When I service something, I used to say repair, now, because of you, I say service, I always order a few(2 or more) extra parts in case I rune 1 or another amp of the same kind comes in so I don't have down time ordering a part. It is so nice to get a service and finish it the same day or even while the customer waits! Great info! Thankz
I spent the day setting up my work area, getting back to tube powered stuff. I’ve restored some fairly complex stuff but never any AA5 circuits. I see them all over eBay in rough shape & restored, and the prices between the two get me thinking of a cool retirement gig. Dim bulb tester, variac, func gen, scope, iso trans, meters, got it all ready to go. Except for sorting through scads of caps and resistors, that part won’t be fun at all 😳
Brad, if you could put together a 1-2 year course on old school amplifier/electronics repair, I would buy it! LOL! I am going to start an at home amp repair business in my hometown in Alabama. I have been in tile & stone business for 40 years. I have always played guitar in bands & worked on my own stuff (and my buddies) stuff for years. I have purchased all the equipment, books, charts, specs, schematics, etc. I need, but your personal knowledge & experience would be of great help! I wish there really was a Vulcan Mind Meld! Anyway, Thanks for your videos. I have gleaned much info from them.
Thanks. The issue of Capacitor values and types can make a huge difference. While I was going to DeVry they sold off a bunch of function generators that were broken. I bought one and changed out a Capacitor that I found to be the problem and replaced it with a Mylar Capacitor thinking it would do a better job than the older paper type it came with. Wrong! It worked but was too noisy. So sometime down the road I'll have to hunt down the correct Capacitor type and replace it along with the rest of the caps to make sure everything works in balance with each other.
Your tips are always appreciated, like when you said it's ok to touch tubes with your skin. Accidentally got my pecker caught twixt two 6L6's at a clothes optional gig and I wasn't wearing a jimmy. Thought I ruined a set of brand new JJ"s. Thanx!
+K McCoy this sort of thing is common. Once the penile skin heals from the 2nd degree burns, you'll be back to wearing spandex and doing air splits off the drum riser.
Ah this was a lovely one. Looking forward to building a simple champ like diy kit amp and perhaps modding it for like more tone controls and switches, similar to how you've modded some of the old champ like simple amps. Knowing approximately what value components you want to have to be able to conveniently experiment with common circuits helps a lot, not having to order again for every component you realize needing.
I think he might have dropped the ball on the .1uF 630V + - caps, as far as Fender circuits go and popularity... There's one for each 6L6 power and usually a couple in the preamp sections either overrated at 630 volts or two or four hundred volts. The old ones they just slap a big cap everywhere, the newer ones usually lower the voltage accordingly. I might have missed something I'm not trying to point out someone's mistake but more so I know what a pain it is to order and not have everything. I should probably watch the whole video before I start spouting off but why let manners get in the way.
I hate getting a 1/4 of the way thru a project because I need 2 caps and I only have 1 left in the bin, I need to keep a inventory list... I usually buy in bulk but they're assorted so I need to order certain values in bulk. I don't like B stock because the values are all over the place. I do want all my caps marked for the film end because I have had noise issues and when I switched them around the mysterious noise went away.
After my stint with tubes in the late 60's and early 70's I switched to all semiconductor for 40 years. The vast majority of my components I stock have been low voltage. Now that I'm getting back into tubes I have to get higher voltage caps, higher wattage resistors and an assortment of support hardware
Ever had a grander at the Epiphone Valve Senior schematic? Some of the cap and resistor values seem really weird. Second half of 1st 12ax7 has a plate resistor of 470k with a 4.7k cathode resistor. Also has a single 250 OHM cathode resistor for the two 6v6 power tubes.
Brad; a lot of the old caps from amps in the 50's& 60's were Polyester types. I've found that polyprop' scan be brighter/ harsher in amps. I don't know how many old British amps you work on, but I would get some Sozo's from Antique Electronics as the Sozo NexGen's are made exactly like the old mustard caps and to be frank, they sound better than almost all other caps I've tried and another great one are the polyester Wima caps made in Germany. Mouser stocks those. The Wima's sound great in the reissue Fender amps.
Youre a lot more organized with your caps and resistors than I am. Only thing sucky about axial lead electrolytic caps is that they cost more than radial, heven't figured out why yet.
I clipped the bright cap on my Deluxe Reverb Reissue a few years ago and now I kinda wash I hadn’t. It helps for my brighter guitars but humbuckers are just way too dark now. May need to see what you can do for me.
