You can find some real bargains on blank tape on eBay, but there are some pitfalls to avoid. It's not a simple matter of how old the tape is, but also in what period of years it was made, how it was stored, and it's backing and polymer composition. Also, older tape formulations don't work that well on later or last generation tape decks.

 I've learned from my over 40 years of experience using tape as a professional and home recording enthusiast just what to go with and what to avoid.

Common Scenarios: These are the extreme cases that can happen.

1. Say you find an auction for some NOS Scotch 111 or 142 (Tartan) tape, and the boxes have the large Scotch logo, or, are in red boxes, indicating that these are from the early to mid 60's. The boxes are still in cellophane or plastic, and may even be in an unopened case. Seems like a good buy, but this tape is around 45 years old ! It is acetate backed, (as opposed to mylar) which can become unstable and brittle, and it's likely that the lubricants in the tape have dried up. The polymers in the backing that holds the iron oxide particles to the acetate tape, may have oozed and dried, causing the tape pack to stick to itself. In the end, you have a vintage reel and box, but no useable tape.

2. In another case you find some Scotch or Ampex tape from the mid 70's, good commercial formulas with cushioned backing (the black stuff on the back of the tape which is designed to dampen mechanical vibrations), and is NOS, still wrapped and in the case. Looks like a real good deal too, but much of the cushioned back tape from the mid 70's to early 80's used a (then) newer, cheaper, polymer that tends to absorb moisture causing it to expand and ooze from the tape edges, creating a problem known as 'sticky shed'. Tapes from this period are so sticky that they can (and will) actually jam a tape deck transport. After you clean off all of the black goo that the tape leaves behind on your guides and heads, you end up with a nice old stock reel and box, and no tape. ( If you have recorded tapes with this issue, they can be baked to dry up the ooze and make them playable for a short time).

I'm not saying that every NOS tape is going to be bad. If you want to buy a 45 year old box of tape for fun projects, (like making mixes to play on vintage gear), that's fine, but you don't want to trust old tape for any archiving purposes.  If you are archiving to tape, always go with new tape. I understand that both Quantegy and Emtec are back and under new ownership, and are now producing their full lines of mastering and general purpose tape (My Akai GX 747 is currently setup for Ampex/Quantegy 456). This is what I would buy for long-term conservation.

However, most of us ,I think, just want to record LP's and CD's to reel, for casual listening. Recording a CD to open reel can warm-up the sound, removing the hard digital edge. Recording LP's to tape can expand the dynamics and open the sound stage.

Some Good Vintage NOS Tape To Get

Just for example, Scotch 150 has been, in my own experience very long lived tape. I have some of this that is at least 35 years old, and hasn't exhibited any break-down at all. Other Scotch tapes like 203 and 207 are outstanding in performance and longevity as well. Ampex 351 is another one that ages very well, and seems to leave the heads and guides a little cleaner than the Scotch 150. Audiotape, Maxell, TDK, Irish, American, Sony, and even some Realistic and Supertape (Radio Shack) tapes all do really well in weathering the ravages of time.   

Of course, the best NOS tape to get (provided your deck is set up for it) is Maxell UD 35-90. Outstanding perfomance and long life is assured from the quality of manufacture. I can never recall getting a bad reel of this stuff, and I still have many that I use.

Some Tapes To Avoid At All Costs!

This mostly pertains to 'white box' tape, as it was once called. Much of this is recycled tape, or the unused remnant cut near the edge of the master tape roll (tape rolls are generally about 8 feet wide, with the best part being in the center, and the lower quality stuff near the outer edges) . White box tapes include brands like Radio Shack's Concertape (the 1.5 and 1 mil tapes are mostly used studio tape), Shamrock (used computer and video tape), and most in-house brands sold by Sears, Wards, (edge remnants) and many drug, hardware, and grocery stores over the years. Many independent electronic stores and mail order companies would order up white box tapes, and put their own names and graphics on the boxes.  All the graphics on the boxes expound that these tapes are professional and splice-free. Don't bet on it. Many of those sold in the 70's will be used studio tape with splices and sticky shed issues, and the rest are recycled computer tape and video tape that will not record well as the bias on your tape recorder is much lower than is required for those formulations. The result is a loss of lower frequencies, and low volume on playback.

