Was this amp on the TDPRI forum? Its a "4565" Bandmaster. I used to have one. For 1 week, the 45th week of 1965, for some reason Fender used the power transformers from 1962 Bassman amps in the Bassman and Bandmasters which were built in "4565". They used a Zener diode to step down the voltages from the 1962 power transformers. That is why there is a mystery hole there in the chassis just to the left and below the bias pot. Dumble probably took that out when he put in the larger Fender Twin PT and left the hole there. Ive only see that mod and that particular 1962 Bassman PT on that particular week, 4565 Bandmasters and Bassmen.
I grew up in Santa Cruz and I had a crazy drummer friend who asked me if I wanted to go watch a guy build amps over in Pleasure Point. I said “why would anybody want to do that?” D’oh!
Thanks for sharing….I see something that needs to be checked… the photos of red covering on tube sockets… the socket furthest right side has a grid resistor which looks cooked to me. That can cause a transformer to fail…. You can look at brown carbon comp resistors on the tube socket those are grid resistors and they need to be 100% to avoid failure. That grey ash looking stuff is carbon and it needs to be cleaned off and that resistor replaced ,,, Those are gonna be old and bad anyway after that long of time…. So you dont want arcing there at all… The others dont look cooked but that means nothing since they were all done at same time… I would check the cap pan look at caps under cap pan dont touch they can shock you badly but take photo maybe or get them to check the caps If bubbled ends or leaking they need replacing also.. CRUCIAL TO MAINTAIN IT…. looks like 1.5k 5% 4.7ohm 2% blue resistors on tube sockets..those close tolerance and flame resistant also….. its pin 5 that might be an arching tube so the entire socket should be cleaned re tensioned all the carbon cleaned off it scraped off and solder cleaned out and part replaced with NOS values…. id do all of them at same time all the brown barrel carbon types on pin 5 …..Id bet once that is unsoldered it is broken through the colors or bands…. they get hot and break that way or blow up entirely breaking in half cooking worse… So you want to tell them to get on that clean all sockets re tension all tube sockets cleaning them alcohol after scrapping that off with solder tool… Id check the main filter caps 1st thing then go ahead and replace all the GRID RESISTORS and if MAIN FILTER CAPS ARE BAD REPLACE THEM and the Dropping strain resistors next to the Main filter caps… Those are also brown barrel types and common in fenders….they filter out noise … Those are all old and drifting at this point.. ** replacing main filter caps after 10 years is crucial anyway and it restores the power in all the ranges…the potentiometers or tone pots really come alive and the amp wont fail…. arching in tube sockets is instant death to a transformer and it might kill the person playing it especially if not grounded well with standoffs and the dang death cap being removed.. Large blue Mallory cap near the standbye switch.. DO NOT TOUCH IT….. DO NOT TOUCH MAIN FILTER CAPS EITHER …. The safe way to discharge those is unplug amp turn off and stand bye off take screw driver cross both positive and negative side of plug without touching screw driver part touching each side you can flip both switches and it will drain the charge from main filter caps so you can remove and replace them and not be shocked. DONT TRY THAT AT HOME IF YOU DONT KNOW WHAT YOUR DOING.. If this is in a shop they should know a tech qualified to do this work. its Crucial to have clean solder connections and pin connections and ive seen tube sockets arch internally between pins and thats bad news while playing the amp…. The mod of removing death cap helps prevent that from happening. I owned a Dumble bassman and it still had original death cap in it. Non grounded plug. I know exactly how to fix this amp and I just described how.. Simple repair crucial to the life of the amp and the overall tone and sound is everything. So you want all filtering caps working 100% and main filter caps also bias caps and diodes. The problem this amp will see is failure on one tube socket and soon as bias drifts to one side its going to roast the transformers and there goes the tone….. So prevent that by servicing this amp at once… Id be sick if that amp burned up or went down or worse hurt someone playing it thats dangerous to neglect so I pointed it out. By replacing Main caps if needed and these filter caps or grid resistors the tubes wont roast either…. you will just keep roasting that one tube till the transformer goes . Might catch fire or electrocute the player so not worth that… Those parts are easily found the brown barrel resistors are cheap quality id put ceramic as grid resistors especially since he upped the transformers to twin style 100 watters… those dissapate heat might put marshall style there… square white ceramic style or green barrel types good parts……. the blue resistors are close tolerance. he wants