Just wanted to thank you for sharing all your knowledge here and posting so many videos. I appreciate all the theory videos that are available on CZcams, but nothing beats having lots of practical examples to really see how the rubber hits the road. Again - Thank you!
My experience with a lot of those small alpha pots is that the rivet connections to the carbon traces in the two exterior connections of the pot become loose as a result of them being the only support for the board. Just gingerly squeezing them with small side cutters will permanently resolve that issue. I've done this many times with no recalls.
Still catching up on your videos, Lyle. Loving the library of your work. As a sober beginner, at the tender age of 69, in comprehending amp circuits, it is a pleasure to have your skills and opinions to study. Thank you.
I got one of these a couple years ago for tinkering purposes. Mine ended up fairly close to the dirty channel of a Bogner Shiva after a couple component value changes in the preamp, so it pretty much sounds like Alice in Chains in a box. :)
I've owned several Jet City amps, and commonly have had to replace dead pots. Some of their older 20 watt amps had thinner boards and weaker traces, but at some point they did make them better. Really good modding platforms too, if anyone is into that. Pretty much a JCM800 type circuit.
I have a JCA 20 opened up on my bench that I bought for song due to crappy 12AX's. I use it for experimenting and testing. I agree with you it is fairly well made and easily serviceable, the traces are heavy and trannies and sockets hold up to abuse. My reverb version can use 12AX's in all 5 preamp positions, and it sounds pretty damn good for a total $200 investment. Sorry I can't help with the quasi jewel light...
I’ve had this a pot issue with an Egnator Rebel 20 in 00’s. My first amp and biggest nightmare I’ve had with any piece of gear…acoustic or electric. They either don’t ever get fixed or they are in a market that doesn’t get represented in CZcams amp community. It was a Guitar Center mistake of mine and I knew nothing about amps. Not it’s only issue. It was at a time when opinions were not very well informed; old school shops had already been sacrificed in favor of cheap and loud. In fairness, maybe I bought a lemon but the tech I brought it to said “no”….not worth fixing-get out while you can. This new era were living in hadn’t really got started and I knew no difference. My second amp was as Kalamazoo Model One and it was miles ahead of that gives a reference. I still play it to this day and I wouldn’t give the Rebel 20 away. That’s one of the problems when you live in the rural world. Play as many amps as you can, and if you love playing electric, find someone you trust that can steer you right! This channel has been a great informer, without emotional attachment. Just the facts, the good, the bad and the ugly!
I have the head, Jet City JCA2OH. I think that's this one? It works just fine but I'm told it will sound even better with some mods and maybe an FX loop? I'd rather troubleshoot any existing issues before modding, but do you think it's worth modifications? FX loop?
Hi mate thank you for this great video. Regarding the lamp and the original being a LED lamp. Mine was also dead and not working on my JCA20H. I have just however brought a real lamp with bulb. With regards to voltage etc, is it a straight swap from the led one to the real fender one with bulb or is there more to the change over?. Would appreciate your advice.
I’d love to here your review of my amps! Especially my Jackson Ampworks. I was told by another amp guy that it’s just a pain in the ass build that does not lend itself to easy repairs. I actually sent it to him because I would get this loud ringing and had no idea where it was coming from. Replaced the ALL tubes to to have a fresh start… and it’s only happened once that’s why I sent it to him. He couldn’t replicate the issue and said from what he could tell all caps and resistors looked healthy 🤷♂️. I wanted the backlit logo to be repaired but he said it was basically too complicated and didn’t know how to go about it
@@PsionicAudio I’ve never met Brad but he sure seems swell! He’s since moved on to pedals tho and it’s hard as hell to get any communication with his company about amps 😔 I really do enjoy my Fullerton though😎
ALMOST bought a Blackstar Jared James Nichols head .....until I saw a vid from a tech that its computer chip controlled reverb and surface mount tech with computer ribbons connecting EVERYTHING pretty much....so look I probably won't go that way!!!!
Is that a reference to " Swee -ee-ee- ee eet, Sweet City Woman"?. Thanks for that ---- not! Now I'm gonna hear that damn guitar lick in my head for a day and a half!
@@Shiloh7377 , not a metal fan and therefore not really familiar with queensryche, that's why I didn't get your musical reference. I also wish I'd never heard that damn pop song which I referenced to; some earworms never go away!
Not sure I understand why you would worry about seeing a "raggedy" hole for the jewel over the pilot-light LED; wouldn't the ferrule of the jewel cover the edges of the hole?
Wow, quite a lot of sketchy solder joints on this one. All the sockets were never cleaned of flux, and I could not tell if the big filter cap was leaking, or if it was flux / glue residue. Obviously you would have changed the cap if it had leaked. Interesting problem with that treble potentiometer. Thanks.
