Ok, this is the note I have come up with. Any suggestions?
Dear Neighbor in Apt #456;
Though we have never met before, I have been witness (audible) to your musical selections and on numerous occasions to your very loud movie selections. It is also true that on the rare quiet moments late at night and early in the morning I have even faintly heard your snoring. However, recently the noise level emanating from the bedroom area of your apartment has become, shall we say, more boisterous. To put it bluntly, your girlfriend’s coital screaming has reached a climax (pun absolutely intended). Monday morning’s 5:30 AM wake-up call is what has prompted this note. Although this last weekend’s numerous sessions could also figure in as well. The bed banging up against the wall promptly brought me out of a sound sleep along with the screaming.
My only request with this note is to ask you kindly to consider others in your sexual escapades, not that you should invite others, that of course is completely up to your and your partner. Please be aware that your neighbors around you can hear what’s going on in your apartment and more to the point of this letter, your bedroom when it reaches a certain volume.
We respect your privacy and hopefully you respect ours, but when it interferes in such an audible manner I feel it is time to say something.