tube fanatic Posted August 2, 2015 Share Posted August 2, 2015 I was putting my thoughts together for a thread on this topic when I was alerted to something similar which just came up on AA: http://www.audioasylum.com/cgi/vt.mpl?f=tubes&m=253369 That thread doesn't address the possibility of resistors, capacitors, poor or cold solder joints and sundry other things being the cause of issues as well. We can discuss those issues in a subsequent thread here. Maynard Quote Link to comment Share on other sites More sharing options...
erik2A3 Posted August 2, 2015 Share Posted August 2, 2015 Maynard: Just to give credit where deserved: the author of that audioasylum thread does in fact mention poor solder connections in the first example provided, but seemed to limit them to tube socket pins. By implication, I guess I still perceive that statement as referring to other connections, as well. Quote Link to comment Share on other sites More sharing options...
Luv_sum_Horns Posted August 2, 2015 Share Posted August 2, 2015 Maynard, I anxiously await your write-up. Being curious to hear the "tube sound" and having nothing available locally, I purchased a Yaqin EL84 based SET. Unfortunately, it took a whack on its head during transit and has a subtle ticking in the left channel. Being new to tubes I blew if off as something happened to a tube. Replaced the el84's with JJ's and the 12AX7's with Sovtecs. Improved the sound quality that was already pretty good, but the ticking persists. OK, maybe it took a really good whack and an already suspect joint came loose so I reflowed everything I could find on the left side. Ticking persists. Suspecting a faulty component at this point and I am tapped out as far as my electronic skills go. Luckily have a shop not too far away. Lesson I learned here, if you get an amp with an issue, just send it back and eat the shipping. The company I bought it from was willing to replace so they are on the up and up, but I figured it was something obvious as it wasn't flaming out or blowing my speakers up. The other lesson learned was don't over estimate your fixin' skills. Quote Link to comment Share on other sites More sharing options...
Guest thesloth Posted August 2, 2015 Share Posted August 2, 2015 Ticking? Can you upload pictures? Does it sound like a motorboat? Like putt-putt-putt-putt-putt? Possibly could be a decoupling cap. Try and take some pictures of the inside of the amp. Is this an EL34 SET? or EL84 SET. The latter would only have like 2 watts output. Quote Link to comment Share on other sites More sharing options...
Luv_sum_Horns Posted August 2, 2015 Share Posted August 2, 2015 It's a Yaqin MC-84L (EL84). The sound is definately left channel and sounds to me like a just slightly audible tick. Sometimes they are single ticks, sometimes a burst of ticks and completely intermittent. My friend who actually has electronic skills refers to it as an arc. I arc frequently on light switches but the tick is more subtle than that. Like some component getting a little too much juice and releasing into the left channel. It is at a steady volume meaning it remains at a low level as I increase volume. That seems to indicate it's not power supply related but a component in the chain. Replaced caps on my Heresys so I have an idea how out of spec caps affect sound and they definately don't cause ticking. Bad resistor, no idea, same with the transformers, I was using it in a biamp setup on my Cornwall woofers and it was even more subtle but still there, so it's in the roll off (guessing 600-800hz) area. Quote Link to comment Share on other sites More sharing options...
Luv_sum_Horns Posted August 2, 2015 Share Posted August 2, 2015 Thought I attached a jpg? Its this one: http://www.amazon.com/YAQIN-MC-84L-Vacuum-Integrated-Amplifier/dp/B00A7IZV22/ref=sr_1_1?ie=UTF8&qid=1438534039&sr=8-1&keywords=yaqin+mc84 Quote Link to comment Share on other sites More sharing options...
Guest thesloth Posted August 2, 2015 Share Posted August 2, 2015 If you think it's arcing open the think up and run it with the light out. Check around the tube sockets for carbon from arcing. Quote Link to comment Share on other sites More sharing options...
