J37/C37 alignment and SM900 tape - Gearspace.com
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J37/C37 alignment and SM900 tape
Old 29th January 2013
Gear Nut
🎧 10 years
J37/C37 alignment and SM900 tape


Should anybody have some experience with J/C37 alignment and SM900 tape?

Here's the issue : doing proper PB alignment with accurate test tape on my J37, I can't get high freqs right values in Rec setup then. I mean, even with Rec HiFreqs pots fully counterclockwise, gain is still +2 or +3dB higher than expected. The only way is to compensate by having a -2/3dB on PB alignment.

I'm using SM900, fluxivity 500nWb/m

Should the high operating level be the cause? Or the tape? I don't exactly remember but I think I already did an alignment @355nWb/m fluxivity and I got the same problem.

Old 29th January 2013
Lives for gear
🎧 15 years

That´s interesting....

My guess is it´s the flux...

I do 320Nw/m on my C37, no problem...
I haven´t tried any higher...
I use RMG 900/911 or ATR tape, depending on the band/budget...

180-250Nw/m might have been the oldish standard?

Best of luck!

Old 29th January 2013 | Show parent
Gear Nut
🎧 10 years
I got some infos about. It matches with what I had in mind. Modern tapes have way better performances in high freqs. That should be the reason, less loss in high frequencies. The only way should be some little mod in electronics to allow more decreasing in rec highs.

The way I manage with is a compensation on PB highs alignment as I don't have to care about any external tape playing.
Old 29th January 2013
Lives for gear
Plush's Avatar
5 Reviews written
🎧 15 years
RMGI SM 911 should run well on thst machine. Also a great tape!

Atelier HudSonic, Chicago
Old 30th January 2013 | Show parent
Gear Nut
🎧 10 years
I'll switch to SM911 for my old Studer B30 (same problem) which is older and doesn't allow high operating level. Maybe I'll try on the Jay one day if I have courage enough to make a full new alignment :-)) What's great with the SM900 is the high fluxivity and very low noise.
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