OT - calling all hipsters - C90 cassette - HK2000

[RJH]

Never tried it but on the couple I've replaced belts, the amount of work that went in made the fiver or so seem worthwhile.

[tabbypurr]

it was primarily the time that pushed me into trying it. I could fix the thing right now and be all done in 10 minutes. The fiver is a little bonus.

Whether most bands still last well today I don't know, I know the PO ones don't.

NT

[michael adams]

One minute its autoazimuths, and the next minute its cheap stationary rubber bands.

Does the one compensate for the other, then ?

Poundland meets Russ Andrews !

michael adams

...

[Ian Jackson]

In message , michael adams writes

Maybe he could start a chain of shops, called One Hundred Pound Land?

[Tim Streater]

What is a "spade neck beard"?

and WTF is a "hipster"?

[David]

And furthermore, WTF is Google?

And get off my danged lawn!!!

Bloody kids.

[The Natural Philosopher]

[Tim Streater]

Ah, they're twerps. I thought they probably would be.

[Johnny B Good]

It's a pretty safe bet that that will be the case if my Aiwa 3600 twin capstan drive unit is anything to go by. :-(

Reading this post gave me the urge to satisfy curiosity and dig my own Aiwa deck out of the cupboard to give it a quick check over. Sadly, it turns out that the capstan drive belt, along with the counter/motion detect drive belt have both snapped.

Initially, I couldn't even get it to fast wind in spite of the FF and REW modes using a seperate motor/idler wheel drive system (which also acts to provide the take up function via a slipping clutch which slips a bit too much when it comes to fast winding - a minor irritation before the belts melted into gloopy ghosts of their former selves).

I removed the cover to take a look at the mechanics of the deck and, just as I discovered with my ancient Philips data cassette drive units about ten years or so back (maybe even longer), the "rubber" drive belts had decomposed into a horribly sticky gloop that's extremely difficult to remove from surfaces, including skin if you make the mistake of trying to grab "the broken ends" of what, at first sight, appears to be merely a belt that snapped.

I dare say that replacement belts shouldn't be too difficult to source, especially when you can substitute a square section belt running in V grooved pulleys with a round section one. A flat dual capstan drive belt, otoh, may prove a more problematical item to source a replacement for. However, fitting the replacement belts (once you've acquired replacements) is the easy part of the job. The hard part will be the removal of the gloopy remains of the decomposed belts, a task not to be dismissed lightly.

When you come to open that F770 up, resist temptation to dive straight in to remove the rotted belts without an array of tweezers and cotton bud sticks to wrangle as much of "the merely snapped ends" of the belts without causing too much contamination of the drive mechanism and fingers. The gloopy mess that remains is severely sticky; a sort of cross between freshly squeezed Evo-stick and warm bitumen.

As for that 3600 of mine, I'm not even going to look for spares. I've reassembled it and put it back in the cupboard. I don't have any cassette tapes that weren't dubbed from R2R in the first place and, afaicr, I've already digitised the few recordings that existed only on cassette by the time I came to digitise them. Sadly, I don't see much point in fixing it up.

[RJH]

Yes - there seem to be a few suppliers on ebay that have taken the trouble to source the spec of a large number of decks and sell drive bands that should fit. For a price, of course!

The hard part will be the

I don't mind that part - it's the disassembly that I find tricky. I did a Technics top of range a while back, and that took some hours. And I have a Sony three head deck here waiting to be done - the pretty good manual and online tutorials seem to suggest something similar, with some circlips (not sure my pliers will fit something so small, wait and see).

My other cassette deck - a Denon mid-range direct drive - does still work very well indeed. I've had it 20 years, so there's a moral there somewhere. I'd loosely assume there are no belts at all - but I've not taken the trouble to check.

All of that said, I rarely use it - maybe every couple of months and an old Peel Festive 50. happy days :-)

[Johnny B Good]

I usually see if I can cheat a little by just slackening off bearing mounts to create the necessary gap to slip the new belt into the works. Not always possible but worth a try.

