This from what I gather is a rather rare piece. Considering that I have been servicing audio video gear since 1984 and I have never seen one before, until now!
I've got a RS-676US that I bought in Korea in '75. Used it for many,many enjoyable years and still have it. Pulled it out of service back in the early 2000's when while recording, a channel would drop out. I still have it and glad I stumbled upon your overhaul procedure. I'm retired now and have plenty of time. I'll check out your procedure ,tear it down. Keep you posted and thanks!
Beautiful unit! Have 5 x decks awaiting restoration (including Sony TC-U2, TC-U30 and TC-FX2) and find these videos enormously helpful. What a beautiful unit. So enjoying this excellent series of videos, made by a virtuoso engineer, par excellence.
I have one that I purchased in1974 when I was in Germany in the Army. I need to replace the belts. I have never had it apart. Your video was quite helpful.
That's amazing. All that electronics for a cassette deck. They made this a good one though. Screams of quality! When that person gave you this deck, he could be rest assured it would have a good home!
What a beautiful piece of equipment. I had the big brother of those speakers Technics SB-7070...they were absolutely gigantic, and my wife hated them! They had 4 drivers arranged with "linear phase".
You sure scored they will never make equipment like this again it is really good that it went to someone who can repair and maintain it and appreciate it
Very impressive vintage cassette deck!! The engineers were really thinking when designing this piece of equipment. I like the little stand offs for the capacitors.
34:33 Yes. Everybody recorded with the Dolby on then played back with it off so we could hear the high frequencies. Nice and clear. I still feel like the sound I heard when I was listening to music with Chrome tape recorded like that and listening through a top system was better than the digital stuff we have today. I own and record live music using a full DAW studio. (Digital Audio Workstation). Meaning using a digital interface for the inputs to record onto my computer using professional software and some pro hardware for processing etc. Yet even if I have full equalization control and using Aural Exciters for high and Low frequencies etc etc. I still feel like the audio I used to get recording in the Analog Studios back in the day onto 2" Tape was superior to the absolute perfect digital I am using now. I actually use software that will ADD NOISE to the recording because it has been shown that the human ear finds that that noise is pleasing to the ear or brain or whatever it is that happens. LOL. I use a unit called the Ferric TDS which after adding it to the mix makes it sound closer to the old 2" tape I used to hear and was used in all the great albums of the past throughout the 50's, 60's 70's and some 80's even into a bit of the 90's but extremely rarely now. (Maybe Dave Grohl and a few like him).
That's an awesome peice of gear I love old school.... That reminded me of a Harmon Kardon CD-91 cassette player that was gave to me years ago it's gonna need a little work it's a project for later on when there's time. The best of the best 👍👍👍👍👍👍👍👌👌👌👌👌
Might not be a Nakamichi, but way more reliable. Nakamichi, and I know I am going to ruffle feathers may have performed well, but they were never regarded as very reliable. I fixed tons of Nak equipment. Their warehouse and parts depot for all of Canada was right here in Vancouver, and I used to order many parts from them. Main power transformers were a weakness on their amplifiers. Kid would have a party and crank it up. The transformer would warm up and blow the internal thermal fuse. Caching, that will be 300 to fix it sir, thank you very much. Couple of months later same unit back, power transformer blown again. Caching.,300.00. Customer is pissed. Response. Did I go over to your house, hold a party and crank the shit out of your amplifier and burn the power transformer out? No, well then stop bitching at me, here is Nakamichi's phone number, take it up with them! After seeing the quality of the units, I would never own one. (and yes I was an authorized Nakamichi servicer, they actually gave that out to anyone that bought parts form them. Call to buy parts, and they would say, want to service our stuff under warranty? Here fill out this application. They paid crap. Lower rates than Sony did, and Sony stuff was much easier to fix, but they did pay better than Yamaha, and some of the Yamaha stuff was brutal to work on.
great video!! :) i love the excitement you have about this unit, it shows how passionate you are about stereo repair. i share the same passion, but lack the knowledge you have. i very much enjoy hearing about the ways and reasons and how dolby/dbx/mpx filtering worked. it's that old school knowledge that i'm always after. anyways, great vid and i'm glad you found such a great tape deck. i'm jealous!!! take care, i hope you're well
Actually it is called "acting" I am not as excited as I make it appear. I do like the vintage gear for music. I have 2 systems. A home theater in the TV room, and a 2 channel full tube system in the music room.
