EP 1308925 A1 20030507 - Sub-harmonic generator and stereo expansion processor
Title (en)
Sub-harmonic generator and stereo expansion processor
Title (de)
Subharmonischer Erzeuger und Prozessor zur stereophonischen Erweiterung
Title (fr)
Générateur subharmonique et processeur pour augmentation d'effet stéréophonique
Publication
Application
Priority
EP 01309021 A 20011024
Abstract (en)
A sub-harmonic generator includes: an input filter (102) operable to receive an input signal containing frequencies from among a first range and to produce a first intermediate signal containing frequencies from among a second range; a signal divider circuit (105) operable to receive the first intermediate signal and to produce a square wave signal containing square wave signal components at fundamental frequencies from among a third range, the third range of frequencies being about one octave below the second range of frequencies; a wave-shaping circuit (114) operable to receive the square wave signal and to produce a second intermediate signal containing sinusoidal signal components from among frequencies corresponding to the respective fundamental frequencies of the square wave signal components; an RMS detector (124) operable to produce an RMS signal corresponding to an instantaneous amplitude of the first intermediate signal; and a voltage controlled amplifier (118) operable to amplify the second intermediate signal by an amount proportional to the RMS signal to produce a sub-harmonic signal. <IMAGE>
IPC 1-7
IPC 8 full level
CPC (source: EP)
Citation (search report)
- [A] US 5473108 A 19951205 - MATSUDA EIJI [JP], et al
- [A] US 4841572 A 19890620 - KLAYMAN ARNOLD I [US]
- [A] US 5369224 A 19941129 - MIYATA TOMOMI [JP]
- [A] US 4866774 A 19890912 - KLAYMAN ARNOLD I [US]
Designated contracting state (EPC)
DE FR GB IT
DOCDB simple family (publication)
DOCDB simple family (application)
EP 01309021 A 20011024