There may be a small belt to drive the counter which may also be the method to drive a motion/end of tape detector as is the case with that

3600 deck.

Apropos of direct drive, I have a couple of Akai R2R decks, a GX630DB and a GX747, both direct drive models. However, both rely on a small drive belt for their tape counters.

The earlier GX630DB uses a simple 4 digit odometer driven from one of the reel table hubs to provide some sort of indication of where to wind to to get near to the start of a desired track. All things considered, it doesn't do too bad a job usually being within a couple of percent of the originally noted counts.

The newer GX747 otoh, egregiously resorts to the totally pointless use of a drive belt to transfer the motion from one of the two anti-flutter wheels (it's a 6 head bi-directional auto-reversing deck) to a seperate shaft which drives an optical sensing wheel which generates counting pulses and a signal to indicate direction which drives an electronic counter calibrated in hours minutes and seconds (possibly switchable to indicate metres or feet - it's been a good 25 years since I last packed it away into its box).

The egregious part of this is that the optical disk sensor could so easily have been mounted directly onto the anti-flutter roller spindle in place of the pulley which would have not only saved the needless cost of a second pulley and a rubber band but would also have eliminated the extra drag and tape to roller slippage on top of the additional slippage in the rubber band drive itself.

Ghod alone knows why Akai decided to splurge additional *dollars* on unnecessary and counter-productive components when previously they had done a similar dis-service to the GX630DB's Dolby NR boards where, for the sake of *a few cent's worth* of two resistors and a capacitor per channel (2 encoder and 2 decoder circuits), they totally destroyed the record and replay amplification chain's maximum headroom to the point that the replay clipped at a mere +8dB, clipping pre-recorded High output tapes with +12 to +15 dB levels and (unnoticed by the reviewer who had picked up on the replay issue) likewise clipped bass content going through the recording amp.

Thankfully, I was able to spot Akai's skoolboy howler when I examined the circuit diagrams in the service manual I had ordered straight after purchasing the deck. It was a most satisfying moment in my life to discover about a year later when I read a Wireless World article on building Dolby noise reduction boards that the extra components I'd added to correct the mis-biassing of the emitter follower output stage made the circuit match the official Dolby NR circuit exactly! :-)

Since this emitter follower stage directly drove the line output, I beefed up its negative pull down drive capability by replacing the simple emitter resistor with a constant current source so as to stave off asymmetric clipping into the typical 10K minimum line input loads taking the minimum load impedance down to 3k3 ohms before the risk of asymmetric clipping could once more arise.

I didn't need to do this with the encoder boards which sat between the bass boost EQ and HF boost EQ sections of the recording amp since the emitter follower was driving a fixed Hi-Z input stage. These modifications to the Dolby replay decoder took the replay clipping level to +18dB, nicely in excess of all but the most horrendously over-driven into saturation recordings on high output tapes. IOW, I'd be suffering gross tape distortion long before replay amp clipping distortion would start creeping into the picture - just as it should be with *any* analogue tape replay system no matter how humble its specification.

I can only conclude that the bean counters at Akai inc must have literally put a gun to the head of the chief designer to force that performance destroying penny pinching on what was an otherwise state of the art example of analogue magnetic recording technology.

Anyway, those criticisms aside, the possible issue of drive belt rot with the GX630DB isn't really a biggie since it only effects a primitive tape counter whose function can be replaced by the markings on many of the plastic reels for this purpose where, in any case, the MK 1 eyeball can effectively gauge the situation even without such reel markings.

The GX747 otoh is a different kettle of fish since, at the very least you lose a moderately accurate (to within a few seconds end to end of a 3

1/2 hour tape but which could be so much better again) tape position indicator which can be preset to a value other than zero when the occasion demands. A failure that could so easily have been rendered impossible if Akai's designers hadn't had their collective heads so far up their feckin' collective backsides when designing this otherwise excellent deck.

