Setting Preamp, Outboard and Tape Machine Levels

[mikoo69]

I will be doing my first tape recordings soon and want to understand how to best set levels from the sources to the machine. I'm used to digital, where I would set the level on the preamp as high as possible without any digital clipping, watching the meters in Logic.

In the analog realm, how do I set levels?

There are meters on the consoles for the preamps. Then lets say I run a compressor between the console and the tape machine, how do I set the levels output of the compressor? And finally, setting the levels on the tape machine meters?

I understand with tape, it can sound good to push the levels and to focus on what I'm hearing off the repro head rather than simply what the meters are telling me, but I'd like to understand a bit more about how to set levels at each step of the way to get the best possible signal to noise ratio, sound, and also how to best read all the various meters.

[nick_a]

hey dude,

speaking only from personal experience, i'd say it'd be best to work backwards. Is the tape machine to which you are recording properly calibrated? If you see 0 db on the tape machine meter, is that actually 0db? Is that something that you're going to have to do, or is the tape machine someone else's/a studio's? I always start the day by putting up an MRL to make sure the meters are reading right, then put on a normal reel and print tones to make sure the record level is right for the tape formula and machine, etc etc. if that stuff is looking good, it's kinda just up to ears and common sense from there. Just my opinion.

[mikoo69]

I plan on calibrating/aligning the machine with MRL once I get some and figure out how to do it.

There is an SRL button on the Otari's channels (Standard Reference Level). Pressing this button uses a standard input level vs. setting it manually. Is this function useful?

I guess with the preamp/compressor, I should set the preamp level to sound good without the compressor in line, and then once the compressor is in line, use the compressor to fix the level, leaving the preamp alone?

[Snarl 12/8]

In analog, unlike digital (to an extent) you do get different, usable sounds by "pushing" the tape at different levels. It's going to be part of your aesthetic decision making which tracks to push how much.

BTW - you do know that the "as high as I can before clipping" mode of setting digital levels is very 90's. Ever since 24 bit samples, it's been more customary to try to print down 12-18 db so you retain all that beautiful transient info and to make summing easier, cleaner. But that's a whole other thread (or 50).

[jgimbel]

BTW - you do know that the "as high as I can before clipping" mode of setting digital levels is very 90's. Ever since 24 bit samples, it's been more customary to try to print down 12-18 db so you retain all that beautiful transient info and to make summing easier, cleaner. But that's a whole other thread (or 50).

+1 - I thought the same thing but I wasn't going to open that can of worms! I haven't been able to use tape in a long time with the exception of my Portastudio, so it's been digital for me, but it doesn't take long to see that "as high as possible without clipping" is not too good of a way to go. I read an article about that, not sure if it was Tape Op or somewhere else online, but it was entirely about how working that way makes a recording sound choked, and using more reasonable levels improves digital recordings significantly. Off topic though!

[Snarl 12/8]

It's almost the opposite now. Print to tape as high as possible without it sounding more squashed and distorted than you want to try to emulate digital's lack of hiss. Maybe also cause people are using tape more as an aesthetic choice, so you might as well slam it to get more tapiness. I'm venturing into talking out my ass territory here. I started on analog 8-track, but I don't think I've touched it since I started recording at 24 bits. (AKA a looooong time ago.) Not that I haven't wanted to recently.

[SafeandSoundMastering]

I am not going to suggest I am an expert in tape usage. However I did train up on an SSL 4000 G+ and a STUDER A800 a long whle ago. With HF sources I recommend hitting only -7Vu because Vu meters are not accurate at reading peaks in high frequency sources. So for hi hats, cymbals, percussion etc. peak lower and they will have less distortion on them.

cheers

Barry

[mikoo69]

what about the SRL option? I was told that once it's calibrated, the SRL button is useful as I won't have to mess with the levels at the Otari, only at the preamp/outboard. Is this accurate? Should I use SRL?

[Anthony Caruso]

I was told that once it's calibrated, the SRL button is useful as I won't have to mess with the levels at the Otari, only at the preamp/outboard.

