Fender Bassman 50 Heavy Maintenance
Moderated By: mods
Fender Bassman 50 Heavy Maintenance
Since someone asked if I could make some sort of journal or something about the maintenance on a bassman 50,.. here it is.
So the amp is an old fender bassman export (bassman 50).
This is in fact a picture I made after all of the work was done. I forgot making pictures of the state it was in when it got here. But it was just so realy bad.
This thing had been sitting in the attic for years. It even had mice droppings in it. The owner recently tried it, but he told me there was no sound, and he saw sparks coming out of the tubes.
It was equipped with RCA tubes, but they were just soo bad.
I think pictures say more than words.
Just look at the amount of dirt on the glass, and yes, most of the time it's not recommended to use power tubes that broke in two.
The preamp tubes had little cracks in the glass too.
So I began removing all of the tubes, and then checking the internals. The following picture is from after the work had been done.
With an amp of this age, it's the best thing realy to replace the electrolytic caps. (yes, the things that look like batteries). As for the film caps, they can handle time pretty well. The fat electrolytics just go bad over time. This one had the good old mallory caps, but they were in such a terrible state.. So I changed them for new ones. I marked them in the following picture.
Marked the 'work zones' in the next one.
These make up the power filter, so they constantly have to handle the high voltage.
The caps are hidden under a metal part that goes on top.
So, thats about everything I have pictures of. I had to do some other things like replacing a resistor that was broken in half, change a tube socket that was burned, and replaced the inputs as they were quite rusty.
If you have any questions, i'd like to answer them.
And yes, please keep in mind when you decide to work on your own amp, that these cute little things can store enough current to kill you even when they are turned off.
So the amp is an old fender bassman export (bassman 50).
This is in fact a picture I made after all of the work was done. I forgot making pictures of the state it was in when it got here. But it was just so realy bad.
This thing had been sitting in the attic for years. It even had mice droppings in it. The owner recently tried it, but he told me there was no sound, and he saw sparks coming out of the tubes.
It was equipped with RCA tubes, but they were just soo bad.
I think pictures say more than words.
Just look at the amount of dirt on the glass, and yes, most of the time it's not recommended to use power tubes that broke in two.
The preamp tubes had little cracks in the glass too.
So I began removing all of the tubes, and then checking the internals. The following picture is from after the work had been done.
With an amp of this age, it's the best thing realy to replace the electrolytic caps. (yes, the things that look like batteries). As for the film caps, they can handle time pretty well. The fat electrolytics just go bad over time. This one had the good old mallory caps, but they were in such a terrible state.. So I changed them for new ones. I marked them in the following picture.
Marked the 'work zones' in the next one.
These make up the power filter, so they constantly have to handle the high voltage.
The caps are hidden under a metal part that goes on top.
So, thats about everything I have pictures of. I had to do some other things like replacing a resistor that was broken in half, change a tube socket that was burned, and replaced the inputs as they were quite rusty.
If you have any questions, i'd like to answer them.
And yes, please keep in mind when you decide to work on your own amp, that these cute little things can store enough current to kill you even when they are turned off.
Not EVERYONE knows about their awesome potential with guitars? They're great clean amps that take anything you throw at them and they are built like fucking tanks. I have no idea why they go for such a low price either. Even early SF ab165 circuits average out around 500 or so and those are the "good ones"
I picked mine up for 3 bills but other than needing a good service its solid. Hasn't seen any maintenance since in 33 years and its still going strong! If you see one for $400 locally you owe it to yourself to at least go try it.
I picked mine up for 3 bills but other than needing a good service its solid. Hasn't seen any maintenance since in 33 years and its still going strong! If you see one for $400 locally you owe it to yourself to at least go try it.
i had just told isaac that today, something along the lines of "SF twins are like the holy grail" and how the Vintage ones can be had for about the same price as the RI models.
No idea about the v55, lots of people have been comparing it to the classic 50s though.
Not sure if you can switch over to EL34s either, out of my range of knowledge. Would have to be re-biased [?]
No idea about the v55, lots of people have been comparing it to the classic 50s though.
Not sure if you can switch over to EL34s either, out of my range of knowledge. Would have to be re-biased [?]
- robert(original)
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- Posts: 7174
- Joined: Thu Apr 20, 2006 12:30 pm
- Location: somewhere in the midwest
i recently had my bassman 10 amp fully service, i should have taken before and after pics but i didn't think of it.
i got my bassman ab165 dripedge thru a trade with aen. and my bassman 10 was 250 bucks, plus about 170 to get it completely re-done.
at one time i thought about buying about 3 old bassman heads just to keep around till they got valueable.
i got my bassman ab165 dripedge thru a trade with aen. and my bassman 10 was 250 bucks, plus about 170 to get it completely re-done.
at one time i thought about buying about 3 old bassman heads just to keep around till they got valueable.
awesome. $250?!robert(original) wrote:i recently had my bassman 10 amp fully service, i should have taken before and after pics but i didn't think of it.
i got my bassman ab165 dripedge thru a trade with aen. and my bassman 10 was 250 bucks, plus about 170 to get it completely re-done.
at one time i thought about buying about 3 old bassman heads just to keep around till they got valueable.
Silverface Champs go for next to nothing, too. Good recording amp?
- robert(original)
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- Posts: 7174
- Joined: Thu Apr 20, 2006 12:30 pm
- Location: somewhere in the midwest
get a bassman instead. loud enough for practice/gigs/good recording amp, great cleans.
and easy to repair, and think about it like this.
if my amp has been around for 40 years with minimal problems. then it will be around for another 40 years with moderate problems at worst.
think of a line 6 spider amp. if something goes wrong on the board, have fun fixing it yourself, you will have to send that shit off and wait for a long ass time, and in the end you will probly just get a new board installed and a bill from the company.
thats if the company even lasts for 5 more years.
and easy to repair, and think about it like this.
if my amp has been around for 40 years with minimal problems. then it will be around for another 40 years with moderate problems at worst.
think of a line 6 spider amp. if something goes wrong on the board, have fun fixing it yourself, you will have to send that shit off and wait for a long ass time, and in the end you will probly just get a new board installed and a bill from the company.
thats if the company even lasts for 5 more years.
Yeah. I hope I can get one before (if) the prices rocket, I just got an amp that will keep me going for a few years. My mind is plagued with tube amp horror stories about death and electrocution -- how do you guys go about fixing this? You can touch the caps? I guess what I mean is, will some things always hold a lethal charge, or is the entire thing dis chargeable?robert(original) wrote:get a bassman instead. loud enough for practice/gigs/good recording amp, great cleans.
and easy to repair, and think about it like this.
if my amp has been around for 40 years with minimal problems. then it will be around for another 40 years with moderate problems at worst.
think of a line 6 spider amp. if something goes wrong on the board, have fun fixing it yourself, you will have to send that shit off and wait for a long ass time, and in the end you will probly just get a new board installed and a bill from the company.
thats if the company even lasts for 5 more years.
- robert(original)
- .
- Posts: 7174
- Joined: Thu Apr 20, 2006 12:30 pm
- Location: somewhere in the midwest
- robert(original)
- .
- Posts: 7174
- Joined: Thu Apr 20, 2006 12:30 pm
- Location: somewhere in the midwest
- robert(original)
- .
- Posts: 7174
- Joined: Thu Apr 20, 2006 12:30 pm
- Location: somewhere in the midwest