Really nice. I had a technics system in the 90’s and I loved it. It had 10” woofers but it had better, more powerful sound than my friend’s fisher system which had 15” woofers.
I am the lucky owner of a lot of Technics gear, including the four track reel deck RS-1506 and the cassette deck RS-673. The speakers you show have been on my wish list for years, they are wonderful. Great video! (FYI, this deck, model RS-676 was sold for the first time in 1974, its weight is 20 lbs, price first year of sale: 460 USD.) Another very big name in cassette decks used to be Nakamichi. BTW, to get easy access to the heads you may remove the plastic cover on top of them.
Cold dead hands! That's when you give that one up!!! Really nice shape! Great score! Plus an education about Dolby. Thank you for that. Those solenoids! They probably do not use solenoids that big on automotive applications!
Yes this one will have to be pried away. That is unless some audiophool offers me a ridicules amount of money for it. I had a nice Sansui "direct o matic" loader and I figured I would put it up on fleabay and see what happened. Some audiophool offered me 400US for it. As much as I liked the deck, I am not dumb. Away it went.
Technics (RS) 673 was even more beautiful , same window and damped eject . This one had HPF heads which you can compare with the Ferric heads Sony used , almost indestructible . The 673 had SX heads and sold very well only 2 heads but with a lot of possibilities . It costed 1200 Dutch Gilders > 600 US Dollars , new from the store , also very heavy .. The sound is amazing even by todays standards . Sold from 1977 till 1979
I think the reason for the 19Khz MPX filter was to attenuate the FM pilot tone, so that the Dolby encoder on record would not be influenced by this 19Khz sinewave. Awesome deck, and great photography 12voltvids!
not sure how i missed this video of yours, been a fan for a few years now, I just picked up the Technics RS-631, paid around $25, £20 in the UK perfect working, sounds amazing, only draw back the tape buttons are aluminium and have some minor pitting but still a fantastic deck & they have huge belts.
Nice technical service bulletin. I'm into the same "hobby" and perform normal maintenance on my 18 or so decks. Here's a bit of trivia. The mid 70's Technics RS decks 630/ 671/673/676, and semi pro model RS 288 with the lighted horizontal tray compartments were ALL based on the TOTL full laboratory professional (2) chassis RS-9900US. I acquired one via Germany, which needed a major overhaul. It also came before the short lived metal tape revolution. However, This may sound crazy but but to my ears it easily outperforms anything built after from the late 80's and 90's. I too will never sell it...
First view AND comment. What a lucky person I am tonight. And incredible that you found what could be NOS Technics equipment. A rarity indeed, Dave. It's age is the secret of life, the universe, and everything (bet you couldn't figure out what that references).
This tape deck is probably as close to a NOS as one will ever find. It hasn't got a single scratch on it, nor does the big receiver I got at the same time.
Colton Rushton He was a one off, no one like him. Advanced beings that just happen to look like mice, on earth to study humans. That's just well outside normal writers imagination. Sorry ill shut up lol.
Love the solenoids! None of this "Let me just turn this giant brittle plastic wheel around to move some mechanics" crap but simple "You touch it, it plays".
