components
B&W
Balanced Audio Technology
Bang & Olufsen
Basis Audio
Bel Canto Design
Benchmark Media
Blue Circle
Boesendorfer
Boulder
Bowers & Wilkins
Bryston
Burmester
Cairn
Cambridge Audio
Camelot Technology
Canton
Cardas Audio
Carver
Cary Audio
Cayin
Celestion
Chang Lightspeed
Chord Cable UK
Chord Electronics
Classé Audio
Clearaudio
Coincident Speaker Technology
Conrad-Johnson
Continuum Audio Labs
Creek Audio
Crestron Electronics
Crown
Cyrus
Dali Loudspeakers
dCS
deHavilland
Devore Fidelity
DeZorel
DH Labs
DNM Design
Duntech
Dyna
Dynaco
Dynakit
Dynaudio
Dynavector
E.A.R.
EAD-Enlightened Audio Design
Eastern Electric
ECS
Egglestonworks Loudspeaker
Eico
Electro -Voice
Electrocompaniet
EMM Labs
Energy Speaker Systems
Epos
Equi=Tech
Escalante Designs

Esoteric (TEAC)
Exposure Electronics
Finite Elemente
Fisher
Focal.JMlab
Furman Sound
Furutech
Gallo Acoustics
GamuT Audio
Garrard Turntables
Genelec
Genesis
Goldmund
Goldring
Grado
Graham Engineering
Graham Slee
Grundig
Gryphon Audio Designs
Gutwire
H.H. Scott
Hafler
Halcro
Hansen Audio
Harbeth
Harman Kardon
Heathkit
Hovland Company
Infinity
Jadis Electronics
JBL
Jeff Rowland Design Group
JMlab
Jolida
Joseph Audio
Joule Electra
JPS Labs
KEF
Kenwood
Kharma Loudspeakers
Kimber – Kable
KLH
Klipsch
Klyne Audio Arts
Kondo (Audio Note Japan)
Krell Industries
Kubala-Sosna
Kuzma
Lafayette
Lamm Industries
Lector
Lehmann Audio
Lexicon
Lindemann Audiotechnik
Linn
Living Voice
Loth-X
Lowther
Luxman
Lyngdorf Audio
Lyra
Mactone
Madrigal Audio Labs
Magico
Magnepan
Magnum Dynalab
Manley Labs
Marantz
Mark Levinson
Martin Logan
MBL
McIntosh
Meridian
Meridian
Miller & Kreisel
Mirage Loudspeakers
Mission
MIT Cables
Mobile Fidelity Sound Lab
Monitor Audio
Moscode
MSB Technology
Mundorf
Musical Fidelity
Mythos Audio
NAD
Nagra
Naim Audio
Nakamichi
NBS Audio Cables
Nitty Gritty
Nordost
Now Hear This (NHT)
Nuforce
Ohm Acoustics

Olive
Omega Loudspeakers
Onkyo
Origin Live
Ortofon
Outlaw Audio
Panamax
Paradigm
Parasound
Pass Labs
Pathos Acoustics
Peak Consult
Pioneer
Pilot
Plinius Audio
Polk Audio
ProAc
Proceed
Pro-Ject Audio
Promitheus Audio
PS Audio
PSB Speaker Systems
Purist Audio Design
Quad
Quicksilver Audio
Reference 3A
Rega
REL Acoustics
Revel
Revox
Richard Grays Power Company
Rogue Audio
Roksan
Rotel
Rowland, Jeff
SAE
Sansui
Scott
Sequerra Audio Labs
Shanling
Shindo Laboratory
Shure Corporation
Silverline Audio
Simon Yorke
Slim Devices
Snell Acoustics
Sonos
Sonus Faber
Sony ES
Sophia Electric
Sota Turntables
Spectral Audio
Spectron
Spendor
Stax
Straightwire
Sun Audio
Sunfire Labs
Sutherland Engineering
Synergistic Research
T+A Elektroakustik
TAG McLaren
Tannoy
Tara Labs
TEAC
Technics
The Fisher
Theta Digital
Thiel Audio
Thorens
Threshold
Tivoli Audio
Totem
Transparent Cables
Tri Planar
Triangle Electroacoustique
VAC
Van Den Hul
Vandersteen Audio
Vienna Acoustics
Von Schweikert Audio
VPI Industries
VTL
Wadia
WAVAC Audio Lab
Weiss Engineering
Well Tempered Lab
Western Electric
Wharfedale Loudspeakers
Whest Audio
Wilson Audio
Wilson Benesch
Yamaha
Zanden Audio
Zu Audio