Can you clarify what you mean by print-through? Standard print through shouldn't have anything to do with the erase head. It's the tape reporting some magnetism physically transferred from subsequent (or previous) layers that have wrapped adjacent to the area that you're hearing. Since the erase head is positioned prior to the record head as the tape passes along, it doesn't matter if it's calibrated well or not. It's already done its job (or not) by the time the machine imprints the tape with the new signal via the record head.Different story, however, if your tape seems to report ghosts of previous recordings indicating less than full erasure.= Justin

Hello,Wondering if there are any Mm1200 users here.I have been using RMGI SM900 but experiencing print thru. I have heard that the erase current generated by the erase head on these machines were never built to go deep enough to handle this kind of tape. Conventional wisdom says to crank the erase heads more but it may not adjust this far. An alternative is maybe SM 468 or even 911 tape.Thoughts?Best

Both issues seem to be occurring. There is intermittent faint evidence of recordings from sessions way back. Though also when rerecording within a session, sub frequencies from bass drum and elec. bass are present. The erase head is not adjustable any further than the point it is. I am about to try and resolve this but I was seeing if anyone had any insight in regards to using modern tape (like rmgi 900) within MM1200's and if this was a common issue.Thanks for your help

I don't have any direct experience with this, but I know people have used those machines with high output tape (900, 499, gp9, ATR). There is a way. Print through won't change, but it's rarely a noticeable problem, unless you are hammering the tape extremely. You have a manual? I can't remember if the 1200 has a multi-step process like other older machines, which might include adjusting a tuning circuit for the erase frequency, then gain...ATR Service in PA used to deal with those machines (20 years ago). Dan might be able to direct you to some common modifications...I also recommend joining the ampex list, and searching/posting there. Lots of great expert experience to tap into.http://lena.recordist.com/mailman/listinfo/ampexGood luck.

Try the Ampex MM1200 Facebook user group. It s a closed group but there s some knowledgeable folks on there.

Do you have normal bias cards or PURC cards onboard ?