If you have an amp that when you turn it on go to 480v and then go down to 380 + or -, what filter caps you go with? are 450v ok or i have to do something else? i put 3 filter caps at 450v...the amp for now is going ok but to see what u think its more safe
Hey Brad, I always make sure I play a full commercial when I visit your site. If there isn’t one, I reload until I get one and then make sure I play the whole commercial. Always. What happens to those funds when ‘you know who’ holds back their funding? Do you have any idea? Just curious...
Make some cash off this sell kits with common caps/resistors in a cheap tackle box or little bin like your resistors are in. Buy in large bulk to save yourself a lot and make it worth your time in the end. I’d take one, anyone else?
I agree on those being a good basic stock list. My only comment is, I’m also a firm believer that the only acceptable plate resistor for a 12ax7 is 100k. Use of 220k resistors as 12ax7 plate resistors is a crime against humanity.
This should has nothing to do with this video.all of which are informative and entertaining I was wondering if anyone knows where to look up current values of rare and valuable amps. I found an article in a magazine can't remember what one but every thing I can find was written years ago. Mabe one of your listeners or you would know the current value of my 59 fender twin.
Hey Brad, good mornin gent. Can you recommend a decent meter for under or around 100 bills? I'm tired of these sub 35 dollar models. Limitations and I had a Commercial Electric model develop a short inside of 6 months. Time to bite the bullet. Thanks.
Sorry for the late reply. Looks like you can get a really decent Fluke for around $80 here. This has most everything you'll need and it should be fused and safe to operate: www.banggood.com/Fluke-15B-F15B-Professional-Auto-Range-Digital-Multimeter-Tester-p-911684.html?p=@0210017420670201712
Thanx Brad, I actually had seen that same model but was holding off until I could see if it would take care of what I need. Thanks again and have a great Holiday and I hope your girls get what they want from Santa!
Brad-I have a question. I just ordered a lowry organ amp off ebay.-Can I use a dimmer switch to make a variac? I think I have a meter somewhere around here that I could use to see how much voltage is being shown. Thanks for any help.
Super helpful and informative video. I'd love to send you some handmade precision wire wound resistors to use in your future videos, on the house, if you'd be interested. Just reach out to me and ill ship out what you need. Cheers.
buy quality caps like Nichicon, Elna, Panasonic, and Rubycon and you'll never have to worry about it. the cap formulas really improved over the last 10 years
Correct, PLUS from 2001-2010 a Chinese company was producing crappy electrolyte that caused rapid failure from caps. These ended up in tons of computers. That saga is ended, and most branded caps are good. If you get them from a real distributor (Digikey, Mouser, CE, Jameco..) rather than rolling dice with Ebay or Aliexpress, you'll be good.... counterfeit caps do exist.
Actually its easier to stock a shop than stock your car. I used to do mobile service on coin op games ad monitor repair was similar to amp repair. High voltage galore. I stocked tons of caps and for everything else, I carted around old chassis I grabbed parts out of. No you don't recap in the field, you change 1 to 3 usually.
Hey, Brad! I guess I didn't have a correct email for you because the message I sent came back undeliverable. Here's the link to the S-Town podcast I'd mentioned on an earlier video: stownpodcast.org Maybe I'll cut/paste the email message and send it you via your channel page here on UA-cam. I wrote a few additional things in it and it's too long to share in the comments section.
Feel free to show the japanse guitar parts you stock. I try to watch all the videos I can not to plague you with questions already answered. 😂😂😂 thanks!
Anyone who repairs guitar amps should have all capacitors and resistors and vacuum tubes needed to replace a guitar amp solid state guitar amps are not economically worth replacing as it is better to buy a replacement unit and anyway must units have a warning that there are no user serviceable parts inside, it is possible to build a guitar amp around a NE556 plus a 74HC00 and MJ3055 power transistors which would give you a PWM amp which should be able to drive a 20" 4R speaker google it it is out there.
When I service something, I used to say repair, now, because of you, I say service, I always order a few(2 or more) extra parts in case I rune 1 or another amp of the same kind comes in so I don't have down time ordering a part. It is so nice to get a service and finish it the same day or even while the customer waits! Great info! Thankz
I spent the day setting up my work area, getting back to tube powered stuff. I’ve restored some fairly complex stuff but never any AA5 circuits. I see them all over eBay in rough shape & restored, and the prices between the two get me thinking of a cool retirement gig.
Dim bulb tester, variac, func gen, scope, iso trans, meters, got it all ready to go.
Except for sorting through scads of caps and resistors, that part won’t be fun at all 😳
Brad, if you could put together a 1-2 year course on old school amplifier/electronics repair, I would buy it! LOL! I am going to start an at home amp repair business in my hometown in Alabama. I have been in tile & stone business for 40 years. I have always played guitar in bands & worked on my own stuff (and my buddies) stuff for years. I have purchased all the equipment, books, charts, specs, schematics, etc. I need, but your personal knowledge & experience would be of great help! I wish there really was a Vulcan Mind Meld! Anyway, Thanks for your videos. I have gleaned much info from them.