 White box tapes that are edge remnants tend to be very good for general purpose fun projects. Scotch had it's own 'budget' brand that they called the Tartan Series. These had their own tape formula numbers (141,142, etc) and came in a blue on white box, and were almost as good as Scotch 111 or 150 (and impossible to tell the difference on consumer gear). All major manufacturers sold-off  their edge cuts to third parties or had their own sub or discount brands.

 The big one to avoid are any of the major brand tapes with cushion backing from the mid 70's to early 80's by companies like Scotch (226 especially, and I have been told the same is true for 227), Ampex, Maxell (UD-XL II), TDK and others. These will most certainly have succumbed to the sticky shed syndrome.

Used Tapes

 I see these all the time being touted as 'recorded on only once', but no statement as to how many times they have been played. Good high grade tape that has been recorded as a master and stored, and not played repeatedly would be fine for a fun project but not for long term archiving. Tapes that were recorded once and played many times will only be as good as the transport they were played on, how well maintained the tape deck was, and how the tapes were stored.

Another issue with used tape is when a bulk eraser is used to clear the tape. This isn't a bad thing in and of itself, but most people don't know how to use a bulk eraser properly, and this can result in a permanent swirling sound on the tape that sounds somewhat like ocean waves or repetitive 'whoosh'  type of noise. To properly erase a tape, you have to turn the eraser on or off with the tape at least 3 feet away, otherwise a strong magnetic impulse hits the tape, and becomes a permanent part of it. This results in greater noise level, and changes the way the tape will take a recording. I have seen supposedly knowledgable people throw a tape on an eraser, and hit the power, thinking nothing of it!  Make sure the seller knows what he's doing.

Buying used tape is always a crap shoot, and unless you are going to use tapes like this for totally expendable content, don't waste your money on them.

If you need extra reels and boxes this is an inexpensive way to acquire them. Spool the tape into the trash, swab the reel, and load your fresh tape into it. 

Which Tape Will Give The Best Performance?

This comes down to just what kind of tape your deck is set up for. Just for the sake of argument, let's say you have a Teac 4010S (probably the single most popular tape deck ever made). It was set up from the factory with Scotch 111 as a baseline (this deck was setup for one tape type only). Other tapes like Ampex 351,  the rest of the Scotch line, Audiotape, and any other 'normal bias' tape will work and sound great, with small variations in the reproduction, as they are similar in primary composition but slightly different in spec.

 Using something like a Maxell UD 35-90 will work fine, but you might notice the highs are brighter, the lows are a bit subdued, and it is louder on playback. The Maxell UD series and the TDK SD series require a slightly higher bias and slightly different EQ from the other formulas, but not so much as to prevent you from using them. The later Teac 4010 SL and GSL were setup with Scotch 150 and Maxell UD35-90. There is a selector on the deck to go from 'normal' (Scotch 150) and 'High Bias' (Maxell UD 35-90). The majority of good decks had this feature.

 Many decks made from the early 70's through the 80's used Scotch 150 or 203 and Maxell UD 35-90 for bias and EQ setup baselines at the factory. The majority of service manuals I have read on Akai, Teac, and other indicate this.  By using these tapes as the baseline the tape deck manufacurers allowed the end user access to a wide variety of compatable tapes with similar formulas that would have different audable qualities. That's why some brands of tape may sound a bit warmer and open or brighter and tighter, depending on what the deck is the up for.

