Compact Cassettes.

Discussion in 'Audio Hardware' started by colby2415, Jul 12, 2017.

  1. colby2415

    colby2415 Forum Resident Thread Starter

    You might remember from a few weeks back that I had a sony tape deck in need of repairs. Anyways, I have finally received it back from the repair place and everything is perfect. The model of deck is the sony tc-k15 and it appears to be a entry level deck from the late 70s. Anyways, it only has dolby B (the newest at the time I believe) and I was wondering what that means when it comes to pre-recorded cassettes. Most cassettes I have are blanks but I do have some pre-recorded stuff I might want to listen to from time to time. Anyways, most of them just say "dolby nr" but I do have a few (like the steely dan greatest hits which uses. dolby hx). I was wondering what is the best way to play these back? Would it be better to use the dolby b or just turn it all off? When it comes to recording I plan to keep it off cause I have heard that it chops the top end off in some cases. Also I assume it would not be possible to use metal tapes? I only have the selector for type 1, 2 and 3. If I am limited to the 3, which would be the best choice for the highest possible quality recordings?

  2. Methodical

    Methodical Well-Known Member

    I turn all noise reduction stuff off and just play the tapes. NR, to me, make the music sound muffled.
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  3. c-eling

    c-eling Forum Resident

    Same here...
    If you have any favorite artists on the Capitol/EMI label, try looking for XDR editions
  4. colby2415

    colby2415 Forum Resident Thread Starter

    what are XDR editions? do they not have noise reduction or something like that?

    Seems like the general consensus. I never really found the hiss to be a bother in the short time i had the deck before it broke down, so I'll probably just not bother at all with it.
  5. 56GoldTop

    56GoldTop Unapologetic Music Ho

    If the tapes and your deck are in good condition (and electrically aligned to spec or better), playing them back with Dolby NR should not yield a muffled HF response. If it does (and again, if your tapes and deck are in good condition) the most likely culprit is your playback head azimuth (not matching that of the record head used to produce the tape). This is the reason for NAAC (Nakamichi) and MAAC (Marantz) auto-azimuth systems, as well as the very few other decks that offered front panel manual playback head azimuth. Nevertheless, if you are handy with a jewelers screwdriver, PB head azimuth can almost always be adjusted. I have a dedicated playback deck which I use to archive cassettes. With a very slight turn of a screw, I have gotten maximum performance (lively HF and solid LF) with Dolby NR activated from cassettes that many probably would have tossed in the bin. And, as the raison d'etre for Dolby NR, hiss largely removed.
  6. colby2415

    colby2415 Forum Resident Thread Starter

    Yeah, i remember seeing something on this too. I am not sure if the technician who did the work did this, but it might be worth it to find out. If it is something that you can do yourself, do you have any resources or how-to's that I could use? I imagine it can't be much different than cartridge alignment
  7. 56GoldTop

    56GoldTop Unapologetic Music Ho

    It's really not.

    Most importantly, I would say, you need two things: an owners manual (to know where the PB head azimuth screw is and how to remove the door or "door panel", on some decks this isn't necessary) and... ...your ears. If the deck is properly aligned electrically, turning the azimuth adjustment screw, with Dolby NR engaged, and a tape playing should give you a result similar to a tone knob. You should hear the treble increasing or dropping off. Going for maximum treble is probably not what you want. It should sound "balanced". Also, be careful to listen for the beginnings of "tape chew". If you do, immediately reverse course or stop the deck. No sense ruining the tape. Many tapes can be saved; but as with anything else, some tapes are beyond help and defy adjustment (warped shells (transplanting into a new shell may work), too much oxide loss, etc.). Toss 'em...

    The caveat to this is, you should have a reference as to where "zero" or "home base" was. A test tape is preferable. In lieu of that, I would use a tape that you know the sound of very well; so that, after adjusting for a particular tape, you can reset the head back to where it was. Most techs will "seal" the adjustment screws in place to lock them in. However, if you want to dial in each tape a la Nakamichi, Tandberg, Marantz..., that will have to take a back seat.

