I hope this hasn't been covered, because the search function is "temporarily unavailable", but... How shall I calibrate my 7-ch set up once I have it? I'll be using my 4800 as a pre/pro, and I own VE, but I don't think it is set up for DD EX. Should I just use the receivers test tones for the back channel? Maybe I answered my own question while thinking out loud (I have one of them clicky IBM keyboards), but if there's a better idea, let's hear it! Thanks.