456 or GP-9? For 1/4" 1/2track mixdown / mastering?

Dr ZEE

Anti-Pro Circles Insider
Without going into 'deep tech' and chemystry ;) ... for mix-down to stereo onto 1/4" tascam 32 15ips. Which tape is better quantegy 456 or GP-9? Well, I know some general deal about what these tapes are. I happened to stock some 7" GP-9s ...and getting pretty good result. But it looks like 456 is couple bucks cheaper and I've seen 10" reels available. so I was thinking ...maybe 456 is the way to go... the same (similar) as GP-9 ...or maybe even better with tascam-32.? Or maybe GP-9 isn't good for tascam 32... or no big difference? ...heh heh
any tip or experience sharing will be appreciated ...
thanx
/respects
 
The 32 is factory set to run on 456 and can be set up, via calibration to run on 499 or GP9 but you will need a calibration tape as well as other test gear to perform the conversion to these hotter tapes.

It's not as simple as just buying the hotter tape formulation and pressing record. ;)

Even still, with 456 and decently hot recording levels, you can expect a signal to noise ratio of at least 70db without noise reduction and for most pop music recordings, that will be more then clean and quiet enough to not hear any tape hiss. You can work with peaks that are near burying the needles and not hear much or any audible distortion either so, perhaps, unless your very finicky, just stick with 456 and enjoy the ride.

Cheers! :)
 
The Ghost of FM said:
You can work with peaks that are near burying the needles and not hear much or any audible distortion ... :)
hah ... that's about how i was dion' it :D
I guess I gotta get couple of 456s and play with it, compare etc... see how it goes judging by ear - that's my cave-way of doing most things anyways :p The perspective of messing with calibration with my deficit of knowledge and experience with these machines isn't very sun-shiny to me :rolleyes:
thank you very mach for info. appreciated.
/respects
 
Dr ZEE said:
Without going into 'deep tech' and chemystry ;) ... for mix-down to stereo onto 1/4" tascam 32 15ips. Which tape is better quantegy 456 or GP-9? Well, I know some general deal about what these tapes are. I happened to stock some 7" GP-9s ...and getting pretty good result. But it looks like 456 is couple bucks cheaper and I've seen 10" reels available. so I was thinking ...maybe 456 is the way to go... the same (similar) as GP-9 ...or maybe even better with tascam-32.? Or maybe GP-9 isn't good for tascam 32... or no big difference? ...heh heh
any tip or experience sharing will be appreciated ...
thanx
/respects

GP9 is better tape. Which is better for *you*?

If you are a tape deck guru and can tweak the machine for bias/tape tension, then GP9 is better for you. If you can't do this then stick with 456.

More machines are wrecked everyday because GP9 is used with the wrong calibration.
 
acorec said:
GP9 is better tape. Which is better for *you*?

If you are a tape deck guru and can tweak the machine for bias/tape tension, then GP9 is better for you. If you can't do this then stick with 456.

More machines are wrecked everyday because GP9 is used with the wrong calibration.
grrrrrrr... :( ..that's sounds like I've stockpiled wrong tape for being lazy'a%s
so, I guess I have to 'go back to school' again ... just what I "need" at the moment :eek:

any tips on where to (or what to read etc) to learn how to 'do it yourself' re-calibrating the machine for hi-out-tapes?

thanks,
/respects
 
Dr ZEE said:
grrrrrrr... :( ..that's sounds like I've stockpiled wrong tape for being lazy'a%s
so, I guess I have to 'go back to school' again ... just what I "need" at the moment :eek:

any tips on where to (or what to read etc) to learn how to 'do it yourself' re-calibrating the machine for hi-out-tapes?

thanks,
/respects

The maintanance manual is what you need to get started. You will need some tools like a spring scale, o-scope, test tape, tweaker, freq generator, voltmeter and some other things I will remember later. You may want to use the 456 and be happy that you never touched the machine though. Once you start "calibrating" you can't go back without professional help (or if you actually get it right, you are all set). If the machine is a three head, it is far easier to bias than a two head machine. The home type machines are far more complicated than pro machines as they were never designed for daily calibration.
 
The operations/maintenance manual for the '32 goes into great detail as to how the electronics are calibrated and what you need to have to do it.

It explains how to check the tension, but I don't think it tells how it adjust it.

