My amp suddenly started crackling and then shorting out after I moved it with my car to a gig. I guess it was lying face up instead of upright for a bit. Tried changing out tubes but the same problem persisted, and a huge crackle happened when I touched the tubes with a chop stick. I just removed the tube sockets to look under them and found a tiny piece of foil. Put it back together and now it works perfect. Thank you!
Haha, Brad you are not holding back today! Love it. These manufacturers screwing us over by building crappy products that blow themselves up in a year or two and overcharging us for them has to stop.
Fender owns a majority in GT stock! More tubes blown = more tubes sold = more $$$. I don't really know; but, it pisses me off. I have this amp and a Blues Junior and it toke some time, and expense, to straighten them out. Both sound great now.
One of my power tubes blew up after a couple of years, in my adorable ProJR IV. My tech told it was way tooooo hot biased… changed it, rebias, now it works great!
It's the same old song. Amp manufacturers want to sell amps. They run them hot giving the sound of crunch, and the store makes the sale. Then, amp technicians get the amp in for some jangle in the jeans. I would tell amp manufacturers to make the bias hotter. Then tube manufacturers can sell more tubes too. Cheers 😀
My comment was totally sarcastic, but Fender is getting a lot of heat over their amps. Cheap, cheap, cheap. I've always been taught, if you're going to do something, then be the best you can be. Leo, was really cheap, but he had reliable parts to work with that stood the test of time, until he sold the company.
I don’t get the EL84 deal either - you could cook food with those valves - glad to hear you point that out - coming from an amp technician as yourself - I had a Marshall with a quad of them in it and the control panel got so hot you could iron your pants with it - I’m not exaggerating - Cheers
Aloha Ranty! Interested in knowing more. I bought one new in '96. Faceplate is also rusted. 1 of 2 amps I should not own. Got a Marshall JTM 60. Paid $50 appears to have bad OT. Would like to drop a new chassis. Maybe a 1987 or Tweed deluxe
@@BradsGuitarGarage oh what can be done too improve my Pro Jr. At some point put together amp for the Marshall combo cab. Any suggestions? Usually play blues based rock.
Check out my Pro Jr vids, mate. I think Lyle has some too. If I don't mention it in the video, also drop C1 (first stage bypass cap) value to somewhere around 1 to 5uf to pull the bass response to what the output stage and speaker in small cab can handle without getting farty. Make sure you pull the bias back down to about 50-60% if the plate voltage can be kept under about 340-350V. And raise the value of the screen grid resistors up to 1-1.5k 2w. Perhaps a Switchcraft 11 jack install too.
Depends where it is in the circuit. You can also read the schematic and determine the expected value in circuit if it is affected by parallel resistances etc.
Wonder if we could get some of the Gibson haters on here to transfer their angst to Fender? I'm sure they don't know any more about one than the other. Maybe they could become "useful" idiots. Just a thought...
i have loose knobs on my pro jr (tweed) they wobble from side to side quite a bit. Any videos on how to repair or replace these? they dont look like a typical.potentiometer.
On the Pro and Blues Juniors, the knobs can’t be replaced. The pot shaft and knob are one piece. Idk if that’s what a true for versions 3 and 4, but on V1 and 2 you can’t replace them. Those amps are very cheaply made. If your amp has one piece knob and pot, you’ll have to have the pcb and pots replaced and it’s not worth the investment. I had a first run US BJr and when I discovered these problems, I sold it and bought a better amp.
Although I haven't had one on the bench just yet, I'm hearing off reliable sources that the BJ4's with cathode bias are still biased in the 130+% range and with excessive plate voltage, so don't hold your breath for a reliable amp from Fender these days, mate.
@@BradsGuitarGarage I wanted to buy one new.. but it seems ill have to wait for some used one to get it cooler without loosing warranty.. Thank You for the information :)
Real amp designers get to work with BIG BOTTLES! Boss wants me to do a little wimp amp Im a gonna KILL those little valves! 420VDC and 30W and NO SGRs !!