specific readings on the bias at bias board and at pin 5……you do not want the grids drifting out of tolerance… Id like to see the main filter caps under the cap pan and I spy some other type clay looking tan color caps or resistors mustard colored disk shaped types those and the blue flame retardant close tolerance Dumble would buy in bulk….id need to see the main boards Id bet orange drop or brown drop or blue drops.. Mine had orange drops and some other specific parts which were seen in other builds he did near that time…. mine was not smurfed…. recapping this amp and a tweak on the preamp tubes and even running it with a brown box is essential … The voltage at the wall is everything to a Dumble amp. The preamp tubes and voltages all matter so the parts must be maintained to proper specs and original maker if possible it matters… id not put F &T Caps in this either.. no way harsh and sterile sounding….. been there tried that…. you want specific wall voltage to the amp only way to ensure that is variac or brown box and brown box you can lower % and voltages without having to rebias the amp ! So you do that clean the tube sockets up check and retension sockets clean them out well spray cleaner and pushing tube in and out cleans them out well after re tensioning the sockets… There are some items he used at input and on tone stacks as mentioned. There are some changes on caps or resistors which change the cleans for the better .. a well tuned Dumble should sustain on the clean side straight in…. This amp needs service its dangerous to leave that resistor unchecked it will roast that tube and might take the transformer out. that means output transormer also ! DONT LET THAT SMOKE OUT SMOKEY BEAR SAYS ONLY YOU CAN PREVENT FIRES SAVE THE DUMBLE PUT OUT THE FIRE CHIEF… I can share some tips with tech if needed Im in Texas. I did repair work for major amp shops in Austin Dallas San Antonio and Houston most were sent into Austin to repair and ive done my own work since… This is a simple fix and it will improve the over all tone and reaction of the amp and the brown box and the right tubes will blow your minds. Raspy sounds brittle or to thin and the tone knobs reacting poorly or seemingly not doing much is a tell tale clue it needs caps…. I know it needs them they all do… and this one is roasted on that far right tube socket…. id call them tomorrow and tell them I spotted this and thought I should speak up. Tone is everything and so why not preserve and maintain it… I learned alot studying mine… The red anti arching paint also showed Dumble if the solder joints were tampered with or not if so he would not work on it again…. Mine had a different color on the solder joints. He hid resistors and wires and shrinkwrapped them hiding them beneath the boards to throw off discerning eyes. To see some of it took staring at it for hours and measuring or cross referencing schematics or layouts … Mine was a complete rebuild vs mod… ive seen inside several of these…
Thanks for the comment! I looked at that Grid Block resistor, it's ok, it has soot on it from (presumably) when the original Screen Grid Resistor blew. Someone went in and changed out the filter caps and did some other basic work (not to the standard of HAD), but I agree, it should be maintained and kept safe.
@@ChipsTipsforLife and herein lies the issue i have. IF dumble was indeed the difference in good vs great, unless he's the one selecting the needed to maintain components then what do you now have? near as i can surmise, it wasnt that he for example would replace a 100k plate load resistor with a 220k plate load resistor that made as much difference in sound as much as there was something about that particular resistor that made HAD select it. BUT, he's no longer with us & by most accounts it wouldnt have mattered if he was. I guess with his presence on earth the lore that HE touched it last could be perpetuated. and sold. So while lots of artists are tripping over themselves to buy his amps because of their increasing scarcity with his passing, i say the value greatly diminishes without his presence and/or ability to sustain the legacy. they need to be maintained, repaired sometimes sooner than later hell, a tube swap alone may have prompted AHD to make circuit changes to sustain what he had for goals with any given amplifier he engineered.i can't see where reality supports any other analogy. its an interesting set of circumstances, waaaay outside the scope of this video, im aware. i am a legendary over-thinker, admittedly & some of this may be in application as we speak so if it's hurting your brain, feel free to ignore it, lol. It was running thru my brain so i let my fingers do the walking.. btw, i picked your amp over the bandmaster in a blind test with one of my pals here who knows nothing about musical anything. i just asked him to check under which amp i said yes to. i like early breakup so... the bandmaster do seem to have a richer spectrum but im guessing thats easily changeable by a tone cap orvcathode bypass cap value change. keep up the great content !