Thanks. The issue of Capacitor values and types can make a huge difference. While I was going to DeVry they sold off a bunch of function generators that were broken. I bought one and changed out a Capacitor that I found to be the problem and replaced it with a Mylar Capacitor thinking it would do a better job than the older paper type it came with. Wrong! It worked but was too noisy. So sometime down the road I'll have to hunt down the correct Capacitor type and replace it along with the rest of the caps to make sure everything works in balance with each other.
Your tips are always appreciated, like when you said it's ok to touch tubes with your skin. Accidentally got my pecker caught twixt two 6L6's at a clothes optional gig and I wasn't wearing a jimmy. Thought I ruined a set of brand new JJ"s. Thanx!
+K McCoy this sort of thing is common. Once the penile skin heals from the 2nd degree burns, you'll be back to wearing spandex and doing air splits off the drum riser.
Ah this was a lovely one. Looking forward to building a simple champ like diy kit amp and perhaps modding it for like more tone controls and switches, similar to how you've modded some of the old champ like simple amps. Knowing approximately what value components you want to have to be able to conveniently experiment with common circuits helps a lot, not having to order again for every component you realize needing.
I think he might have dropped the ball on the .1uF 630V + - caps, as far as Fender circuits go and popularity... There's one for each 6L6 power and usually a couple in the preamp sections either overrated at 630 volts or two or four hundred volts. The old ones they just slap a big cap everywhere, the newer ones usually lower the voltage accordingly. I might have missed something I'm not trying to point out someone's mistake but more so I know what a pain it is to order and not have everything. I should probably watch the whole video before I start spouting off but why let manners get in the way.
I think of more importance would be, what brands do you stock in your beer fridge, and what's in the liquor cabinet?
I hate getting a 1/4 of the way thru a project because I need 2 caps and I only have 1 left in the bin, I need to keep a inventory list... I usually buy in bulk but they're assorted so I need to order certain values in bulk. I don't like B stock because the values are all over the place. I do want all my caps marked for the film end because I have had noise issues and when I switched them around the mysterious noise went away.
I have a crate amplifier in the fuse You just showed. Broke off from the solder joint 😢
Organization is half the battle... I think you loose interest in what you're doing when everything is a mess. Great video, thanks :)
After my stint with tubes in the late 60's and early 70's I switched to all semiconductor for 40 years. The vast majority of my components I stock have been low voltage. Now that I'm getting back into tubes I have to get higher voltage caps, higher wattage resistors and an assortment of support hardware
Wow, your camera focuses like a boss!
Ever had a grander at the Epiphone Valve Senior schematic? Some of the cap and resistor values seem really weird. Second half of 1st 12ax7 has a plate resistor of 470k with a 4.7k cathode resistor. Also has a single 250 OHM cathode resistor for the two 6v6 power tubes.
Brad; a lot of the old caps from amps in the 50's& 60's were Polyester types. I've found that polyprop' scan be brighter/ harsher in amps. I don't know how many old British amps you work on, but I would get some Sozo's from Antique Electronics as the Sozo NexGen's are made exactly like the old mustard caps and to be frank, they sound better than almost all other caps I've tried and another great one are the polyester Wima caps made in Germany. Mouser stocks those. The Wima's sound great in the reissue Fender amps.
Youre a lot more organized with your caps and resistors than I am. Only thing sucky about axial lead electrolytic caps is that they cost more than radial, heven't figured out why yet.
For screens, I'd stock 5 watt 470 for fender and 5 watt 1k for Marshall types.
Would you recommend NTC Thermistors to save filament flash?
Great selection to fall back on there bro.
I clipped the bright cap on my Deluxe Reverb Reissue a few years ago and now I kinda wash I hadn’t. It helps for my brighter guitars but humbuckers are just way too dark now. May need to see what you can do for me.
If you have an amp that when you turn it on go to 480v and then go down to 380 + or -, what filter caps you go with? are 450v ok or i have to do something else? i put 3 filter caps at 450v...the amp for now is going ok but to see what u think its more safe
Why is the voltage rating only 160V for transformer less amplifiers? I guess when you design a transformer less amplifier it can only use 160V max?
Hey Brad, I always make sure I play a full commercial when I visit your site. If there isn’t one, I reload until I get one and then make sure I play the whole commercial. Always. What happens to those funds when ‘you know who’ holds back their funding? Do you have any idea? Just curious...