In neither case is the counter used to drive a motion/stopped tape detection circuit as is typically the case with most cassette decks, relying as both do, on a seperate drop arm held up by tape tension. Indeed, the reversomatic GX747 has additional sensing contacts to detect optional end of tape foils between tape and leaders so as to effect the reversal before the tape becomes unthreaded from the reel.

I've just checked the GX630DB's tape counter (it's driven from the supply reel) and it appears to still be functioning ok. Unfortunately, in the case of the GX747, I'd have to retrieve it from the top of our fitted wardrobe, unpack it and plug it into a mains socket before I can thread a tape in order to test the counter.

Since I have no immediate plans to press the 747 back into service (it lacks any form of noise reduction circuitry which is both a good and a bad thing - bad because I'd have to buy or make up my own Dolby boards to replay my existing recordings but good because there were no Dolby boards for Akai to f*ck up in the first place), I'll leave it to fester in its original packaging for most likely forever or until I get an offer I can't refuse.

Even if the drive belt is still intact by then, I'd recommend that the new owner relocates the optical wheel directly onto the ant-flutter wheel spindle and use a Rasberry-Pi to deal with the change of pulse rate that such a mod would create (no such things as R-Pis back in the day when I first contemplated this modification shortly after its purchase). This would solve the rotted drive belt risk issue at a stroke and improve accuracy by at least an order of magnitude, particularly so in the case of fast rewinding after playing through a whole reel of tape.

I really only need to keep the GX630DB going so I can resume digitising the rest of my tape collection when I finally get another round Tuit. I might even resurrect an old skool PC with the required 16 bit ISA slot to press my rather excellent and expensive AWE 64 Gold card back into service just for this work. 16 bit 44.1KHz sample rate is way in excess of requirements for even the best of these recordings (and don't let others persuade you that it's otherwise).

TBH, a half decent USB ADC/DAC adapter should serve just as well, if not better, and the use of 48KHz sampling rate also wouldn't come amiss. It's a fairly trivial task to resample down to the 44.1KHz CD sampling rate standard if you wish to distribute anything in this legacy format so it might be a wise move. There's absolutely no benefit in digitising to

96/192KHz 24/32bit, those rates and bit depths are best left to multichannel mixing down to whatever final digital format is called for.

Expressing the dynamic range performance of tape recordings in digital terms[1] gives us 9 bits for cassette at best with 5 to 6 bits being more typical and 13 bits for best analogue R2R (with advanced noise reduction). Digitising legacy analogue collections (with perhaps the exception of DBX encoded tape and vinyl) doesn't require anything more than a half decent 16 bit soundcard to capture the recordings with ample headroom to spare.

[1] mentioned at the 11 minute mark.

[RJH]

Snip detail - you've been through the tape mill!

I'd recently bought a rack mount Marantz (PMD560, £30ish on ebay) which is great to use - meter and manual controls. But maximum 16/48 PCM recording. It was suggested on the uk.rec.audio NG that 24 bit might be better for the initial recording, then convert down to 16/44, for digitising vinyl and cassette.

I don't tend to listen that intently, or at high volumes, any more to the point that I find decent cassette recordings and vinyl generally pretty good. And, because of the nature of the recording and some other weird variables, sometimes better - especially vinyl.

I like that bloke's videos - he communicates it all well for a non-tech like me.

[The Natural Philosopher]

Well most cassette tape machines would do 40dB range at a minimum - thats 7 bits, and 50db is more usual which is around the 9 bit mark.

I forget what a top quality studio R2R on 1" tape would do, but Im guessing up around 80-90dB which is getting on for 16 bit.

That I agree with 100%.

[Johnny B Good]

There used to be a time, back in the late 70s, early 80s, when an understanding of analogue magnetic recording was worth having. With the advent of cheap digital recording kit, other than for maintaining such kit in order to digitise legacy material before the original media crumbles into dust, such knowledge becomes just a matter of mere historical academic interest.

