Ampex Grand Master – 356/357

The Grand Master 356/357s are the tapes made famous for sticky shed syndrome, especially since for a long time their successors were the undisputed sales leaders for professional studio analog recordings in the 1970s and 1980s. All the trouble started in the mid 1970s with the introduction of their 20/20 and 356/357 “Grand Master” high output tapes. These were the first type 5 (high output +6) tapes produced, that later became the famous 456/457 master tapes. The MOL is so high that most older machines will reach their electronic limits before the tape distorts, which means most of the older machines cannot use their incredible capabilities. Notes:

• You can identify this formulation by its brown oxide and back coating.
• The 356 Series represents the SP (Standard Play) version and the 357 is the LP (Long Play) version with the same oxide coating. No DP or TP versions of this formulations were made to our knowledge.
• Unfortunately like many tapes of this period, the back coated versions suffer from Sticky Shed and cannot be played without baking. DO NOT PLAY OR WIND THESE TAPES BEFORE BAKING. Unless baked first, winding them can cause the oxide to be stripped from the polyester base material, essentially destroying them.  In fact, many batches cannot even be WOUND without baking as the oxide can be stripped off and the tape permanently destroyed. We have encountered some tapes that are less sticky than others, but there is no way to tell as the sticky shed condition seems to be dependent on the humidity of the environment they were stored in…and it has been over 40 years. If there is any valuable program material, these tapes need to be baked first.
• Available Refurbished: No we do not sell refurbished reels of 356 or 357 but some *might* be available used (sold without a guarantee) in our store that are available for collectors or research purposes.