I bought one of these used, and it was a little to gainy for me, I bought a new "set" of tubes from a reputable tube seller for this amp. When I put in the outside EL84, the socket felt like something was wrong. When I took off standby, that tube started red plating. I tried back to the tubes that were in it, and it still felt wrong in that socket. It worked momentarily, then started crackling and red plated again. I also have the Vintage version that came out later( I bought new on clearance for 199), and retubed that with some Gold Lion tubes, and that amp works and sounds very good. Should I sell the damaged amp as is? Should I part it out? I paid 175 for it used but really didn't like the sound near as much as the vintage version. The transformers are probably worth more than the whole head. What do think it's worth as is?
Jet City might buy it back if you contact them. If you ship it to them they will replace the board for $100 with one of their new custom boards. Check out their sight.
I had one of those and I think it is a quite bad sounding amp, so even if bought second hand it is not a good amp, I paid what would would be about $180. Very thin and lifeless.
I felt that way about mine, I found that it had a severely mismatched set of Shugang EL84s. Replacing the tubes with a new matched pair and setting the bias properly really helped!
Just wanted to thank you for sharing all your knowledge here and posting so many videos. I appreciate all the theory videos that are available on CZcams, but nothing beats having lots of practical examples to really see how the rubber hits the road.
Again - Thank you!
My experience with a lot of those small alpha pots is that the rivet connections to the carbon traces in the two exterior connections of the pot become loose as a result of them being the only support for the board.
Just gingerly squeezing them with small side cutters will permanently resolve that issue. I've done this many times with no recalls.
Still catching up on your videos, Lyle. Loving the library of your work. As a sober beginner, at the tender age of 69, in comprehending amp circuits, it is a pleasure to have your skills and opinions to study. Thank you.
I love these little amps. So much value for money for a tinkerer.
Hey nice to see you here Brad + glad you like those Jet City amps as well.
I got one of these a couple years ago for tinkering purposes. Mine ended up fairly close to the dirty channel of a Bogner Shiva after a couple component value changes in the preamp, so it pretty much sounds like Alice in Chains in a box. :)
I've owned several Jet City amps, and commonly have had to replace dead pots. Some of their older 20 watt amps had thinner boards and weaker traces, but at some point they did make them better. Really good modding platforms too, if anyone is into that. Pretty much a JCM800 type circuit.
Wow that Bias was nuts and you could see the heat damage to the board from all the tubes. Amazing that it didnt blow up.
Yeah I was just thinking that as I was watching. Crazy the bias was that high, but as he said someone must have messed with the pot.
Great video and very instructive as usual. Keep up the excellent work.
I have a JCA 20 opened up on my bench that I bought for song due to crappy 12AX's. I use it for experimenting and testing. I agree with you it is fairly well made and easily serviceable, the traces are heavy and trannies and sockets hold up to abuse. My reverb version can use 12AX's in all 5 preamp positions, and it sounds pretty damn good for a total $200 investment. Sorry I can't help with the quasi jewel light...
A bit of a design oversight to give a range on the bias that will let it go over 110% of rated dissipation . A large range should be to the cold side.
That is because they use the most affordable parts to source and sometime the percentage of range is huge.
I’ve had this a pot issue with an Egnator Rebel 20 in 00’s. My first amp and biggest nightmare I’ve had with any piece of gear…acoustic or electric. They either don’t ever get fixed or they are in a market that doesn’t get represented in CZcams amp community. It was a Guitar Center mistake of mine and I knew nothing about amps. Not it’s only issue. It was at a time when opinions were not very well informed; old school shops had already been sacrificed in favor of cheap and loud. In fairness, maybe I bought a lemon but the tech I brought it to said “no”….not worth fixing-get out while you can. This new era were living in hadn’t really got started and I knew no difference. My second amp was as Kalamazoo Model One and it was miles ahead of that gives a reference. I still play it to this day and I wouldn’t give the Rebel 20 away. That’s one of the problems when you live in the rural world. Play as many amps as you can, and if you love playing electric, find someone you trust that can steer you right!
This channel has been a great informer, without emotional attachment. Just the facts, the good, the bad and the ugly!
Fascinating. Thanks. The circuit board does look well made.
I have the head, Jet City JCA2OH. I think that's this one?
It works just fine but I'm told it will sound even better with some mods and maybe an FX loop?
I'd rather troubleshoot any existing issues before modding, but do you think it's worth modifications? FX loop?
That PCB looks likes something that I etched in a fish tank in the 1970s
“Fish tank “?
I like them like that. Actual thick solder runs.
Hey PA, thank you for sharing this with us - question:
How hard would it be, in your opinion, to add a FX loop into this small monster?
Effects loops are fairly easily added on these. If you work on your own amp work there is a diy fx loop kit available from Epic Amplification.
amazing sleuth-ery!!!!!! so damn kool!!!!
