@@PsionicAudio You are a true amp tech guru, and through this medium you'll be perpetually educating while saving amps, cash and minds worldwide. Greetings from Scotland my brother's, hope you had a good festive season and thank you.
Nice work. I appreciate your getting to the point right away. I see your videos as mini crash courses in “here’s what I learned this could be” and the troubleshooting to get to the bottom of it. Super helpful for all of us who are just working on our own amps who don’t have the years of experience. Keep ‘em coming!
Its cool that you did a video on the 68’ Custom series, as I just got a 68’ Custom Pro Reverb // definitely great to know more about how these are put together 👏
Thanks! I have a stereo amp that started doing this in the middle of the night. It only made sense that it was the filter cap (both channels), but I've been procrastinating trying to fix it. I think I'll give it a shot now since it sounds almost exactly like yours (I don't have any test equipment for something like this).
One time some years ago I foolishly forgot to discharge the filter caps. About 450V went across my chest from one arm to the other. It knocked me off my feet and REALLY hurt. I am amazed that I did not go into cardiac arrest. I don't make that mistake any more. lol
Isn't that why they say you won't do that more than once? 😬 I've only been inside of my amps once, (though I may take on a project or two eventually) but the FIRST thing I learned was how to safely discharge and check caps. Side note: a friend of mine has a solid-state power amp for his stereo that takes almost a full minute to fully fade into silence. Yikes!
I will just put it lightly, a lot of people dont use their brains anymore...your a tech, and a great one at that, as you said, it is your job! Edit: i had one of these custom deluxe for a very short time, had the loudest noisefloor i heared yet, must have been bad from the beginning, needles to say i returned it as it was brand new.
what is the procedure to power up new filter caps? all I can find is to gradually increase volts with a variac. do you leave all tubes in the amp? pull all the tubes? start at what voltage? define slowing bring up voltage..... tks David
Dear Doctor Lyle. In the ongoing saga of making my 2020 ‘68 CDR actually useable I discovered it doesn’t have the 18k resistor, which means I didn’t get the legendary “Bassman tone stack.” Should I sue or consider myself lucky? 🤣 (Love your videos!)
This may be a dumb question as I am fairly new to this, so apologies in advance,….but at 6:38 when you are testing the smaller capacitors, what are you measuring and what setting do you have your multimeter set to?? I have a “real tube” pre amp overdrive pedal from the 90s and it’s giving me problems and has a bad hum/buzz when in bypass and even worse when kicked into overdrive and I’m starting to think maybe it’s the capacitors that are bad in it because the tube looks fine. Thank you in advance
I have found the DER EE de-500 lcr meter rather helpful dealing with Caps able to test esr at 100,120,1k,10k,100k as well as inductance . As the boy over the pond say " A fine bit of kit" . Nice video as always keep up the fine work . So rather than insert the 18k resistor and cut the track could you not just up the in circuit resistor by 18k or did I miss some thing there ?
@@PsionicAudio The only thing comes to mind is that if the bass is turned all the way down does it cause a problem with the circuit misbehaving ? If not then it is the true definition of WTF you wasted production time with this mod.
@@PsionicAudio I test before using in a power supply . the difference at 10k and 100k vs 1 k can be very large . photoflash caps are very good up to 100k stay below the 330 volt use . Knocks out a bit of the am rf for me.
What if new filter caps don’t fix the buzz? I have a 78 ultralinear twin that I cannot stop the buzzing. The bias drifts no matter what I do, I have changed caps, pots, and resistors, The only thing I have not changed is the output transformer. What am I missing?
Hey! Thanks for the video, I have a simular problem with my tweed amp, made a little video about it, maybe you would chevk it out and see if it's probably the same issue?
Yes, of course they do. The capacitors in a solid-state amp will be rated for lower voltage than those in a tube amp (perhaps 100 volts at most, versus 450-500 volts in a tube amp), but all audio amplifiers require capacitors. There are other things that can cause buzzing besides bad filter caps, however, including intermittent or disconnected grounds, broken solder connections, and shorted diodes or transistors.
I'm guessing that being an amp tech and getting to service really old amps from the '40s, '50s & '60s that in some cases were built by people who had previously assembled mil-spec equipment during World War II, current production amps must look especially cheap in comparison, LOL. In one of his videos Uncle Doug serviced a Gibson amp from 1946, the innards of which looked amazing, like something found in a B-17 Flying Fortress, all the wires neatly twisted and routed, etc.
For me being a retired Electroincs Design Eng, I find that Fender has been using the least reliable brands of components, especially for the price they charge for their products. For me, Even back in the 1970's I refused to but a "FENDER" strat. I bought the Ibanez Silver Series instead. that guitar prove to take the road abuse, sound great, till this day. And yes, It's still one of my favor guitars. I reffuse to sell it.
