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Did an outdoor gig on Rue Châtelain here in Laon tonight.
The weather was lovely. Not a cloud in the sky, temps in the low 20s centigrade. Short drive up to the plateau (about 4 kilometes) from our house.
I had been practicing a bit in the living room, so I broke it all down and popped it into the car. We parked about as near as humanly possible and carted things into the pedestrian part of the town.
Set up, plugged in. Got zero sound from my favourite amp, an Ampeg Jet II. Nada. Rien. Zip. Zilch. Niente. Super weird. It had been working perfectly less than 2 hours and five kilometers ago!
Skipped the pedal board, went straing to the amp. Nothing. Swapped cables. Nothing. Shook the amp to hear the reveb tank: Loud and clear. hunh. (problem between the pre-amp and the power amp sections?)
The host , Niko – great guy- runs a funky t-shirt shop- grabbed a little 5w Gorilla for me. Got that up and running and 1 minute in, it just died. Power dropped by half and got all fuzzy.
Plugged into the small PA we had, which worked as long as I didn’t use the pedal board. Played half the hour-long set like that.
Meanwhile, Claudine had gone home and come back with another amp (thank god I have two that function!), so I ran into that directly, and it worked. Finished the gig that way.
Got home a bit later and tested everything.
– The pedal board was weird. Everthing lit up properly, nice strong indicator lights, but the volume was cut my more than half. Unplugged everything (power and audio connections –even pulled everthing off the board), and ran each pedal one by one through a known good power source. They all worked as expected. Then went back tp the pedal board and tested each power output with a single pedal. Outputs 3 and 4 don’t work, but I knew that.
Interatingly outputs 2, 5, 6, 7, and 8 all did this little hesitation before coming fully online. But in the end they all worked. So I plugged everything back in and fired them all up. Everything is now just fine.
– Tested the Ampeg, hoping it would miraculously come back too. No such luck. But at least the symptoms haven’t changed. It still has zero input.
Result: I blew to amps and a pedal board power supply tonight. And still managed to get people to sing for me in the street!
Daniel
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OK. Slept well last night. Woke up, went for a walk with Claudine, took the kids to Aikido in the next village where I worked on exams for tomorrow, and came back. Been thinking about the Ampeg the whole time.
I decided that the nature of the issue -being sudden and total- indicated a physical failure of some sort… a complete disconnection of the signal somewhere. Since the amp was not bounced around at all between 3pm and 5pm, it had to be something more fragile.
So I this afternoon I opened the amp and had a look around. Nothing visual, nothing that moves to much. Jacks are still solid, tubes are tightly connected, no burn marks anywhere.
Back in March I replaced a preamp tube (a 12AT7 or 12AX7) for another type of tube that would reduce the volume of the amp by a little without killing the trem circuit.
It looked fine. But I pulled it and replaced it with the original tube.
Et voilà! Fully functioning amp! Yay me! Boo whoever made this tube!
OK, now I just need to feel confident about my pedal board’s power supply! 😉
Daniel
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What an adventure, Daniel. I’ve done that with 12AT7’s vs 12AX7’s and run into the same issue, swapped them out, and the amp worked great. The internet knowledge base on this isn’t the best I think the older amps, especially Ampeg’s can have an attitude when confronted with a slightly weak tube. Glad it’s all back running, keep us posted as the week progresses, first hand experience is gold.
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The tube that failed is a 12DW7. I wish it still worked. It reduced the amount of power in the preamp by about 6 or 7 dB, which made the single volume knob abit less touchy below 2 and a lot more useful beetween 3 and 5. the tone was also a bit smoother. I’ll send it back and try again.
Another gig last night, and another scare. This time the replacement amp, my Marshall MG30CFX, from the week before failed to make noise. Here’s me swapping cables, taking the pedal board out of the loop, thinking about plugging my electro-magnetic pickups into the PA (again)… When my 12 yo daughter says, “should you try turning up this knob?” It was the Master volume. <heavy sigh with eyeroll>
The pedal board was perfect. So I think what happened last week was that two unused power leads touched or grounded. All leads are now taped securely with electrical tape to avoid this in the future.
[Now those of you who play electrics are probably wondering why I bother with the MG series by Marshall. And while I agree that these amps are rubbish ; they’re made for players whose guitars will never leave their bedrooms/man caves. Players who play at guitar rather than play guitar. This may be a valuable market, but oh these amps!
I like my MG30CFX several reasons.
- The memory function. I can set the everything except reverb and master volume in memory and take the amp to a gig. I won’t have to reset everything when I get to the venue.
- The clean channel is actually a good match for a 5 string mandolin. The 30w with a 10″ speaker in a closed cabinet gives a lot of bass.
- The MP3 player input turns this amp into a powered speaker. I can run my old Line6 POD 2.0 as an amp and get pretty good tone that way. (Though it’s too much trouble ususally.)
- The “carbon fibre” covering with silver/grey control panel looks pretty cool. I don’t know why Marshall hasn’t used it on other models and series.
- They’re less than $200. This makes them cheap and easily replaceable.
Another gig next week. Same set up. We’ll see if I can manage to avoid near panic as well as avoiding technical issues. 😉
Daniel
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