I own the RS 671 and I love it. Heavy weight super engineered. Had to fix right channek abd sand the idlers. Now all working except the auto stop, but U can‘t find the error🤔
I bought my 676 in 1974. I worked in an audio shop while in grade 13 and paid the "wholesale" cost. I remember the retail was similar to the number, about CDN$675, much less in the US, US$460. To clean and demagnetize the head, simply slide the piece of plastic that has the H on it to the side and lift...all is revealed. I always used CO2 tape. The recordings were VERY close to LP [Technics SL-1700 with a Pickering 881S cartridge, they're sitting beside me]. The competition was the Nakamichi 1000. My amplifier was a Marantz 1070 which got replaced by a ReVox b285 which has been replaced with a McIntosh Mac 4100 [completely restore to "new"]. When buying the Marantz, I was drooling over a $3,000 McIntosh receiver. In 1990, when I was buying the ReVox, I was drooling over another $30,000 McIntosh system. I realized by age after buying the Mac 4100 in 1995, that it was the machine I was looking at 20 years before when buying the Marantz! A friend of a friend was selling a system inherited from his father. After snapping it up and looking at the age, it was the McIntosh system I was looking at when buying the ReVox! Kismet?
I still have my dad's old McIntosh 1600 receiver, but do not use it now. It is in storage. The vintage old output tubes are no longer available. I use a modern Yaquin MC10 amplifier, and to my ears it sounds even better than the mac due to better capacitors and precision resistors. That was the biggest problem with vintage gear. Most resistors were 10 or 20% tolerance which means as they warm up the sound is totally different than when they are first turned on.
@@12voltvids The Mac 1600 had tubes? My repair guy recommended the 1400 to me as the last solid state amp. I got it off ebay as pristine, it wasn't. I had some minor things done to make it work and then something else went. I brought it to my guy who passed it on to someone who specializes in McIntosh...he even had a new glass panel that he to put in it! The list of resisters, caps, etc replaced was a page long. The "newer" McIntosh came with an MC7270 Amp and xrt 23 speakers. Records are dead silent between tracks. After 2 marriages of "turn it down" the guy died. The son didn't think it had more than 100 hours on it! Oh, and a Dual Golden 1 turntable. I was happy.
great stuff...I am trying to learn more about the inner workings of Cassette Tape Decks and to fix a couple I have at home...could be something simple as replacing belts and cleaning heads...but I wanna know the general layout of a tape deck. By the way, do all tape decks have that speed adjustment screw in them? And what causes tapes to speed up or go to slow? Many thanks from London, UK! :-)
A E S T H E T I C ... :D Great deck, most electronics of the 70s is great because it's built to last and still very mechanical (solenoids, buttons instead of MOSfets), but already quite complex. In the 80s they started to trade off at the built quality regarding home entertainment. (Plastic instead of metal/wood, less tactile "click" buttons etc. But also SMD caps which can leak onto the board and other crap which can be hard to fix)
Beautiful deck and the speakers were designed with linear phase in mind. That's why the drivers are offset. The FM input was supposed to be connected before the de emphasis network, commonly called detector out. You are taking me back to teenage years. At 16, I worked at a Radio Shack. Hey, I was 16 in 76.
Dolby FM used 25uS pre-emphasis and dolby b noise reduction. It never caught on. Back in the 70's I can remember only 1 station that was broadcasting in dolby, and that was a classical music station. I never understood what it was then because I was only about 12, but I do remember in the evening the station went off the air every night and ran sweep and test tones in the wee hours and announcements were made that this was for transmitter and receiver alignment. I never stayed up late to hear it, but did leave a reel to reel tape recording over night to hear what they did at night.
@@12voltvids we had a buffalo station that was called rock 102 on 102.5. they would say, now with Dolby, the sounds of silence. They later went automated. That was boring. Then the slogan was music and you on rock 102. The dolby was off then. Yes you needed to plug in pre, de emphasis to you don't get de emphasised twice. Quad decoders were the same because they used sub carriers, remember sca? You take me back to my forgotten past.