Hi mate thank you for this great video. Regarding the lamp and the original being a LED lamp. Mine was also dead and not working on my JCA20H. I have just however brought a real lamp with bulb. With regards to voltage etc, is it a straight swap from the led one to the real fender one with bulb or is there more to the change over?. Would appreciate your advice.
My amplifier tech changed the on off jewel lamp to a Fender
I'm curious to know if you've ever had any Wangs amps come your way?
I’d love to here your review of my amps! Especially my Jackson Ampworks. I was told by another amp guy that it’s just a pain in the ass build that does not lend itself to easy repairs. I actually sent it to him because I would get this loud ringing and had no idea where it was coming from. Replaced the ALL tubes to to have a fresh start… and it’s only happened once that’s why I sent it to him. He couldn’t replicate the issue and said from what he could tell all caps and resistors looked healthy 🤷♂️. I wanted the backlit logo to be repaired but he said it was basically too complicated and didn’t know how to go about it
Jackson Ampworks are usually great. I used to know the guy who made them but it was mumble years ago.
@@PsionicAudio I’ve never met Brad but he sure seems swell! He’s since moved on to pedals tho and it’s hard as hell to get any communication with his company about amps 😔 I really do enjoy my Fullerton though😎
I really liked Jet City. It’s a shame they’re not around anymore.
Yes they are, making custom optioned amps at a low price
I recently purchased a 20w Brown Iris amp frm them. They were only out of business a short time around 2021 before going the custom rout.
ALMOST bought a Blackstar Jared James Nichols head .....until I saw a vid from a tech that its computer chip controlled reverb and surface mount tech with computer ribbons connecting EVERYTHING pretty much....so look I probably won't go that way!!!!
The Fender Concert Rivera-Era fender amp have you found them as good as they claim?
Board looks older than snot.. miss that style.. you could snap a board in half and still be able to bridge the links and make her chooch again…
🎵🎵Jet City Women.....
Is that a reference to " Swee -ee-ee- ee eet, Sweet City Woman"?. Thanks for that ---- not! Now I'm gonna hear that damn guitar lick in my head for a day and a half!
@@goodun2974 lol, I was thinking jet city women by queensryche....
@@Shiloh7377 , not a metal fan and therefore not really familiar with queensryche, that's why I didn't get your musical reference. I also wish I'd never heard that damn pop song which I referenced to; some earworms never go away!
@@goodun2974 I've never heard the song you referenced, I'll have to look into it.
@@Shiloh7377 , it's a schlocky piece of 70's pop music. I don't remember who sang it.
I WISH I could find one with the Friedman BE and or mercury mod also...for 400/450 I would buy it in a second!!!!
Epic Mods, pretty much every mod is under $100, the HBE is like 75 maybe
Not sure I understand why you would worry about seeing a "raggedy" hole for the jewel over the pilot-light LED; wouldn't the ferrule of the jewel cover the edges of the hole?
Not if isn't flush.
A wonder the glass wasn’t hot enough and the vacuum pulled a hole in it.
I like your content, but it makes me nervous to buy any amp. What is good out there for less than a grand?
A silverface fender.
Sounded pretty decent. It has a master volume?
Yes.
Off subject, which desoldering wick do you recommend? I use Kester solder.
Tech-Spray No Clean #4. I use Kester too.
Wow, quite a lot of sketchy solder joints on this one. All the sockets were never cleaned of flux, and I could not tell if the big filter cap was leaking, or if it was flux / glue residue. Obviously you would have changed the cap if it had leaked. Interesting problem with that treble potentiometer. Thanks.
That's glue on the filter caps.
This pcb seems like home made, isn't?
No, and it's quite good.
I bought one of these used, and it was a little to gainy for me, I bought a new "set" of tubes from a reputable tube seller for this amp. When I put in the outside EL84, the socket felt like something was wrong. When I took off standby, that tube started red plating. I tried back to the tubes that were in it, and it still felt wrong in that socket. It worked momentarily, then started crackling and red plated again. I also have the Vintage version that came out later( I bought new on clearance for 199), and retubed that with some Gold Lion tubes, and that amp works and sounds very good. Should I sell the damaged amp as is? Should I part it out? I paid 175 for it used but really didn't like the sound near as much as the vintage version. The transformers are probably worth more than the whole head. What do think it's worth as is?
I'm sure that would be an easy fix. But I have no idea what a selling price for it would be.
Jet City might buy it back if you contact them. If you ship it to them they will replace the board for $100 with one of their new custom boards. Check out their sight.
How much you ask for one hour of labor?
$100
more fuzz less buzz
I had one of those and I think it is a quite bad sounding amp, so even if bought second hand it is not a good amp, I paid what would would be about $180. Very thin and lifeless.
I felt that way about mine, I found that it had a severely mismatched set of Shugang EL84s. Replacing the tubes with a new matched pair and setting the bias properly really helped!
That PCB is fried. Will be nothing but problematic from now til the end of time.
That is simply not true, he would have said that ion the video. Not at all, looking at the video.