Solid State Guitar Amp Forum | DIY Guitar Amplifiers

Solid State Amplifiers => The Newcomer's Forum => Topic started by: audifanatic on July 18, 2014, 12:48:09 AM

Title: Bucking noise on Epiphone Studio 10S
Post by: audifanatic on July 18, 2014, 12:48:09 AM
I've recently decided to get back into guitar now that school is out for the summer (we'll see if I actually keep my promise, I say I'm gonna do a lot of things every summer). Anyway, so a few months back, I turned on my amp and I got an extremely loud bucking sounds out of it as shown in this video: https://vid.me/ubh

I know it's a pretty lousy amp, but I want to try repairing it for educational purposes more than anything else. I'm a senior computer engineering major and my analog electronics could use a bit of a refresher.

If it helps anyone out, Gibson provided a schematic for the Studio 10. I presume the 10S is the same amp, just in a slimmer form factor. http://www.gibson.com/Files/schematics/Studio%2010.jpg

I presume bad capacitors are to blame; the amp has been sitting for about 5 or 6 years (college really takes a toll on your hobbies lol). Last time I opened it up, some of the caps near the power supply looked slightly bulged. Apparently I've heard that they can sometimes go bad after remaining unused for extended periods of time.
Title: Re: Bucking noise on Epiphone Studio 10S
Post by: J M Fahey on July 18, 2014, 07:29:37 AM
Sorry but canĀ“t load your video.
Could you just upload the audio (say, as an MP3?) somewhere else ... or even straight here as an attachment?
Thanks.
Title: Re: Bucking noise on Epiphone Studio 10S
Post by: audifanatic on July 18, 2014, 10:36:03 AM
Hmm, that's interesting.
I uploaded the mp3 version with this post. Though I am going to re-upload it to that video site to see if anything changes. I prefer you view the video so that you can see how the noise changes as I adjust the knobs on the amp.
Title: Re: Bucking noise on Epiphone Studio 10S
Post by: audifanatic on July 18, 2014, 10:40:15 AM
Try this link for the video: https://vid.me/e/ubh
If it doesn't work the first time, refresh the page, that's what I've been having to do (I'm using Firefox).
Title: Re: Bucking noise on Epiphone Studio 10S
Post by: audifanatic on July 19, 2014, 12:32:27 AM
So I took it apart today and I saw and I saw two bulged capacitors (both of them 2200uF, right next to each other). All the other ones look fine. So I ordered some new caps online and I'll be replacing them on Wednesday probably. Hopefully that's the only problem, I'll post an update when I install the caps.