Theoretical idea for you amp gurus - where to sample the feedback
OldmanSRS
Posts: 419
The Adcom GFA-555 collects the feedback signal from the speaker wire connection at the rear of the amp chassis. If the feedback sample point was extended to the speaker wire connection of the SPEAKER, would this provide more accurate feedback taking into account and allowing the amp to correct for the effect of the speaker wire on the signal path?
'65 427 Shelby Cobra
'72 Triumph TR-6
__________________
'88 Polk SDA SRS 1.2, with upgraded XO caps and Erse SDA inductors
'86 Polk SDA CRS+
'84 Polk Monitor 10A (Peerless tweeters)
'05 HSU VTF-3 Sub (Original OEM)
'20 HSU VTF-3 Sub (three more, 100% cloned)
'93 Carver TFM-35
'88 Carver M-1.0t
'88 Adcom GFT-555
'88 Adcom GFP-555
'88 Adcom GFA-555 (upgraded/restored)
'88 Adcom GFA-555 (a second one upgraded/restored)
'05 Onkyo DV-555 media
'89 Fosgate 360 Digital Space Matrix
'89 Fosgate 360 Digital Space Matrix, internal surround amp bridged to drive only a center channel
'91 Kenwood Basic M1D Amp
'89 Pioneer Laser Disc media
'89 Sony SuperBeta HiFi media
One PGA2310 based custom built remote volume control
Four Polk T-15's
Four Polk TSi-200's
Four Polk TSi-100's
Two Polk CS-10's
'72 Triumph TR-6
__________________
'88 Polk SDA SRS 1.2, with upgraded XO caps and Erse SDA inductors
'86 Polk SDA CRS+
'84 Polk Monitor 10A (Peerless tweeters)
'05 HSU VTF-3 Sub (Original OEM)
'20 HSU VTF-3 Sub (three more, 100% cloned)
'93 Carver TFM-35
'88 Carver M-1.0t
'88 Adcom GFT-555
'88 Adcom GFP-555
'88 Adcom GFA-555 (upgraded/restored)
'88 Adcom GFA-555 (a second one upgraded/restored)
'05 Onkyo DV-555 media
'89 Fosgate 360 Digital Space Matrix
'89 Fosgate 360 Digital Space Matrix, internal surround amp bridged to drive only a center channel
'91 Kenwood Basic M1D Amp
'89 Pioneer Laser Disc media
'89 Sony SuperBeta HiFi media
One PGA2310 based custom built remote volume control
Four Polk T-15's
Four Polk TSi-200's
Four Polk TSi-100's
Two Polk CS-10's
Post edited by OldmanSRS on
Comments
-
It can and sometimes is done (more often in power supplies). But it brings with it a can full of engineering issues. Just one design error and you have an oscillator or an interference receiver.
-
There are some merits to including the speaker wire in the feedback loop,such as a net increase in damping factor.Since it would now be determined at the speaker binding posts, the resistance of the speaker cable will no longer affect it.However other than Kenwood with their sigma drive and one or two others the approach does'nt seem to offer important enough benifits outside some marketing.