Most likely a mid-boost and possibly a low end cut, making room for the highs in the signal. The extra output tubes are just that, more headroom. Also, the output transformer could very well be original: Fender Blackface amps & early Silverface amps used cloth covered wire until sometime in 1968
I lived in santa cruz in the early 70s. Howard Dumble had a shop and worked on amps. He stacked the preamps and put a master volume in a blackface fender showman for me. I'm sure it was one of the first amps he modded. I wonder what it would be worth now with the receipt.
great story! Can you tell me details please? Were you just a walk in customer? Did he work with your sound and style to decide what mods to make? How much did he charge? How long did he spend working on your amp? Generally speaking, an amp *authenticated to be a Dumble mod could sell in the 20k range...
@ChipsTipsforLife It was about 1971 maybe 72. I wanted to get more distortion at lower volume. I don't remember if it was my idea to wire the preamps in series or his. Putting master volumes on amps was just starting. It sounded great. As far as what happened to it I don't remember. Over 50 years ago so a long time. I've gone through many guitars and amps since then.
@@Jim-ro5sl thanks for the information! I wonder if the amp is still out there and if its current owner is aware they have an amp that was worked on by HAD?..
@@ChipsTipsforLife Sorry, but you guys are just adorable. Do you ever actually read what you write? I'm just reciting here: ‘...an amp *authenticated to be a Dumble mod could sell in the 20k range’ ..because of WHAT?? Because some guy (I'm sorry, your amp messiah Mr Dumble, of course) changed a few part values? 🤣 Come on, be honest, even the most brainwashed gear snobs among you are capable of recognising the sheer stupidity of all this, no?
@@ChipsTipsforLife I guess my question would be why anyone concluded that it was Dumble who modded the circuit. I don't see how anyone could tell that from a few resistors and caps.
@@stringtheoryx If you watched the part where I talk about his friendship with Jack Smith, it's not "anyone" who concluded who had done the mods in this amp. There are also specific soldering techniques, type of wire, the red dope, and a few other tiny but specific details that have been identified by experts. Ever watch Antique Road Show? Sometimes a tiny detail is a strong indentifier - ironically, it's for that reason I was asked to not include details on certain things because it would give copycats ways to try to mislead people and fetch the insane $ that's out there, it's happened.
Just listening to the amp nothing sounds special about what i just heard. Dumble or not. Even an original Dumble is not worth what people are asking for them.
that's fair. It sounds like a nice BF Fender (all the old blue molded caps etc.) with a LOT more output power, and the deep circuit really tames the high end, probably perfect for a certain player. Hard to explain how pleasing the tone is in the room, my Bassman is a chainsaw in comparison - And my playing/tone doesn't do it justice. The character of the tone is like my friend's brand new (2023) Gibson J45, it has a gentleness to the high end that at first I thought was "dull" but I've come to really appreciate how perfect it sounds no matter how hard you pick it, and perfect into a studio microphone. I'm usually prowling in vintage guitar shops for a Dreadnaught that has that "lighter than air" super vibrant quality that cuts through the mix in a live jam, but I'm coming around to the more controlled tones that are better in some situations. The prices people pay for collectibles is not something I get involved in. I hope you enjoyed the video!
![Robben Ford & His Dumble Overdrive Special [He Plays It, We Play It!]](http://i.ytimg.com/vi/4z-IkXE36DI/mqdefault.jpg)
Was this amp on the TDPRI forum? Its a "4565" Bandmaster. I used to have one. For 1 week, the 45th week of 1965, for some reason Fender used the power transformers from 1962 Bassman amps in the Bassman and Bandmasters which were built in "4565". They used a Zener diode to step down the voltages from the 1962 power transformers. That is why there is a mystery hole there in the chassis just to the left and below the bias pot. Dumble probably took that out when he put in the larger Fender Twin PT and left the hole there. Ive only see that mod and that particular 1962 Bassman PT on that particular week, 4565 Bandmasters and Bassmen.