The essence of debugging is to find faults. Those who cannot do it will be destroyed on the lathe of heaven. (Chuang Tzu as mistranslated by Ursula K LeGuin)
This is literally the problem I'm having with my 67/68 Twin Reverb now. It's been at the tech 3 months and he's getting help with filter cap. I'd like to pick it up and drive it to you. Interested in fixing it? I'd be grateful. It's a vintage one. Drip Edge
I saw you say you were backed up like 9 months or something on your live stream. But when I saw this post today. I was like damn that sounds like mine and the tech told me he's never done a cap job. I love that old amp
@@weschilton I agree. He's one of only a couple amp techs in my area. And his mentor works at another local music store and is supposed to be doing the cap job and showing him. But between it being 3 months and this no cap job experience I been trying to find someone else. Tennessee is only 1 state away
I don’t know the year but it’s fairly recent. Good filter caps should last 10-15 years. These ICs seem to start to go after about 3. Not all of them, of course. But an awful lot.
@@PsionicAudio I appreciate the response, mine is a 2018 but still seems to be holding up. May just do em preventatively. As a total nerd, I absolutely love your content. Thank you!
After watching a few of these videos, Im not buying a Fender amp anytime soon. Maybe its an overreaction, but come on Fender. American quality used to mean something.
Few things are more annoying to a service tech than an amp that appears to operate correctly and doesn't exhibit the fault that the customer says it has; or perhaps the fault comes and goes randomly, and the device doesn't malfunction often enough or for a sufficiently long period of time that you can troubleshoot it.
Видеоклипы
Don't let the trolls bother you so much. You are a top tech, ignore them.
They don’t really bother me. I find it a little absurd.
@@PsionicAudio Yeah, it's just simple ignorance!
@@PsionicAudio You are a true amp tech guru, and through this medium you'll be perpetually educating while saving amps, cash and minds worldwide. Greetings from Scotland my brother's, hope you had a good festive season and thank you.
Lyle I do not have the first clue what you are doing but I love watching these videos, thank you for making them.
Nice work. I appreciate your getting to the point right away. I see your videos as mini crash courses in “here’s what I learned this could be” and the troubleshooting to get to the bottom of it. Super helpful for all of us who are just working on our own amps who don’t have the years of experience. Keep ‘em coming!
Its cool that you did a video on the 68’ Custom series, as I just got a 68’ Custom Pro Reverb // definitely great to know more about how these are put together 👏
You are an amazing tech, nice work sir! 🤘
Great example of troubleshooting, Lyle.
Thanks! I have a stereo amp that started doing this in the middle of the night. It only made sense that it was the filter cap (both channels), but I've been procrastinating trying to fix it. I think I'll give it a shot now since it sounds almost exactly like yours (I don't have any test equipment for something like this).
2:36 Excellent point, beautifully presented 🙂
Lyle. Thanks great video
Always the sound one hears in those old films of Frankenstein's monster as his electrodes are connected...😉
😎👍
Haha, good catch!
One time some years ago I foolishly forgot to discharge the filter caps. About 450V went across my chest from one arm to the other. It knocked me off my feet and REALLY hurt. I am amazed that I did not go into cardiac arrest. I don't make that mistake any more. lol
Isn't that why they say you won't do that more than once? 😬 I've only been inside of my amps once, (though I may take on a project or two eventually) but the FIRST thing I learned was how to safely discharge and check caps. Side note: a friend of mine has a solid-state power amp for his stereo that takes almost a full minute to fully fade into silence. Yikes!
I will just put it lightly, a lot of people dont use their brains anymore...your a tech, and a great one at that, as you said, it is your job!
Edit: i had one of these custom deluxe for a very short time, had the loudest noisefloor i heared yet, must have been bad from the beginning,
needles to say i returned it as it was brand new.
Now do a video on a Pro Reverb whose on/off switch no longer turns off like mine does!
The Doctor is in.
what is the procedure to power up new filter caps? all I can find is to gradually increase volts with a variac. do you leave all tubes in the amp? pull all the tubes? start at what voltage? define slowing bring up voltage..... tks David
Where is video 2 of this ? Did the hum go away ?
Damn I wish I lived near you so I could get my amps worked on. I don't trust any amps anymore 😂
Dear Doctor Lyle. In the ongoing saga of making my 2020 ‘68 CDR actually useable I discovered it doesn’t have the 18k resistor, which means I didn’t get the legendary “Bassman tone stack.” Should I sue or consider myself lucky? 🤣 (Love your videos!)
This may be a dumb question as I am fairly new to this, so apologies in advance,….but at 6:38 when you are testing the smaller capacitors, what are you measuring and what setting do you have your multimeter set to?? I have a “real tube” pre amp overdrive pedal from the 90s and it’s giving me problems and has a bad hum/buzz when in bypass and even worse when kicked into overdrive and I’m starting to think maybe it’s the capacitors that are bad in it because the tube looks fine. Thank you in advance
I have found the DER EE de-500 lcr meter rather helpful dealing with Caps able to test esr at 100,120,1k,10k,100k as well as inductance . As the boy over the pond say " A fine bit of kit" . Nice video as always keep up the fine work . So rather than insert the 18k resistor and cut the track could you not just up the in circuit resistor by 18k or did I miss some thing there ?
