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In Reply to: Expectations re R2R headwear? posted by little help? on December 15, 2006 at 16:50:58:
In a word, no. There are different types of heads. There are also several variables that come into play that can affect the longevity of heads as well.
For starters, so-called "permalloy" heads are relatively softer gauge of metal and are probably the shortest lived of heads.
Next would be the so-called "sendust alloy" heads. These are somewhat, but not a whole lot harder than "permalloy".Most common would be so-called "amorphous" heads. So called because they were said to be made with iron particles with random or shapeless orintation. Hence the name.
And finally there are the so-called "crystal-alloy" heads. To my knowledge, only Akai used them on their R2R decks and were claimed to have an indefinite usage life. I have not read any reports that substantiate nor debunk that claim. I will say, however, that out of the 4 or so Akai decks I owned, none of them ever showed any discernable headwear grooves.
I'm sure there are other types of heads out there that I've forgotten.
Comparing the life expectancy of cassette versus reel to reel tape heads is to a large extent apples-to-oranges. Just look at the speed differentials. Most cassette decks operate at 1 7/8 ips. Reel to reel decks operate from that speed all the way up to 30 ips, although most of them are used at either 7 1/2 or 15 ips. It doesn't take a whole lot of common sense to figure out that, well, the higher the speed, the faster it's likely to wear out. Simple physics makes that an all but irrefutable point.
Other things to take into consideration that can seriously shorten the life of your heads is 1) how often you use high-speed audible cue or AMS. This feature keeps the heads engaged while running the tape at fast-wind speed. This is brutal to the heads (and can blow a speaker or fuse if not done right). 2) How often you clean the heads. Oxide buildup, especially if left untreated for some time picks up dust. And oxide, unlike the calendered surface of tapes, is clumpy and randomly shaped. So mix it with dust and it's like running steel wool across the heads. This too shortens the life. And 3), what kind of tape(s) are you using? Are you using high grade premium tape-which is mirror smooth-or are you using low grade ferric that is likely to have a more irregular surface?
Using cheap tape, while cheap up front, will also grind your heads down considerably faster.
In summary, there is no hard and fast gospel rule that I know of that specificallly dictates how long a head should last. But the better decks will usually have better heads. If you use good tape, use the cue features sparingly (or not at all), and keep them clean, then in all probablity, the decks bearings will fail before the heads do, regardless of format.
Hope this helps.
Follow Ups:
I understand one can’t say with absolute certainty but could fully rewinding a 10.5 reel 2-3 times while in AMS or cue mode wear out otherwise perfectly good heads? Theoretically speaking of course .
Very hard on tweeters! You should have tape lifters that lift the tape off the heads on fast forward or fast rewind and a mute to ground out the play preamp on fast forward or fast rewind.
"I take you as you are
And make of you what I will,
Skunk-bear, carcajou, bloodthirsty
Non-survivor.
Lord, let me die but not die out." THE LAST WOLVERINE by James Dickey
Can you tell me what type heads are in my Teac X1000R? I'm still using the originals in a machine bought new in 1984, and a fingernail test indicates some wear but not as much as I would expect. Does anyone re-lap these things, or are new heads the only option down the road? TIA, Dave
Dave,Headware will result most noticeably in loss of high frequencies. Because it happens slowly over a long period of time, you might not even notice it till it becomes severe.
A reproduce test tape and meter will show up a problem in a second - assuming you measured the response when the deck was new - or trust the original specifications.
Relapping may restore the highs - depends on the head.
The headware pattern can also head mis-alignment.
The highs remain excellent on my machine (when they're on the tapes in the first place).Which may only mean that in my declining years, the high frequencies are going at the same rate as the tape heads. How's that for planning ahead?
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