What it takes to restore a good Tape Deck. Final testing of a Nakamichi 680ZX

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[@kenschwarz8057]

This is my favorite Nak. All business, no glitz, great features.

[@emtube9298]

Another interesting feature of the 680ZX is Random Access Music Memory (RAMM), which is activated by pressing fast forward or rewind, then immediately pressing pause (which slows down the speed of the tape and moves the playback head a bit closer without contact to the tape), then press pause again to cause RAMM to be displayed, with the result that the tape will stop when the first extended silent place is reached (i.e., with the assumption that it is the gap between recorded audio tracks). Multiple tracks can be skipped by conttinuing to press the pause button as many times as you want to skip tracks.

[@nextsegment78]

A weird way to skip tracks. Most decks allow you to skip tracks during playback by pressing multiple times FF or REWIND. Many top range decks had dedicated skip keys in the 90s

[@fflynnful]

The 1510 came out in mid 1980s, rather than in the 1970s. I worked for an in shell duplicator. We bought one in 1985.

[@fflynnful]

Thanks for the LX-5. Nice machine and it came together nicely after refurbishing.

[@SkyFiAudio]

Glad you like it and were able to restore it, thanks so much for the update!

[@edwinsim7206]

My favorite Nak deck (I owned 2 for dubbing purposes). However, both the meters seem to have intermittent problems. They go on/off as they please. Many of the vintage decks appear to be quite involved to service (belts are hard to get to etc). Nak decks were simply superb when it comes to state-of-the-art decks then.

[@fflynnful]

The 680ZX also does half speed. It is surprising how good it sounds at 15/16 IPS. I have a 1510A Sound Tech, and it can sweep out to 15kHz at -20db on this deck.

[@sinclairforrest2178]

I have a 680 and I agree with you about the quality at half speed: awesome!

[@emtube9298]

@@sinclairforrest2178 Me, too! But for some reason, now turning the knob switch to half speed doesn't change anything, so I can't play back any of my old half-speed tapes....bummer! Not sure if it is an internal mechanical problem or a circuitry problem... Any ideas, anyone?

[@HK.Paul.]

I had one since 1986 and had the UV display issues and I Felt regret now as I think it could be repaired. I have CR40, two Dragon, one LX5 and one 1000ZXL. best sound is from 1000

[@MLX1401]

What a nice lab setup =) I really do like the Sound Tec 1510A, very sophisticated machine with a nice crt display...never seen anything similar before, just regular wow&flutter meters!

[@svenschwingel8632]

It sounds like the calibration tone is 400Hz which would indicate it's used for calibration of tape sensitivity at Dolby level (400Hz @ 200 nWb/m). The calibration showed the left channel down by ~ 1dB and the test unit reflected that in the frequency sweep. Nice.

[@alejandrocervantes4981]

Excelent video. How does this one compare ta Nakamichi 680 non ZX? Which one is more desirable and why?

[@rafacq]

Great review! Wish I could afford a Dragon!

[@emtube9298]

I am an original owner of a 680ZX, which I was unable to use for quite a long time due to moving, etc., and recently had it gone over by a Nakamichi engineer. Unfortunately, he apparently did not check the half-speed function (he rushed the work as a favor), and that is where my problem lies. The full speed settings all function well, but when the tape speed button is switched to the half-speed setting, nothing changes. The full speed indicator light remains lit, and the tape speed etc remains unchanged. If anyone has any useful information or experience with such an issue, please respond to this comment!! Many thanks!!

[@general682002]

One of the many common build for commercial use!

[@8BitNaptime]

Can you record with Dolby at half speed since the frequencies would be offset?

[@LetThereBeSound1]

You misspoke @ 13:05. A 10.5" reel loaded with typical 1mil thick tape, running 15ips, would provide the user with about 33 minutes running time. 7 1/2ips is the speed that would give about an hour or an hour six minutes (+/-) to be exact.

[@ju6452]

Hi, the meters on my 680 only work from time to time. Do you have an idea what could be the fault? Thnx from Frankfurt

[@ingenfestbrems]

Isn’t wired remote controls basically switches? Or do they send a specific signal?

[@simplifygoals]

Where are you from?? I have a CR7 and I want to restore it, auto calibration not working, playback seems perfect.

[@AudioGuyBrian]

I love Nak gear and own a couple myself, but the goofy need to use little screwdrivers to make fine adjustments to BIAS for each tape type instead of just having knobs there is beyond belief.

[@syhi7971]

Id love to work at your shop :) Just serviced a TA2070. Full recap and everything. If you like messed up wiring its the right unit :D. Id learn so much....

[@umeshupadhyay...]

I am having Nakamichi ZX7.Very recently a new issue has cropped up of the standby light of stop button continuously flickers and therefore nothing can br operated .It is also a fact thst in India dust particles peneyratr through various openings.Ciuld yiu please guide in the matter.

[@sunsan997]

Excuse me, but please tell me. Is the 680ZX Bias adjustable?

