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

[Dr ZEE]

ok, here's the question then.

Would it be correct to guess, that, let's say: IF the tension increase 'amount' on 2" tape machine when 'switching from 456 to GP-9' is X, then on 1/4" tape machine it would be 1/8xX (or say the effect would be 85-90% less).
Here's what I am trying to understand here. If the thikness (and I mean thikness as a factor ALONE!) of the tape effects the tension, then WHY? What makes thiker tape to go 'hrder' through the tape path. I can undertand the weight of the reel - that's easy. Are there other factors? I only can guess... maybe the thikness effects the the angle from guide-to-guide in the tape-path, so thiker tape - sharper 'turn' (lower angle) - higher traction - higher tension. From that logic I thought that the effect of tape thikness on tension is much more dramatic on wider tape. So, then, how really it would be noticable as head-wear-factor on 1/4" machine and especially if the deck is being used only in 'personal studio' just for mix-down/matering (ie, it is not a pro-studio everyday use)... see where I'm going with it?

The electronic adjustment is another story thou. It sounds like one can get away without doing it, but, yes at the expanse of not taking 100% out of tape's capability.

thanks again for all the info and input here.

and, guys, c'mon now .... stop 'fighting' and gettin' emotional. You are not the first year in 'tech biz'.... so you must know how it goes. Also, there are tons of 'not-so-scientific' assumptions in the world of pro-recording, often comming from 'big names' ... , ...so ...
well,

take it easy, guys

/respects

 

[acorec]

ok, here's the question then.

Would it be correct to guess, that, let's say: IF the tension increase 'amount' on 2" tape machine when 'switching from 456 to GP-9' is X, then on 1/4" tape machine it would be 1/8xX (or say the effect would be 85-90% less).
Here's what I am trying to understand here. If the thikness (and I mean thikness as a factor ALONE!) of the tape effects the tension, then WHY? What makes thiker tape to go 'hrder' through the tape path. I can undertand the weight of the reel - that's easy. Are there other factors? I only can guess... maybe the thikness effects the the angle from guide-to-guide in the tape-path, so thiker tape - sharper 'turn' (lower angle) - higher traction - higher tension. From that logic I thought that the effect of tape thikness on tension is much more dramatic on wider tape. So, then, how really it would be noticable as head-wear-factor on 1/4" machine and especially if the deck is being used only in 'personal studio' just for mix-down/matering (ie, it is not a pro-studio everyday use)... see where I'm going with it?

The electronic adjustment is another story thou. It sounds like one can get away without doing it, but, yes at the expanse of not taking 100% out of tape's capability.

thanks again for all the info and input here.

and, guys, c'mon now .... stop 'fighting' and gettin' emotional. You are not the first year in 'tech biz'.... so you must know how it goes. Also, there are tons of 'not-so-scientific' assumptions in the world of pro-recording, often comming from 'big names' ... , ...so ...
well,

take it easy, guys

/respects

The tape tension is calculated by (some machines like my MCI) by the capstan and a PLL loop. Measurements are constanly taken reguarding the start/run torque of the tape reel. If the reel weighs more then the start torque is not enough and the run torque is too high. The tension on the running reels becomes too high and the heads wear faster. When the start torque and run torque is set for the weight of the full reel, then the reels start up quicker and settle into the proper run torque.

The effect to the user is that you hit the "play" button, the reel starts to move slowly and gains speed until it hits 15ips (or 30ips). This is the first indicator that reminds me that the tension is set wrong. Not all recorders work like this. You have to know how your recorder works by reading the manuals. Settings like these are always available on pro machines. I don't know about the narrow format machines.Maybe Sjohnson is right and the home machines set tension aoutomatically (?) I can't say. All I can say is that it will hurt your heads if the tension is set too high. How your tension gets set is what I don't know. I only know Studers and MCI 2" decks.

 

[FALKEN]

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 noticed a huge decrease in the amt of background noise. using GP9 without NR was like using 456 with NR. so I did get an increase in transparency. I would be happy to post samples.

 

[Dr ZEE]

I only know Studers and MCI 2" decks.

hah! beautiul! ...

