Hi there,
So I have a Tascam Portastudio 414 mkII that I've been trying to use for quite some time, and have never been able to get to work properly. I'm about ready to throw the thing in the trash. The instruction manual assumes a previous general working knowledge of recording, which I definitely don't have.My main issue is that when I do finally figure out how to set something down to the tape and play it back, there is a very loud buzz in the background that overwhelms my vocal input. I've tried adjusting the trim and fader and master volume controls, and while lowering them makes the buzz softer, the vocals are much too quiet to hear. I'm fairly certain it's not the microphone, because I hear this buzz in the background of my headphones even when I'm not recording and have it in "safe"mode and I simply have the monitor turned on. The buzz also continues when I listen to the tape past where I've recorded. It's also true when I try to record a guitar line as a direct input. I'm trying to figure out if it could be some sort of interference, but I can't come up with anything. Any help you have would be highly appreciated. Ideally I want to figure out how to record guitar input on one track and vocals on another simultaneously, but at this point just setting down a vocal track is driving me up a wall.
That sounds exactly like a ground loop or RFI problem (RFI= Radio Frequency Interference).
You've either got a ground loop somewhere, or are on a power outlet shared by some heavy duty equipment in your house (refrigerator, A/C, furnace, etc.), or have some serious RFI problems from nearby power stations or radio/TV transmitter towers.
Tracking down problems of this nature is a process of elimination. First, make sure it's not a problem with your headphones (like a bad cable) by plugging the headphones into another stereo system or portable player or whatever to see if you hear buzz from those through your headphones.
Once you have determined that the headphones are OK, then just plug those into your Portastudio (PS from now on) and plug your PS into a power outlet. Don't plug anything else into the PS yet. Without playing a tape, power up the PS and go into input monitor mode and crank up the gain and/or faders on channels to see if you can hear the buzz. With the gain cranked to the max, you should really only hear some white noise and maybe a little bit of buzz. If you've got loud buzz, even without turning up the volume very much, then either you've got a grounding problem, dirty power, or some serious RFI.
If you are getting that buzz without doing anything other than monitoring inputs, then try some different outlets in your house, or physically move the PS around to different locations. If it's RFI, the level of the noise will change as you move around. If it's a ground issue that's external to the PS, then a different outlet might fix it. If it's dirty power from something else on the same circuit, moving to an outlet on a different circuit should correct it. If none of those things helps, then it could also be some faulty wiring inside the PS or a bad power supply, in which case there won't be much you can do.
If you didn't get the noise problems from the first step, then put a blank tape in the PS, hit play and turn up the volume for the tape tracks. If you are now hearing the buzz, then it could be that the tape head is picking up RFI. Again, try physically moving the PS around the room or to different rooms. If the level of the buzz changes, then it's most likely RFI being picked up by the tape head. The best solution for that is to try to find the physical location in your house where you get the least amount of RFI noise. A good power conditioner / line filter might help a bit as well.
If you still aren't getting any noise, then you can try plugging in the microphone and testing with that. If you start getting noise now, then you've probably got a bad mic cable that's picking up RFI noise. Again, try moving around to see if the problem gets better or worse, and try a different mic cable. If it's a decent quality microphone, then the microphone shouldn't be the problem.
The guitar would be the last thing to check, but certain types of guitar pickups are notorious for picking up hum and buzz from regular household stuff, such as lights. Just turning your body while holding the guitar can significantly change how much RFI you pick up through the guitar. Also, check the cable and see if a different cable makes any difference.
If the root cause is dirty power in the house, consider investing in a good quality power conditioning power supply or power strip. Look for one that has noise filtering. If you want to go to the extreme, you can get a balanced power isolation transformer power supply for your studio. I have two 20 amp balanced power transformers running my studio. I didn't really have any noise problems to begin with, but what little noise floor I did have was reduced significantly with the transformers, and balanced power definitely helped with a couple of old sound modules and synths that had low level buzzes.
Good luck!