04 December 2020

Cassette tape measurements: TDK D, A, FE, B

Introduction

This continues my evaluation of old cassette tapes, this time a bunch of TDK entry-level ferrics.

The details of the test methods are here.

INDEX OF ALL CASSETTES

 

Maxell UR C90 (1994) (what the deck was calibrated for)

Relative bias: (reference)
Relative sensitivity: (reference)
THD @ Dolby level: 0.42%
MOL400(THD=1%): +3.4dB
MOL400(THD=3%): +5.3dB
MOL1k(THD=3%): +2.9dB
SOL10k: -1.3dB
SOL15k: -7.3dB
Bias noise: -49.5dB, -52.5dB(A)
Dynamic range: 57.8dB


TDK D (1979)

Relative bias: -2
Relative sensitivity: -0.6dB
THD @ Dolby level: 1.4%
MOL400(3%): +1.9dB
SOL10k: -3.2dB
Bias noise: -48.4dB, -51.5dB(A)
Dynamic range: 53.4dB

Old it may be, but this D was in a great shape. The tape, a very pale brown, looked pristine. Its performance is not bad at all, with a bit less noise than early Maxell UL.

Later addition: I have by now tested ten of these cassettes, including their Kenwood N siblings. All of them performed flawlessly, after 40+ years.


TDK D (1982)

Relative bias: -2
Relative sensitivity: -0.5dB
THD @ Dolby level: 1.2%
MOL400(3%): +2.7dB
SOL10k: -2.6dB
Bias noise: -48.2dB, -51.1dB(A)
Dynamic range: 53.8dB

An evolution of the previous one. The same pale colour, MOL and SOL have increased a little bit, but noise too.


TDK D (1986)

Relative bias: 0
Relative sensitivity: -0.9dB
THD @ Dolby level: 0.7%
MOL400(3%): +3.7dB
SOL10k: -1.5dB
Bias noise: -49.5dB, -53.0dB(A)
Dynamic range: 56.7dB

An entirely different tape, with much better MOL, SOL, and noise.


TDK D (1988)

Relative bias: -2.5
Relative sensitivity: 0dB
THD @ Dolby level: 0.9%
MOL400(1%): +0.4dB
MOL400(3%): +3.5dB
MOL1k(3%): +2.3dB
SOL10k: -1.5dB
Bias noise: -49.6dB, -52.8dB(A)
Dynamic range: 56.3dB


TDK D (1990)

Relative bias: +1
Relative sensitivity: 0dB
THD @ Dolby level: 0.40%
MOL400(3%): +3.4dB
MOL400(3%): +6.0dB
MOL1k(3%): +5.1dB
SOL10k: -1.4dB
Bias noise: -48.7dB, -51.8dB(A)
Dynamic range: 57.8dB


TDK D (1992)

Relative bias: +2
Relative sensitivity: +0.3dB
THD @ Dolby level: 0.40%
MOL400(3%): +4.4dB
MOL400(3%): +7.0dB
MOL1k(3%): +3.7dB
SOL10k: -0.3dB
Bias noise: -48.4dB, -51.8dB(A)
Dynamic range: 58.8dB


TDK D (1995)

Relative bias: +5
Relative sensitivity: -0.1dB
THD @ Dolby level: 0.40%
MOL400(3%): +3.5dB
MOL400(3%): +6.0dB
MOL1k(3%): +3.4dB
SOL10k: -0.5dB
Bias noise: -49.0dB, -52.4dB(A)
Dynamic range: 58.4dB


TDK D (1998)

Relative bias: -1.5
Relative sensitivity: +1.0dB
THD @ Dolby level: 0.66%
MOL400(1%): +5.0dB
MOL400(3%): +6.8dB
MOL1k(3%): +2.6dB
SOL10k: -1.2dB
Bias noise: -49.5dB, -52.5dB(A)
Dynamic range: 59.3dB

My first sample of this tape, which may have been NOS, was troublesome, with a large channel imbalance and a rather unstable level. Then in June 2020 I found another one, in much better shape. The performance parameters of the two were the same, but the second sample was 0.9dB more sensitive. MOL is outrageous, so that its dynamic range ends up almost on a par with past TDK super ferrics. Another curiosity is that distortion remains below 1% up until very high levels. This is, electro-magnetically at least, a fantastic budget tape.