The 18K is between the mids cap/6.8K junction and the pot. So you can’t turn the bass all the way down. It’s a fairly annoying useless “mod”.
@@PsionicAudio The only thing comes to mind is that if the bass is turned all the way down does it cause a problem with the circuit misbehaving ? If not then it is the true definition of WTF you wasted production time with this mod.
Yeah, it’s neither good nor implemented well.
I rarely test ESR on failing caps - time is money - but maybe I’ll test these for giggles.
@@PsionicAudio I test before using in a power supply . the difference at 10k and 100k vs 1 k can be very large . photoflash caps are very good up to 100k stay below the 330 volt use . Knocks out a bit of the am rf for me.
What if new filter caps don’t fix the buzz? I have a 78 ultralinear twin that I cannot stop the buzzing. The bias drifts no matter what I do, I have changed caps, pots, and resistors, The only thing I have not changed is the output transformer. What am I missing?
Hey! Thanks for the video, I have a simular problem with my tweed amp, made a little video about it, maybe you would chevk it out and see if it's probably the same issue?
See the comment on your video.
@@PsionicAudio thank you very much!
Hey Fender. How about making F&T filter caps stock? They may help sales.
Wouldn't it be nice if they cared enough...
@@weschilton The very reason I will never buy a modern Fender amp!
I have a peavey special 130, solid state amp that also buzzes. do SS
amps have capacitors also?
Yes, of course they do. The capacitors in a solid-state amp will be rated for lower voltage than those in a tube amp (perhaps 100 volts at most, versus 450-500 volts in a tube amp), but all audio amplifiers require capacitors. There are other things that can cause buzzing besides bad filter caps, however, including intermittent or disconnected grounds, broken solder connections, and shorted diodes or transistors.
Wish the amp model had a real master volume
I'm guessing that being an amp tech and getting to service really old amps from the '40s, '50s & '60s that in some cases were built by people who had previously assembled mil-spec equipment during World War II, current production amps must look especially cheap in comparison, LOL. In one of his videos Uncle Doug serviced a Gibson amp from 1946, the innards of which looked amazing, like something found in a B-17 Flying Fortress, all the wires neatly twisted and routed, etc.
For me being a retired Electroincs Design Eng, I find that Fender has been using the least reliable brands of components, especially for the price they charge for their products. For me, Even back in the 1970's I refused to but a "FENDER" strat. I bought the Ibanez Silver Series instead. that guitar prove to take the road abuse, sound great, till this day. And yes, It's still one of my favor guitars. I reffuse to sell it.
Dont worry about the haters Lyle. Tay Tay etc.
The essence of debugging is to find faults.
Those who cannot do it will be destroyed on the lathe of heaven.
(Chuang Tzu as mistranslated by Ursula K LeGuin)
This is literally the problem I'm having with my 67/68 Twin Reverb now. It's been at the tech 3 months and he's getting help with filter cap. I'd like to pick it up and drive it to you. Interested in fixing it? I'd be grateful. It's a vintage one. Drip Edge
I saw you say you were backed up like 9 months or something on your live stream. But when I saw this post today. I was like damn that sounds like mine and the tech told me he's never done a cap job. I love that old amp
@@g_and_kikos_homestudio A tech that has never done a cap job? That's no tech. Pick up your amp and don't let him touch it.
@@weschilton I agree. He's one of only a couple amp techs in my area. And his mentor works at another local music store and is supposed to be doing the cap job and showing him. But between it being 3 months and this no cap job experience I been trying to find someone else. Tennessee is only 1 state away
@@g_and_kikos_homestudiowould you happen to be in Georgia?
@@jakeabruzzino3910 no Indiana. I finally got the amp repaired also. Sounds great.
What year is this amp
What kind of lifespan can we expect ou to these caps? Or is it just random.
I don’t know the year but it’s fairly recent. Good filter caps should last 10-15 years. These ICs seem to start to go after about 3. Not all of them, of course. But an awful lot.
@@PsionicAudio I appreciate the response, mine is a 2018 but still seems to be holding up. May just do em preventatively. As a total nerd, I absolutely love your content. Thank you!
Yes, the sniff test. If it smells like fish, eat all you wish. If it smells like cologne, leave it alone!
After watching a few of these videos, Im not buying a Fender amp anytime soon. Maybe its an overreaction, but come on Fender. American quality used to mean something.
Any one complaining he only criticizes cheap new amps clearly hasn't watched the $5k vintage amp he says "the designers designed this wrong" lol
Well, it WAS on fire…
Few things are more annoying to a service tech than an amp that appears to operate correctly and doesn't exhibit the fault that the customer says it has; or perhaps the fault comes and goes randomly, and the device doesn't malfunction often enough or for a sufficiently long period of time that you can troubleshoot it.
@@goodun2974 My mechanic would approve this message. 😄
@@PsionicAudio"Sounded great just before it blew up!"