My Grado's were a Christmas present from my wife in 1992 (of course, she bought the HP-1's mostly because they were the top of the line, but read on for the current difference between the HP-1's and the HP'2's). Back then they cost $600 new. They have performed flawlessly for the entire time that I have owned them, except for once, when, after 14 years of perfect performance, one of the driver's stopped working.
My HP-1's were repaired by Joseph Grado himself, even though he was retired, and had moved to South Carolina. He called me directly as soon as he got the HP-1's. This meant that that he had to call me in Hawaii, from where he lived in South Carolina. I was very impressed by this, and by his continuing devotion to his customers. I got the feeling that he could not stand the idea that something with his name on it was not performing perfectly. By that time, the HP-1's were so old that I figured I had long since gotten my money's worth out of them (hmm .. I guess that I should say, "my wife's money's worth").
However, I loved my Grado cans so much that I was thrilled when I heard that Joseph Grado himself was willing to do the necessary repair work. I fully expected the company to say, "sorry, they are too old to repair" when I originally called to see if the HP-1's could be repaired. I had no idea that Joseph Grado would do the repair himself, much less actually call me himself. we need more people like Joseph Grado in American manufacturing (or, maybe I should say, "American craftsmanship").
Of course, when I picked up the phone and heard a voice saying that he was Joseph Grado, I could hardly believe it. He has been one of my heroes ever since my college years 30 years ago when my friend bought a the Grado company after my friend bought one of their cartridges. I thought that it was amazingly cool for my friend to own a cartridge ma de out of wood.
So anyway, suddenly I was talking to Joseph Grado himself, and this is what he said. First, because the drivers are always perfectly matched in his headphones, he would not let the headphones leave his shop with his name on it without replacing both drivers with a pair of perfectly matched new drivers. That was fine with me. The extra cost was well worth it. Secondly, he insisted that I replace what he, apparently, considered the heresy of having bowls instead of flats on a pair of HP-1's. I was embarrassed and mumbled out some lame defense about not being able to find any flats. And finally, he noted that there is no longer any reason for the polarity switches, so he recommended that I have him disconnect them altogether.
So, as to one of the issues in this thread, yes, the review was excellent, and I appreciate being able to read this review. Thanks you to the OP for posting it. However, according to Joseph Grado himself, the designer of the entire HP-1000 Series, all three of these pairs of headphones should be used with flats and NOT bowls (Grado's emphasis, not mine).
Apparently, back when the HP-1's were manufactured, there was a practice within the recording industry which made it helpful to have a polarity switch that could reverse the polarity on one's headphones. When new, the directions simply said to flip the polarity switch back and forth when listening to a song, and to leave the switch in whichever position sounded better on that particular album (polarity normal, or polarity reversed). According to Joseph Grado, the recording industry no longer uses the practice that necessitated the switches, so he recommend that they be disconnected, and thereby allow the signal to take the shortest possible route.
As to polarity switch disconnection that Joseph Grado recommended, please do not ask me to explain, because I did not really understand this myself. But, if Joseph Grado himself recommended disconnecting the polarity switches, who was I to argue? So, when my Grado's came home form Joseph Grado's personal repair shop: (1) they had two new, perfectly matched drivers, and sounded as wonderful as ever; (2) they had flats instead of the bowls that offended Mr. Grado so much; and (3) the polarity switches were disconnected. Now maybe this is only the placebos effect, but with the polarity switches disconnected, they seemed to sound even a bit more wonderful than before. It has been five years since the repair, and my HP-1's have still, after the repair, performed with the same perfection and sonic beauty that the had before the repair.
So, what does all this mean for the difference between the HP-1 and the HP-2. Well, my non-expert opinion is that the only differences that I could make out between the two were the existence of a polarity switch on the HP-1 design (same drivers, etc., I think). Also, if memory serves me correct, the headband on the HP-1 is a bit nicer (the HP-1's have a very nice metallic headband covered with very nice, high-quality leather). So, at this point, would I pay extra for a set of HP-1's if I was in the market to buy a set of series HP-1000 Grado Headphones?
No, I would not. Don't get me wrong, I love my Grado HP-1's, and I would not trade them for a pair of HP-2's. However, if I bought a used pair of HP-1's with the polarity switches still connected, the first thing I would do would be to send them to Joseph Grado to have the polarity switches disconnected. So, my bet is that, if one is looking to buy a pair of Grado Series HP-1000 headphones, and if what one is seeking is sonic beauty (and not collector's value), and if a pair of HP-2's of equal age and quality are available for a lower price than the HP-1's available, then I would go for the HP-2's. You would get equal sonic beauty for less money, and the only cost would be, possibly, the bit of extra comfort that the HP-1's MIGHT provide.
One final note: I am an unabashed Grado fanboy, this is not a review, and I have made no attempt to be unbiased. This is a story, and not a review. The purpose of the story is to report my satisfaction with my Grado HP-1's, and to report that, if I understood correctly what Joseph Grado himself told me, then their is no longer any sonic difference between the HP-1's and the HP'2's because there is no longer any need for the feature that was the main distinguishing factor between the two: the polarity switches.
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