If your machine came without the manual, I believe you can buy them. Alternatively a model 34 or 38 manual should work (since lots of the '32 manual refers to more than two tracks..)
 
thank you, guys for input here. It sounds like the best is actually to get another one , professionally set-it up for gp-9 ..... instead of messing with one deck plus I'd need to buy a buncha' tools. I see calib.tape is about 90 bucks..hah, I bought the machine for $102 (was lucky, thou ... it was as-is without even test-play/reck, just power-up and lights on :) )
oh well, I'll see what I do next. gotta shop around. maybe just get some 456s for now...the easiest way.

/respects
 
on second thought, being a non-so-scientifically-correct 'electronics freak' I may get into this myself :D , and also, well, the tools can be useful for other 'projects'... so ..hmmmmmmm

acorec said:
You will need some tools like a spring scale, o-scope, test tape, tweaker, freq generator, voltmeter and some other things

What is 'tweaker' ? :o

Would be any advice on what the cheapest and , well sort of good enough to do this sort of work, model of freq.generator and where to look for one? Are these things 'e-bayable' :)? , meaning anything I should be trying to spot on e-bay?
Any advice on o-scope?
I have one general use v/ohm meter/tester.

Guys, where do you shop for tools, testing equipment etc...?

thanks a ton for all the info :)
/respects
 
Dr ZEE said:
on second thought, being a non-so-scientifically-correct 'electronics freak' I may get into this myself :D , and also, well, the tools can be useful for other 'projects'... so ..hmmmmmmm



What is 'tweaker' ? :o

Would be any advice on what the cheapest and , well sort of good enough to do this sort of work, model of freq.generator and where to look for one? Are these things 'e-bayable' :)? , meaning anything I should be trying to spot on e-bay?
Any advice on o-scope?
I have one general use v/ohm meter/tester.

Guys, where do you shop for tools, testing equipment etc...?

thanks a ton for all the info :)
/respects

a "tweaker" is a small special screwdriver with a hood so that you can adjust those #%&*(-king trimpots that are everywhere on every channel of the tape deck. The tweaker prevents the screwdriver from popping out of the pot screw every 1/90000 of a turn.......or so.

Get it at any electronics store.
 
acorec said:
The tweaker prevents the screwdriver from popping out of the pot screw every 1/90000 of a turn.......or so.

Get it at any electronics store.

ahhhh! I see! Like this? :D
found one on amazon :p

seriousely, thank you for info again,
/respects
 
About half of what acorec posted is wrong. Tape tension has nothing to do with changing from 456 to GP9. Sure, if you want fully to calibrate a machine, you should check the tape tension and adjust it to bring it into spec. But that's true whatever tape you use. It isn't like you use a different tension for GP9 or anything.

Nor do you need an oscilloscope. They primary purpose is to check head alignment. Which you should do, yes, but changing from 456 to GP9 doesn't have anything to do with it.
 
sjjohnston said:
About half of what acorec posted is wrong. Tape tension has nothing to do with changing from 456 to GP9. Sure, if you want fully to calibrate a machine, you should check the tape tension and adjust it to bring it into spec. But that's true whatever tape you use. It isn't like you use a different tension for GP9 or anything.

Nor do you need an oscilloscope. They primary purpose is to check head alignment. Which you should do, yes, but changing from 456 to GP9 doesn't have anything to do with it.


GP9 is a thicker tape. If you don't set tape tension - or- you can't set tape tension (machine has no cal routine), don't use it. My MCI JH24 2" machine is settable both electronically and mechanically for any tension. The GP9 will have a much higher tension right off the bat and if not corrected, your heads will wear amazingly fast.

You don't need a scope, you can use VU meters (must be analog voltage reading meters) to set azimuth.

Like I said before, not too many techs know about the proper way to set up a machine for these high bias tapes. That is why GP9 and 3M 996 have gotten the reputation for eating heads.
 
acorec said:
GP9 is a thicker tape. If you don't set tape tension - or- you can't set tape tension (machine has no cal routine), don't use it.

Overall thickness of GP9 = 2.13 mils, of 456 = 2.02 mils. They both come on the same reels (except, of course, that the GP9 reels are red). It's not enough to make a difference.
 
sjjohnston said:
Overall thickness of GP9 = 2.13 mils, of 456 = 2.02 mils. They both come on the same reels (except, of course, that the GP9 reels are red). It's not enough to make a difference.