Maybe Sjohnson is right and the home machines set tension aoutomatically (?)

okey. then what's home machine? Is it any machine which happend to end up at 'home'? or is it as opposition to machines which are in big-phat professional studios with persian rugs on the wooden floor, glass coffe tables, theather chears and platinum discs framed all over the walls???? .... Then, what if I drag atr, or mci or a studer (and alike "dish-washer" machine) into my basement studio - will this 'qualify' the machine as 'home machine'?
I've got tascam 32 for mixdown. Many studios used them and still do? Is tascam 32 a 'home machine'? well, it is to me...

so , why the thiker tape "creates" hiegher tension? Is it all about the wight of the reel? Or the thikness of tape itself? If it is all about weight... then you can simply have 'less' tape on the reel (not full reel) ...and then everything will be cool? correct?
You, see, I'm trying to actually understand the 'basic physics' of the 'situation'. And then, so if it is all about how much head-wear the use of GP-9 applies... then how 'bad' the difference is?, does it mean, that if using 1/4" GP-9 on the machine which set for 456 - the head-wear increases up to 50% ?... or is it 25% ...or is it 1%... or is it 0.05% ?.... If it is 1%, then out of 500hour it will shorten the head-life by 5hour.... ok, no big deal - I'll be dead soonner ... now if the deck will be used for mostly mix-down , mastering of personal projects.... then you may never even get over 300hour in your 'production life time' ....

Now, what the hell 'tension arms' for???!!! Arn't they there FOR 'regulating' the tension? ...hmmmmmmmm


/tanks again for info
/respects

 

[acorec]

hah! beautiul! ...



okey. then what's home machine? Is it any machine which happend to end up at 'home'? or is it as opposition to machines which are in big-phat professional studios with persian rugs on the wooden floor, glass coffe tables, theather chears and platinum discs framed all over the walls???? .... Then, what if I drag atr, or mci or a studer (and alike "dish-washer" machine) into my basement studio - will this 'qualify' the machine as 'home machine'?
I've got tascam 32 for mixdown. Many studios used them and still do? Is tascam 32 a 'home machine'? well, it is to me...

so , why the thiker tape "creates" hiegher tension? Is it all about the wight of the reel? Or the thikness of tape itself? If it is all about weight... then you can simply have 'less' tape on the reel (not full reel) ...and then everything will be cool? correct?
You, see, I'm trying to actually understand the 'basic physics' of the 'situation'. And then, so if it is all about how much head-wear the use of GP-9 applies... then how 'bad' the difference is?, does it mean, that if using 1/4" GP-9 on the machine which set for 456 - the head-wear increases up to 50% ?... or is it 25% ...or is it 1%... or is it 0.05% ?.... If it is 1%, then out of 500hour it will shorten the head-life by 5hour.... ok, no big deal - I'll be dead soonner ... now if the deck will be used for mostly mix-down , mastering of personal projects.... then you may never even get over 300hour in your 'production life time' ....

Now, what the hell 'tension arms' for???!!! Arn't they there FOR 'regulating' the tension? ...hmmmmmmmm


/tanks again for info
/respects

"Home Machine" was a phrase coined when analog was the only format sold to the public. It goes back to the mid 70s when all that was available to the public for multitracking machines were pro machines. Tascam was the first to make non-pro machines for 1/10 the cost of pro machines. This was a VERY BIG deal as not too many people had $20,000 to throw into recording.
The "home machines" had big comprimises to the design as the $$ dictated what was and was not necessary to the final product. The biggest area that got ignored was adjustment and alignment ease. If you have no idea, let me tell you that I would rather align any pro machine for free than any home machine for $$$. Now, I love many of the narrow format "home machines" and have had many myself. The top contenders are the Tascam 80-8 and the Fostex E/G-16. These two have been the best ones for ease of aligning/maintanence and longevity in my studio. But, they don't even hold a candle to my MCI 2" or the Studer 2" I had. The pro machines are so easy to work on and designed to be. So:

1. Learn how a tape recorder and the required transport works.
2. Yes, tension arms are for "regulating tension" No, tension arms do not "set" the tension (that is by definition "regulated" after being set to some useful value).
3. Use GP9 with your deck as-is. See how long it takes to grind the heads down.
4. Yes, a Tascam anything is a home machine by design. There were no Tascam pro machines ever made (I am fully aware of those pro-looking machines that were sold and although they were very good machines for the $$$ did not hold up in a pro environment all that well, again, they were made for the pro at a reasonably less $$ figure but were not industry quality machines)

