I'm not going to try to recalibrate my deck for +10.5db (or even +9db for that matter) so I can use ATR.
Well, you don't really have to. You can use any level you want. The ATR tape, however, requires more bias but I suspect it will be good to use 'as is' and biasing our decks to it [to get more accurate performance] should prove not a problem. As an example, lets take Quantegy 456 / RMGI SM911 / RMGI SM468:
456
Coercivity 320 Oe
Retentivity 1500 Gauss
SM911
Coercivity 320 Oe
Retentivity 1450 Gauss
SM468
Coercivity 380 Oe
Retentivity 1400 Gauss
Now, lets take the ATR tape:
ATR
Coercivity 365 Oe
Retentivity 1590 gauss
As you can see, bias (as per the coercivity) requirements, for the ATR tape, fall somewhere between the 'standard' (456 / SM911) and SM468, which requires most bias.
The only thing which may be problematic is that the ATR tape is a bit more thick (2.28mil ATR vs 1.97mil SM911 vs 1.89mil SM468). Obviously the extra ATR operating level (which we'll never use, at least on this board) is responsible, at least in part, for the greater thickness of the ATR tape, which possibly makes it more stiff and thus may not be good for the tape transport and heads, even if it can bias up to it. The mechanical specs of this tape may be too much, at least in the long haul, for a 'semi-pro' recorder to handle. I mean, the ATR tape may even be spec'd higher than the GP9, which one should never use on this type of gear, not that it's a bad tape, but that the tape is just too hard on the tape transport, which includes the motors, tape path and heads, not to mention being worried about possible incomplete erasure and less than ideal head-wrap for best freq response (on these 'home studio' decks).
I, however, am still wondering if the extra .31mils would be problematic, at least transport stress wise.
As far as price, the ATR tape so far has had great reviews, being the highest spec'd tape so far and the heavy duty precision reels, which undoubtedly increase the price, are well worth it. I think that if one has a machine capable of easily handling this tape, than it's the best tape so far, at least from the specs and reviews so far.
That's my thought as far as the tape is involved but I'd get the empty 6 screw precision reels, in a heart beat. If they're anything like the heavy duty Ampex precision reels then I'm sold.
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