R/E/P Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: 1 2 [3] 4  All   Go Down

Author Topic: Analog machine and tape maintenance  (Read 10528 times)

ssltech

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 4780
Re: Analog machine and tape maintenance
« Reply #30 on: January 14, 2006, 08:45:28 pm »

bobkatz wrote on Sat, 14 January 2006 14:48

Would love to see you Tuesday, Keith. Hope they'll look the other way and let them put in some extra chairs. Or is the company totally paranoid about that absurd fire department rule of a maximum of 49 chairs?

um... ahem...

I didn't hear you say anything about fire regulations, -did I? Wink

-Seriously, the room is the size of your usual multiplex theatre, and has three exits; 49 seems a little restrictive to me too.

-the installation is still not fully online, so we're not able to alter or break into the audio paths, hope that we have your understanding in that aspect, -but none the less, it's already promising to be a stunning room!!!

As far as pinch rollers go, you have to know the composition of the material -be it synthetic rubber, natural rubber or some other option- to know for sure what works, but frequent cleaning with distilled water will usually be fairly inert, though nowhere near as thorough as a strong solvent. -the trick is knowing what strong solvent won't also go to town on your pinch roller! Very Happy

Keith
Logged
MDM (maxdimario) wrote on Fri, 16 November 2007 21:36

I have the feeling that I have more experience in my little finger than you do in your whole body about audio electronics..

bobkatz

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 2926
Re: Analog machine and tape maintenance
« Reply #31 on: January 14, 2006, 09:53:57 pm »

[quote title=ssltech wrote on Sat, 14 January 2006 20:45

As far as pinch rollers go, you have to know the composition of the material -be it synthetic rubber, natural rubber or some other option- to know for sure what works, but frequent cleaning with distilled water will usually be fairly inert, though nowhere near as thorough as a strong solvent. -the trick is knowing what strong solvent won't also go to town on your pinch roller! Very Happy

Keith
[/quote]


I know you're supposed to know the composition... well, I've used 91% isopropyl for years on Studer, Ampex, you name it. I do seem to recall older Ampex pinch rollers going stiff. But the replacement pinch rollers made by ???? had no problems. The Technics are a miracle... 32 years with alcohol and NO problem. The synthetic pinch roller made for my Studer by JRF, alcohol, no problem, I checked. The moral of the story? I don't know. I've always used alcohol; either I've been lucky in the distribution of pinch rollers I've used and seen OR the potential degradation from alcohol has been greatly exagerrated.

I once saw one Otari pinch roller turn into dust, "sticky shed", disintegrate in the middle of a session!

BK
Logged
There are two kinds of fools,
One says-this is old and therefore good.
The other says-this is new and therefore better."

No trees were killed in the sending of this message. However a large number of
electrons were terribly inconvenienced.

ssltech

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 4780
Re: Analog machine and tape maintenance
« Reply #32 on: January 15, 2006, 09:39:56 am »

The Otari MTR-90 and similar rollers don't suffer from sticky shed, though it's a common supposition. The shed happens from the oxide face (the 'front') of the tape) and the rollers only see the BACK of the tape.

No, the problem with the Otari rollers appears to be some leeching into the material from the back of the tape. Under some non-scientific analysis, it appears to resemble some sort of carbon or graphite-like substance. This might make sense, since most manufacturers use some sort of dry light lubricant coating on the backing, to assist the pack in wind.

Anyhow, you're spot on in that when Otari rollers finally die, they go from being a functioning roller to something that's as useful as a chocolate teapot, stupendously fast! The replacement rollers like Athan corp products (and probably T-Reds and the like also) appear to be the sort of material that doesn't react with whatever the (presumed) lubricant is, and they can also be cleaned with alcohol without ANY deleterious effect that I've noticed.

There's a studio in Altamonte Springs right now that has a pair of A800s, one of which has a pinch roller that has dissolved in a very similar fashion: -Not something I see a lot of with Studers- and I have a replacement pinch roller here ready to go on it. -They never used alcohol in their rollers, and I'm actually wondering if the occasional alcohol cleaning wouldn't have done sone GOOD! -I mean, I suspect that a slight drying or de-oiling due to alcohol wouldn't have accelerated the problem, and might even have staved it off.

