Cinemag
(USA)
Sowter
(England)
SJS (England)
Lundahl (Sweden)
Bartolucci (Italy)
Black Art Audio
(Australia)
Hammond (Canada)
Plitron (Canada)
Peerless/Magnequest (USA)
One Electron (USA)
Electra-Print Audio
(USA)
Opt Industries (USA)
Jensen (USA)
Audio Tranformers
(USA)
Partridge - Transformers
& Rectifiers Ltd (England)
Tamura (Japan)
S.E.R.D.I.
Magnetic SA (France)