The thicker tape is,....well, thicker but the real problem is that it is "stiffer' and harder to pull through the tape path with 456 tape tension settings. The machine puts too heavy of a torque on the reel and has to be adjusted for the weight of the tape. The tension setting is really done with the reel divided in two. Each reel has equal amounts of tape. The tables are adjusted so that the tension of the running tape is set to the minimum value spec'ed by the manufacturer. If the tension is set wrong, then when yo start the tape:
1. The start torque puts too much of a pull on the tape and stretches the tape every time you hit play or record.
2. The tension is waay too high at the start of the tape and lowers as you get to the middle of the tape, and usually too low at the end of the tape. This non-constant tension wears the heads and guides far faster and also causes wow and flutter to go through the roof.


Really, if you are not prepared to do this type of work, use 456 and leave it alone especially since heads and guides are becomong harder and more expensive to get. I use GP9 on my Fostex E-16 and the tape tension routine is much like my MCI (after reviewing the manual this weekend, I had forgotten about this because I don't use it much anymore). I love the GP9 on the Fostex and think it makes better recordings myself.

 

[Dr ZEE]

2. Yes, tension arms are for "regulating tension" No, tension arms do not "set" the tension (that is by definition "regulated" after being set to some useful value).

But this is what my question is:
If my 1/4" machine's tension is set 'correctly' with 456 (say: 'set level'), then I load GP9.... will the tape tension increase so much that the tension arm will not be able to 'compensate' (or in our case work as mechanical filter - decrease) the tension to the 'set-level'? I am not asking about how it is on freaking 2" studer ... !!!! (it's sure interesting to know , on the side note... thou)

Also, since only Studer and MCI machines are 'real pros' ... does it mean that all of us here simply scewed? Right? This kind of 'attitude' well reminds me similar attitud in digital recording world: "Unless you have/use Protools - you are just a hommy-boy"
****
acorec and all of you guys, who replies! Thank You again a TON for taking time sharing info. I really appreciate it...cos there's no much 'blah' going on the net in the field of analog recording. This place rocks and you, guys, RULE!

/massive respects

 

[acorec]

But this is what my question is:
If my 1/4" machine's tension is set 'correctly' with 456 (say: 'set level'), then I load GP9.... will the tape tension increase so much that the tension arm will not be able to 'compensate' (or in our case work as mechanical filter - decrease) the tension to the 'set-level'? I am not asking about how it is on freaking 2" studer ... !!!! (it's sure interesting to know , on the side note... thou)

Also, since only Studer and MCI machines are 'real pros' ... does it mean that all of us here simply scewed? Right? This kind of 'attitude' well reminds me similar attitud in digital recording world: "Unless you have/use Protools - you are just a hommy-boy"
****
acorec and all of you guys, who replies! Thank You again a TON for taking time sharing info. I really appreciate it...cos there's no much 'blah' going on the net in the field of analog recording. This place rocks and you, guys, RULE!

/massive respects

Somehow, I have to get it so you understand. The "Tension arms" keep the tape tension constant so that the tape travles through the head path with no increase/decrease in tension. The tape tension of the transport is set so that a fixed force pulls the tape towards the heads. The tension arms merely correct any *lack* of tension that the tape has at any given time. An etreme case is when you are FF or REW the machine. See the arms dancing around? (that is why they are called "dancer arms" ). The machine is trying to keep the tension *stable* as the tape unpacks unevenly. The same thing happens when you press play, only you really don't notce it (on a well adjusted transport).

Look at it like this. A gas pump pumps gas at a calibrated pressure (let's say 20lbs). The gas meter figures out what price you pay and takes careful measure of what is going through the nozzle. The meter is like the dancer arms and the pump pressure is like the pump pressure. Now, I can set the pump pressure to any reasonable pressure that I want, and the meter will simply do it's calculations and come up with the answer. The meter does't care what pressure I have, it's only job is to meter the output.

AT 250grms tape tension the dancer arms (tension arms) will keep the tape at 250grms +/- super small amounts

AT 200 grms tape tension, the arms will keep the tension at 200 grms +/- the same.

