The 1602 was a mid range deck for B&O. Compared to today, you will find the deck to be made from better materials and be considerably slimmer than what is mostly on offer.
It lacks in a couple of ways:
The bass is not as extended or controlled as better decks available and the top end is sweet but a bit less detailed. It is a very comfortable sound to actually listen to and is the B&O trademark. The 20EN is at the top end of B&O cartridges and if it has a decent stylus, I would stay with what you have. Pre-amps are obviously available and get a reasonable one without going crazy! Gram Slee make very good ones but go for the bottom of the range!
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