I grew up in Santa Cruz and I had a crazy drummer friend who asked me if I wanted to go watch a guy build amps over in Pleasure Point. I said “why would anybody want to do that?” D’oh!
awesome story lol
Cool, I knew Jack. I played one at gadget box studios when I lived there.
Very cool! Thanks for watching
Thanks for sharing….I see something that needs to be checked… the photos of red covering on tube sockets… the socket furthest right side has a grid resistor which looks cooked to me.
That can cause a transformer to fail…. You can look at brown carbon comp resistors on the tube socket those are grid resistors and they need to be 100% to avoid failure. That grey ash looking stuff is carbon and it needs to be cleaned off and that resistor replaced ,,, Those are gonna be old and bad anyway after that long of time…. So you dont want arcing there at all… The others dont look cooked but that means nothing since they were all done at same time… I would check the cap pan look at caps under cap pan dont touch they can shock you badly but take photo maybe or get them to check the caps If bubbled ends or leaking they need replacing also..
CRUCIAL TO MAINTAIN IT…. looks like 1.5k 5% 4.7ohm 2% blue resistors on tube sockets..those close tolerance and flame resistant also….. its pin 5 that might be an arching tube so the entire socket should be cleaned re tensioned all the carbon cleaned off it scraped off and solder cleaned out and part replaced with NOS values…. id do all of them at same time all the brown barrel carbon types on pin 5 …..Id bet once that is unsoldered it is broken through the colors or bands…. they get hot and break that way or blow up entirely breaking in half cooking worse…
So you want to tell them to get on that clean all sockets re tension all tube sockets cleaning them alcohol after scrapping that off with solder tool… Id check the main filter caps 1st thing then go ahead and replace all the GRID RESISTORS and if MAIN FILTER CAPS ARE BAD REPLACE THEM and the Dropping strain resistors next to the Main filter caps… Those are also brown barrel types and common in fenders….they filter out noise … Those are all old and drifting at this point..
** replacing main filter caps after 10 years is crucial anyway and it restores the power in all the ranges…the potentiometers or tone pots really come alive and the amp wont fail….
arching in tube sockets is instant death to a transformer and it might kill the person playing it
especially if not grounded well with standoffs and the dang death cap being removed..
Large blue Mallory cap near the standbye switch.. DO NOT TOUCH IT…..
DO NOT TOUCH MAIN FILTER CAPS EITHER …. The safe way to discharge those is unplug amp
turn off and stand bye off take screw driver cross both positive and negative side of plug
without touching screw driver part touching each side you can flip both switches and it will drain the charge from main filter caps so you can remove and replace them and not be shocked.
DONT TRY THAT AT HOME IF YOU DONT KNOW WHAT YOUR DOING..
If this is in a shop they should know a tech qualified to do this work.
its Crucial to have clean solder connections and pin connections and ive seen tube sockets arch internally between pins and thats bad news while playing the amp….
The mod of removing death cap helps prevent that from happening.
I owned a Dumble bassman and it still had original death cap in it. Non grounded plug.
I know exactly how to fix this amp and I just described how..
Simple repair crucial to the life of the amp and the overall tone and sound is everything.
So you want all filtering caps working 100% and main filter caps also bias caps and diodes.
The problem this amp will see is failure on one tube socket and soon as bias drifts to one side its going to roast the transformers and there goes the tone…..
So prevent that by servicing this amp at once…
Id be sick if that amp burned up or went down or worse hurt someone playing it
thats dangerous to neglect so I pointed it out.
By replacing Main caps if needed and these filter caps or grid resistors the tubes wont roast either…. you will just keep roasting that one tube till the transformer goes .
