GP9 question

[permanent hearing damage]

OK, i was in a real hurry to get tape and the place i usually order my 456 thru was all out. i've always heard good things about gp9 and never used it before, so i figured "what the hell" and got a reel. my machine is set up for +6. is there anything i should have to worry about if i just hit the tape a bit harder?

[mfdu]

scratch and sniff. i mean, gp9 is the same as 499 (both a higher level tape than 456) so you hitting tape hard on a machine set for 456 should at least give you a feel for the compound.

i don't like gp9 as much as 499 - it flips into distortion rather than sliding gracefully, and i think the tape distortion sounds harsher on gp9 - 499 is smoother (think soft-knee RMS characteristic, as opposed to the hard knee limiting of gp9)

does anyone think thats a fair comment?

if you decide to go with the higher level tapes, you might want to recal you deck, but for the sake of trialling, give it a go and tell us what you think!

chris.

[permanent hearing damage]

so i don't need to worry about adjusting bias or anything for using it this once?

i've used 499 before and never been super stoked, but maybe i'll like this stuff better. not too worried about distortion. noisy band. might be fun. i'll post my thoughts when i'm done.

thanks for your input

[mfdu]

see what you think.

try slinging some tone onto it at difference levels, and see if you like how it reacts.

you know - 1khz at unity, +3, +6, +9 - how does it break up? introduces good or bad overtones? (sorry - retuning drums - i mean harmonics)

using a new tape formulation for the first time in a session is a risky state to be in. you smell what i'm cooking.

pm'd you re. melbourne goodness.

chris.

[msmith4060]

You will need to rebias for GP9. I think its 1.8 db overbias at 10k. +6 is a safe operating level. I personally love GP9. Very clean. Its a formulation you should at least try---very slick.

[mfdu]

but do you think he'll be ble to get an idea of it on a machine biased for 456?

he can at least hear the diff maybe? it certainly is clean, but i don't think it breaks up in such a smooth way . . .

might just be hitting the headroom of the circuitry in the tascam 32, but i don't think so.

chris

[soundguy]

people...

you need to rebias for every single reel of tape you put up on your machine. If you cant handle that, you ABSOLUTELY need to rebias anc cal for every different lot number at least. I put up a post here a few months back while I was in the middle of a melt down with a lot of bad tape I got from quantegy, there's some info on that thread you can apply.

If you think Im full of it on this one you have way too much confidence in both your machine and the consistency of the tape stock. The calibration on a tape deck is held via single turn pots. Most every tape deck I get near gets pretty hot and calibrating my decks, I always wish I had ten turn pots on the EQ controls, that tiny tweak is enough to be moved by temperature shift. So, after a while, your machine physically is going to drift, ie, the pots are gonna move. That is not even touching on the circuit drifting. Then you've got the consistency of the manufacturing process with the tape itself, which is just not very consistent within the context of cal'ing up your machine and then never having to touch it for reels and reels and reels.

All you have to do to prove this to yourself is cal up your deck, then put up a bunch of different reels and look at it and see. If you are spot on reel after reel, be *psyched* because you got lucky. All that applies to the same type of tape...

456 and GP9 DO NOT have the same bias.

Kinda think of bias as the energy it takes to move a big rock. Say you have two big rocks that need to be moved an equal distance, one rock might be more dense than the other or might be sitting on softer ground, so the energy it takes to move to two rocks three feet might be different.

If you want to bias both stocks for say 3dB over at 10K, thats fine, but the amount of bias current needed to get 456 over 3dB may be different than it takes to get GP9 over 3dB.

If you go from one tape stock that has a thin flexable base to a stock with a stiffer base, the head wrap may be different enough to get a different reading at 10K so even if the circuit is theoretically set corrrectly, the different tape may lay against the heads differently enough to require more bias current to get 10k where you want it. Is this going to translate as a 2 dB difference, no, probably not, but it may effect your record eq more than a meter movement (ie, the thickness of the needle) which is generally enough to want to tweak it back into place if you are dealing with a deck that is maintained well enough to provide that kind of accuracy. If you've rebuilt a machine to allow for that kind of expectation it would likely behoove to spot check on that level.

