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Vintage Tape (Audio), Cassette, Wire and Magnetic Disc Recorders and Players Open-reel tape recorders, cassette recorders, 8-track players etc.

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Old 2nd Dec 2022, 3:40 pm   #21
stevehertz
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Default Re: Pure Chrome tapes

I mean, reading what 'everyone' has to say they do seem to be problematic one way or another.
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Old 3rd Dec 2022, 12:06 pm   #22
Ted Kendall
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Default Re: Pure Chrome tapes

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Originally Posted by knobtwiddler View Post
If you suspect a tape has lost a few dB, then it makes sense to copy it to digital without Dolby, and apply it using a Dolby plug-in, whereby you can adjust the threshold.
Quite agree, except that there isn't a Dolby plug-in that really works, in my experience at least. Irksome as it is, a decent external Dolby is the best approach to post-dub processing, even with the additional d-a/a-d conversion. When you've got a Prism, that doesn't matter...
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Old 3rd Dec 2022, 12:10 pm   #23
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Default Re: Pure Chrome tapes

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Originally Posted by paulsherwin View Post
By the time metal cassettes had been developed, pseudochrome technology had advanced so much that the quality improvement was only marginal. They were significantly more expensive, and there were some reliability issues, at least in the early days. They never really went mainstream, at least in the UK.
Stupendous marketing boost for the machine manufacturers, though - overnight the entire stock of machines sold to date became obsolescent, although I agree metal cassettes turned out to be a paper tiger. I found SA plenty good enough for what I did with cassettes.
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Old 3rd Dec 2022, 12:14 pm   #24
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Default Re: Pure Chrome tapes

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Re the earlier discussion on Chrome tapes having over time lost their ability to make good new recordings nowadays, this is a new one on me which Ive been trying to understand. If it's the case one would have thought the mechanism of degradation would have been discovered by now. I wonder if the alleged shifting bias and sensitivity requirements from the pseudochrome tapes, were the differences that were always there from new and some have simply recently discovered these inherent differences themselves.
Perhaps the machines being used to make the tests have deteriorated with age, or more modern ones just don't have the oomph to drive pure chromes fully - almost any cassette machine designed less than twenty years ago is heavily value-engineered, to put it politely.
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Old 4th Dec 2022, 1:40 am   #25
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Default Re: Pure Chrome tapes

As far as I can make out from reading the relevent comments on another forum, the later pseudochrome cassettes required more bias than the original chromes, but less pre emphasis. So basically a recorder ideally calibrated to a chrome tape would need to have its bias reduced and its pre emphasis boosted, both re pseudochromes. I have cassette decks where bias can be easily changed, but I dont think I have one where pre emphasis can be easily changed, as it can on pro reel to reel decks. Maybe this is part of the problem generally. I guess an auto calibrate deck would have a better chance if it altered both bias and pre emphasis, as well obviously as record gain, in its calibration routine. I've had very little to do with chrome cassettes so again this is new for me.
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Old 4th Dec 2022, 1:58 am   #26
Bazz4CQJ
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Default Re: Pure Chrome tapes

The thread seems to focus on the old 1970's BASF Chromdioxid tapes, but there's also BASF Chrome tape Called "Pro II", which may be a much later product. I've never tried them; has any else?

I bought a used Harmon/Kardon machine a while ago and the BASF Pro II tapes are on the preferred list for that, though they called up TDK SA as their reference Cr2O3 tape

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Old 4th Dec 2022, 10:14 am   #27
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Default Re: Pure Chrome tapes

I vaguely remember that BASF made some sort of pseudochrome tape towards the end of their time as a manufacturer. Maybe they finally came to terms with the industry. I don't have any experience with these tapes.
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Old 4th Dec 2022, 4:39 pm   #28
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Default Re: Pure Chrome tapes

I just took a look on ebay; first impression is that BASF Pro II was/is a North American thing. Lots for sale there but none in the UK. Here, there's a BASF tape called 'Sound II', which might the European badge?

But on a machine referenced on SA, no great incentive to try.

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Old 4th Dec 2022, 4:52 pm   #29
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Default Re: Pure Chrome tapes

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Originally Posted by Bazz4CQJ View Post
but there's also BASF Chrome tape Called "Pro II", which may be a much later product. I've never tried them; has any else?
Sold many BASF tapes up until the mid 80's, Pro II is not one I recollect. Appears to be a product marketed in the USA c.1980/81 according to 45worlds database.

https://www.45spaces.com/audio-compa...hp?r=aud487826

Never really a fan of BASF after a lot of issues with their 1970's offerings such as dropout and oxide shedding, but from about 1980 they overcame these problems. BASF CR-E II was excellent and correctly biassed did marginally outperform many contemporary pseudochrome formulations.

https://www.45spaces.com/audio-compa...hp?r=aud826970

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Old 8th Dec 2022, 12:54 pm   #30
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Default Re: Pure Chrome tapes

A few things to bear in mind:

USA BASF products from the late 70s into the early 80s specifically had dreadful quality control which was sorted some time around 1982. That lead to BASF gaining a poor reputation in the USA from which they never recovered even though the tape made for the rest of the world was universally excellent. There was also an outright lie spread by 3M regarding BASF professional video tape which spread to include BASF audio tape and cassettes, regarding CrO2 damaging heads. This was a quickly debunked lie circa 1980 but still persists to this day.

There is a drop in sensitivity of a few dB over the first 3-5 years of a CrO2 tape's life. thereafter it should remain stable. Careful (or automatic) calibration can still bring these older cassettes to make excellent recordings. If you have a Yamaha KX deck you also have "play trim" which adjusts the playback EQ before the Dolby circuit to further help compatability.

There was and remains nothing wrong with CrO2 cassettes when used as intended. The problem is that the Psuedochromes are used in a different manner and most people became used to them rather than genuine chrome cassettes. Recording technique is simply different.

CrO2 gets a bad rep for all the above reasons. But the fact remains that if you use it as intended, it's still great. Far lower noise floor than any other cassette tape formulation ever devised.

Type IV metal cassettes had a higher noise floor than types I or II but could also take higher recording levels and record slightly higher frequencies. Ultimately they were the best *if* you had a deck capable of exploiting their strengths. Which was generally the mid to top range decks with better heads and beefy bias and record amp circuits. Not just any deck with a type IV switch. Even then, a good type II (chrome or pseudochrome) would probably give 95+% the performance of a type IV.
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