Once the machine is calibrated, you should not have to touch it at all, SRL button or not. It isn't supposed to be another variable gain stage like the input level on a preamp or the output level of a compressor. You tell the tape machine what's what based on standards and you leave it alone. This is why you can take your tape recorded on a machine with known calibration and play it back pretty much the same on another identically calibrated machine, because 0 VU means the same thing to both machines. You're not adjusting the input or output of the tape machine as you record.

And the level relating to the SRL button isn't cast in stone, you would have to know that the SRL has been calibrated accurately to trust it.

Either way you should calibrate the machine before you do anything, which I think you are planning on doing. Is this at a hired studio? They should really either help you or even have it ready to go when you walk in the door. This shouldn't be coming out of your studio time, not from my experience, anyway. If it's like a favor or something that's one thing. If you (or somebody) is paying, and the studio is advertising themselves as an analog facility, they shouldn't just say, "Here's the machine. Good luck!".

In the analog realm, how do I set levels?

Before the tape deck, gain staging is gain staging... analog, digital, doesn't matter. Start at the source and work your way down the line.

I guess with the preamp/compressor, I should set the preamp level to sound good without the compressor in line, and then once the compressor is in line, use the compressor to fix the level, leaving the preamp alone?

Basically. Play with it though. See how adjusting each link in the chain effects the next. See what cranking the output of the preamp does to the compression. Turn the input of the compressor all the way up and the output of the pre down. Listen to how they are the same/different.

[witchfeet]

I have an Otari with the SRL button too. I'm 99.9% positive you want to push it in so that the track input level knobs don't do anything, set up your machine and don't touch that button. I believe it was an added feature that isn't really needed. I'm still learning about tape myself as well.

As far as levels into the machine, I think it's more a on a case by case basis as well as esthetic choices of how hard to hit the tape with a given signal. I have definitely noticed that the VU meters aren't all together trustworthy on the way in depending on what you are recording. I've had it read -8 or so when it's clearly getting much more signal than that. I was pushing it so hard my preamp was clipping but the VU was super low on the Otari. A quick test recording showed that it was clearly getting plenty of signal so I lowered the gain on my console and all was fine. So far I've just been experimenting and getting to know my gear and what will work with certain instruments, sounds etc.

Also, the VU meters need to be calibrated before you set up your machine, which i haven't done yet. Like I said I'm in the middle of learning myself. My machine was already set up for the tape I'm using so I've just been fooling around while waiting to order my MRL.

[cjac9]

I read an article about that, not sure if it was Tape Op or somewhere else online, but it was entirely about how working that way makes a recording sound choked, and using more reasonable levels improves digital recordings significantly. Off topic though!

This is probably the article. Good stuff!

http://www.massivemastering.com/blog/in ... Levels.php

[themagicmanmdt]

a caution about the otari tone generator in the tape machine -

i've seen a few that aren't matched, due to drift and/or miscalibration of that circuit. it's not crucial. don't worry about it. nice to have working, for sure! but, i'd say, pass on it for now.



if you're wondering about general signal matching for 'what is 0vu' and 'how does that relate to in the box' - yes, setting a sine wave at -18dbfs from the outs of your SC is a good rough but close point to what +4dbu is in the non-digital realm.

if you want to calibrate your gear to get really exact, grab a multimeter (you should get one if you don't have one!) - and a sine wave that measures 1.22 V (AC) is "+4".

to note - soundcards have an analog +4dbu source read anywhere from -20 to -14dbfs, totally depends on the make of the sound card.



lastly, you will most likely find, as well, that you won't have to ever worry about digital clipping, as the tape will saturate (9 times out of ten) before you get overs/clipping in digital.



and, yes, if you can, monitor off of the repro head when recording and when making final mic adjustments. it helps a ton, plus, playback off of tape isnt a 'surprise', and you can hear any quirks or machine problems or etc right away, instead of having 'that take' recorded and - whoops! - something's going on.



in short, tape it totally worth the headache.

plus, your machine doesn't have a dongle on the side of it.

[jgimbel]

I read an article about that, not sure if it was Tape Op or somewhere else online, but it was entirely about how working that way makes a recording sound choked, and using more reasonable levels improves digital recordings significantly. Off topic though!

This is probably the article. Good stuff!

http://www.massivemastering.com/blog/in ... Levels.php

That's the one!