Remember, bias is the optimal setting for the tape, which you chose for your taste. If you throw up a reel without biasing it, even if the bias is way off, the world aint gonna come to an end, but you may have excessive hiss, not enough high end response, not enough depth in the bass and wierd distortion characteristics like suddenly slamming into clipping which may come across as a lack of headroom.

You really do need to set up the machine for each reel if you want optimum performance. Its just like setting the bias in a circuit or setting up your tube amp for a new tube set, its all the same shit. Of course you can just throw new tubes in, and you know, it usually works if you stick with similar tubes but its not optimal, tape machine is the same way. It will work, but you may have to deal with artifacts which can be dialed out through the alignment process, thats the whole point of it.

If you plan on using tape, learn the process and do it every time you turn the deck on. Yes, the learning curve is kinda wierd and it sure is a pain in the ass sometimes but once you see for yourself how different reels from the same lot can be you wont mess with not aligning the machine. Plus, if you have a consistent batch of tape and the machine is in, you just throw the tone up and it will line up. Id say most every reel of old tape wwith mixes from the 70's I have seen has tone before every song, its not a bad habbit to get into, then you KNOW the deck is in, unless you put the tone up you kinda have no idea how far its out and how exactly to compensate for it when you bring the reels to master.

dave

[msmith4060]

Soundguy is correct, but heres the deal--
If its your machine, and youre the only guy using it---youll be fine to keep it periodically aligned. Its not rocket science, and a db down at 10k on a coupla channels is pretty trivial.
That said:
You should rebias for GP9. Its designed to run at a different level period. You could keep it the same, and it will work, but cmon...it takes like 5 mins.

[soundguy]

Soundguy is correct, but heres the deal--
If its your machine, and youre the only guy using it---youll be fine to keep it periodically aligned. Its not rocket science, and a db down at 10k on a coupla channels is pretty trivial.

If you feel that a full dB down at 10K is "trivial" please disregard everything I just posted above, its not for you. If you are a full dB down at 10K, probably best not to think about what is happening between 14K and 19K... Now, depending upon the condition of the heads and electronics you may not be able to get 10K up to zero and thats a bad sign but to label is as trivial, well... Theres nothing wrong with periodic alignment if the machine can hold cal but you are assuming that the tape you are purchasing will all behave the same way...

That said:
You should rebias for GP9. Its designed to run at a different level period. You could keep it the same, and it will work, but cmon...it takes like 5 mins.

level and bias are two different discussions. Level is level. bias will influence the entire EQ curve of the machine.

I suppose you could also start a mix by randomly turing every gain pot on each eq on a console an undetermined amount and then working like that. Somehow I find it a little more efficient to start with the consoles eq's all zero'd. A tape machine requires the same type of "zeroing" for the specific tape that you load onto it.

dave

[permanent hearing damage]

i could be mistaken, but i thought my tech guy told me last time he checked it out that the bias was already pretty much cranked on this thing (a tascam ms-16). if so, what then?

[permanent hearing damage]

and as far as checking all this stuff for each reel of tape, would you just print tones on it and check em out? or is this just a matter of checking the meters?

not to undermine what you're saying, as it sounds perfectly valid, but do most people actually do this for each reel of tape? i don't think i've ever seen it done

[soundguy]

not all electronics can bias everything, if you dont have enough bias current you are out of luck. bummer. Put up a reel of tape, feed it 10k and see where you are at.

It is doubtful that people do this for every reel of tape. It is also much more of an issue for me personally on a reel of tape that I am mixing to as opposed to a reel of tape that Im tracking on. You have the entire mix to make up for shortcomings on the tape deck but your tones have to be perfect on the mix deck if you intend to master it elsewhere and have it translate. My comment eariler about 70's reels was in reference to 2 track mixes.