 Early and single bias tape recorders (1948 to about 1967) will do best with standard iron (red/brown) oxide tapes like Scotch 111, 141, 142, 150, etc. and some of the later black oxides for normal bias. My old Sentinel Model 10 (1954) sounds best with red/brown oxides. It makes sense as that's all that was around when it was made and setup. However, I used to own an old Pentron from about 1952, that worked unbelievable well with newer black oxides better than it did with Scotch 111 or 150.

EE Tape

Maybe you've seen this on the bias selector on your recorder and didn't know what it was. EE type tape, is basically chromium oxide (Cr02) tape, as used in high bias cassettes. It was a last ditch effort by open reel maufacturers to raise the format above all others. This combined with DBX noise reduction was as good as it got for home audio at the time.

Unfortunately, this did not last very long. Nobody was buying the new machines and tapes in any great numbers, as cassettes had become the tape format preferred by most people (who were, by and large, non-audiophiles). When you can find EE tape, it is generally only on 10.5 inch reels, and sells for a very high premium. My primary deck is an Akai GX747, and it was set up for both EE and Maxell UD 35-90 (it is now setup for Ampex/Quantegy 456), but I have never used EE tape, purely because of the scarcity.

For high-end audio applications, if necessary, it would be a good idea to have your deck setup to use new tape from either Quantegy or Emtec. If you try out some of these tape formulas and it sounds good (no difference between the source and the tape) then you are good to go. If the tape sounds muffled or overly bright, it's not the tape's fault; your deck is not set up for it.

Setup to a specific tape formula affects the record function only. Once setup, the tapes you make will play well not only on your deck, but on any other tape deck as well.

 If you are in a metropolitan area, it should be no great task to find a technician to setup the bias and EQ on your deck. Those of you in the sticks will have to pony up shipping to get your deck to a qualified pro. Don't be tempted to allow a shade-tree technician play with your tape deck's innards!

Antique Tape

At the beginning of this guide, I pointed out some major pitfalls associated with buying very old tape. This was a worst case scenario, and it does not always end up this way. I've bought some very old tape  (55 + years old) to have as examples, and was surprised to find that the tape was still very much viable.

When dealing with the old stuff, just be vigilant when you play or record on it. Is it shedding excessivly? Is there a high pitched squeal coming from the transport? Is there fuzzy stuff left on the guides?

Excessive shedding means that the polymer has dried up and blown away. If there is content on the reel you want to keep, copy it immediatly.

Squealing occurs when the lubricants have dissipated from the tape. The good news is that there are treatments available for this, and can make the tape as good as new.

Fuzzy, lint-like matter accumilating on the tape guides indicates that the polymers have oozed certainly, but it may be an indicator the the acetate backing is losing it's plasticizer, and will eventually become too brittle to play. I can't say for certain, and while I have had contact with some experts on this issue, I've yet to get a clear answer. I'm not a chemist, so this is an educated guesstimate.

Sticky Shed Syndrome

As I mentioned before, this is largely in cushioned backed tapes from the 70's to early 80's. These tapes are unplayable, but can be made temporarily playable by baking them in a lab grade convection oven for 12 to 24 hours at 150 degrees. The tape will be playable for anywhere from 12 hours to upwards of a month in some cases. The tape should be copied either to another tape or to digital as soon as it has cooled off.

 Now if you don't own a lab grade convection oven, but want to try a DIY method, I've got one and it worked very well. If you live in a warm climate, during the summer months the interior of a car attains suitable tempartures for this task. I placed my reels under the sun visors (visors in the closed position, so that the open tape box was wedged against the car's ceiling) and left them there for a weekend. The result was playable tapes! Just don't let the tape become exposed to direct sunlight in the process. Also, I take no responsiblity for any adverse effects you may experience such as damage of any kind to your tape, your car, or your feelings.

This, like my other guides, is a work in progress, and I hope to compile my acquired knowledge into a book someday soon that someone will publish, so that the layman can have a reference for his home audio applications. There are literally no good reference works available for the home stereo hobbiest. I do hope you found this helpful, Cheers!