While I'm waiting for my vintage receivers to arrive(eBay purchase) via Pony Express I was trying to understand what the difference was between these two units. I did a search here and didn't come up with much. I did hear mention that the 1515 was a cheaper version of the 2215. Is that true? I thought the 2215 was just an updated version of the model 1515. So many numbers, so confusing! I still need one more receiver for my bedroom (18'x24') and thought something like 1515 with a set of Dynaco A25's or KLH 17's would be just the ticket. I also have a great pair of Pioneer CS-66's that could pull duty in the bedroom. JohnW