Excelsior? It's one of the pawn shop series from about ten years ago. It's two cathode-biased 6V6s into a 15" speaker. Has volume and speed control for trem. It's got a couple of 250 Ohm resistors in the power supply to sound like a valve recto. It's biased too hot (surprise) but it can take it better cuz of the cathode bias. Best of all: all the valve bases,. pots & switches are mounted on the chassis. The input jacks are mounted on their own little PCB, which can be replaced with proper jacks when they fail.
Yes, if one of them has been neglected or abused, you may be up for as much as $1k to get it solid, but it will then be solid for multiple decades. I was referring to their current production offerings.
@@BradsGuitarGarage How do the tweed Bassman reissues stand up? I don't see them turning up in these videos by guys like you or Lyle. I presume they'd need the nasty IC brand filters replaced after 3-5 years, but what else goes pear shaped in those?
Eye (can) make ammo that is the most accurate for any firearm, that i can do. Fix anything electrical, beyond r/r batteries? nope. Every amp repair technician on EweToob says the same re Fender economy tube amps! Bless you✝️
I regret I have but one like to give for this video…
S'okay Lyle, I gave another for you 🙂
“Read the data sheets and stick to them you dickheads”. Greatest RUclips moment in a long time, thank you. 🤣
Because they sound so darned good while they are melting 🤣
I am glad I am not the only one. "Every EL84 amp on the planet is biased way too fucking hot". My experience exactly and not just Fender.
My amp suddenly started crackling and then shorting out after I moved it with my car to a gig. I guess it was lying face up instead of upright for a bit. Tried changing out tubes but the same problem persisted, and a huge crackle happened when I touched the tubes with a chop stick. I just removed the tube sockets to look under them and found a tiny piece of foil. Put it back together and now it works perfect. Thank you!
Good to hear you sorted it, mate!
Feel content that the tubes were probably almost gone with the stock circuit anyway.
Haha, Brad you are not holding back today! Love it. These manufacturers screwing us over by building crappy products that blow themselves up in a year or two and overcharging us for them has to stop.
Fender owns a majority in GT stock! More tubes blown = more tubes sold = more $$$. I don't really know; but, it pisses me off. I have this amp and a Blues Junior and it toke some time, and expense, to straighten them out. Both sound great now.
One of my power tubes blew up after a couple of years, in my adorable ProJR IV. My tech told it was way tooooo hot biased… changed it, rebias, now it works great!
I've thought about hunting out one of these second hand & cheap and sticking it in a bigger cab with a 12" or a couple of 10"s.
It's the same old song. Amp manufacturers want to sell amps. They run them hot giving the sound of crunch, and the store makes the sale. Then, amp technicians get the amp in for some jangle in the jeans. I would tell amp manufacturers to make the bias hotter. Then tube manufacturers can sell more tubes too. Cheers 😀
Unfortunately I actually want my customers to get value for money. Call me crazy.
My comment was totally sarcastic, but Fender is getting a lot of heat over their amps. Cheap, cheap, cheap. I've always been taught, if you're going to do something, then be the best you can be. Leo, was really cheap, but he had reliable parts to work with that stood the test of time, until he sold the company.
I don’t get the EL84 deal either - you could cook food with those valves - glad to hear you point that out - coming from an amp technician as yourself - I had a Marshall with a quad of them in it and the control panel got so hot you could iron your pants with it - I’m not exaggerating - Cheers
I think everyone just directly copies the original AC30 output stage, regardless of the valves being much more resilient back then.
Nice fix, pity Fender doesn't address those silly defects...Hey Ho..Interesting tech info for quick checking circuit..Ed..uk..😀
Aloha Ranty! Interested in knowing more. I bought one new in '96. Faceplate is also rusted. 1 of 2 amps I should not own. Got a Marshall JTM 60. Paid $50 appears to have bad OT. Would like to drop a new chassis. Maybe a 1987 or Tweed deluxe
Aloha, Victor! What more do you want to know?
I didn't see a question in there.
