Tascam 388 Stereo Output Issue - No R output

edwood83

New member
Hey guys-

I'm having some issues with my 388 and I'm wondering if anyone here might have some insight. The unit records perfectly fine, even when I'm having these output problems. What's happening is that is just not outputting to one side or the other, intermittently.

Example: I assign track 1 to the 1-2 bus, record with its balance all the way to the left (odd) and track 2 to the same bus, and record with its balance all the way to the right (even). When I play it back (assigns off) without changing the balance, I will hear track 1 (L) but not track 2 (R). As I turn track 2's balance to the left, the audio will start to come in on the left. Through all of this, the track 2 meter is registering the recorded audio, as it should. The master Right meter, however, registers nothing. Pressing the mono button will then give me audio from the right side (and the meter will show it), but only if I turn the balance on the track in question towards the left; max level comes with center positioning.

The tricky thing about this is that it had happened years before, except not outputting on the left rather than the right. Being that I had just started college, I couldn't use it regularly and it would take me months to complete my work, so I would just work in mono and then wait for a day when it was cooperating to mix off the tape. Of course, it just went away on its own just as I came home with some time to fix it and so I thought it was just a fluke. Now (7 years later) it started again a few months ago; I put fader lube on all sliders and it went away. I thought that had solved the issue, but today's application of fader lube did nothing. In fact, in just playing with the unit, I have had the issue swap sides on me twice today, but mostly occurring on the right.

Sometimes you can ever so faintly hear a track that is turned all the way to the right, but it is grossly less intense than the left output level. I have tried both the stereo L-R output and monitor L-R output in the rear of the unit to see if it might have been that set of jacks, but both exhibit the same issue. Same for the headphones- still faint to nothing on the right side.

I also tested my right ear, and it is working. ;)

Any help would be greatly appreciated...

Thanks,

-Ed
 
The Downward Spiral...signal into tracks no working

No improvements on the original issue posted above, and now one more thing is happening.

When I try to record on any track, the input signal registers on the master L-R meters but not the individual track meter. The input sound also does not come through the monitors. After recording, playback yields just the faintest sound of the new recording. All existing tracks playback fine (as long as they are all the way to the left or on mono, of course.)

Anyone? Is there some main component that might be going that I can hopefully replace?

I just broke up with my girlfriend a few days ago, I hope this isn't the end of my relationship with my 388, too...

Thanks, guys.

-Ed
 
Ed,

Goodness...I wish I had a 388 so I could be of more direct help.

Do you have a manual?

Some general suggestions:

1. I've forgotten...are there individual track direct outs on the 388? If so, can you hear newly recorded tracks through those outputs?

2. Have you/are you comfortable opening it up and visually inspecting it? If you are, have a look or smell for anything scorched or burned...look for capacitors that are bulging at the ends like the ones in the pictures on this webpage. Look for bad solder traces on the PC boards. Get some DeOxit and conservatively apply it to multipin connectors (disconnect connectors first, apply DeOxit, wipe up excess, seat and reseat the connector or card). While you are at it, look at and feel the solder-mount side of the connector to see if there are cold solder joints.

Oxidized connections, cold solder joints, these things can drive you batty. I was having really wierd "ghost in the machine" issues with my 58, but cleaning the relays with DeOxit, resoldering all the amp card multipin connector solder joints and applying DeOxit to the connectors made it well again. Make sure, of course, that 388 is disconnected from power when you do this. Take your time and enjoy getting to know the innards of 388 if you don't already.

Not comfortable opening 388 up? Let's talk.

If anything I wrote above does not make sense, ask okay? I'm no smarty-pants, just trying to get some ideas flowing and learning your experience level at the same time.

BTW, welcome to the analog only forum!

Other ideas anybody? :confused:
 
Yeah, the 388 does have individual outputs. While I haven't tested whether the outs are giving me any sound, I would guess not. The individual meters are registering little to no sound; the best I can get off a decent input signal is a faint recording that requires me to turn everything all the way up to hear it. I will test the outputs to make sure. Also, when recording in, the signal shows up on the master meters but I still don't hear it through the monitors, which is odd.

I'm definitely up for taking the thing apart, I just wanted to see if anyone else had experienced the same or similar problems before I get in there. I'm hoping to get to it tonight, otherwise it has to wait for next week. (Bummer, too, had a session lined up :( )

Thanks for the cleaning tip, I will definitely do that while I'm in there. I'll look out for dead caps and resistors, too. I have a manual so I'll reference that for functionality, I was just hoping that someone might have a little more direction for me in the interest of saving time, you know?

Anyway, I'll post back after I get it apart and let everyone know what I've found. Thanks for the welcome!
 
Not sure if this applies but...

