It's basically the old BASF / EMTEC tape, under a different brand, RMGI this time. Yes, it's very good tape.
What exactly is biasing and can one do it on their own or should it be left to a professional?
In a nutshell, it's a super high [inaudible] high frequency, which is added to the signal, going to tape, to reduce distortion and make recordings more faithful to the original source.
Biasing actually is a very simple process, like tuning a radio but you really do need a service manual and also it is a bit more tricky on a 2 head machine, such as your 388.
I personally would get a spool of 7" LPR35 tape and try recording something. If all is good and well, then I wouldn't bother tinkering with bias. I still would urge you to read the manual, especially the sections on mechanical / electrical adjustments and get familiarized, as anyone who owns analogue today should.
You should be more concerned about the condition and cleanliness of the tape path, heads etc... and if the pinch roller and capstan belt are in good good condition.
I personally don't trust any outside person, to dick around with my machines, so I'm not one to recommend going to a tech.
It's best to learn this stuff yourself.
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