    Sony TC-K15 Manual available at HifiEngine

    ...and it's got analog meters! Nice.
  8. JohnO

    JohnO Forum Resident

    Washington, DC
    Dolby HX was used only in recording, and was in addition to Dolby B, or C, or S, or whatever. The HX designation means nothing to your playback settings, but it does indicate that HX was, hopefully, used making the tape, and hopefully that tape is a little better for that. If your old tapes say only "Dolby System", that's a Dolby B, because that's all there was at first and those are old tapes from that time.

    With the age of the tapes, play them back however they sound best to you, with whatever Dolby switch setting on your deck sounds best to you for that specific tape.

    You can't use metal tapes unless you have a specific setting, usually #4, for metal tapes. Don't bother trying metal tapes otherwise, it just won't work.

    For your recordings, if you have good blanks like Maxell UDXL, I or II, or Is or IIs, do not be afraid to record above 0 db on the meters. Experiment and see how high a level you can record on those before they distort. The higher level you can record, the lower the noise will be on playback. The higher level you can record, the less important, much less important, Dolby B is (or C or S too).

    Your #3 setting is for Ferrochrome tapes. Those were always problematic. Just avoid them. Later decks even dropped the #3 setting but did include #4 for metal, which also was problematic. You can get fine recordings on good tape with #1 and #2 tape when set correctly.
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  9. colby2415

    colby2415 Forum Resident Thread Starter

    Thanks for the information, that manual must have the info. I will first contact my repair man to see if he did it already. And regarding the meters, yeah that was one of the reasons I got it. I have a semi vintage 70s-80s setup going and it fits in perfectly!
  10. anorak2

    anorak2 Forum Resident

    Berlin, Germany
    When in just says "Dolby" that means Dolby B. You play them back with the Dolby B button on. Everything that doesn's say "Dolby" or "Dolby B" you set it to off.

    Dolby HX is different, it's a system that is active during recording only. For playback you do nothing, the Dolby B button should be off as well.

    This is true.

    No, you can use metal tapes only with machines that have a type 4 setting. That didn't even exist in the 1970s.

    Type 2, i.e. chromium dioxide. Type 3 was short lived for a few years in the mid-70s only, you wont find any type 3 blanks today.
  11. EddieVanHalen

    EddieVanHalen Well-Known Member

    Why are, in your opinion, metal tapes problematic? I used That's metal tapes for general purpose recording in the 80's and the expensive TDK MA-R and they sounded amazing. I taped for a friend the soundtrack from Jurassic Park on my Sony deck using Dolby S and HX-Pro (HX stands for Headroom Extension and was originally developed by Bang&Oluffsen who sold it to Dolby) on a TDK MA-R tape and both CD and tape were indistinguisable.
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  12. c-eling

    c-eling Forum Resident

    XDR (audio) - Wikipedia
    Capitol XDR Cassettes
    Probably some marketing and a hint of possible +'s.
  13. JohnO

    JohnO Forum Resident

    Washington, DC
    That's great that they worked for you. You needed a good deck that could handle them, not an entry level deck even if it had a Type 4 setting, and you knew how to use them. And they were darned expensive, and much more so now. The "problematic" was a metal tape on an entry level deck just wasn't worth it, such a deck didn't have the power or circuitry to handle metal to its full advantage, and there was no benefit. On a good deck it could be worth the difference in price. But they put a Type IV setting on entry level decks to look good and current.
    Our op in this thread is getting started with cassette, metal is a hassle he does not need now, and his deck has no setting for them anyway. He will do fine with his tuned up machine and I or II tapes.
    Last edited: Jul 13, 2017
  14. EddieVanHalen

    EddieVanHalen Well-Known Member

    For me Type II Chrome tapes were great value, sound was excellent and price wasn't much higher than Type I tapes. Keep this in mind, in 1992 Philips launched its Digital Compact Cassette that resorting to lossy data compression (but got very good quality, and I really mean it) recorded 9 tracks on each side of a conventional tape. DCC tapes looked more like a caddy than a cassette. What kind of tape formulation did they use to record all those 18 tracks on a regular tape? Chrome tapes. It may be the chrome tape formulation, the error correction used or a mix of the two, buy I NEVER heard a digital glitch on my four years with DCC. I had one deck and a Walkman-like (and size and weight) recorder, so I took my tapes to the street, trips, whenever. Never heard a digital glitch due to tape drop-outs or demagnetizing. There was a time on the second half of the 80's when Type II Chrome tapes were king.
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  15. qwerty

    qwerty A resident of the SH Forums.