Might catch fire or electrocute the player so not worth that…
Those parts are easily found the brown barrel resistors are cheap quality
id put ceramic as grid resistors especially since he upped the transformers to twin style 100 watters… those dissapate heat might put marshall style there… square white ceramic style or green barrel types good parts……. the blue resistors are close tolerance. he wants specific readings on the bias at bias board and at pin 5……you do not want the grids drifting out of tolerance…
Id like to see the main filter caps under the cap pan and I spy some other type clay looking tan color caps or resistors mustard colored disk shaped types those and the blue flame retardant close tolerance Dumble would buy in bulk….id need to see the main boards Id bet orange drop or brown drop or blue drops..
Mine had orange drops and some other specific parts which were seen in other builds he did near that time…. mine was not smurfed…. recapping this amp and a tweak on the preamp tubes and even running it with a brown box is essential …
The voltage at the wall is everything to a Dumble amp.
The preamp tubes and voltages all matter so the parts must be maintained to proper specs and original maker if possible it matters… id not put F &T Caps in this either..
no way harsh and sterile sounding….. been there tried that….
you want specific wall voltage to the amp only way to ensure that is variac or brown box
and brown box you can lower % and voltages without having to rebias the amp !
So you do that clean the tube sockets up check and retension sockets clean them out well
spray cleaner and pushing tube in and out cleans them out well after re tensioning the sockets…
There are some items he used at input and on tone stacks as mentioned.
There are some changes on caps or resistors which change the cleans for the better ..
a well tuned Dumble should sustain on the clean side straight in….
This amp needs service its dangerous to leave that resistor unchecked
it will roast that tube and might take the transformer out.
that means output transormer also !
DONT LET THAT SMOKE OUT
SMOKEY BEAR SAYS ONLY YOU CAN PREVENT FIRES
SAVE THE DUMBLE PUT OUT THE FIRE CHIEF…
I can share some tips with tech if needed Im in Texas.
I did repair work for major amp shops in Austin Dallas San Antonio and Houston
most were sent into Austin to repair and ive done my own work since…
This is a simple fix and it will improve the over all tone and reaction of the amp
and the brown box and the right tubes will blow your minds.
Raspy sounds brittle or to thin and the tone knobs reacting poorly or seemingly not
doing much is a tell tale clue it needs caps…. I know it needs them they all do…
and this one is roasted on that far right tube socket…. id call them tomorrow and tell them
I spotted this and thought I should speak up.
Tone is everything and so why not preserve and maintain it…
I learned alot studying mine…
The red anti arching paint also showed Dumble if the solder joints were tampered with or not
if so he would not work on it again….
Mine had a different color on the solder joints.
He hid resistors and wires and shrinkwrapped them hiding them beneath the boards
to throw off discerning eyes.
To see some of it took staring at it for hours and measuring or cross referencing schematics or layouts … Mine was a complete rebuild vs mod…
ive seen inside several of these…
Thanks for the comment! I looked at that Grid Block resistor, it's ok, it has soot on it from (presumably) when the original Screen Grid Resistor blew. Someone went in and changed out the filter caps and did some other basic work (not to the standard of HAD), but I agree, it should be maintained and kept safe.
@@ChipsTipsforLife and herein lies the issue i have. IF dumble was indeed the difference in good vs great, unless he's the one selecting the needed to maintain components then what do you now have? near as i can surmise, it wasnt that he for example would replace a 100k plate load resistor with a 220k plate load resistor that made as much difference in sound as much as there was something about that particular resistor that made HAD select it. BUT, he's no longer with us & by most accounts it wouldnt have mattered if he was. I guess with his presence on earth the lore that HE touched it last could be perpetuated. and sold.
So while lots of artists are tripping over themselves to buy his amps because of their increasing scarcity with his passing, i say the value greatly diminishes without his presence and/or ability to sustain the legacy. they need to be maintained, repaired sometimes sooner than later hell, a tube swap alone may have prompted AHD to make circuit changes to sustain what he had for goals with any given amplifier he engineered.i can't see where reality supports any other analogy. its an interesting set of circumstances, waaaay outside the scope of this video, im aware. i am a legendary over-thinker, admittedly & some of this may be in application as we speak so if it's hurting your brain, feel free to ignore it, lol. It was running thru my brain so i let my fingers do the walking..
btw, i picked your amp over the bandmaster in a blind test with one of my pals here who knows nothing about musical anything. i just asked him to check under which amp i said yes to. i like early breakup so... the bandmaster do seem to have a richer spectrum but im guessing thats easily changeable by a tone cap orvcathode bypass cap value change. keep up the great content !
