Back in the day when duplicating tapes was a day job for me, they  
said that side 2 of cassettes duped ay high speed both sides at once  
would sound better than the side 1 would. Never made much difference  
on cassettes, especially at 64 or 128IPS dupe speed, but some people  
told me copying 2 tracks worked better in reverse too... They said  
the electronics could respond to transients backwards better than  
forwards. I have no empiric evidence of this though.

Just old tape tales by now, but this had me thinking back... or  

I have transferred some quarter track tapes doing all four tracks at  
once top a four channel A/D, and not noticed a significant  
difference, but it is easier to do them one side at a time as then  
they end up tails out, as long as it is an hourly job and not a mass  
flat fee transfer project.

Hope this isn't irrelevant!

Lou Judson
Intuitive Audio

On Oct 8, 2009, at 1:59 PM, Richard L. Hess wrote:

>> It's not the digital realm, its the way the reel electronics  
>> handle transients and phase
> There appears to be waveform differences between playback in the  
> two directions after accounting for the polarity flip. To my ears,  
> this is an acceptable tradeoff for copying oral history tapes in  
> half the time. This is especially true of mid-to-low-fi recordings  
> such as some 3.75 and most 1.88 in/s reels.
> Cheers,
> Richard