[@mrk131324]

By selecting the tape type. The actual bias is preselected for Nakamichi tapes, but can be adjusted by a technician. The little adjustment screws underneath the VU meter are not for the bias as stated in the video, but for the record level for the noise reduction reference tone. I own one of these machines. They are fantastic and bias was never an issue unless you want to record on real CrO2 tapes (e.g. BASF, AGFA).

[@opnarth]

Not really. You'd have to take the cover off to adjust the bias. They are set up for Nakamichi (really TDK, I think) tapes from the factory, but you can have technician set the bias for any tape you want, but then you should really stick with that tape for recording.

[@Duc_hunter]

I wonder if it’s any different from just 680

[@MixiMera]

Really sophisticated audio / electronics lab in your home. I got the Nakamichi 680ZX but it is beginning to give up. Who is really buying cassette decks these days? Vinyl record players I can understand but decks…?? I am glad I listened to your dedication.

[@young_of_the_mill9560]

I record my vinyl on type 2 and play back on this deck

[@miamichi5]

Hello great video 👌. ? I just bought a denon tape cassette player recorder. ? If I have any issues in the future can you service it. I'm in Florida. Or do you know of a repair shop in Miami? Thank you. 👍

[@Eyerex]

I've never seen a Dragon let alone hear one and you have half a dozen sitting in the corner "it's not fair"

[@RUfromthe40s]

you´ll be disapointed

[@Eyerex]

@@RUfromthe40s Never, i've dreamed about owning a Dragon from when i was little sitting in front of a Realistic SCT-29 making tapes and one day if i come across one and have a chance to hear her that day will be a good day

[@RUfromthe40s]

@@Eyerex i completelly understand i also have a similar situation ,i´m looking for a car that would cost a lot of money but it also drinks a lot and with the price of gasoline being maybe the xpensier in all Europe i´m doing it anyway, i´m talking about a 73 merc with a V8 engine and i drive daily a ford fiesta diesel from 94 (to save money)comercial version ,only two seats, regards and health

[@mikep9234]

Your not missing anything. Honestly cassettes are noisy, have low band width and break easily. They are about the same quality as a good mp3 file.

[@Eyerex]

@@mikep9234 From making tapes as a kid from my records to the present day making tapes from music download from Bandcamp i still enjoy making and listening to tapes

[@morrisonAV]

I have a 670ZX and was wondering what the difference was between this unit and mine?

[@opnarth]

I have both. Both great machines. 680zx has slightly better specs, slightly richer bass, 2 speeds, fluorescent meters. The electronic meters are very nice on an old deck, since the physical ones sometimes get sticky in their old age.

[@leo.girardi]

Dragon was introduced the same year.

[@PedjoGT]

Great camera work😅

[@paddle_shift]

I had one of those. Damn, i regret getting studied into the CD realm. Wish i still had it! Wish i could have watched this completely, but the videos excessive movement gave me motion sickness.

[@young_of_the_mill9560]

How do you fine tune the bias on the 680zx?

[@Giblet535]

Parts. I need Dragon heads, a 680ZX VFD, and idlers for both. How much?

[@SkyFiAudio]

Sorry we're not a repair shop and don't offer parts. Best to check eBay/setup a saved eBay search to snag them when they eventually pop-up for sale. Good luck.

[@EmilioGarcia-fr5po]

Really cool.

[@Stelios.Posantzis]

11:05 Since this has a handle on the side, you may be able to squeeze a metal stop between the handle and the frame that would prevent the lever from being pressed too far. A bit elaborate though. 12:28 That would be an awesome feature for transcribing 78rpm shellac records at have speed (if you have a turntable that can do that, i.e. 39 rpm - maybe a Technics SL1200? I guess not since it's +20% for 33.3rpm and -13% for 45rpm) and thus help preserve the shellac and get a better frequency extension and dynamics with less noise? Hmmm... that would require a totally different equalization pre-amplifier though...

[@emtube9298]

Not sure it would help with transcribing the 78rpm records, because the tape bias etc settings are separate for half- and full- speed, so playing a half-speed recording at full speed results in mismatched bias etc., particularly messy for the noise reduction. Also, I guess a turntable capable of playing at 78rpm would be cheaper than trying to buy a working 680ZX deck...

[@Stelios.Posantzis]

@@emtube9298 A-ha! That is very useful to know! So no matter which bias setting you choose, if you record at a slower speed that the reproduction speed, you will always get a sub-optimal result? Maybe there is a range of speeds where the bias settings could be relatively constant but then I guess this would not translate into a significant reduction of 78rpm record speed. The problem with 78rpm records is two-fold (actually many-fold but let's keep it simple): a) record wear, even with just a one time playback if using the wrong kind of needle/stylus b) needle/stylus wear Modern turntables are not equipped to play old 78rpm records, and by 78rpm records I mean those made of shellac As such, playback with these turntables will end up ruining the record, even if using the correct stylus and tip (which cost money, good ones being quite expensive or really expensive). If the record is already ruined before playback, additional playbacks will eventually result into making it unplayable. If the right stylus tip is use, e.g. made of sapphire, then the stylus wear comes into question as a sapphire tip will only last 2-3 record playbacks and I don't even know where one can get such tips. It quickly becomes uneconomical. The correct reproduction of shellacs involves using thorn or wood (shaped like a thorn) needles and the like. It's the only economical method of replay but that means using a gramophone. Gramophones with an electric cartridge/head that allows replacing the needle are extremely rare but you never know. The other option is a laser turntable such as ELP. I'm not sure whether ELP can reproduce 78rpm records though. Even then, the surface noise when replayed through a laser turntable (there is no mechanical filtering or debris cleaning such as that accomplished by a needle/cartridge) is intolerable.

