TASCAM 48-OB Manual

[Monkey Allen]

Hi. I just bought a really great condition Tascam 48 with a couple of Tascam DX-4D noise reduction units (probably won't use them), a new reel of tape, some empty reels, the remote, cables snakes etc...but the manual is the comprehensive Tascam 48-L manual. Not the 48-OB edition. I guess somewhere over the last 40 years the original got lost and the L was sourced as a replacement.

So, I'm just asking if anyone has the manual or knows where to get one? Tricky to find a pdf since there are stacks of fold out schematics etc. The L manual is about 3/4 inch thick and has oodles of fold out sections. I think it covers plenty of operational stuff much like the 48-OB but I would like the actual 48-OB manual.

By the way I tried using search but keep getting a 403 Forbidden error.

Thanks

 

[sweetbeats]

I’d call Tascam Parts directly and ask if they have any. They may at least have a high quality official reprint…the large tabloid fold-out pages would be full size. Call them and report back here what you find out.

 

[RRuskin]

Probably the only difference between the 2 machines is that the OB has XLR in/outs while the other has rca's.

 

[Monkey Allen]

Yep. I'm interested in the charts for the XLR i/o. And yep, have been on Tascam Parts. Can't call em. I'm in Australia. I could email them and see what 48-OB stuff they have. Searching their website doesn't bring anything up.

 

[RRuskin]

As I recall, TASCAM was wiring their XLR'S Pin 3 Hot. Also, the XLR outs don't enhance the tape machine's performance in any way. In fact, they degrade it ever so slightly. The XLR's just make it easier to interface with +4 equipment. If using a TASCAM or Mackie class console, the rca in/outs are the way to go.

 

[Monkey Allen]

Yep, I've heard something similar to what you're saying.

Incidentally, "Scribd" website has a 143 page 48-OB manual but you need to sign on and 30 trial up etc.

 

[sweetbeats]

Yep. I'm interested in the charts for the XLR i/o. And yep, have been on Tascam Parts. Can't call em. I'm in Australia. I could email them and see what 48-OB stuff they have. Searching their website doesn't bring anything up.

You can call internationally, no?

All of the amplifier circuitry for the balanced I/O is on the amp card, J005 pin 3 (“OUT ‘H’”) and pin 2 (“OUT ‘L’”). Do your schematics show these elements? If so then you’ve got all the information about the balanced circuitry. The XLR jacks themselves literally plug in to the motherboard directly and then traces on the motherboard go to the ground plane and P005 pins 2 and 3. So there is nothing but connector, trace and wire between the amp card and the jacks.

 

[Monkey Allen]

You can call internationally, no?

All of the amplifier circuitry for the balanced I/O is on the amp card, J005 pin 3 (“OUT ‘H’”) and pin 2 (“OUT ‘L’”). Do your schematics show these elements? If so then you’ve got all the information about the balanced circuitry. The XLR jacks themselves literally plug in to the motherboard directly and then traces on the motherboard go to the ground plane and P005 pins 2 and 3. So there is nothing but connector, trace and wire between the amp card and the jacks.

Yeah I could. Seems weird though when I can search the site and send an email.

I have this issue with track 5 where the RCA output is very, very quiet and the XLR output is very loud. Just trying to work out why. I can send track 6 through RCA 5 output and it's fine. But conversely if I send track 5 through the RCA output 6 I get the same very low volume.

 

[sweetbeats]

There is nothing weird about picking up a phone and calling. I think the opposite…odd not to when you can. Tascam has never been as good about following up to emails as they have answering the phone…it’s been a few years since I’ve had need to call so maybe things are different now I don’t know…but I’ve always recommended to just call and ask vs the more passive approach with email. If you’ve sent an email maybe give it a couple business days to see if they respond and if not just call them?

Does your output problem follow a card swap? Or is that what you’re saying when you mention sending track 5 to output 6? I’m not sure how you get a tape track to a different output, so maybe you can clarify what you’re talking about. But try moving the channel 5 amp card to a different slot and if the problem follows the card then you have an issue with the amp card. If the problem doesn’t move it’s an issue with something in between the amp card and the jacks.

