I bought a set of 3 such cassettes locally along with 2 ferrochrom and a Cbox. The set was bought mostly for the 2 ferrochrom ones, but I was intrigued by the LH ones as I thought those were only TYPE I. There's no information that I can find online about this cassette and it's also a non-standard formulation because even in a deck with manual calibration adjustments (bias and rec sensitivity), I cannot get the correct levels even if I crank the pots all the way to the max (bias all the way negative, rec level all the way positive). While it is possibile that this tape has simply aged, I'm more inclined to believe a non-standard formulation, given how old it is (flat-head screws). It is clearly a TYPE II given the notch and the color of the tape, but that's all. Also I do not believe it to be a counterfeit (TYPE 0) because the other 2 ferrochrom cassettes in the set work great recorded on the TC-D5M. If anyone knows more information about this tape, please share !
There seem to be plenty of others for sale but I can't find the exact one on Vintage Cassettes https://www.ebay.co.uk/itm/134175801543 Zoom up and translate the inlay ? I wonder if it is something like TDK SA which were Type IIs that didn't use chrome.
Thanks for the reply ! The one in the ebay link looks to be a TYPE I, if you zoom in the first picture it can be seen that the tape color is a light brown. Mine don't have an inlay as they came with a BASF Cbox. This is what created confusion to begin with, as it seems this LH Super model existed in both TYPE I (orange label) and TYPE II (gray label) variants. As for TDK SA, that one has a dark brown tape, similar to SONY cobalt doped TYPE IIs (like the UCX, UCX-S, etc.). From my knowledge, BASF did its own formulations at the time and most older ones are pure chrome. An interesting fact is these late 70s models don't have anything wirtten about the EQ (70/120μs), while the newer ones like Chromdioxid do have this writing. Reading this article (https://audiochrome.blogspot.com/2020/03/cassette-tape-comparative-measurements.html), I think the closest one to the one I have in terms of tape magnetic properties is the BASF LH SM (1976) - picture attached. What the author says "I was lucky with this sample. I also tested another two of these, plus the 1977 variant (looking similar but orange on top and black below). Even at minimal bias none of them could record any treble, and midrange sensitivity was a low -4dB." corresponds with my own experience: even at minimal bias, the treble response is only half of what it should be. The low MOL of only -1.8dB would suggest it to be a pure chrome tape (typical of BASF), but even then it's very different compared to later ones like the BASF Chromdioxid or Chromdioxid II which can be calibrated to have a good response.
i have a whole box with older BASF‘s, i‘ll have a look later if there‘s one of those and test it then, as my RX-505 came fresh from service
rightyright, there we are. mine all have the original inlay and were most probably stored well. according to the inlay, the name SM means "special mechanics". the tape is brown, there's no indication anywhere if those tapes are 70 or 120 us, so i tried both variations - with almost no noticable difference (!). not even the use of Dolby B or C make a noticable difference, playing a bit with the Bias, you can get a bit more treble, bass-wise the tapes are quite ok - if i would have to judge those tapes with closed eyes, i would say, they're better than "normal"-type tapes, but not as good as my preferred Maxells... well, if i had the time or passion, i could make a proper lab-issue out of it, but i don't feel like it. if you want to test it properly, p.n. me your adress and i send you one of those...
Thanks for all the info ! Now I realise given the brown tape and the lack of a TYPE II EQ hole near the recording tab means your is a TYPE I. The Special Mechanism is something that I personally do not like and prefer to take out before using those cassettes, as I have seen YouTube videos where winding a NOS tape sheds off all the oxide layer from the tape. My guess would be that yours is similar to the later BASF LH Extra I (pictures attached), which given the more detailed information about EQ and type are newer. These LH Extra I actually perform very good for a TYPE I, only problem is they suffer from shedding a lot of oxide and squeeling. From what I have read it's a chemical binding agent problem, so a manufacturing problem. Hence the reason I didn't use mine much at all, cause from the 10-15 I have, only a handful are actually usable. I don't feel like making a lab-issue out of it either, but thank you for the offer of sending one to test. The chrome one I have remains quite a mystery. Probably an older chrome which has either degraded or is a very non-standard formulation, requiring a deck/recorder that has its internal adjustments set to this tape (which I will not do for 3 cassettes). It is however interesting how the early ones don't have any EQ info or tape type written on them, while newer ones have a lot more information.
