Older 2 channel DR, any sound diff in series vs par. loop?

[JeffT]

Wondering if there is a tonal difference between the earlier series loop and later parallel loop in the early DR. If so, is this only when the loop is active? I have an older one that was converted at Mesa from series to parallel and was curious.
thanks!

 

[Elpelotero]

I don't think there's a tonal difference in terms of "it sounds tighter and smoother now" or anything like that.

However, you simply get the advantages that one provides over the other.