I have a big Sansui 9090db that has the dolby FM decoder built in. It sounded fantastic when they were still broadcasting in dolby FM. Of course I remember SCA. I did a video about SCA last week, and showed the 1 repaining SCA station still in service in Vancouver.
@@12voltvids yes well the subcarriers we're used for quadrophic sound. I think they used the both, not sure. It was a huge accomplishment that flopped. I was 17 when I fixed a sansui stereo. Huge heatsinks. It had blown outputs because his cat slept on it, blocking ventilation and filling it with fur.
The cat probably filled it with more than fur. I had a cat that used to sleep on my satellite box under the TV. One day the cat coughed up a hair ball, and other stomach contents right on the receiver. The satellite receiver caught fire and set off the smoke detectors. Good think it was one of the old metal cabinet ones.. 50 Hz to 15 kHz Main Channel (sum of all 4 channels) (LF+LR+RF+RR) signal, for mono FM listening compatibility. 23 to 53 kHz (sine quadrature subcarrier) (LF+LR) - (RF+RR) Left minus Right difference signal. This signal's modulation in algebraic sum and difference with the Main channel is used for 2 channel stereo listener compatibility. 23 to 53 kHz (cosine quadrature 38 kHz subcarrier) (LF+RR) - (LR+RF) Diagonal difference. This signal's modulation in algebraic sum and difference with the Main channel and all the other subcarriers is used for the Quadraphonic listener. 61 to 91 kHz (sine quadrature 76 kHz subcarrier) (LF+RF) - (LR+RR) Front-back difference. This signal's modulation in algebraic sum and difference with the main channel and all the other subcarriers is also used for the Quadraphonic listener. 105 kHz SCA subcarrier, phase-locked to 19 kHz pilot, for reading services for the blind, background music, etc. This is different than what SCA used. SCA used 57, 67, 91 Khz sub carriers. 57 was, and still is used for RDS data. 67 and 91 for the SCA subscription channels. of course today that spectrum is used for IBOC digital channels. They are not sub carrriers of the main program audio, but separate transmitters that operate in the spectrum where the sub carriers would have lived, so they ride along side of the main carrier. I tell you, HD radio sure sounds good. It is pretty much all I listen to these days.
Just got done with a Teac C-3X, normal bias Maxell UR tapes sound as good as what I recorded. But it's a three head deck with HX. Also I recapped it and did a full calibration with a re belt and a full disassembly and lube. Yes solenoid is a great setup. The C-3X is all solenoid as well.
Very nice presentation! I have exactly the same RS 676 AUS model, very good machine, I'm even looking for the Technics SB 6000A speakers to fill my vintage system.
I have this unit and notice when listening to a 440hz tone on line in over the headphones (record button down) that it sounds clean and balanced. When listening to a playback of the recording I hear some hissing, more on the right side. I made the recording on a type1 tape with and without dolby. The hiss with dolby is a bit less on the left but the same on the right. It's almost as if the dolby switch has zero affect on the right side. I know the right and left NR switches are working fine. I suspect an issue with the dolby block board but not sure. I did replace on cap on that board which was bulging (also looked like it had been previously replaced) but no effect. I've also cleaned the heads. Let me know if you have any thoughts. I've been browsing through the service manual. I don't have lots of experience working on audio gear but trying to learn.
The autostop rattles. I wonder if the small idler on the right side misses the grip on the metal wheel underneath the capstan🤔. If I push the plunger by hand, it works.
I do remember when I had a telephone chat with one of those audio(p.)phile fundamentalists and when explained how I achieve a flat frequency response through EQ, both hardware via component or software via PC software EQ he rejected my method alleging it's invalid. Ha... like there's a contest and rules on how to achieve such goal. I mean, buy the topmost deck, use the best magnetic tape out there, hope that Mars and the Moon are aligned after you've done your BIAS, EQ and level calibration. With PC software EQ even cassette tapes you wouldn't normally use on specific decks for recording become perfectly naturally sounding after the treatment. Of course today we can do it with digital sources as we have the necessary headroom, I wouldn't even dare to equalize frequencies below 60 Hz or push the highs from certain old analog sources.
