I own both the 71 and 77; have heard the 67 and 78 at length.
In stock form, the 71 is simply the best tuner Mac made. The 78 is more sensitive but the 71 is more pure, natural, and sweet sounding. I have no experience with modded Macs.
The 67/77 can be found at lower prices than 71/78 and IMO are the best values.
My 71, built in 1963, has the original tubes. All test strong on my Hickok so don't worry about tube life. I did replace the stereo indicator bulb which is readily available from Audio Classics (great folks by the way) for a couple bucks.
In stock form, the 71 is simply the best tuner Mac made. The 78 is more sensitive but the 71 is more pure, natural, and sweet sounding. I have no experience with modded Macs.
The 67/77 can be found at lower prices than 71/78 and IMO are the best values.
My 71, built in 1963, has the original tubes. All test strong on my Hickok so don't worry about tube life. I did replace the stereo indicator bulb which is readily available from Audio Classics (great folks by the way) for a couple bucks.