Keith
Logged
MDM (maxdimario) wrote on Fri, 16 November 2007 21:36

I have the feeling that I have more experience in my little finger than you do in your whole body about audio electronics..

ssltech

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 4780
Re: Analog machine and tape maintenance
« Reply #33 on: January 15, 2006, 09:46:01 am »

Oh yes, one hint to Otari pinch-rollerless owners: The RIGHT roller is the one that goes first, and the left one lasts several times longer. You can 'Rotate the tires' and even out the life. The right one does all the fast winding, play driving, accelleration and deceleration. -It is the brakes as well as the gas pedal, and it's the fast winding (or tather, the entry and exit to and from fast wind) that "stresses-n-stretches" the surface tread of the roller. The left roller is just the tape counter, and has no stress to speak of.

Swapping the rollers every few months evens out the life. Rotating the tires on a Front-Wheel-Drive car is a good analogy. in FWD, the front tires do 100% ofthe acceleration, 90% of the braking and take 75% of the turn lateral loading. Rotating the tires means that you change them all together, and you don;t get into solely age-related issues.

Keith
Logged
MDM (maxdimario) wrote on Fri, 16 November 2007 21:36

I have the feeling that I have more experience in my little finger than you do in your whole body about audio electronics..

thedoc

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1218
Re: Analog machine and tape maintenance
« Reply #34 on: January 15, 2006, 12:34:07 pm »

The Athan rollers work very well.
Logged
Doc

lek

  • Full Member
  • ***
  • Offline Offline
  • Posts: 109
Re: Analog machine and tape maintenance
« Reply #35 on: January 17, 2006, 12:39:14 pm »

bobkatz wrote on Fri, 13 January 2006 08:40


if you have an edited leader tape at the head of any song that's in the middle of the tape, you can stop there and then restart. We might not care if a piece of paper tape edge sticks out a little as long as it is not signal-containing audio. It is cheating though! And the library wind (constant tension) mode of the ATR 102 makes it so easy to just go back to the beginning and tail out that the issue is academic.
BK

Hi again. So you're saying if I've spliced some leader tape in the middle of a tape at the beginning of a song? I could just go back to that leader tape and then 'library wind' to the end from that point. Sorry, but I don't understand why starting at leader tape in the middle would be any different than starting anywhere else. BTW, since I am a first grader... no, kindergartner with all of this, I assume 'library wind' means winding it for storage?
scottoliphant wrote on Fri, 13 January 2006 15:26

Quote:

should I be losing that much top end
I wouldn't expect the top end loss to be that noticeable on a properly aligned deck. throw an MRL tape on there and check your 10K+ tones, maybe something goofy happened during transporting it around. If you switch over to GP9 at any point, also be sure to rebias your machine. There are plenty places on the net to read about how to do this (or you could ask us here if you ever feel the need).

Hi, it was just aligned at ATR. I'll try recording to tape again and note differences. By the way, similar to another thread (but I think more geared toward individual tracks), how hot a level might I want to record to the ATR - I'm guessing too low and there will be too much hiss, too high and I might start getting into serious tape compression (which I already did experiment with and found I pushed it too hard) - so, common sense, to my own aesthic taste?
Logged
don't forget to eat your khao niao

Lek
www.lekmusic.com

lek

  • Full Member
  • ***
  • Offline Offline
  • Posts: 109
Re: Analog machine and tape maintenance
« Reply #36 on: January 17, 2006, 12:43:37 pm »

bushwick wrote on Sat, 14 January 2006 17:39

Lek I am not sure if anyone told you this or not, but be sure to put your new tape on the take up side (the right side) "upside down" when you first get it and rewind it on the the supply side (the left side). After the tape has finished, then flip the reel so that you will get a true "tails out" recording. I didn't recall seeing this flipping through earlier posts.


Hi there. No, no one told me this - is everyone else doing this as well? What is the reason for "tails out" recording?
bushwick wrote on Sat, 14 January 2006 17:39


Which heads do you have on your machine? Stock ferrite or Flux Magnetics Extended response heads? I ask becauase that is going to affect your bias. Make sure you know.


I had them take off the ferrite heads, and put on relapped metal Ampex heads, not the Flux Magnetics. Thanks
Logged
don't forget to eat your khao niao

Lek
www.lekmusic.com

bushwick

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 624
Re: Analog machine and tape maintenance
« Reply #37 on: January 17, 2006, 02:03:38 pm »

Flipping the pancake and rewinding? Yes everyone using tape machines is doing this. You will walk into any studio and see the empty reel on the left - the supply side.