From the best analog multitrack tec out there (Eddie Ciletti):
"...Note: Modern high-output tapes are not a good match for older pro or narrow-format semi-pro machines, which may not have enough current to fully erase previously recorded material. Compared to older generations of tape, modern tapes can be an additional half-mil thicker than the original "1.5 mils," for which the machines were designed. (one mil is 0.001 inches or 25.4 microns.) Thicker tape is harder to pull and, if tension is not adjusted for these tapes, can cause more than the usual amount of headwear. Attempting to operate any narrow format machine without its integrated NR is not recommended, nor should the operating level be changed from the manufacturer's recommendation. While it may be possible to disable NR for selected tracks, there will never be enough headroom to sufficiently lower the noise floor for all tracks....."


So, you can argue with me, and Eddie, and a dozens of other pro techs (and we all have done this stuff for years and years) or you can wear your heads down to nothing. It really is your call. I have seen what an improperly set up machine can do to heads with 3m 996 (which is what I use). The last time I had my heads re-lapped. they had a remaining life of %70. My MCI 2" is a machine from 1983. It is used quite alot. I set tape tension with every new reel along with alignment before every session.


And:
"....Professional machines have a generously wide adjustment range, and many narrow-format machines have extremely limited range. Many Tascam MS-16s do not have enough range in the bias control to accurately find the peak at 10 kHz. Most Fostex machines have a continuously variable bias capacitor. Without a voltmeter or oscilloscope, it is possible to be on the wrong side of the bias peak...."

Home machines are much tougher to align than pro machines. You really need an O-scope if you want to make the job easier (or sometimes possible). Two head machines are the hardest to align.
 
yo I dont want to argue or anything. but during the shortage, GP9 was all I could get. I ran it on my E-16 without NR. very clean sounding. It wasn't zero hiss, but it was tolerable. I didn't re-calibrate anything. I only recorded one song though.
 
acorec said:
From the best analog multitrack tec out there (Eddie Ciletti):
"...Note: Modern high-output tapes are not a good match for older pro or narrow-format semi-pro machines, which may not have enough current to fully erase previously recorded material. Compared to older generations of tape, modern tapes can be an additional half-mil thicker than the original "1.5 mils,"

He's not talking about the difference between 456 and GP9. This should be obvious, as 456 is not 1.5 mils thick, but -- wonder of wonders -- about "half a mil thicker." The "modern high-output tape" he's talking about is 456.

The rest of what he says has to do with the electronics, not tape tension. Whether your deck will bias up for GP9, or has enough headroom to even use the extra headroom on the tape without the electronics distorting, is a whole different question. A great many machines that were built for 456 can.

That is an open question. As I said, not everything you originally posted is wrong ... it was about half right.

"....Professional machines have a generously wide adjustment range, and many narrow-format machines have extremely limited range. Many Tascam MS-16s do not have enough range in the bias control to accurately find the peak at 10 kHz. Most Fostex machines have a continuously variable bias capacitor. Without a voltmeter or oscilloscope, it is possible to be on the wrong side of the bias peak...."

More stuff about electronics. The fact a machine might not bias up for GP9 is a good point. Of course, you didn't even mention it in your original post.

Home machines are much tougher to align than pro machines. You really need an O-scope if you want to make the job easier (or sometimes possible).

Nonsense.

You need an oscilloscope if you want to adjust azimuth quickly and accurately. That's the case if you're using 456, or GP9, or 406, or hand-cut strips of paper rubbed with iron oxide. That's the case if you never change the tape you use. It's got nothing to do with the choice between 456 and GP9.

You can adjust bias without an oscilloscope. If you use an oscilloscope to adjust bias, all you're doing is using the oscilloscope as a voltmeter. You can use a voltmeter to do the same thing. You can use the machine's own VU meters. I'll take Mr. Ciletti's word that "it is possible" to be on the wrong side of the voltage peak when adjusting bias on "most Fostex machines." This, of course, is irrelevant to those (like the guy who asked the question in the first place) who don't have one of those Fostex machines, doesn't say either a voltmeter or an oscilloscope is necessary, and doesn't say an oscilloscope is necessary at all. Indeed, while it is slightly different from what Ciletti says, it seems that with a continuously-turning bias pot, it's possible to be on the wrong side of the peak if you do use a voltmeter.

If you quote something, then misstate what it says, you're just confusing people.

Two head machines are the hardest to align.

That, on the other hand, is true enough. Of course, a Tascam 32 is not a two-head machine ....
 