 

[Monkey Allen]

I haven't made a card swap as yet. I got it wrong earlier regarding sending track 5 to output 6. That's an error. So yeah, I'll swap cards in due course. I have a couple of other things to do first though.

 

[Monkey Allen]

I swapped card 5 to 6 and 6 to 5. The issue follows the card.

 

[BeatleFred]

The original Tascam 48 manual includes both the operating & service manual in a black binder. It has many fold out pages,
so its not an easy task for anyone to volunteer their time to make a xerox copy or scan of all the pages. The black binder is
the same for other models made at that time, such as M-512, M-308 mixers, etc..

Back in the 90's I called Tascam a few times and bought xerox copies of various manuals that they sent to me in the postal mail, which
I still have in my collection of Teac/Tascam literature.

I imagine they still provide/sell xerox copies, otherwise check Ebay, or HiFi engine:

https://www.hifiengine.com/manual_library/tascam/48.shtml

Ps: not everyone is aware of it, but there is a manufacturing date code for many Teac/Tascam units, usually a two digit number
to the right side of the main serial #. I think some later models in the 90's had three digits.

If you're curious when your 48 was made, look for the two digit #. To use an example, if you see 62, it means it was manufactured in
the 2nd quarter of 1986. 6 means 198->6 and 2 means 2nd quarter of that year. Likewise a 71, means the 1st quarter of '87.

I found out this info because I was curious about it back in the 90's and when I called Tascam to order some manual copies, the
rep on the phone told me of the code. Basically, the Tascam 48 was made from 1984-87 for sure, and perhaps the first ones arrived
in '83 and the last in '88. The last eight track made was the TSR-8, which came out in 1989.

There might some revisions in the black binder manuals during the time the 48 was made. Outwardly, nothing was changed, but inside,
could be some slight differences? I only mention it because I have seen two Tascam 48 binders, one with a print date of '84 and another
in '87.

 

[Monkey Allen]

Thanks. Hifiengine is not taking anymore sign ups/ accounts/ registrations for now. On the manual...yep I appreciate it is a very substantial document. The original 48L manual I have right here is riddled with large fold outs and is a hefty lump itself.

As for contacting Tascam, I was of the impression that since its 2026 they no longer come to the party when people seek manuals from 1984. In the 90's...yep I can see they would. but today, I kind of think not.

My machine comes from the 3rd quarter of 1984 based on your dating tip. Thanks.

"Scribbd" has a manual that you can read online but the resolution is no good. And there is no way of knowing if the actual download (you need to sign up and provide CC details etc) is sufficiently high res to be useful.

I'd be quite willing to pay for a quality PDF but I can't even find that.

Anyway, with further testing it seems to me that the RCA out on card 5 is extremely weak. low in volume. That's the fault I'm looking at. Of course...there may be other factors lurking but off the tape the low RCA ouput volume follows that card. I've ruled out that there is any issue with the XLR output from card 5. I thought there was but there is not. So that comes down to one fault and trial and error shows it must be the card - through card 5 the RCA volume is very, very low. The rest of the machine is cool.

 

[Manslick]

Try looking HERE

or Maybe HERE

 

[Monkey Allen]

Thanks manslick...couldn't see anything on the first link. I have seen that 2nd link but it's from 2016 and I did not think that $75 manual would still be for sale. I could try to PM the seller I guess.

 

[Monkey Allen]

Ok fellas...just as a heads up...I've been lucky enough to have a manual and revision doc find me.

Also on my issue here...on the cards there is a white button S001 that can either be +4 or +8. I've just realised my problematic card is set to +4 while the working card I'm using as a comparison is set to +8. So this is an interesting finding. Not sure it fully explains my very low RCA output/vol issues in the problematic card. But it is the first solid discrepancy I've found. I measured about 10-15 components before I spotted that.

EDIT: But then I discover that every other card in the deck is at the depressed +4 position and that the problem card was also at +4 and that the comparison card, card 6 is the anomaly at +8. So...no idea what to make of that.

 

[Monkey Allen]

Well this is not going to shock any of the old hands I wouldn't imagine...but pulling the thread of the card 5 RCA output issue has seen me running more comprehensive tests...conclusion: I got badly burnt.

I'm gonna take it to a tech.