Luv_sum_Horns Posted August 2, 2015 Share Posted August 2, 2015 Sorry but I meant to say take the bottom cover off being a tube amp and look inside in the dark for any arcing. Yeah, that was my next step. I'm in no big hurry as that Torii prematurely added to my sig arrives on Wednesday and my other amp still isn't broken in. If push comes to shove, I'll drop it off at the shop. Failing that, there's always a use for a mono somewhere. Quote Link to comment Share on other sites More sharing options...
tube fanatic Posted August 2, 2015 Author Share Posted August 2, 2015 Maynard, I anxiously await your write-up. Being curious to hear the "tube sound" and having nothing available locally, I purchased a Yaqin EL84 based SET. Unfortunately, it took a whack on its head during transit and has a subtle ticking in the left channel. Being new to tubes I blew if off as something happened to a tube. Replaced the el84's with JJ's and the 12AX7's with Sovtecs. Improved the sound quality that was already pretty good, but the ticking persists. OK, maybe it took a really good whack and an already suspect joint came loose so I reflowed everything I could find on the left side. Ticking persists. Suspecting a faulty component at this point and I am tapped out as far as my electronic skills go. Luckily have a shop not too far away. Lesson I learned here, if you get an amp with an issue, just send it back and eat the shipping. The company I bought it from was willing to replace so they are on the up and up, but I figured it was something obvious as it wasn't flaming out or blowing my speakers up. The other lesson learned was don't over estimate your fixin' skills. If you take off the bottom cover you will access the underside of the circuit board, wiring, etc. Use a wood dowel, or any other kind of insulated tool (even a rigid plastic drinking straw can work) to gently push down, or tap, on the board in various locations around the channel from which you hear the ticking. Of course, a speaker needs to be connected. If that doesn't produce any change, gently move the wires around using the tool. What we're looking for here is any change in what you are hearing. If it stays the same, my thinking is that you have a bad cap in the signal path. Let us know what you encounter, and be careful to follow the safety instructions in the thread Sloth started! Maynard 1 Quote Link to comment Share on other sites More sharing options...
mike stehr Posted August 3, 2015 Share Posted August 3, 2015 If it has a printed circuit board, it may have been cracked when it got slammed in transit... Quote Link to comment Share on other sites More sharing options...
Luv_sum_Horns Posted August 3, 2015 Share Posted August 3, 2015 If it has a printed circuit board, it may have been cracked when it got slammed in transit... Lol, that's exactly my type of "luck". Thanks for all the replies. I'll have a lights out session with a popsicle stick. Wow, that came out wrong! -bill Quote Link to comment Share on other sites More sharing options...
Dr Morbius Posted August 8, 2015 Share Posted August 8, 2015 So, it's 5 days later……………..what's happening'? Quote Link to comment Share on other sites More sharing options...
Coytee Posted August 8, 2015 Share Posted August 8, 2015 Clearly the popsicle stick is a factor. 1 Quote Link to comment Share on other sites More sharing options...
Luv_sum_Horns Posted August 9, 2015 Share Posted August 9, 2015 Clearly the popsicle stick is a factor. Too funny! I have only one thing to say about this: SPLINTERS! Actually I ordered a Torii dual mono from Decware and it arrived a day early. Rack reconfigure to accommodate two space heaters and returning configuration to a somewhat normal level for auditioning. My audio world is currently in turmoil. I'll try to get to this in the next week. Quote Link to comment Share on other sites More sharing options...
Ski Bum Posted August 9, 2015 Share Posted August 9, 2015 Decware still ship in those hard sided pelican briefcase thingies? That's a nice touch to ensure they are UPS-proof. Quote Link to comment Share on other sites More sharing options...
Luv_sum_Horns Posted August 9, 2015 Share Posted August 9, 2015 Decware still ship in those hard sided pelican briefcase thingies? That's a nice touch to ensure they are UPS-proof. Threw it in free, well for a huge stack of Benjamins. Decware is a pleasure to deal with. The first amp they sent was really well packed, so I wasn't concerned. Separate emails when they picked the parts, assembled, tested, and QC'd. -bill Quote Link to comment Share on other sites More sharing options...
Luv_sum_Horns Posted August 12, 2015 Share Posted August 12, 2015 OK so I got the amp hooked back up, bottom plate off, lights out. I see nothing. Couldn't find my popsicle stick so I poked around with half of a chopstick (one handed because I am that paranoid) . The mainboard seems to be quite solid, and putting pressure in different places didn't change anything. Wiggling wires around had no effect. I'll be finding out if my local fix it shop is any good. In the meantime, I have two other amps that need to be broken in. Thanks for the pointers guys! I was hoping for something apparent and easy to fix. -bill Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.