Put up a reel of tape, cal the machine up nice and tight and print your tones. Go in the next day say if you are mixing and just lay the tones down again. If the tape is the same and the machine is in good shape then this should take like 5 minutes and if you are off, it will just be the tiniest tweak usually to get you back in business, no big deal. If you put up a reel and see massive changes you know you've got to realign things and you'll be totally psyched that you took the 4 minutes to go through the process. I you dont do that, you'll never know exactly what the tape deck is recording. I learned all this crapola the hardway and brought reels to mastering, following the tones on the first reel, the mixes by the fourth reel got progressively wierder sounding and without tone on the tape there was no way to know what had drifted. But you know, I read on the internet that it was ok to not put tones on every reel, so whatever. Really, if you are too lazy to turn the pot or dont know how to turn the pot thats fine but at least print the tones and make a note on the box what they said on your machine. If you have 1K at zero on the left and 1K at -2dB on the right and you dont know to fix that, at least make a note of it on the box so when you go to master it the ME can set up his machine so it was like yours otherwise you are rreally screwed.

The level of detail you put into it is up to you, just be aware that your machine and your tape stock is going to have its own unique reaction regardless of what your tech, me and the entire internet has to say about the issue and its my suggestion that you dont trust any of those sources and simply put the tones up and see whats happening for yourself, then you will know for certain. Its really not a big deal, probably seems like a big deal reading all this but its just one of those things you do, like cleaning the heads every couple hours or splicing leader between takes, seems like a PITA when you first have to start doing it but after a while its just part of the routine that you go through and becomes habit like tuning a guitar or zeroing a console or waiting for a tube amp to warm up, etc. Just part of the process. Be suspect of advice that suggests otherwise. Just because you chose to ignore a step in the process doesnt mean it isnt effecting your mixes.

Just realize that this isnt a big deal, each reel of tape should be tweaked to get maximum performance out of it. If you decide to do it for a while and see no change between reels then maybe you can decide to blow it off or you can think Im ultra tweaker whatever. If you start to see big changes between reels then you'll probably be glad you got into the habbit. I think in todays environment of QC you'd be wise to check each reel, Ive had an interesting winter dealing with these issues to say the least.

In the end you just ultimately have to judge with your ears. Not to totally derail my pitch or anything but if something is drastically wrong you are gonna hear it so dont lose sleep over it. If you dont have enough bias current the tape is gonna sound a certian way and have a usable threshold which you can possibly adjust your recording style around, not a biggie so long as you can get your record EQ to work around bias point, which is the whole name of the game anyway, there are no bias rules that are ethced in stone, it all comes down to what you think sounds good, takes ALOT of experimenting to figure it out, its not as immediately obvious as say, turining the EQ on a guitar mic or something like that, record EQ is pretty subtle within its workable window.

The answer to your question is no, there's nothing you should really worry about if it sounds ok, and you dont have the hit the tape harder, that whole nonsense is the biggest bunch of ignorance there has been written on the internet in pro audio circles. If the tape doesnt sound good, however, dont pass judgement on it until you put it through a proper bias and record calibration as you will probably find that it is going to react very differently with your machine than 456 does.

If you need help with the alignment process, just ask, its not very hard. I never found it very intuitive as a beginner, but its not very hard.

dave

dave

[msmith4060]

There you have it....

[mfdu]

dave, i need to learn how to bias my tascam 58 and 32 machines.

i am a very bad man.

i have the users manual (not that useful), but until now have simply opted for periodic servicing and setting for gp9 / 499.

would this be best as a new thread, or do you have somewhere you can direct me to for this info?

chris.

[soundguy]

hey chris-

I dont know what the story is with most of the tascam prosumer decks, you have to take them apart to get to the EQ controls so far as I know. Ive never set one up so dont think I can be that much help. If you could post what the rec/playback eq controls are perhaps someone can help. Not all machines work the same way, however all share the same principle.

dave