Tape Machine Thread

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...Just realized I'm an idiot with quantitative prefixes... I actually had to look on a frequency spectrum chart to realize mhz is higher than khz...

But still seems plausible to capture this using software and a high sampling rate, right? And measuring azimuth as well I'd think. DO all of you guys use scopes?
 
Just be careful about being 360 degrees off when aligning.
Keith was talking about alingment at the old place, and the message I got from it was "if it ain't broke..."
You can think you have it aligned when the signals are really just offset by one cycle.
 
Brake Torque Adjustments:

This is one adjustment that I haven't performed before, so I will proceed with extreme caution; however, I think an adjustment is needed. Simply put, the forward direction is fine, but the reverse direction is VERY tight.

Here's the procedure in manual.

1. Check to make sure the brake arm does not come in contact recessed parts of the brake plunger.
This seems to be ok, but it's awfully close. But there is clearance. In fact, there is clearance until I spin the motor and the then it engages in reverse.
Solution if needed: Adjust hanger.

2. Manually operate brake plunger to be sure brake band is seperated from brake drum. Then turn the left and right reels motors by hand and check that they move freely.
As I stated before, forward is easy, reverse is tight. If I push up on the break arm a little they freely rotate in both ways.
Solution if needed: Ajust position of the break solenoid.

Then it goes into a procedure to actually adjust the break torque by measuring with a spring scale, etc. Doing a quick calc, the forward torque is too low and the reverse it way too high, but I think I need to adjust something in steps 1 or 2 before I can get accurate toque calculations.

I haven't made any adjustments as of yet... I guess I'm asking do I adjust the hanger (step 1), or adjust the break solenoid?

Please comment and advise.
 
[quote author="caps"]due to the massive magnetic pull of these cabs, is what I mean....if you have ever rolled one past a TV you will know what I mean....worried...[/quote]

That right there is your de-gaussing, in action! Or, actually, gaussing. The magnetic field put out by the speaker cab, is deflecting the electron beam, which is why the tv has a de-gaussing coil around the tube, which gets rid of the magnetic buildup, or tries to. Good idea not to leave it there too long, so it doesn't become permanent.

As far as damaging the tape deck, as long as you didn't get too close, or set it on the cab, I don't think it would hurt it. And, if it did build up a magnetic field, you would just have to de-gauss it again.

Make sure you don't have any tape that you don't want erased, near the de-gausser!

And, as Scenaria pointed out, 2" tape is IT! The only thing that might be better, is here: http://www.jrfmagnetics.com/index.html?JRF_mainframe=/JRF_relapping.html

Check out the "Ultimate Analog 2" 8 track"! The track width for 2" 24 trk is 1.0mm, but this thing gives 4.6mm for each track! I'm drooling just thinking about it! :twisted: :green: :sam:
 
I still haven't adjustments anything with the brakes, b/c I'm not sure what to do.

But I have an update regarding the oscillation I was having on track 1.

Here's what I've done:
1. Checked pinch roller pressure... it was within spec.
2. Checked edit tape tension... it was within spec.
3. Checked repro tape tenstion... it was a little low actually, so I increased it 10 grams on supply and take-up so now both sides are within spec.
4. My azimuth was over 90 degrees off, so I did a course adjustment with 1k, then fine tuned with 10k and 16k.

Results - When setting bias on channel 1, no more oscillation. Thanks primary to soundguy (and others) for all the help and the advise and "cautions."

I'd still like to deal with the brakes, but at least now I'm ready for a complete electrical alignment. Also, I'm still playing with bias levels. I think that 2dB overbias at 30ips sounds the best to me at the moment, but that may vary. My main concern is that I don't want the floor noise to be an issue.
 
in regard to leaving a tape close to a demagnitizer (degausser) i have done experiments to see if actually hold against a tape (also cassettetape) what happened and i shloudn't wurry too much!

I literally could NOT destroy what was on tape!
When holding the degausser to something iron like a small coin or whasher, it made it jump all around the place, so the degausser IS (or was) in good working condition.

the same with putting tape on a speakercabinet, i tried this experimentally by leaving tape a few weeks on top of a 4x12" without any (hearable) damage done. Didn't check for smpte etc tracks, as i'm sure these would have suffered from the experiments. I think if you wanted to damage on purpose, you would first have to leave the tape for a very long time and maybe sending material tru the 4x12" would create more (damaging) magnetism in the first place.

Just my 0,02 euro here, but based upon REAL tests

tdB
 
This really isn't a technical question... more of a usage one, but here goes. FYI - My tape machine is up and running great. No problems. Thanks guys.

So now to my question... My tape machine has peak LEDs on it. My last one didn't so I've never had to deal with this before. I started my first session (with the new machine) last night and I noticed that some of the drum tracks, especially the overheads and kick, were triggering the peak LED light before I was even getting in "the red" on the VU. So I wasn't really saturating all that much. So I guess there's some transient peaks in there. I'm assuming that I should try to limit these or something like that. I did have compression on my kick and snare tracks, but not the overheads. Please advise on the matter. Thanks.
 
I wonder what those LEDs are showing? Clipping of the output amps?

I have another question - can anyone tell me how to use a Tentelometer?
I found one in a studio's trash (works fine).
 