[@emtube9298]

@@Stelios.Posantzis I see that you are very well-versed in this matter. I just found an interesting presentation on KZbin that presents 4 different configurations for playing back an old "short-play" record (78 rpm, or 80 or whatever). kzbin.info/www/bejne/nKjdpJSIrNGnhbc The presenter uses a typical suitcase player, then a good (modern) turntable with a typical microgroove needle, then replaces the needle with a 3mm Ortofon mono needle (sounds gooooood!), and finally on a vintage acoustic player with a steel needle (not bad!).

[@Stelios.Posantzis]

@@emtube9298 Thanks for the video link. It's an all-rounder video and has good basic guidance on setting up a cartridge - showcasing some useful tools. The first and second replay is how you get a 78rpm record damaged fast. The third is how a slightly damaged (worn) and dirty 78rpm record sounds like (which is the case for most 78rpm records inherited and found in the attic/basement). The last replay makes it obvious how proper playback minimizes surface noise. You don't get the bass of course which is in large part due to the mouth of the horn being undersized (you need a horn with a mouth about 2.5m wide and length about the same or more to get some bass). You cannot avoid surface noise totally of course but the cartridge (i.e. needle, diaphragm etc.) can only respond only up to a certain frequency because of its large mass. I'm not really well versed in this 78rpm matter. It's just information that is (or was - you never know) on youtube regarding vintage gramophones/phonographs. If you spend more than a few minutes searching you're bound to hit the videos addressed to those wanting to know more about this old technology and some are made by true aficionados. I don't mean the videos about just "how do I play a 78rmp record?" of course. There you'll hear about comparisons between cactus thorns and bamboo or "fibre" needles and the like. See here for example: kzbin.info/www/bejne/h4G2imWQqq5mZqs If you check these out you'll immediately realise that collecting and replaying 78rpm records is a very, very esoteric and expensive sport - not unlike collecting vintage sports cars. It requires a lot of space, time and money and good connections in order to build a collection. That doesn't mean you cannot do it on the cheap of course, provided you have some space to store a few records. Unfortunately, when such people die, if they have not made arrangements, sometimes an entire collection can end up in the skip or sold off on ebay bit by bit. Most 78rpm are sold online by people that do not know how to package them and that means they are broken and then tossed away. But most 78rpms die when someone decides to do house clearing. These are usually well worn off - not unlike the ones you find in antique fairs and second hand shops. Shellac records are particularly sensitive to storage conditions and can grow mold etc.

[@JMAudioEditions]

change the frame rate to cycle in incrments of 30 60 or 120 and you will get no flicker- 120 in USA - 25, 50 and 100 in europe to match electric grid -JOHN M @ JM AUDIO EDITIONS

[@mannybarbosa9312]

Hi, would you take my cr7 in for service

[@tarunsangeet6816]

Hey guys at SkyFi Audio Any chance of my buying a restored/refurbished Nakamichi CR 7 of off you?

[@SkyFiAudio]

Of course, please visit the listing for the CR-7a on our site for more details.

[@tarunsangeet6816]

@@SkyFiAudio I did. I noticed that you ship only to Canada and continental US. I’m in India. 😢😢

[@kravchuk007]

Excellent

[@spedslojp3353]

anyone know where to buy 1 or 2 of the switches/buttons?

[@SkyFiAudio]

ebay is your best bet,.

[@PaulJCost1]

Subscribed!!

[@young_of_the_mill9560]

How much for that Nak T-100?

[@SkyFiAudio]

its the only one I got :-(.

[@PedjoGT]

Do not have manual azimuth

[@marcviej.5635]

3:25 ''very basic stereo receiver'' lol at a 2k amplifier

[@gixxerboy555]

Nice but isn't this overkill?

[@SkyFiAudio]

Not from the feedback we've received so far. Analog folks are serious.

[@davidedutremblay5050]

I’m enjoying your videos but not enough to subscribe

[@danielmarshall4587]

.....LINN Speakers , "your 'avin a laugh".

[@blackimp4987]

no bias regulation? pity

[@danielesbordone1871]

I remember Nakamichi was way out of reach at the time , similar to Revox.

[@RUfromthe40s]

yes ,similar,because the revox does work

[@RUfromthe40s]

the b215

[@koosvanleeuwen6340]

Piraten muziek????

[@krunofilipovic7213]

If you allow for some humor, a garbage bin?