Make some cash off this sell kits with common caps/resistors in a cheap tackle box or little bin like your resistors are in. Buy in large bulk to save yourself a lot and make it worth your time in the end. I’d take one, anyone else?
I agree on those being a good basic stock list. My only comment is, I’m also a firm believer that the only acceptable plate resistor for a 12ax7 is 100k. Use of 220k resistors as 12ax7 plate resistors is a crime against humanity.
What about flux capacitors?
Do you suggest stocking those?
If you wanna get Back to the Future, you better have them in stock.
You're gonna need to stock bolts of lightning then.
This should has nothing to do with this video.all of which are informative and entertaining I was wondering if anyone knows where to look up current values of rare and valuable amps. I found an article in a magazine can't remember what one but every thing I can find was written years ago. Mabe one of your listeners or you would know the current value of my 59 fender twin.
Hey Brad, good mornin gent. Can you recommend a decent meter for under or around 100 bills? I'm tired of these sub 35 dollar models. Limitations and I had a Commercial Electric model develop a short inside of 6 months. Time to bite the bullet. Thanks.
Sorry for the late reply. Looks like you can get a really decent Fluke for around $80 here. This has most everything you'll need and it should be fused and safe to operate: www.banggood.com/Fluke-15B-F15B-Professional-Auto-Range-Digital-Multimeter-Tester-p-911684.html?p=@0210017420670201712
Thanx Brad, I actually had seen that same model but was holding off until I could see if it would take care of what I need. Thanks again and have a great Holiday and I hope your girls get what they want from Santa!
if a resistor blows(say a 100k), is it because of an old resistor or evidence of something else before it?
Brad-I have a question. I just ordered a lowry organ amp off ebay.-Can I use a dimmer switch to make a variac? I think I have a meter somewhere around here that I could use to see how much voltage is being shown. Thanks for any help.
+why not me no on the dimmer switch. It chops the AC wave to achieve a dimmer bulb. A variac varies the voltage.
thanks
This video was demonetized this afternoon sometime, 12/18.
What is a kentucky fire cured flying pig?
Super helpful and informative video. I'd love to send you some handmade precision wire wound resistors to use in your future videos, on the house, if you'd be interested. Just reach out to me and ill ship out what you need. Cheers.
What about gas filled zener ditroids?
Forgot about those. I use them everyday as suppositories.
Nice
first ;-) cheers brad hope u have a merry christmas :-) any decision on the reel 2 reel yet?
Not yet. Merry Christmas.
so, the ones not labeled pf; are they mf ? .022 & .047 or .0047 ?
+Jason Kirkham yes. They are arranged in order of size.
The Guitologist thank you
You don't worry about the electrolytic caps aging in storage? I guess you stock mostly inexpensive ones...
My thought is....... It's OK to stock new Electrolytics in values that you will use in the next few years. The "cap plague" is over...
buy quality caps like Nichicon, Elna, Panasonic, and Rubycon and you'll never have to worry about it. the cap formulas really improved over the last 10 years
Correct, PLUS from 2001-2010 a Chinese company was producing crappy electrolyte that caused rapid failure from caps. These ended up in tons of computers. That saga is ended, and most branded caps are good. If you get them from a real distributor (Digikey, Mouser, CE, Jameco..) rather than rolling dice with Ebay or Aliexpress, you'll be good.... counterfeit caps do exist.
+Crunch2 I don't keep many electrolytics in stock at a time. 10 of each value, maybe.
DeadKoby you can go to Goodwill and pick up TV's cheep and just recap them.
Thanks Dude
Actually its easier to stock a shop than stock your car. I used to do mobile service on coin op games ad monitor repair was similar to amp repair. High voltage galore. I stocked tons of caps and for everything else, I carted around old chassis I grabbed parts out of. No you don't recap in the field, you change 1 to 3 usually.
Hey, Brad! I guess I didn't have a correct email for you because the message I sent came back undeliverable. Here's the link to the S-Town podcast I'd mentioned on an earlier video:
stownpodcast.org
Maybe I'll cut/paste the email message and send it you via your channel page here on UA-cam. I wrote a few additional things in it and it's too long to share in the comments section.
Feel free to show the japanse guitar parts you stock. I try to watch all the videos I can not to plague you with questions already answered. 😂😂😂 thanks!
Anyone who repairs guitar amps should have all capacitors and resistors and vacuum tubes needed to replace a guitar amp solid state guitar amps are not economically worth replacing as it is better to buy a replacement unit and anyway must units have a warning that there are no user serviceable parts inside, it is possible to build a guitar amp around a NE556 plus a 74HC00 and MJ3055 power transistors which would give you a PWM amp which should be able to drive a 20" 4R speaker google it it is out there.