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Yep, Eddie is the man. I agree with acorec here for the most part. It's not that you can't throw an odd tape on occasionally. You can get away with it once or twice with no apparent ill effect. It’s that you don’t want to make a habit of it.

For one thing the bias will be off, so even if it “sounds ok” it’s not optimal. Your highs will be squashed with too much bias and signals distorted with too little bias You won’t be getting all you can out of the tape.

Acorec has detailed the other problems here and in earlier threads, so I won’t carry on.

So FALKEN is right in that you can throw GP9 on in a pinch and get something on tape.

acorec is adhering to best practices though by pointing out the devil in the details.

Sjjohnston, I too thought Eddie was talking about stuff like GP9 and SM900 as the hot tapes in that article. I’ve read it in full some time back and that was my impression. I will look at it again – I may have missed something. But you are correct, at one time 456 and 226 were the hot tapes and some older machines couldn’t push them hard enough.

-Tim
 
sjjohnston said:
He's not talking about the difference between 456 and GP9. This should be obvious, as 456 is not 1.5 mils thick, but -- wonder of wonders -- about "half a mil thicker." The "modern high-output tape" he's talking about is 456.

The rest of what he says has to do with the electronics, not tape tension. Whether your deck will bias up for GP9, or has enough headroom to even use the extra headroom on the tape without the electronics distorting, is a whole different question. A great many machines that were built for 456 can.

That is an open question. As I said, not everything you originally posted is wrong ... it was about half right.



More stuff about electronics. The fact a machine might not bias up for GP9 is a good point. Of course, you didn't even mention it in your original post.



Nonsense.

You need an oscilloscope if you want to adjust azimuth quickly and accurately. That's the case if you're using 456, or GP9, or 406, or hand-cut strips of paper rubbed with iron oxide. That's the case if you never change the tape you use. It's got nothing to do with the choice between 456 and GP9.

You can adjust bias without an oscilloscope. If you use an oscilloscope to adjust bias, all you're doing is using the oscilloscope as a voltmeter. You can use a voltmeter to do the same thing. You can use the machine's own VU meters. I'll take Mr. Ciletti's word that "it is possible" to be on the wrong side of the voltage peak when adjusting bias on "most Fostex machines." This, of course, is irrelevant to those who don't have one of those Fostex machines, doesn't say either a voltmeter or an oscilloscope is necessary, and doesn't say an oscilloscope is necessary at all. Indeed, while it is slightly different from what Ciletti says, it seems that with a continuously-turning bias pot, it's possible to be on the wrong side of the peak if you do use a voltmeter.

If you quote something, then misstate what it says, you're just confusing people.



That, on the other hand, is true enough.

Well, I will continue to set tension on my deck with the changing or reels like every other pro analog studio and let the home guys do whatever they want. It is not my business.


A short passage from Mr. Cilleti:

"....Stick with standard formulations (Ampex 456, 3M 226 or AGFA/BASF 911??). These tapes are 1 1/2 mils thick and have 1 mil cousins 457, 227 and ??? High-output tapes such as Ampex 499, 3M 996 and AGFA/BASF ??? are physically more difficult to pull through the mechanism. The resulting tension increase tension will accelerate head wear......"


From MIX Mag about tape:
".....Why can't I just record louder on the tape I have rather than go with GP9 or 456? Tape that's designed to work at a +9 or a +6 have thicker coatings of oxide on them. The thicker the coating, the higher the sound level will be before the tape "saturates" or distorts. In fact you will notice that GP9 is stiffer than 456 even though they're both "1.5 mil" tapes.

Can I use GP9 for the increase in transparency yet not adjust my deck to a +9 operating level? Sure. But you won't get the large decrease in background noise that you could have if you did.


I learned about setting the tension for each type of tape from an engineer at Synchro-Sound (In Boston before the "Cars" bought it). I always set tension and find that the deck aligns easier when the tension is set for each formulation.

The thing is that if I adjust the tension for 456 on my MCI, then immedietly put on the 996, the tension measures way too high. I then adjust the tension so that it is in spec. If I put on a reel of 456 immedietly, then the tension measured is too low. I adjust to proper tensin.


When the machine is adjusted for each formulation, the tension is the same, but you have to set the tension when using the heavier 3m996/GP9 formulations because they are stiffer, thicker and the reels weigh more than the 456 and variants.
 
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