Boss DR-110 Drum Machine - Slight noise in output

Aaron · Joined: Nov 08, 2012 Posts: 3 Location: Phoenix, AZ

Hi all, this is my fist post here.

I just acquired a Boss DR-110, and the output is a little noisy, at least to my ear. When you have the headphones in and just listen for awhile (with no pattern playing), you will occasionally hear a little pop or two, just a little bit of noise (there's also a constant and very mild hiss, but I don't mind that). The noise happens sporadically, and it's rather quiet, but you can sometimes hear it during playback.

As an aside, I should note that before I could even use the machine, I had to re-solder the joints connecting the headphone jack to the PCB. When I got it, you had to wiggle and hold the headphones at a certain angle just to get any sound out of the jack. I figured that cold or broken solder joints were the problem, and I was right. But I've also got this noise problem. I don't know, however, whether the noise existed before I fixed the headphone jack.

Any idea why I'm getting the intermittent noise described above? Any suggestions you can offer would be appreciated.

Thanks!

Aaron

Blue Hell · Posted: Thu Nov 08, 2012 1:12 pm Post subject:

Aaron

1980 .. might just be a lil noisy by nature?

Aaron · Joined: Nov 08, 2012 Posts: 3 Location: Phoenix, AZ

Aaron · Joined: Nov 08, 2012 Posts: 3 Location: Phoenix, AZ

Well, today I replaced the electrolytic capacitors in the little headphone-amp circuit (C64, C65, and C68). I was going to change the amp chip, too, but as it turns out, I have one of the later serial numbers that uses a different one than is shown on the schematic. The schematic shows LM386N-1, but mine uses M50501L. The latter is apparently pretty exotic (or just obsolete) because it's hard to find on the Internet. OTOH, I found an LM386N-1 at Radio Shack! Laughing

I also unsoldered and resoldered the headphone jack, just in case there were any bad solder joints.

Anyway, none of these steps helped. Still getting the noise through the headphone jack. As it turns out, though, the signal is very clean and quiet through the 1/4" output jack. I ran it through an amp tonight and it sounded great. Since I'll use that jack to record anyway, I suppose it doesn't matter about the headphone jack. But I'd still like it to work properly. Cool

Still welcoming any ideas on the noisy headphone jack!

Aaron

Blue Hell · Posted: Fri Nov 09, 2012 3:55 am Post subject:

[quote="Aaron"Anyway, I can read a schematic and I'm pretty handy with a soldering iron[/quote]

Sure looks like that Cool