I don't think I have ever commented here for a variety of reasons but I felt compelled to write to you regarding your evaluation of the Nakamichi Dragon. Or upgrading your membership here though Paypal ( ). If you like this review, please consider donating funds to support these reviews using: Oh, well.Īs always, questions, comments, recommendations, etc. Worst of the worst digital products have performance that is hundreds of times better. Granted, the levels are low but 4.5% distortion? Phase and amplitude errors followed us here too.Įven though this is not a thorough test and the pedigree of test tapes is unknown, these results are more than depressing for those of us who cherished this marquee audio product. Widening of the 3 kHz tone at the bottom shows random jitter/tape speed variations. Increase in frequency has also increased our distortion. The Dragon is supposed to auto-calibrate the phase but clearly it is not able to do so. Likewise distortion components are just 40 to 50 dB down from our main tone as opposed to 90+ in digital.Ĭhannels are mismatched in both phase and amplitude. We are so used to SINAD (signal over distortion and noise) of 90+ that numbers like 41 dB seem so, so low! I unfortunately did not capture the results of 1 kHz tone but here are some other frequencies. The owner had a few of them and that is what I used for testing. Unlike digital products and amplifiers, we are at the mercy of calibration tapes for testing such products. The only possible exception was the Ampex ATR100, but I left Ampex just as that machine was being introduced, so didn't spend much time with one. I don't know of any machine that could support a frequency response at 0VU, unless that 0VU was deliberately done at low flux, relying on Dolby Noise Reduction to keep noise half-sensible. Frequency response also is very much flux related, on domestic machines it was generally measured at -20dB relative to whatever 0VU was, the better Pro machines used -10dB. Noise and distortion are trade-offs, and I remember some specs that played this, using different flux levels for noise (a high flux level) and distortion (substantially lower). I also entirely agree that terms like 0VU is meaningless without reference to the flux level. By far the greatest amount of noise and distortion comes from the record process, mostly the tape itself rather than the electronics. As part of that, I did a fair amount of work on record and replay amplifiers, and can confirm that replay amplification is very benign, similar in many respects to the more familiar RIAA replay amplifiers for LP playback. '0VU' is meaningless without stating the flux level the deck was calibrated for.Ĭlick to expand.My first job after University was partly designing electronics for high-speed tape duplication. With tape and deck 30+ years old.Īs an aside: all measurements should be referenced to a specific magnetic flux. Total A-weighted dynamic range is 68dB without Dolby! That is today. Something like a Sony Metal ES on a Nak CR-4 has less than 0.3% third harmonic at 400Hz at 218 nWb/m (DIN), and happily takes peaks 10dB over that for 3%. When I play a cassette recorded on deck B on deck A, I see the spectrum of B. When I play a cassette recorded on deck A on deck B, I see the distortion spectrum of A. In fact, some of these tapes were not even produced on a recorder, but on machinery imprinting specific magnetic patterns. No specific attention was spent on distortion during the recording of alignment tapes: distortion only had to be adequate so as not to endanger the tape's primary function. ) but a tape for replay distortion simply did/does not exist. playback level, replay azimuth, speed + wow&flutter, replay head height. Such tapes were typically made for one or two specific purposes (i.e. I also happen to have a lot of alignment tapes, the genuine stuff from ABEX, TEAC, and BASF, costing a small fortune. I do not have measurements for that.īut I do have other measurements for tens of decks and hundreds of tapes. Moreover, the stimulus would have to be equalised prior to injection, at least when multiple frequencies are used. This is very hard to do without picking up noise and hum, or sending the replay amp into oscillation. Proving by measurement that the replay side of things does not introduce distortion is a bit tough, as it would require me to disconnect the heads and inject signal straight into the replay amplifier at levels comparable to what a head produces, which is very feeble. It is well known that in magnetic tape recording the distortion (and compression and saturation) are caused by the combination of recording head and tape, and to a lesser extent by the recording amplifier if of incompetent design (which happened a lot).
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