When I was a kid my father bought this Vintage Akai GXC-725D, I'd used and abused it everyday until it wear out. It sounds great same as your cassette deck. As an electronics/Cellphone technician I' always watched tutorial videos in Yt. I just want you to know that I've learned a lot from your videos and content, totally Awesome!! Mostly on your tips and tricks in troubleshooting. What is the song in 31:32 btw? Thanks for uploading this video and more power to your channel! A fan here from the Philippines..
That was one of the first cassette deck build by Panasonic with the Technics name. Latter they dropped the " By Panasonic " moniker for Technics only !
FYI: you mention about it was difficult to clean the heads, There's a Plastic Head Cover piece, the symbol "HPF" is easily removable. If I recall you just push the plastic cover to the right and it exposes the heads, making it much easier to get to rather than the way you were showing in the video.
Working on this unit..alls working but the fast forward and rewind solenoid is not working..the relays under unit click when push controls..will work if I manually push in solenoid..any suggestions?
@@12voltvids I wish I could lol, It's probably worth that since it's an antique now. Here's an interesting tape deck if you could ever find one, Panasonic RS-296US Cassette changer.
I wonder if anyone ever made in IR receiver to plug into that back port? A remote would be a great fit considering the deck is completely solenoid actuated.
I have seen nylon ribbon used in drive belts on the Crown-corder but I suspect that the need for drive belts were killed of by the use of servo motors, I had a PHILIPS DCC900 which was servo motors throughout except for a single tiny belt which operated the tray loading but is now in need of recapping to get it to play analogue tapes as well as PASC(Precision Adaptive Sub-band Coding) encoded parallel tracks of which there are 9 one track was for the track and artist and possibly lyrics data.
Nice to see an old yewel back to live. I would know wich kind of spray you uses for cleaning contacts, a simple oil spray?. I got an Marantz tape forgotten on a shelf waiting for digitallize some tapes and I think it will need maintenance.
Great video! Your deck is sending me down memory lane as I have the exact same unit and I’m trying to rehabilitate it. I found a local repair man who used to work on them and the belts have unfortunately succumbed to dry rot. He’s looking for replacement parts. Any idea where they can be had?
I just found this deck for $19.99 in a thrift shop. I had the belts replaced and it sounds nice. Only thing is: It plays too fast The belts are available on EBAY. Just do a search.
My dad read scores of reviews before he settled on this model and we all used it throughout nthe 70's and 80's, but good things don't last. He gave it to me when the R/P switches wore out, and by then, Panasonic didn't supply parts anymore. (Yes, wore out! Cleaning no longer helped.) Sad day. Btw, all quality gear used 5% resistors by the mid-70's; it wasn't that big a deal. A better sign of quality was the semis & caps they chose. If you saw a lot of 2SC458s or C828s, throw it out.
34:27 -- Exactly!! With my mid-;ate eighties Realistic and Akai tape deck, chrome/Dolby B on (never C) to record, playback sans dolby. Cassette are a funny technology as the last mechanical audio
I have a really similar Aiwa AD-6500 deck weird front loader like yours and is it really worth restoring? it's absolutely massive and has a FeCr setting but it might not be solenoid control it's got big normal keys for it's functions. That being said it's a monster (30 pound cassette deck!!) and it seems extremely well built but needs belts and lubrication like anything from '77 would. IIRC it has a flywheel and motor in it like something from a reel to reel deck in there. Let me know what you think, and possibly where I could find a belt kit or info on belt sizes and types for it.
The construction wow, all metal. Do you know why all these vintage metals look brown/yellow, is it a special finish? Anyway, what is the name of your fancy cleaner you talking about? Nice video of an awesome product, love the construction.