Aside from the need to digitise an existing tape or vinyl collection, running such venerable kit, no matter how excellent it might be in its class, is really more a matter of satisfying a nostalgia trip in its most tangible form, an actual re-living of the original experience! :-)

Also, of course, there's the issue of hearing just how close to "Audio Perfection" it was possible to reach using purely analogue means before we were able to 'cheat' using digital processing to more perfectly capture the audio waveforms that comprise a musical performance.

Since the 'musical experience' of most of us "Oldies" has largely consisted of vinyl and radio broadcasts rather than live performances, it can be counterproductive to the nostalgic experience to "Clean Up" a tape dub of a borrowed album 'just because you can'. Those pops and clicks (and even bursts of white noise and distortion where the original owner may have pressed the tone arm onto the record to stop it skipping on his Dansette record player) can often become an embedded part of your original experience which, if removed, would be perceived as a 'loss of fidelity' to that experience.

The stark truth of the matter with regard to even high quality tape decks such as those Akai units, coupled with high quality Japanese manufactured R2R tapes (American and European tape manufacturers couldn't hold a candle to the likes of Maxell and TDK when it came to quality), was that it didn't make much sense to keep using them to record new material. Digital recording devices, including that vintage (12 years old for Gawd's sake! :-) ) PMD560 can more perfectly capture new audio sources so much more conveniently. Besides which, there's the cost and availability of Japanese high quality R2R tape to consider if you've consumed all your stock of unused tape as most R2R tape deck owners will have done long since by now.

Most (but not all) of the younger (20 and 30 somethings) generation of "Hi-Fi Enthusiasts" would regard my continued ownership of such 'vintage' audio kit as a pointless obsession. The few that see beyond this, are the ones that desire a better understanding of how things *actually* work.

Thankfully, there will always be a small proportion of any one generation that never lose their scientific curiosity of the world around them from the moment of their birth. We've all started off as practical scientists from birth - how else do you think we *all* learnt to integrate the stream of visual data with the stream of aural, touch, taste and smell sensations into our own personal VR suite (aka, "The Visual Cortex") which represents the working model of the world we have been born into and are obliged to interact with if we wish to survive long enough to procreate and give the next generation a chance to enjoy the same experience? :-)

The bottom line to the comments raised by the OP's original question, regarding the value or worth of a vintage "Hi-Fi Cassette Deck" (venerable or not) is that it depends on whether there are enough people with an interest in owning and using such kit to generate a demand by which to apply the "Supply and Demand" equation to. Regardless of what you, the OP or I think, there will almost certainly be some people with their own legitimate need to own and operate such kit.

Unfortunately, I'm not one of those people so can't offer a valuation suggestion. All I'd suggest is that the OP researches the market and try a 'Suck it and see' approach. Discussing the merits or otherwise of a cassette deck, quite frankly, seems to be beside the point when even the best quality R2R tape decks of the day, using high quality Japanese tapes still fall short of the "Hi-Fi Ideal".

JOOI, I googled the model number and read through a PDF of the user guide, noting a "Printed in Japan" date of 2005/12 at the bottom of the last page which suggests an approximate product age of 12 years. The use of CF cards seems anachronistic even way back then. Fortunately, even the most expensive 4GB CF card (Argos, who else?) is a mere 25 quid which will almost certainly be cheaper than a 10 inch 3600 foot reel of Maxell UD35 tape (namely, Maxell UD 35-180B). Actually, after looking on Amazon, Argos are far from being the most expensive. There's one hell of a wide variation in the price of 4GB CF cards which ranges from as little as £8.25 (Ebay) to a high of £69.99 (Amazon). Mind you, buying flash media from almost any Ebay trader is at best a risky business.