TDK A (1986)

Relative bias: +2
Relative sensitivity: -0.2dB
THD @ Dolby level: 0.40%
MOL400(1%): +4.0dB
MOL400(3%): +6.2dB
MOL1k(3%): +5.0dB
SOL10k: -1.0dB
Bias noise: -48.2dB, -51.5dB(A)
Dynamic range: 57.7dB

TDK's budget tape, slotted in below D. Curiously this is unlike any D, and in some respects better than its contemporaries.


TDK FE (1995)

Relative bias: +0.5
Relative sensitivity: +0.4dB
THD @ Dolby level: 0.47%
MOL400(1%): +4.9dB
MOL400(3%): +6.8dB
MOL1k(3%): +2.8dB
SOL10k: -0.8dB
Bias noise: -49.1dB, -52.3dB(A)
Dynamic range: 59.1dB

A more modern budget tape. Again unlike D, and very competent. This sample was manufactured in 1997.


TDK FE (1997)

Relative bias: +1
Relative sensitivity: +0.5dB
THD @ Dolby level: 0.30%
MOL400(1%): +4.5dB
MOL400(3%): +6.5dB
MOL1k(3%): +4.0dB
SOL10k: -0.5dB
Bias noise: -49.1dB, -52.3dB(A)
Dynamic range: 58.8dB

This sample was manufactured in 2002. The tape may well be the same as in the 1995 version. Outwardly boxes, cards, and shells appear to be identical, but the younger one lacks a hum shield.


TDK FE (2008)

Relative bias: 0
Relative sensitivity: -0.4dB
THD @ Dolby level: 0.38%
MOL400(1%): +2.8dB
MOL400(3%): +5.0dB
MOL1k(3%): +3.1dB
SOL10k: -1.0dB
Bias noise: -47.5dB, -50.6dB(A)
Dynamic range: 55.6dB

An FE from the Imation era. I don't know when this model was launched. The sample is from 2008. The tape differs markedly from the previous version, with lower MOL and much higher noise. Performance is very similar to other last-generation or modern-day ferrics (i.e. UR, Fox, ...)


TDK B fake? (2020?)

Relative bias: -1
Relative sensitivity: +0.4dB
THD @ Dolby level: 0.53%
MOL400(1%): +3.1dB
MOL400(3%): +6.0dB
MOL1k(3%): +3.9dB
SOL10k: -1.8dB
Bias noise: -47.4dB, -50.7dB(A)
Dynamic range: 56.7dB

I must admit I don't know for sure what this is. It was sent to me without its wrapper, but with the message that it is a Chinese fake, presumably like what can be found in abundance on AliExpr*ss and AliB*b*. The shell seems to be the same as the Onn cassettes sold by W*lm*rt.  That shell runs smoothly, and the magneto-acoustical performance is not bad at all!
There was one fly in the ointment: side A had a somewhat unstable treble, more so in the left channel, and this without any visible damage to the tape. That prompted me to set bias a bit lower. Switching to side B solved this, and that is how the above frequency plots were made. With hindsight leaving bias at 0 might have been better. I later learned that a weak side A left channel is typical for this cassette.




INDEX OF ALL CASSETTES







Cassette tape measurements: TDK SA-X, SA-XS



INDEX OF ALL CASSETTES


Maxell XLII 90 (1994)  (my calibration reference)

Relative bias: (reference)
Relative sensitivity: (reference)
THD @ Dolby level: 0.62%
MOL400(THD=1%) : +1.8dB
MOL400(THD=3%): +5.3dB
MOL1k(THD=3%): +5.5dB
SOL10k: -3.4dB
Bias noise: -54.8dB, -59.2dB(A)
Dynamic range: 64.5dB

The type II position of my Nakamichi BX-300 was calibrated for Maxell XLII 1994. All following results take this as a reference.