Check this out as posted in another thread by A Reel Person:

Check that no Red "L/R Stereo" assign button is depressed simultaneously as the White "1/2, 3/4, 5/6, 7/8" assign buttons are pressed on any channel.

The L/R Stereo and Monitor subsystems share the same internal Master L/R-buss signal route to the outside world. Pressing any White assign button simultaneously as any Red assign button causes the 388 to go into auto-mute, to prevent an internal feedback loop.

That's my 2¢ about one of the major "gotchas" in operation that's not clearly stated in the manual.

On the Monitor subsystem, you must also use the headphone level control for overall levels, w/headphone section set to "Stereo".

Keep us posted. I'll be watching.
 
Ok, thanks, guys. I just went down to my basement to take it apart and decided, hey let's test it one more time.

Of course it decides to work today, so I'm taking this opportunity to record some stuff. If it stops working tonight, I'll take 'er apart but otherwise, I'll do it early next week and I'll definitely post back. Hopefully I dig up some useful info.

Thanks again and talk to you soon...

-Ed
 
Yup, it does sound like bad solder joints, 'intermittent' being the key word here but, again, it can be a number of other issues noted above.:eek:

----
 
Ed,

The good news is that it is not a mechanical issue (can be very costly), and that it is not a failed electrical component, because if you had burned out SC's or IC's burned is burned. Like cjacek or Reel said, fuses or bad solder joints are the place to start. It can take time, but if your unit is functioning today, it will just be a matter of time to chase down the culprit, but it can be chased down. Think of it like a 50,000 piece puzzle. :eek: :p Sometimes you can come upon good fortune too and it is a 100 piece puzzle, but in either case the puzzle can be finished. :)
 
I think it's working!

Hey guys!

So this took two months instead of the week I thought it would...too much crazy traveling for work. At one point I was in Puerto Rico for less than 24 hours.

Bad news: I won't be buying any more gear for a while because of the Good News: I quit my job Friday. So, of course, now I finally found the time to finish the cleaning process I started sometime in June.

Three little cans of deoxit and two repaired solder joints later, it appears to be working. Unfortunately I won't really know until a few months of use but for now, it's good. Thanks for the suggestions and the help!

Let me ask one more question, if anyone comes back to read this:

I had the unit on its side for most of the cleaning process, because that was the only way to feasibly remove some of the cards. Is that bad for the tape mechanism in any way? I haven't noticed any problems but again, I've been using it for a day.

Thanks again,

-Ed:D:D

Ed,

Goodness...I wish I had a 388 so I could be of more direct help.

Do you have a manual?

Some general suggestions:

1. I've forgotten...are there individual track direct outs on the 388? If so, can you hear newly recorded tracks through those outputs?

2. Have you/are you comfortable opening it up and visually inspecting it? If you are, have a look or smell for anything scorched or burned...look for capacitors that are bulging at the ends like the ones in the pictures on Analogrules.com Look for bad solder traces on the PC boards. Get some DeOxit and conservatively apply it to multipin connectors (disconnect connectors first, apply DeOxit, wipe up excess, seat and reseat the connector or card). While you are at it, look at and feel the solder-mount side of the connector to see if there are cold solder joints.

Oxidized connections, cold solder joints, these things can drive you batty. I was having really wierd "ghost in the machine" issues with my 58, but cleaning the relays with DeOxit, resoldering all the amp card multipin connector solder joints and applying DeOxit to the connectors made it well again. Make sure, of course, that 388 is disconnected from power when you do this. Take your time and enjoy getting to know the innards of 388 if you don't already.

Not comfortable opening 388 up? Let's talk.

If anything I wrote above does not make sense, ask okay? I'm no smarty-pants, just trying to get some ideas flowing and learning your experience level at the same time.

BTW, welcome to the analog only forum!

Other ideas anybody? :confused:
 
Congratulations x2 I suppose! :D

So you had the 388 like tipped up on an end, like on the right or left side?

I wouldn't recommend running tape with the unit like that just because the tape path was designed to handle tape with gravity pulling down the way it does when the unit is sitting normally, but even running it short term wouldn't/shouldn't cause problems. I realize you're not saying you did or would run tape with it sitting upright, I'm just trying to drive home the point that having it sit like and you're not even running tape really shouldn't be a problem at all.

Other opinions guys?
 
No problem with that.

It must have been sitting upright on it's back end, the thick end. Center of gravity's down there, anyway.:eek:;)
 
Hey, I'm having the same problem (intermittent R output loss). Where did you de-oxit and solder? (hopefully so i'll have less poking around to do)
Thanks!
 
Is there any more specific information that you could give on your fix? I'm having the same problem with my 388 now. There is no output from the Right channel, unless I switch to mono, then it works fine.

Thanks
 
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