I am sure it is dipped in a corossion inhibitor as steel will rust. Cleaner is either deoxit or nutrol. Those are the only 2 i use. White can is nutrol.
Search thrift stores, you'll be surprised at what shows up. Tomorrow I'll probably buy a top of the line Pioneer cassette deck from the later 70's, one with analog meters, probably in the $40 range. Needs a knob or two I think I can find. Ive found a very nice Akai reel to reel, an autoreversinf Akai cassette deck from 1980, top model that was $600 new, and a pair of in the box Infinity mid size bookshelf speakers with little dust on them, all in original plastic wrapping and instructions. It's out there.
my brother was a Marantz guy when I was a kid 40 some odd years ago, the quality of construction on that PCB board was excellent, even the capacitor legs were insulated.
Just over the weekend, I've acquired a 1976 AWA slot in cassette deck, smiular to a car cassette deck, cassette loading . It has Dolby , bias switch and EQ switch. But it not as high end as this deck. And different transport mechanism. I'm trying to find out who made the transport mechanism for AWA.
I can give you a hint as to who made it it starts with an A and it ends with an a. Oh and there's an IW between the two A's. AIWA made their own decks, they were a sister company of the Sony corporation and made a lot of products that soon found their way to carry the Sony badge.
@@12voltvidsThanks for replying, that's the thing though it's a AWA not the more common AIWA brand. I think AWA was a Australia company, but the deck is made in Japan, Apart from a mention , and some photos on Radio Museum page , I can't find any information on it.
To clean those heads the best thing is to remove the brown plastic cover above the heads. That will make head cleaning easier. I have done the same with my 671 deck. The loading system is the same as your deck. Btw... the power transformer of the 671 is placed in the top left corner. My deck has a slipping capstan. Do you know how i can fix that? The rubber seems to be in good condition. I cleaned the heads and capstan with alcohol.
I admire the technology and build quality of vintage decks. Have not seen one like that before. Good video. What is the vacuum tube amp you shown early in the video?
It is a Yaqin MC-10T and it is a FANTASTIC amp. Yaquin is a Chinese boutique amp manufacture. I have had this amp for about 10 years now, and it kicks the crap out of my old McIntosh MAC1500. That is why the MAC is in storage (to be brought out and recapped some day when I get around to it). It is pronounced Ja-Chin incidentally, and it is the engineers name who designed, and builds them. (Yaqin Ling) The company last time I did and reading up on them had about 50 engineers working there building them all by hand. This amp gets LOTS of use as it is my daily driver for music. I had 1 EL34 pop, so I changed out the pair, and other than that it has been great. There are some mods that can be done that will change the sound slightly, but I haven't seen any need to. Most of these "mods" involve changing out coupling capacitors to higher quality caps. One guy that modded his bought some audiophool capacitors and spent nearly as much on the high end caps as the amp cost, and said in the end there was a slight improvement, but not as big as he would have expected considering how much his special audiophool caps cost. So that shows that the factory ones are actually pretty good. I'm not complaining. My other tube amp is the single ended ELEKit and it also sounds fantastic, but is only 8 watts, and that kit actually cost more then this 40 watt amp. For the money I don't think anyone will dispute that you won't find a better tube amp, and when they hit the scene they had a bunch of high priced manufactures more than a little nervous.
Thanks. I have been looking for a new high quality amp and the the one you have may be what I'm looking for. I have a 1960's amp I built when I was 15 years old that uses EL84 tubes (push-pull) which I just restored to get back into tube amps. I may purchase the Yaqin MC-10T. Reasonable priced also.
Nobody around here works on vintage gear anymore, where are you located if you don't mind. I'm in southern Ontario and would like to get my old Technics deck overhauled,please reply thanx, paying customer.
Hello. I have an sanyo similar to yours.. everything works exellent. Belts, mechanical lights, meters all work excellent Meters pop up when turned on but The units output signal just went out. I cannot figure out why. Can I send you mine to fix ?