As for heads, the metal heads sound better than the ferrite heads or so the wisdom has been passed down to me. And your standard overbias chart listing the overbias figures will be correct. I asked because you might find something listing ATR machine heads with overbias figures but if you have Flux heads that will be incorrect. (The flux heads have a different gap and therefore a different bias headroom. I am not sure about the EMC heads but my guess would be yes.) 456 and GP9 bias differently so even though ATR set up yer machine for one, it will not be correctly set up for the other.

My suggestion is to get someone you know who uses that machine to come over and give you the run through on caling the machine and using your MRL tape. Even paying an engineer from somewhere nearby in Jersey is a very good idea. All of these questions you have will be answered and you will have some confidence that you are doing things correctly and most importantly, getting the most out of that beautiful machine. For example, it is important to watch someone who knows how, demag heads so you'll do that properly. Do it wrong, and you will magnetize them and screw up your masters.

Start yourself out right on the thing and then down the road you will be able to play with it and expand how much you can get out of printing to tape.

Best,
j
Logged
Joshua Kessler
bushwick  studio
brooklyn, ny
www.bushwickstudio.com

bushwick

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 624
Re: Analog machine and tape maintenance
« Reply #38 on: January 17, 2006, 05:07:37 pm »

Oh and you might be wondering:

456 is a +6 tape (over 185 nwb/m)
499 is a +9 tape (over 185 nwb/m)
GP9 is a +9 tape (over 185 nwb/m)

456 and 499 have the same oxide formulation, just that 499 has more of it and can handle more flux (more magnetism). GP9 is a totally different formulation and to my understanding, which could be flat wrong, its the same formulation as EMTEC 911. Anyone out there with info to speak to that?

At any rate GP9 sounds quite a bit different than the other two listed here and to my ears is quieter. I also find that it can handle even hotter signals than +9 pretty well, at least better than 499 - perhaps more of a tracking issue. Though for a project I recently did that was very acoustic (IEC1, 15ips, 499) we found that for some songs hitting the tape pretty hard helped the songs. Roughly speaking the sound closed up some causing the song to come across more focused and it gave some texture to the songs in question that certainly was not there before.

To my ears 456 has the smoothest knee when it starts to give and after only using 499 or gp9 for a long time I was really taken aback at how great it sounded to me - perhaps better than 499? Not sure. Maybe there is too much subjectivity to make any claims.

Hope thats helpful.

josh

Logged
Joshua Kessler
bushwick  studio
brooklyn, ny
www.bushwickstudio.com

James Perrett

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 339
Re: Analog machine and tape maintenance
« Reply #39 on: January 18, 2006, 07:56:57 am »

I thought that GP9 was the successor to 3M 996 - made after Ampex acquired 3M's tape business.

Cheers

James.
Logged
James Perrett - JRP Music - Audio Mastering and Restoration.
http://www.jrpmusic.net

Plush

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 264
Re: Analog machine and tape maintenance
« Reply #40 on: January 18, 2006, 12:56:58 pm »

jamesp wrote on Wed, 18 January 2006 06:56

I thought that GP9 was the successor to 3M 996 - made after Ampex acquired 3M's tape business.

Cheers

James.



Yessir!!
You are correct--although the formula is not exactly as 996 was. Quantegy  used the formulations and the different tape technology "know-how" acquired from 3M.

GP9  is an outstanding tape as is EMTEC 900.

We are awaiting the news that RMGI has new EMTEC 900 tape stock in their USA distribution channels.


Logged
Hudson Fair
Atelier HudSonic, Chicago

http://www.myspace.com/hudsonek

bobkatz

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 2926
Re: Analog machine and tape maintenance
« Reply #41 on: January 18, 2006, 06:24:20 pm »

lek wrote on Tue, 17 January 2006 12:39

bobkatz wrote on Fri, 13 January 2006 08:40


if you have an edited leader tape at the head of any song that's in the middle of the tape, you can stop there and then restart. We might not care if a piece of paper tape edge sticks out a little as long as it is not signal-containing audio. It is cheating though! And the library wind (constant tension) mode of the ATR 102 makes it so easy to just go back to the beginning and tail out that the issue is academic.
BK

Hi again. So you're saying if I've spliced some leader tape in the middle of a tape at the beginning of a song? I could just go back to that leader tape and then 'library wind' to the end from that point. Sorry, but I don't understand why starting at leader tape in the middle would be any different than starting anywhere else. BTW, since I am a first grader... no, kindergartner with all of this, I assume 'library wind' means winding it for storage?