@@BradsGuitarGarage oh what can be done too improve my Pro Jr. At some point put together amp for the Marshall combo cab. Any suggestions? Usually play blues based rock.
Check out my Pro Jr vids, mate.
I think Lyle has some too.
If I don't mention it in the video, also drop C1 (first stage bypass cap) value to somewhere around 1 to 5uf to pull the bass response to what the output stage and speaker in small cab can handle without getting farty.
Make sure you pull the bias back down to about 50-60% if the plate voltage can be kept under about 340-350V.
And raise the value of the screen grid resistors up to 1-1.5k 2w.
Perhaps a Switchcraft 11 jack install too.
@@BradsGuitarGarage Mahalo will check video
thought you need to disconnect one leg of the resistor when measuring a resistor in a circuit?
Depends where it is in the circuit.
You can also read the schematic and determine the expected value in circuit if it is affected by parallel resistances etc.
@@BradsGuitarGarage thanks love the vids man
Wonder if we could get some of the Gibson haters on here to transfer their angst to Fender? I'm sure they don't know any more about one than the other. Maybe they could become "useful" idiots. Just a thought...
i have loose knobs on my pro jr (tweed) they wobble from side to side quite a bit. Any videos on how to repair or replace these? they dont look like a typical.potentiometer.
On the Pro and Blues Juniors, the knobs can’t be replaced. The pot shaft and knob are one piece. Idk if that’s what a true for versions 3 and 4, but on V1 and 2 you can’t replace them. Those amps are very cheaply made. If your amp has one piece knob and pot, you’ll have to have the pcb and pots replaced and it’s not worth the investment. I had a first run US BJr and when I discovered these problems, I sold it and bought a better amp.
No need to roast that amp,mate! It'll roast it's self out of shame.😒
someone has been in that amp, but you blame in on QC? these amps do blow up, but they sound great :)
Someone who has been in the amp didn't bias it at 130% in a fixed bias configuration.
Fender did that all on their own.
Do you think pro juniors need a power and output transformer change?
Not unless they've failed.
That's the least of the problems with these.
Because they are in cahoots with the tube manufacturers……..blow the EL84’s ….make more money
Anyone know if Pro Jr. IV has colder bias like bj4 has?
Although I haven't had one on the bench just yet, I'm hearing off reliable sources that the BJ4's with cathode bias are still biased in the 130+% range and with excessive plate voltage, so don't hold your breath for a reliable amp from Fender these days, mate.
@@BradsGuitarGarage I wanted to buy one new.. but it seems ill have to wait for some used one to get it cooler without loosing warranty.. Thank You for the information :)
Real amp designers get to work with BIG BOTTLES! Boss wants me to do a little wimp amp Im a gonna KILL those little valves! 420VDC and 30W and NO SGRs !!
Lol is there a good fender amp?
Excelsior? It's one of the pawn shop series from about ten years ago. It's two cathode-biased 6V6s into a 15" speaker. Has volume and speed control for trem. It's got a couple of 250 Ohm resistors in the power supply to sound like a valve recto. It's biased too hot (surprise) but it can take it better cuz of the cathode bias. Best of all: all the valve bases,. pots & switches are mounted on the chassis. The input jacks are mounted on their own little PCB, which can be replaced with proper jacks when they fail.
Stock without needing anything done to it? No.
Many that can be upgraded and modified to give a long great sounding life, however.
The vintage stuff...
Yes, if one of them has been neglected or abused, you may be up for as much as $1k to get it solid, but it will then be solid for multiple decades. I was referring to their current production offerings.
@@BradsGuitarGarage How do the tweed Bassman reissues stand up? I don't see them turning up in these videos by guys like you or Lyle. I presume they'd need the nasty IC brand filters replaced after 3-5 years, but what else goes pear shaped in those?
This man needs a hug.
Eye (can) make ammo that is the most accurate for any firearm, that i can do. Fix anything electrical, beyond r/r batteries? nope. Every amp repair technician on EweToob says the same re Fender economy tube amps! Bless you✝️