@@Toobzilla in short, yes I agree lol.
Check my video where I add the same Dumble Deep circuit to my Bassman, now I have the best of both worlds!
Nice speaker cabinet, the secret to the tone is the lid of shake taped taped to the inside
I'm not sure I follow?... thanks for watching!
Very cool video and amp!
Most likely a mid-boost and possibly a low end cut, making room for the highs in the signal. The extra output tubes are just that, more headroom. Also, the output transformer could very well be original: Fender Blackface amps & early Silverface amps used cloth covered wire until sometime in 1968
Both transformers have codes for the Twin Reverb, ... Bassman 100, not original to Band Master.
I lived in santa cruz in the early 70s.
Howard Dumble had a shop and worked on amps. He stacked the preamps and put a master volume in a blackface fender showman for me. I'm sure it was one of the first amps he modded. I wonder what it would be worth now with the receipt.
great story! Can you tell me details please? Were you just a walk in customer? Did he work with your sound and style to decide what mods to make? How much did he charge? How long did he spend working on your amp?
Generally speaking, an amp *authenticated to be a Dumble mod could sell in the 20k range...
and the tough question... where is the amp now? (I assume you parted with it at some point?)
@ChipsTipsforLife It was about 1971 maybe 72. I wanted to get more distortion at lower volume. I don't remember if it was my idea to wire the preamps in series or his. Putting master volumes on amps was just starting. It sounded great. As far as what happened to it I don't remember. Over 50 years ago so a long time. I've gone through many guitars and amps since then.
@@Jim-ro5sl thanks for the information! I wonder if the amp is still out there and if its current owner is aware they have an amp that was worked on by HAD?..
@@ChipsTipsforLife Sorry, but you guys are just adorable. Do you ever actually read what you write? I'm just reciting here: ‘...an amp *authenticated to be a Dumble mod could sell in the 20k range’ ..because of WHAT?? Because some guy (I'm sorry, your amp messiah Mr Dumble, of course) changed a few part values? 🤣 Come on, be honest, even the most brainwashed gear snobs among you are capable of recognising the sheer stupidity of all this, no?
At first glance I see a bunch of stuff going on at the normal channel controls. Can't see what. I know they came wit four tube holes, two with covers.
check the explanation at 3:22
What makes that a Dumble? It's hard to see in the video, but there don't appear to be many changes.
well it's a "Dumble modified Bandmaster"
@@ChipsTipsforLife I guess my question would be why anyone concluded that it was Dumble who modded the circuit. I don't see how anyone could tell that from a few resistors and caps.
@@stringtheoryx If you watched the part where I talk about his friendship with Jack Smith, it's not "anyone" who concluded who had done the mods in this amp. There are also specific soldering techniques, type of wire, the red dope, and a few other tiny but specific details that have been identified by experts.
Ever watch Antique Road Show? Sometimes a tiny detail is a strong indentifier - ironically, it's for that reason I was asked to not include details on certain things because it would give copycats ways to try to mislead people and fetch the insane $ that's out there, it's happened.
Just listening to the amp nothing sounds special about what i just heard. Dumble or not. Even an original Dumble is not worth what people are asking for them.
that's fair. It sounds like a nice BF Fender (all the old blue molded caps etc.) with a LOT more output power, and the deep circuit really tames the high end, probably perfect for a certain player. Hard to explain how pleasing the tone is in the room, my Bassman is a chainsaw in comparison - And my playing/tone doesn't do it justice.
The character of the tone is like my friend's brand new (2023) Gibson J45, it has a gentleness to the high end that at first I thought was "dull" but I've come to really appreciate how perfect it sounds no matter how hard you pick it, and perfect into a studio microphone. I'm usually prowling in vintage guitar shops for a Dreadnaught that has that "lighter than air" super vibrant quality that cuts through the mix in a live jam, but I'm coming around to the more controlled tones that are better in some situations.
The prices people pay for collectibles is not something I get involved in.
I hope you enjoyed the video!