TDK SA-X (1979-1981)

Relative bias: -2
Relative sensitivity: +2.0dB
THD at Dolby Level: 0.77%
MOL400(1%): +1.0dB
MOL400(3%): +4.9dB
MOL1k(3%): +3.8dB
SOL10k:(no stable reading)
Bias noise: -51.0dB, -54.9dB(A)
Dynamic range: 59.8dB

SA-X was a premium type, but one has to wonder what then exactly this premium was supposed to be, compared with the early SA.


TDK SA-X (1982-1984)

Relative bias: +0.5
Relative sensitivity: +2.4dB
THD at Dolby Level: 0.56%
MOL400(1%): +2.4dB
MOL400(3%): +6.4dB
MOL1k(3%): +5.9dB
SOL10k: -2.0dB
Bias noise: -51.5dB, -55.1dB(A)
Dynamic range: 61.5dB

Despite some heavy railroading this tape still performed well, on both sides. Excellent MOL and SOL, but still not really better than SA of the same period.


TDK SA-X (1984-1985)

Relative bias: -1.5
Relative sensitivity: +1.6dB
THD at Dolby Level: 0.66%
MOL400(1%): +1.8dB
MOL400(3%): +5.5dB
MOL1k(3%): +4.7dB
SOL10k: -3.5dB
Bias noise: -54.6dB, -59.2dB(A)
Dynamic range: 64.7dB

Clearly the 1986 tape in an old-style shell. Probably near the end of the production run.


TDK SA-X (1986-1988)

Relative bias: -1.5
Relative sensitivity: +1.4dB
THD at Dolby Level: 0.65%
MOL400(1%): +1.8dB
MOL400(3%): +5.3dB
MOL1k(3%): +4.7dB
SOL10k: -4.3dB
Bias noise: -54.8dB, -59.2dB(A)
Dynamic range: 64.5dB


TDK SA-X (1988-1990)

Relative bias: 0
Relative sensitivity: +1.7dB
THD at Dolby Level: 0.40%
MOL400(1%): +3.9dB
MOL400(3%): +7.0dB
MOL1k(3%): +5.8dB
SOL10k: -3.0dB
Bias noise: -54.6dB, -59.1dB(A)
Dynamic range: 66.1dB


TDK SA-X (1990-1992)

Relative bias: +1.5
Relative sensitivity: +1.6dB
THD at Dolby Level: 0.34%
MOL400(1%): +4.7dB
MOL400(3%): >7.1dB
MOL1k(3%): +6.5dB
SOL10k: -2.5dB
Bias noise: -54.6dB, -58.9dB(A)
Dynamic range: >66.0dB


TDK SA-X (1992-1995)

Relative bias: +1.5
Relative sensitivity: +1.3dB
THD at Dolby Level: 0.45%
MOL400(1%): +3.7dB
MOL400(3%): +7.1dB
MOL1k(3%): +6.5dB
SOL10k: -2.5dB
Bias noise: -54.4dB, -58.4dB(A)
Dynamic range: 65.5dB

Almost as good as the 1990 version.


TDK SA-X (1995-1998)

Relative bias: -1.5
Relative sensitivity: +1.6dB
THD at Dolby Level: 0.54%
MOL400(1%): +2.3dB
MOL400(3%): +6.0dB
MOL1k(3%): +5.9dB
SOL10k: -3.0dB
Bias noise: -55.0dB, -59.5dB(A)
Dynamic range: 65.5dB

Bias flipped around, again, while MOLs and noise dropped.


TDK SA-X (1997-2001)

Relative bias: -1
Relative sensitivity: +1.6dB
THD at Dolby Level: 0.46%
MOL400(1%): +3.0dB
MOL400(3%): +6.5dB
MOL1k(3%): +6.3dB
SOL10k: -1.7dB
Bias noise: -54.5dB, -59.0dB(A)
Dynamic range: 65.5dB


TDK SA-XS (1992-1994)

Relative bias: +1
Relative sensitivity: +1.5dB
THD at Dolby Level: 0.52%
MOL400(1%): +3.2dB
MOL400(3%): +6.9dB
MOL1k(3%): +5.5dB
SOL10k: -2.4dB
Bias noise: -55.4dB, -59.8dB(A)
Dynamic range: 66.7dB




INDEX OF ALL CASSETTES