Just on a hunch, I googled "cf card to sd card adapter" and found plenty of hits so you can even avoid the CF card price premium using a cheap adapter (99p to a high of £7.35, both Ebay). That 30 quidish spend seems to have been a good investment. :-)

It's been many years since I last auditioned vinyl and R2R recordings directly other than when I was digitising them. Most of what little listening I've been doing during the past decade or so has been through my office desktop speakers, typically my own MP3 renditions of the wav files captured from the tapes and vinyl that I've processed so far.

Since the front room adjacent to the living room (I suppose what might best be described as the front parlour) has recently enjoyed a bit of a decluttering, I think it's now high time for me to commandeer it as my own personal auditorium before the missus claims it for herself.

Since she long ago claimed the living room as her personal space by instigating a radical remodelling some years ago, I stand a very good chance of setting up some sort of Hi-Fi setup where I can listen once more to my eclectic music collection on real full size speakers and in rather more comfort than an office chair. I just have to get off my backside and get it all sorted out.

Unfortunately, that means finishing off the rewiring job from several years ago where I left a small loop of 2.5mm FT&E ready for me to add an additional double socket I was planning on when I rearranged the existing downstairs ring main to add more sockets to the living room.

I just need to dig out a rectangle from the plaster to take a twin outlet backbox, chop the cable, fit said backbox and terminate the wiring onto the new socket terminals. I didn't do it at the time since it wasn't massively urgent and I'd had enough of fitting the extra sockets in the living room by then which had been the primary purpose of the rewire. At that point, with the cable already in place, it seemed like an opportune moment to take respite from the rewiring exercise. It didn't occur to me that what was expected to be just a few day's hiatus in completing the job would turn into a 2 or 3 year 'sabatical'. :-) Mind you, it did help that this loop of cable was well hidden from sight by the presence of a nice chunky leather armchair.

If I do manage to take over the front parlour, I might even have a go at refurbishing that Aiwa 3600 deck. I'm almost certain I have its service manual somewhere in the house - it was certainly of a quality sufficient to justify the expense of such a luxury so I'd be very surprised if I hadn't purchased the service manual straight after buying the deck just as I had in the case of the GX747 purchased around the same time.

His videos are such a joy to watch that I often find myself watching them in full after revisiting them just to grab a link to post in a usenet reply even though I must have seem them at least 3 or 4 times already. :-)

[tabbypurr]

I sincerely hope no-one has ever been miserable enough to try to record off a Dansette any time in the last 50 years.

NT

[Johnny B Good]

I was merely offering a likely scenario to account for the abuse meted out to a borrowed Beatles LP (Revolver, IIRC) by a previous owner. The lowest quality of record deck I ever used was a Garrard SP25 with, initially, a cheap ceramic cartridge driving the mic input on a Philips portable R2R tape recorder via 1M ohm resistors to down-mix into mono.

I think I was using a GL75 deck/arm/cart setup with an Akai 4000D by the time I was recording that Beatles Album some time around 1967.

[michael adams]

He's the kind of guy Who never used to cry The world is treating him bad, misery He's lost her now for sure After trying cheap elastic bands It's going to be a drag, misery

Lyrics courtesy, John Lennon, Paul MacCartney, and Russ Poundland.

michael adams

...

[therustyone]

I think you must be running MP3 at its default 128kbits which is why it's very rough, suitable only for audio books. 192 or 256 kbits give a marked improvement.

[therustyone]

I also recall problems with eccentric Akai circuits. A stereo/mono switch on an FM tuner that connected together the emitters of two emitter followers in the R & L channel outputs. Hate to think how that distorted the difference signal. Long tailed pair?. More interestingly, a UHF preamp where the board's earth was connected to the neutral of the mains supply. OK until the mains was wired the wrong way. Both of these were like first year student errors.

[Dave Plowman (News)]

Remember a pal buying a separates Pioneer system. Not the most expensive on the market, but not cheap either. Every single unit had the mains earth connected to chassis. I suppose to conform to UK regs. Ordinary phono connectors with screens also connected to chassis. And didn't it hum...