#116061  by lunasparks
 Fri Jul 13, 2012 12:09 pm
Okay, friends...allow me to humble myself publicly. Over the past couple of days, the problem with the Q-tron+ gain began to morph into a problem with the whole rig losing its mojo. I'm scratching my head, thinking WTF??! After much puzzling and pulling and testing, it occurred to me: It's the BATTERY idiot! Yep, the battery had been slowly losing its power, first thing to go was the Q-tron sensitivity, then clarity of the cleans, then volume altogether. Now, I've been running my Moriarty Wolf for almost a year now and am on my 3rd battery. In my defense, the others died out without me experiencing it (forgot and left plugged in, so easy to forget). I guess I had somehow thought that the buffer would basically do it's job and then just kind of die out in a single "poof" -- who knows why I assumed this. :?

Anyway, I threw in a new 9-volt, powered up and the rig was suddenly louder than all hell (lost volume found), tone was recovered, and I flipped on the Q-tron+ and dialed in something much better with gain about 9-10 o'clock (still have to work it a little higher for my non-buffered strat, though those pickups are pretty far away relatively). It's still not perfect and always so touch-sensitive, but I think Problem Solved, more or less.

Thanks for those who offered tips...and sorry for being completely clueless!!!
 #116063  by Tennessee Jedi
 Fri Jul 13, 2012 12:20 pm
The rigs are complicated .... us mere mortals get confused easily :D
Heck I am fretting about wiring up to speakers !
Yeah my battery did the slow death thing and I too questioned every aspect of my rig 1st before sussing it out
Glad its working better for you .....
 #116093  by JonnyBoy
 Sat Jul 14, 2012 2:26 pm
I was just about to start playing at a gig and I had everything all done and set up I thought... I checked all the connections (I thought) and I deemed my rig broke and I was freaking out. I went out to get my Crate power block and when I went to hook the speakers up, I found out I had not put them into the banana jacks. DUH! Now anytime I have a glitch, my band mates take me way less than serious about my issues.... Damn Jerry rigs...
 #129632  by lunasparks
 Fri Jun 28, 2013 8:17 am
Well, I just wrote a long post and lost it. Ugh. Here we go again.

I've never been able to get a really usable tone from my old big-box Q-tron+ and last night I cracked it open to have a look inside. Nothing noticeably wrong, for better or worse. While I was in there I poked around a bit and ended up modding the red LED light that's always on to just come on when the pedal is engaged, but no fix for the muddy tone.

Then I woke up to a thought this morning...the TRIMPOT! While I was in there I noticed a little trimpot about dead center of the board. What if the guy before me had messed with it and screwed up the envelope somehow? This morning I put the theory to the test as follows:

1) I put the settings in Jerry territory (cribbed from a pic Waldo posted in another thread):
2) Flipped it over, removed the back cover to reveal the backside of the circuit board:
3) Zeroed in on the trimpot, little white arrow in pic below:
4) I took a tiny screwdriver and started dialing the pot back...it was at about 2 o'clock when I started, currently at about 8:30 or so. EDIT: if picture is posting sideways, imagine a turn counterclockwise so arrow tip is at 8:30.

I still don't have it dialed in but I think this is the whole problem I've had. Dialing back the pot reduces bass mud and allows the envelope to open at higher frequencies so you can play past the 12th fret. A little turn goes a long way and it's very sensitive, but I'm getting close to something usable, finally! Clip below has two sections, one at 5-8th frets and second at 12-15th frets, both with a little clean tone to establish a baseline.

https://soundcloud.com/lunasparks/2013- ... tron-test1

I exchanged some PMs with Waldo this morning and he thinks this may be the fix for issues a lot of people have with this unit and the original big-box Qtron. In any event, hopefully it helps someone else!
Last edited by lunasparks on Fri Jun 28, 2013 1:46 pm, edited 1 time in total.
 #129678  by lunasparks
 Sat Jun 29, 2013 5:26 am
PaulJay wrote:Just thought if you knew someone that had another one like yours you could compare them with your rig. But, you probably thought of that already. Hope you resolve it soon. ,Paul
Gotcha, I couldn't tell from the post if you had something else in mind. I think I've got it sounding pretty good, but if anyone reading this is game for opening up their Qtron and taking a picture or describing the position of their trimpot I'd be interested in that information. Certainly possible there's variability in the circuits & components over time so copying settings wouldn't make sense, but would be good to have the information anyway, especially if said Qtron is deemed to be well-calibrated (i.e. "it's the shit!").