Can't tell without taking it apart unfortunately. I think the most important question to answer now is which one sounds better. Pointy or not? I assume that the absolute last revision though is the worst with the non-amorphous head.
So open it up!! We need to know what serial # the Dolby chip changed. Probably the last version of the head is the worst, because that’s when the bean counters stuck their nose in. I believe that Valentin said he couldn’t hear a difference between the first two versions of the heads, though others thought the pointy was better. I believe Valentin’s opinion—- he knows these decks exceptionally well.
Which one sounds better will have some degree of subjectivity, but in my opinion some objective statements can be made: 1. If there is a difference, it should be audible. Listening the same tape with the same headphones, one should be able to tell blindly which is which on a consistent basis with a probability far exceeding 50% (which is a random guess). It can be claimed this depends on headphones used, but a pair of good studio headphones should be able to reveal the difference if there is one. 2. If there is a difference is should be measurable. We should see a difference in frequency response (like better sub-bass or slower high-end rolloff) or THD being lower. Claiming there are differences that can be heard but are not measurable is something that simply does not make sense. The opposite is however true: fact some measurable differences exist doesn't necessarily mean these differences are audible. Yes I did test the pointy vs 35711 side by side in the past (same tape, same headphones) and couldn't identify audible differences. Recently also had the opportunity to test the later 35712 permalloy head, which to me sounds the same as the previous 35711 one. Didn't see significant differences (by significant I mean higher than the normal variation with individual unit) in FR measurements. One would be tempted to assume that the heads got progressively worse with each generation, but there's another thing to consider: this being targeted at the professional market SONY had to keep the sound consistent. Otherwise it just doesn't make sense to manufacture the unit anymore because the (typically business) customers would prefer to buy used ones instead of new. And the target of any company is to sell new products, not to increase the market value of those that are already sold, as in the second scenario they're not the one making the profit.