The relays on my 85-16 (orange legged one) are going bad. Esp. in the Rep/Rec cards/ I'm trying to source replacements. As far as I can tell, they are 12v, they are omrons and the number on the relay is G2V2. Part # in the manual is 6047048000, which, I think, is a teac/tascam number, not an omron #.

The part #I found from some anonymous guy on GS's is
OMRON G2VN-234PL 12 VDC

I'm looking for replacements, but can't seem to find anything, can't even find a datasheet on the G2V2 line to cross against. I know I'm not the first person to ever have to replace these things. Does anyone have a part number for a replacement relay?
 
If anyone in the UK is after some quarter inch tape I have a few 7inch spools of Zonal 675 that are surplus to requirements.

Cheers

Ian
 
unheardof said:
I have another question - can anyone tell me how to use a Tentelometer?
I found one in a studio's trash (works fine).
You are very lucky! Tentelometers aren't cheap! Unless it was in the trash because it was broken.
It should have three probes. Two are fixed, the third moves the meter. Thread the tape between the  two
fixed probes on one side of the tape, and the movable one on the other side.
The first thing is that you have to calibrate the meter for the size of tape you are using.
There should be a small 1 oz weight with the meter. Tie this to a peice of tape of the width that you are using. Then hold the tentelometer in one hand, thread the tape through, and let the weight drop so the tentelometer is reading. Then adjust it to read 1 oz. You should also have the right Allen key with the
weight in the case.
To use on a machine, thread tape on the machine. Put the tentelometer in the tape path where indicated
in the machine service manual, normally the peice of tape coming off/going on to the spool. read the tension. You need to move the meter around a bit to get the lowest reading.
 
soundguy said:
tape cal is pretty much I like chocolate/I like vanilla stuff.

Do you know how to cal the deck with confidence?  If so, here's my advice:

Record what you normally record while playing around with the hi/lo eq and the bias.  When you find the sound that you like, go and cal the machine to spec and make a note of how far off you were...  The most righteous kick drum sounds come from a track biased in a way that would make your vocals sound like garbage...  You can get very creative with your calibration and if you are doing everything in house it totally doesnt matter at all.  If you are going 9dB over bias, that could be some trouble for the machine down the line, but if you know what you are doing, cal'ing the deck so that not every track is totally flat can be used to your advantage.  Low freq head bump is your friend, figure out how to use it.  

If you dont know how to cal the deck, forget EVERYTHING I just said, you want to just get everything to spec and even and have a party without making a total mess...

All that said, you'll find a level that works for you, depending on what you record.  Ive told people in the past online who have asked about what level to cal their deck to and suggested that they just listen and people have had F*cking caniptions over that advice, but it really is the best advice.  I recorded on a standard cal for years before I came to the conclusion that I didnt like it as I never LISTENED to what it actually did to the tape, I just figured you had to do it that way or Lanoz the god of sound would materialize on earth and shoot lightning bolts out of your erase head at you...

If you dont know where to start, Q456 @ +6/185 nW/m is a sound that is pretty standard all over the world.  Depending on the integrity of the electronics of your deck you could try it at +9 if you have the bias to get up that high.  The tascam probably wont, I had an MSR-16 and +6 was all it had in it on a good day...  Check out GP9 @ +6/185.  Its a +9 stock but I dont like it at +9 at all.  You might love it...  It's totally chocolate vanilla kind of stuff. Forget what the tape wants (manufacturer spec and all that) and focus on what your specific machine can deliver for you with that tape.  Sort of like a porcshe with a professional driver vs. porsche with me driving...  Same car, same factory spec, totally different performance...

When it comes to the level you are gonna be working at, its really specific to the electronics in your specific deck, I dont care what anyone says about that, and believe me, Ive caught hell for suggesting such a blasphemous idea that +6 on my Sh*tty antique deck with rotting electronics sounds different than +6 on a different deck, etc...  Listen to what your machine wants to do, there's probably a window where you'll find what sounds REALLY good to you.  I have a new tape machine and spent three 12 hour days calibrating it this week.  Thats a really long time to sit on the floor turning tiny screws...  If you put the time in, you can solve a lot of problems if you custom tailor your calibration, but maybe thats a bit beyond what you are asking, I dont know.  The most important thing is to listen to what the deck is doing, just because some cal is cool on this machine dont mean its cool on another.  

My favorite story is the day I believed the hype about +9 for rock (for classical, sure) and brought an MM1100 up to +9, recorded kick and snare in my usual fashion and then proceeded to replace a handful of diodes on the record and playback cards that the drum tracks were recorded on.  This was around the time whe GP9 first came out and everyone was wearing those quantegy shirts with the needle bending on the VU and some slogan like "push it to the pins" or something like that, cant remember exactly.  

too much info maybe...

Just remember, for everyone telling you how end all be all a certain level is, the first handful of Led Zeppelin records were recorded at 185.  Thats ZERO.  If you can put balls like that on a tape at plus zero nW/m, that whole debate about level can more or less kiss my ass...

dave

very well said!
 
Ok, I dug around for a while and I've come up w/ this.

Here are the specs on the ones I'm replacing...
G2VN-234PL

I'm thinking these would work...
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=Z771-ND

Thoughts? Any advice would be much appreciated as I've never replaced a relay in my life.
 

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