Welcome to the most visited website about analogue reel to reel recorders and magnetic tapes
reels - kind of tape - bias - cross reference list - care/handling - tape life - tape restoring - tapes for sale - sound qualityReels are wound on plastic or aluminium flange which diameter ranges from 3.1/4 to 10.1/2” for different playing time. Table below shows recording time referred to different speeds for standard and long, or extended, play tapes (one side only). You can use the table to covert the units of measure between the metric system and the Anglo-Saxon system and vice versa too.
Double (and triple too) play tapes with reduced thickness were available at the same reel diameter. They were more fragile and deformable than standard and long playing tapes and were not used in professional field.
There are three different types of reel supports and locking systems:
Is interesting to know German sound engineers, to reduce the print trough effect and have the recorded tape ready to play, wound the tape on the metallic core with the magnetic coated side facing the outside not the inside as international standard.
This is why the Telefunken Magnetophon M series are available in two different versions one for the international market (“A wind” version) and another one for Deutsch market (“B wind” version) with the head block turned down or up respectively.
Knowing the right kind of tape you are working on is very important in restoration to avoid damages due to wrong procedure. Different kind of tapes have different physical and chemistries characteristics and have to be treated in different ways.
Over the years different kinds of metal oxide were tested and used to improve tape quality reducing the signal noise ratio, print trough, distortion and improve dynamic. Each tape was slightly different from the other and every manufacturer suggested the different BIAS and level settings better fit their tape.
Basically speaking the so called BIAS, in magnetic recording field, is an high frequency signal (usually from 100,000 to 150,000 hz about or higher) recorded on the tape at the same time of musical signal. This principle, discovered in 1940 by accident, dramatically improves distortion and high frequencies response giving a very high quality recording.
The Bias frequency is even the same but its level has to be adjusted according to different kind of tapes and speed (see table below) for the best MOL (Maximum Output Level) with less THD (Total Harmonic Distortion).
This is why the reel to reel recorder has to be aligned according to the kind of tape used for the best recording result.
Table shows BIAS recommended setting reffered to Studer rec and play heads. It has to be used as guide only not as absolute reference for all the open reel recorders.
Most used tapes cross reference list both for recording and BIAS level.
Except Rmgi and ZONAL tapes still in production the most part of the above listed tapes are dismissed but sometimes you can find them used or NOS on the market. If you are looking for these kind of tapes be very careful: uninformed buyer can buy damaged or unsuitable tapes for music recording.
! BE CAREFUL ! AVOID:buying tapes for data or instrumentation use as Ampex/Quantegy 467 or 797, 799, and 3M/Scotch 8207. These tapes DON'T WORK FOR AUDIO USE.
Some other tapes not defective but poor quality are Sony SLH and AGFA PEM469 (which is nothing at all like very good 468).
At least: a basic difference in professional field is the high or low reprinting tape. High reprinting tape: expensive, high quality, low heads consumption but little echo effect on the blank part of tape (the so called "print through" effect). Low reprinting tape: cheap, low quality, high heads consumption but no or very low print through.
Magnetic tape is a strong enough support: you can record it several times and play back one time more, cut and paste with proper splicing tape for editing, but it needs some basic care suggestion.
The main problem is storage the tapes for long time at 40 to 90 degree F (average about 70° F) and relative humidity (40 to 60 %) as recommended by manufacturers. Sometimes it could be difficult to obtain both conditions in a non climate controlled room (like a cave or an attic where maybe you can find your dad tapes! :-))
To the contrary a well preserved, average used, 50 years old tape plays as brand new!
Magnetic tape is still the best archiving support ever made. It is safe and durable (still used in the airplane black boxes)
The real problem about life duration of all media supports, tapes included, is the faster obsolescence of the hardware to play them than the life of the support itself.
Magnetic tape doesn't came obsolete because RtR recorder can ever been built with standard mechanical and electronics components. Technicians and ordinary people go crazy these last years to store all their data every time a new digital system came on the market because of its incompatibility with the precedent one "built to last" . . . some months :-)
Do you remember what happened to the vinyl disc when CD arrived on the market? None factory build turntables more but there were millions vinyl discs still around the world to listen to.
The same thing happened with the reel to reel recorders production stopped when digital recording went on the market. But there are hundred millions hours of recordings on magnetic tapes, not only music but the entire human history of the last century is recorded on analogue audio and video tapes.
Vinyl discs have been discovered again these last years and now many factories are producing again every kind of turntable and vinyl discs.
Many tape recorders have been destroyed in the '90es but many still stay around, jealousy conserved by their owners or restored by technicians and audio analogue lovers like me.
They will became more and more precious in the future.
If you discover your tape is damaged might is not too late to play it again! There are some restoring and rescue methods to play a damaged tape just one time more to copy it or migrate to a digital support.
One of the most common problem are the "sticky" tapes. The method to restore “sticky” tapes comes from an Ampex patent of 1989 the so called “baking” tape procedure. This apparently simply method has to be accurately set in practice according to the kind and tape condition to avoid damage the tape definitively (CAUTION: AVOID TO USE WITH ACETATE TAPES).
Be careful using the grand ma oven or a dryer in a box because:
I'm fully equipped to read every kind of tapes without noise reduction system or with Dolby A, B, C, S, SR, DBX, TELCOM noise reduction units. I can process old no coded tapes with a professional denoiser too.
I can transfer analogue tapes into digital or new analogue tapes with professional analogue studio machine or digital A/D up to 24 bit 196Khz using worldwide acclaimed professional HiEnd Benchmark devices.
Feel free to contact me if you need tape restoring and/or a backup copy.
I have in stock news tapes, NAB adapters and many other accessories for open reel recorders.
Sometimes some recorder too.
Please refer to the UPGRADE - ACCESSORIES -SPARE PARTS page.
SOUND QUALITY: see ANALOGUE VS DIGITAL page.
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