I don't have a definitive answer to your question but I have never noticed that the earliest  electrical 78s sound tubbier or excessively bassier than later ones.  If the bass wasn't reduced during recording, (which is what recording equalization does), then the bass extreme would be 20dB to 25dB stronger than equalized recordings; this would cause visibly huge modulation of the grooves, might even damage the diaphragms of acoustic sound boxes or could miss-track.  My understanding was that the mechanical characteristics of Orthophonic and Viva~Tonal sound boxes compensated to some degree for the recording characteristics of early electrical recordings.

db



On Thursday, December 19, 2013 1:49:19 AM, Steve Smolian <[log in to unmask]> wrote:

Do we know if the early commercial electrics by Victor and HMV used any equalization?  Since there was no commercial record player on the home market that used an amplifier until November, 1925, there’s an April-October or later period where there is no means of introducing a circuit that inverts any electronic change from what reached the cutting head. 
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>The record companies would not abandon the record market which used the acoustic playback process for half a year or create a product that sounded poor on the installed base of home players.  Yes the acoustic Orthophonics were available by then but few could afford them. 
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>If this  is so, such 78s should be played back flat.
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>Any hard data on this question?
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>Steve Smolian
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