    Hmm, I'm wondering if you understand how Dolby works. This comment, and some of the above replies, depend on the context. I will try to explain.

    The Compact Cassette was first developed as a dictation tape, so no consideration was given to fidelity. It recorded/played back spoken word with reasonable clarity for typists. The convenience of the tapes (in comparison to reel-reel tapes) promoted the use of the cassette as a low-fi portable music (take it to your beach party!). Plugging it into your hifi revealed limitations - low fi audio, with lots of hiss because of the low tape quality, narrow tape width (esp. when stereo tapes were introduced) and very slow speed. Manufacturers started to address this with better quality (low noise) tape and better electronics. But there was still lots of hiss.

    Dolby labs successfully addressed the hiss problem with their consumer "Dolby B" system, which turned the cassette into a hifi medium for the masses. Revolutionized the market. It is designed as a record-playback system. How it works is that during recording it increases the hi-frequencies, so they are recorded "louder". On playback, the equalisation is reversed, so the high-frequencies are played quieter, at the same level as they originally were. However, the high-frequency hiss is also played back quieter, making the cassette comparatively "hiss-free" compared to non-Dolby recordings. It was like magic when it was first released.

    This is why if you play a (good-quality) Dolby-recorded tape without Dolby switched in, it will sound very bright and not like the original recording. Play a non-Dolby recorded tape with Dolby in, and as you put it, it will "chop the top-end off". That's not the fault of the system, it's a user-error. In this case the Dolby circuit is deliberately reducing the high-end without an exaggerated high been recorded onto the tape.

    Many pre-recorded tapes were recorded at high-speed on very poor-quality tape (worse than the blank tapes consumers bought), which is why they sound muffled and dull, and aged and abused poor-quality pre-recorded tapes sound even worse (and tape is a fragile medium; heat, dirt, magnetic fields (eg. from an old-style TV or speakers), magnetized playback heads, etc. can partially erase the tape). Which is also why some may say that per-recorded Dolby tapes sound better played with the Dolby off - it's restoring high-frequencies which have been lost on a poor-quality tape - but this is about restoring damage, not about fidelity of playback. Playing good-quality/well-recorded Dolby tapes without Dolby does not give better fidelity - it will sound brighter, but too bright compared to the original record.

    Take a good quality cassette deck, with clean heads, demagnetised heads, aligned correctly, etc. Put a good quality tape (and the quality of both the low-noise a chrome tapes improved over the years). Record carefully with Dolby, not over-saturating the tape by recording above 0 VU on the meters (cassette tape does not have much headroom and will distort if over-recorded). Playback quality should be very good on a good-quality system. I've heard recordings played back on a very high-quality hifi which are hard to differentiate from the original record.

    Dolby does have it's critics, because it's not perfect. It boosts frequencies and then tries to reduce them by the exact same amount, which will bring in some error. By boosting frequencies you are also knocking on the limits of the tape, and you are reliant on the tape recording the signal accurately. So some people don't like the artifacts Dolby brings, and prefer to record/playback without Dolby and gain some greater fidelity with greater hiss. It's personal preference, but most with a Dolby cassette deck prefer to use the Dolby. Feel free to experiment to determine your preference.