See?

Now, a tip: Some knowingly unscrupulous individuals who *know* about setting tape tension dupe buyers into believing that worn heads are fine by increasing tape tension to bad levels. Incresing tape tension makes the tape more intimate with the heads and -temorarily- fixes badly worn heads. This is why I take my spring scales with me when I am buying a decks and measure the tension. I wanna know it is within spec before I waste my time checking out anything else. Many pro studio owners did the same thing just to save a few sessions before they bought new heads or had the heads removed for re-lapping.

Now to your specific deck, you have to get a manual and follow the tape tension calibration procedure. I only state that pro machines are designed to be calibrated (Bias, Tape tension, eq etc.) on a daily and sometimes hourly basis for the sole purpose of compatability. Your hme recording machine(s) are not. But, at the same time, home studio machines don't need so much calibration so it is of not much concern for the average guy *except* when using GP9 and 3m 996. These types of tape are unique in that there are only two possible machines designed for the GP9 HO tapes and 1 is currently in production. The Studer.


So, these tapes have been used on all types of machines unless the machine cannot meet the bias requirements and don't have the headroom in the electronics to properly drive the formulation. The fact that GP9 was introduced so late in the analog recorder hardware cycle, the users of this tape have invented the proper way of using it as the company that made it themselves did not have machine manufacturers to help them find the proper settings in product development. Nearly every modern analog machine designed in the late years of analog recording was desined around the Ampex (and Quantegy later on) 456 tape formulation. So,Ampex and Quantagy got a ton of free advice/experience from big time manufacturers. GP9 has been and pretty much continues to be used by pros because they know the clear benefits of it and have the expertise to set up their machines to use it. This info is not easy to find and requires that you learn about your specific machine to set it up right. The sad part is that analog tape recorder service on a pro level is almost non-existant and it is now practically not possible to learn how to do it yourself unless you donate years to the study of electronics and tape transport/electronics. The outcome of most of the do-it- yourself calibrations and bias/strange tape formulations etc. is an unusable machine that you can't just take to the service center and have fixed.


The best thing to do when you are not sure is to go with what the machine was desined for/is working with and call it a day. For me, I am never happy with the norm and always trying to make my analog machine as clean as I can.

I am sorry I ever opened the door on this tape tension thing because I did not realize that the recording world (outside of the pro studios and technicians) had not included it in their alignment procedures. It is a forgotten subject, I guess. But, it is very much included in my MCI and Fostex E-16 manuals and is several steps in the transport alignment section. Not elective, it is required.

 

[acorec]

hah! beautiul! ...



okey. then what's home machine? Is it any machine which happend to end up at 'home'? or is it as opposition to machines which are in big-phat professional studios with persian rugs on the wooden floor, glass coffe tables, theather chears and platinum discs framed all over the walls???? .... Then, what if I drag atr, or mci or a studer (and alike "dish-washer" machine) into my basement studio - will this 'qualify' the machine as 'home machine'?
I've got tascam 32 for mixdown. Many studios used them and still do? Is tascam 32 a 'home machine'? well, it is to me...

so , why the thiker tape "creates" hiegher tension? Is it all about the wight of the reel? Or the thikness of tape itself? If it is all about weight... then you can simply have 'less' tape on the reel (not full reel) ...and then everything will be cool? correct?
You, see, I'm trying to actually understand the 'basic physics' of the 'situation'. And then, so if it is all about how much head-wear the use of GP-9 applies... then how 'bad' the difference is?, does it mean, that if using 1/4" GP-9 on the machine which set for 456 - the head-wear increases up to 50% ?... or is it 25% ...or is it 1%... or is it 0.05% ?.... If it is 1%, then out of 500hour it will shorten the head-life by 5hour.... ok, no big deal - I'll be dead soonner ... now if the deck will be used for mostly mix-down , mastering of personal projects.... then you may never even get over 300hour in your 'production life time' ....

Now, what the hell 'tension arms' for???!!! Arn't they there FOR 'regulating' the tension? ...hmmmmmmmm


/tanks again for info
/respects

I think you really should understand how a tape transport works first. Then you can answer some of your questions. There is no point in wasting time telling you how and why if you are going to come up with the useless points and questions you have come up with. Do some reading and digging and learn about it.