Really?? I have never seen good enough tape head preamp circuits. My Nakamichi SR7 is full of cheap opamps. Too noisy as well, no?
No there isnt and its strange they didnt ever do that!!oshifis said:
VHS players do have smart rewind/forward meaning they SLOW DOWN as the tape gets near either end.... (Which is very good) -- I rmemeber the first VHS player we had in the 80s and that one DID NOT HAVE SMART REWIND/FORWARD and the tape would smash FULL SPEED @ the beggining or end... Not good i dont think for the tape!
The design includes enough friction on the takeoff reel obviously. Even with cheap players, such problems are usually with the takeup reel, i.e. "eating tapes."
Granted, "enough" is as ill-defined as "properly controlled," but there's no debate that the technology does work well, even if it falls short of the high end.
The Nakamichi CR-7 is nor a very good sounding deck, IMHO, sorry!
On all (properly working, obviously) dual-capstan cassette decks the supply side tension is controlled and the tape tension on the heads is stabilised by the dual-capstan transport. On some good quality single-capstan decks the supply side tension is controlled either mechanically or electronically.
A good quality cassette deck with a Type II or Type IV cassette can easily rival in sound quality a decent R2R at 7.5 ips. A special mastering 3.75 ips cassette deck can compete with a good R2R at 15 ips. I've used such a deck at several UK hi-fi shows as a second source in a £50K+ system. Nobody ever guessed from the sound alone that it was a cassette playing.
Cheers
Alex
Here comes my next question: how does a dual capstan transport work? I can't imagine exactly the same diameter and exactly the same rotation speed of the two capstans. A very-very tiny difference must exist due to mechanical tolerances. This should lead to overly tight or loose tape between the capstans over time. Or am I wrong?
There are two most common types of dual capstan transports, let's call these "Non-slipping" and "Slipping".
The first type is common in R2R decks, the second - in cassette decks. In the mechanics of the first type the capstan diameters, the pinch roller diameters and pinch roller pressure to the capstans are identical on both sides. The capstans rotate exactly with the same speed and there is no tape slippage on the capstans. This type works exclusively on the mechanical losses in the system. The capstan belt transfers the energy from the capstan motor to both capstans, and for that energy transfer there should be a difference between the belt tension on the supply side and on the take-up side. That difference depends on the mechanical energy losses (friction, pinch rollers and belt deformation etc.) . If the tape is present in the loop, than it runs "in parallel" to the capstan belt and takes some of it's tension on itself. This way the tape tension is well controlled without slippage and the whole system runs synchronously. Unfortunately, this system, though superior, requires tighter tolerances and for that reason only very few (and very good, coincidently) cassette decks use the "Non-slipping" dual-capstan mechanics: Nakamichi 1000, 1000-II, 700, 700-II, Sony TC-177SD, Technics RS-9900 , AFAIK - and perhaps few other decks too.
However the most common type of a dual-capstan transport for cassette decks is the "Slipping" type. In that type the supply side capstan rotates with slightly (0.1-0.3%) slower (linear) speed that the take-up capstan, the pinch rollers pressure is different too - very strong (300-500g) on the take-up side and much less (70-150g) on the supply side. As a result the tape continuously slipping on the supply capstan (to aid that slippage the supply capstan usually is highly polished and the take-up capstan is matt) and the tape tension is created by that slippage.
Cheers
Alex
Any of the cassette lovers wants this beast?
10x cassette player/changer
Hearbreaking to just dump it...
Rundmaus
10x cassette player/changer
Hearbreaking to just dump it...
Rundmaus
Nakamichi CR 7(A/E ) and same period machines like Dragon uses Low Noise FET input amplifier with really excellent S/N performance. Second most important factor is non pressure pad tape transport - scrape flutter is avoided and head wear is extremely small. And Sound ( using Dolby C in Nak)can match R2R 15 ips sound
They also workhorse machines - I use them regularly to listen to cassettes recorded 2 years back !
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