    All this needs Dolby discussion to be taken into account in the context of the day. People loved the convenience of cassette tapes - they were easy to use, portable, can be used in car players, etc. - especially compared to the comparatively cumbersome reel-reel tapes which could provide excellent fidelity. But as mp3 reminded us, convenience wins over fidelity. Dolby B was a solution to a problem, and brought the humble cassette to become a genuine hifi medium, which sounded great on the systems 99.9% of people owned. It is why so many cassettes were sold. Not bad for something designed as a non-musical dictation device.
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  16. Solitaire1

    Solitaire1 Carpenters Fan

    I have a DCC deck and portable too. The only issue I had with them involved the electronic marks (such as Skip and Next Track) put on the tape. Once I was playing a tape and suddenly the song stopped playing and then the player fast forwarded to the next song on its own. I realized that I had put a Skip Mark on the previous recording on the tape, and when I reused the tape the Skip Mark must not have been fully erased. My solution was to bulk erase a tape (to completely wipe the tape) before reusing the tape. I agree that DCC was a good format, but I think it had the misfortune of being introduced at the wrong time.
    EddieVanHalen likes this.
  17. TarnishedEars

    TarnishedEars Forum Resident

    Seattle, WA
    I would not listen to this advice were I you. It is way easier to screw-up your azimuth than it is to get it right. And that screw on most machines was never meant to be tweaked constantly like this guy is recommending. Your head alignment was designed to be set by a technician, with test equipment, and forgotten.

    Worse, since you probably have a two head machine, or a sandwiched three head machine at best, you will necessarily be screwing-up your record azimuth at the same time that you tweak your playback azimuth.

    If you want adjustable azimuth, then buy yourself one of the three Nacs which actually had this feature. Bad advice given on the internet along the lines of messing with your azimuth (especially without test equipment) when you don't know what you are doing is the sort of activity which has ruined many previously great machines.
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  18. EddieVanHalen

    EddieVanHalen Well-Known Member

    DCC sounded great but had one huge drawback: its inability to record a TOC all over the tape. Let's get this explained well. On a prerecorded DCC there was a TOC at the beginning of the tape but also this TOC was repeated all around the tape on track 9 (the control track), so, if you were, as an example, on side 1, track 7 and you wanted to skip to track 10, the DCC deck new that track 10 was on side 2 so it autoreversed the head and motor and started to read side 2 looking for track 10. With a home-made recorded DCC TOC was at the beginning of the tape so, using the same example as before, if you were on side 1, track 7, first, you couldn't just press the "1" and "0" buttons for skipping, you had to push skip three times, then the tape fastforwarded till the end of side 1 as track 10, the one we were looking for was not on it, reversed and started fastforwarding on side 2 till it found out. Being on track 7 maybe track 10 was just a few centimeters of it but on the other side, but without a repeating TOC all around the tape there was no way for the deck to know where was track 10 exactely located, so it relied on track marks. Another drawback, that was to be expected from digital technology of the time, no buffer memory for autoreverse. If one track got split between two sides, while the head reversed and driving motor reversed, there was no sound, just a silent gap while the deck was changing sides. A buffer memory could have solved that.
  19. colby2415

    colby2415 Forum Resident Thread Starter

    Thanks, I don't think I am going to end up doing this anyways because of what you said and the fact that it sounds fine to me as-is. My repair technician did a week of testing on it, and hopefully would have had the knowledge to correct any azimuth issues, so I am confident to leave it as is.
  20. Solitaire1

    Solitaire1 Carpenters Fan

    I didn't have an issue with the time it takes to go from one track to another or the gaps in sound during playback. At least it could go accurately from one track to another unlike the method used by the Compact Cassette (searching for gaps between the songs). Skip marks were very useful to automatically skip past things you didn't want to hear (like commercials when recording off of the radio).

    I agree about the buffer memory being an issue with the portable player. Shaking the player would cause the music to pause. Unfortunately, due to it using tape I don't know if a memory buffer would have been practical, although I suppose it could load two songs in memory by playing the tape at a faster speed (the next projected song loads into the memory while the current one plays out of the memory).
    EddieVanHalen likes this.
  21. EddieVanHalen

    EddieVanHalen Well-Known Member

    Regarding the memory buffer what I meant is if you made a home recording on a DCC tape and one song got split between to sides, part of the song on side 1 and the rest of the song on side 2, there was no memory buffer to avoid sound to cut as heads and motors reversed for reading side 2. When making home recorded DCC's I kept track of time for each side. I had a Denon CD player at the time that let me make a playlist for the inserted CD, and the player told me how long this playlist lasted in minutes and seconds, that help me record DCC's without sound gaps in one song due to get it split in two sides.
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  22. 56GoldTop