You'll get it, Lek! What i meant to say is that if the edge of a piece of leader tape sticks out from the pack because you restarted a wind there, it won't be the worst tragedy if the edge of the leader tape gets damaged slightly from pressure. Library wind also means 'flat wound', no edges showing. You will see the first time you stop and then fast forward a tape that the first layer or two of wind might not pack smoothly.

I see in the rest of your post you said, "it was just aligned at ATR". Well, maybe it's just me, but I don't trust a machine's alignment that has traveled and shipped in a packing case.

BK
Logged
There are two kinds of fools,
One says-this is old and therefore good.
The other says-this is new and therefore better."

No trees were killed in the sending of this message. However a large number of
electrons were terribly inconvenienced.

lek

  • Full Member
  • ***
  • Offline Offline
  • Posts: 109
Re: Analog machine and tape maintenance
« Reply #42 on: January 18, 2006, 07:27:05 pm »

bobkatz wrote on Wed, 18 January 2006 18:24



I see in the rest of your post you said, "it was just aligned at ATR". Well, maybe it's just me, but I don't trust a machine's alignment that has traveled and shipped in a packing case.

BK

Actually, I, along with the help of some guy (actually my father), drove to ATR, loaded the mother in the back of my car and drove it back here - perhaps though I still need to realign it, twas a smooth ride, but obviously not free of friction and bumps.

Some other funky questions that have since bloomed forth -
actually, I'll save it for another thread...and I've experimented a bit more
Logged
don't forget to eat your khao niao

Lek
www.lekmusic.com

bobkatz

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 2926
Re: Analog machine and tape maintenance
« Reply #43 on: January 18, 2006, 08:58:07 pm »

lek wrote on Wed, 18 January 2006 19:27

bobkatz wrote on Wed, 18 January 2006 18:24



I see in the rest of your post you said, "it was just aligned at ATR". Well, maybe it's just me, but I don't trust a machine's alignment that has traveled and shipped in a packing case.

BK

Actually, I, along with the help of some guy (actually my father), drove to ATR, loaded the mother in the back of my car and drove it back here - perhaps though I still need to realign it, twas a smooth ride, but obviously not free of friction and bumps.

Some other funky questions that have since bloomed forth -
actually, I'll save it for another thread...and I've experimented a bit more



BTW, after a tape machine travels through lots of lines of the earth's magnetic field, the heads and guides should be demagged with the Han-D-Mag. Don't forget that the most residual, tiny amounts of magnetic field change are magnified by those preamplifiers, and so the machine is very sensitive, and equally so are the tapes you don't want to see self-erased.

Again, maybe it's just me, but that's the advice I give to people. If a machine travels, it should be demagnetized before playing.

BK
Logged
There are two kinds of fools,
One says-this is old and therefore good.
The other says-this is new and therefore better."

No trees were killed in the sending of this message. However a large number of
electrons were terribly inconvenienced.

Dominick Costanzo

  • Newbie
  • *
  • Offline Offline
  • Posts: 4
Re: Analog machine and tape maintenance
« Reply #44 on: January 18, 2006, 10:48:16 pm »

You'll notice that every reel of tape has a batch code on it. Quantegy codes show the year and the day of the year (eg. 2006017 = Jan. 17, 2006)
The best reason for rewinding a new reel of tape, then winding and storing it (tails out of course) on the reel it came on is to keep that batch code information with the tape in case of some problem down the road. This has come in handy more than once when I've had to return poorly slitted batches back to a manufacturer.
They always appreciate your help in identifying problem batches.
Studios using different stock on different projects also gain the security that tape on a Quantegy 456 reel IS 456, not EMTEC 900 or whatever.
Some may argue that rewinding the tape across the guides gets it "used to" the machine,  "preening" it so to speak. I've never seen any difference in tape performance whether it gets printed directly off the reel it was delivered or has been rewound.
Logged
Pages: 1 2 [3] 4  All   Go Up