    56GoldTop Unapologetic Music Ho

    And, that is why 80% (if not more) of pre-recorded tapes and home recordings made on other decks will never sound optimal on another deck, period. That screw which does not need to be tweaked constantly but only once a tape side is not made of cheese. Slightly turning it with care will not suddenly collapse the deck into a pile of metal shards, unless maybe you're an extremist. Set it and forget it will only ever work if you record your own tapes and play them back on that same machine. At the very least, you will have to set up every deck you own exactly the same; a painstaking task, not impossible but also not likely for a number of reasons. That still leaves you dead in the water when it comes to pre-recorded cassettes. If you're only ever going to play tapes you record on that deck, sure, no reason to bother if your deck has been setup correctly.

    That's a given. However, that's why I strongly recommended having a point of reference... ...if the deck will also be used for recording. Turning a screw will not reset a properly adjusted circuit, will not turn PCB pots for bias consumption levels, nor will it change the values of passive components. If the deck will be a playback only deck, a return point doesn't much matter considering the wide diversity of decks and duplicators used to produce pre-recorded cassettes. It won't matter if you're attempting to playback tapes your brother made, your sister made or dear old mum made, all on different decks. That's the whole entire point of auto-azimuth decks and decks with manual PB head azimuth adjustment.

    PB head azimuth (that does not match the record head azimuth) is not equivalent to a ruined machine. Where do people get stuff like that? But, if you want to scare someone out of getting the most from their media and deck, so be it. To which, if you know another way of getting the most out of any cassette recording without dropping a $$$grand$$$, usually more, on a Dragon, CR-7a gone over by Willie Herman or ESL, a 3014a or an actually working MAAC Marantz deck, I would love to hear it.

    If it's that much of a concern... ...get two decks; one for record and playback and another to adjust as needed to get the best out of whatever cassette you feed it (archiving). Or, I suppose one can set it and forget it and continue to be underwhelmed, believing that Dobly NR was a conspiracy and all pre-recoreded tapes sound like muffled garbage. Life is, after all, all about personal choice. :rolleyes:
  23. Grant

    Grant A Musical Free-Spirit


    OK, old-school taper here:

    1) Play them with the Dolby on, and compensate for any percieved frequency loss with the tone controls on your amp or an EQ. You should ensure that the deck's heads are properly aligned so this isn't a problem.

    2) It is your choice whether or not to use Dolby, but a good deck with a good quality tape should not chop off the highs. If it does, something is wrong. If you plan to play all of your recorded tapes on this one deck, use the Dolby. If you plan on using other players, don't use the Dolby for compatability.

    3) If you do not have a selector for type IV or metal tapes, you cannot use metal tapes. Type III hasn't been made since the mid-80s. If was a Ferre-Chrome formulation that did not win favorites. I didn't like them, either. So, today, what you will most commonly run into are Ferric Oxide (Type I 120 microsecond) and Cr-O2/Hi-Bias II type (70 microsecond) tapes. The type II tapes will generally be less hissy.
  24. GyroSE

    GyroSE Forum Resident

    Interesting tread. I've a Pioneer CT-959 cassette deck, I bought it new way back in 1990-91 and have had it since. I rarely use it nowadays but sometimes it's very nice to listen to some old mix cassette that was recorded way back in time. I'm primarily a vinyl buff but I must say that a high quality cassette deck in good running condition can sound really great.

    By the way. A while ago I did find 4 still sealed boxes of early 90's Sony UX Pro60c cassettes, I got them all for $12. The boxes are still sealed and I haven't had the chance to try any of these cassettes yet. Is this cassette considered to be a good one? I did never use this type of cassettes back in the day so I don't know anything about them.
    Shak Cohen likes this.
  25. JohnO

    JohnO Forum Resident

    Washington, DC
    If those are the Type II ones, they were considered among the best ever, short of good metal tape. Good score!
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