My Ampeg B100R Rocket Bass

[esalutation]

Greetings all!

I’ve wanted to repair this amp for awhile, and would kindly appreciate your opinion & expertise. I originally got this amp used in the late 00’s, it’s taken a beating but I always loved the sound for lower volume settings. Since it stopped working for almost a decade now, it’s been garage-sitting. Biggest issue is the fried right-side of the board. The headphone jack and back cover also need replacement.

To DIY repair, how would you approach the electronics specifically? I’m asking to see how possible this is to fix/troubleshoot myself, as I’m guessing a pro repair job would cost as much as or more than another similar amp. I can only assume that it won’t be as simple as ordering/replacing the whole circuit board. It’s been sitting so long, so I’d want every part checked and tested out.

Please go easy on me, I’m just a drummer who still plays bass occasionally!

Thanks for reading. -es

 

[basscooker]

You could kill two birds with one stone, for the price of a bench fee. You'd know what's wrong AND if it is worth fixing compared to moving on.

 

[JimmyM]

In one of the great tragedies of combo amp history, the B100R was discontinued in 2010 because it was priced higher than the BA115 and didn't sell well enough for LOUD to keep it. So the likelihood of getting a new PCB for it is nil. However, if you're skilled with PCB soldering and making new traces, you could get hold of the schematic (which I'm pretty sure is a Google search away), get all the part values, and replace all the burned parts and make new traces. The only problem with that is it may have taken out stuff you don't know it took out, which is where techs come in handy.

Personally, I'd like to see as many of these amps out there as possible, but yeah, it might cost some money to have a pro do it. Think of it as a labor of love, though, and try to forget return on your dollars.

 

[esalutation]

Thanks JimmyM for the history! I’ve already reached out to the nearest authorized dealer listed on Ampeg’s site, which also had schematics for it as well.

 

[MtManiac]

I just picked up a B100R yesterday at a pawn shop for CAD$250. Some dust on the lateral surfaces, but otherwise works perfectly, including the power light. What a sound! Great tone at all volumes. If you can’t fix it, I definitely recommend seeing if you can find one on the used market. I snagged mine up as soon as I saw it.

Mine’s a 2002 St Louis model.

 

[Les Fret]

Personally, I'd like to see as many of these amps out there as possible

I have one and like it for small to medium gigs for when I am too lazy to bring my bigger rig.
It works fine for that. What do you all think of this amp? You don't see them very often.

 

[Coolhandjjl]

One of the best combo’s ever. Lots of luv for them here. Start combing through CL and GC for a replacement

 

[MtManiac]

Greetings all!

I’ve wanted to repair this amp for awhile, and would kindly appreciate your opinion & expertise. I originally got this amp used in the late 00’s, it’s taken a beating but I always loved the sound for lower volume settings. Since it stopped working for almost a decade now, it’s been garage-sitting. Biggest issue is the fried right-side of the board. The headphone jack and back cover also need replacement.

To DIY repair, how would you approach the electronics specifically? I’m asking to see how possible this is to fix/troubleshoot myself, as I’m guessing a pro repair job would cost as much as or more than another similar amp. I can only assume that it won’t be as simple as ordering/replacing the whole circuit board. It’s been sitting so long, so I’d want every part checked and tested out.

Please go easy on me, I’m just a drummer who still plays bass occasionally!

Thanks for reading. -es

View attachment 3710960View attachment 3710961View attachment 3710962

If you decide to replace it, I’ll buy the handle on this one from you.

 

[BrentSimons]

If I remember correctly, Michael Anthony used his Ampeg Rocket 50 to record the first few Chickenfoot albums. That's a pretty good testimony I think?

 

[JimmyM]

I have one and like it for small to medium gigs for when I am too lazy to bring my bigger rig.
It works fine for that. What do you all think of this amp? You don't see them very often.

Next best thing to a real tube Portaflex if you ask me. And man, do I wish they'd bring them back.

 

[BogeyBass]

Takes alot of time to remove the goop alone, then clean all that carbon.
then hope the traces are not damaged. then still kinda grind your teeth cause the thinner boards
will carbon track in the pcb substrate itself.

then again ive seen pretty bad looking boards clean up pretty good.

but yeah a tech wouldnt touch it, or if willing
the cost of labor would be higher than buying another one.

good news is its a gorgeous cabinet, and i dont know why either
that this combo didnt do better.
been few threads lately on this series. guys remove the amps and just use the cabinet

you mentioned the headphone jack needs replacing? they headphone jack also switched off the speaker and if the jack toasted
ill assume the output devices might have failed and then took out everything driving them with it.

looking at the board it basically looks like the opamp and diodes/power supply/ bias section of the amp driver.
its a very very simple amp. but dam looks like a output short eats everything.

people tend to like the 100R better for some reason, i like the 200 mosfet version, basically a beefier version of the BA115 output amplifier
ive never owned one. but repaired alot of ba115 and actually like the simple designs that SLM used for their combo amps

you can see a zener that burned up and this is common with slm amps. but looks like the tlo74 burned up good too. and a few passives associated with the circuit

 

[qwench]

In relevance to this thread, I spied a used B50R in Canada for super cheap and had the local chain store bring the unit it in for me to give to my youngest who is a budding bass player...I plugged it in and realized that it got loud very quickly, there wasn't a very kind, gradual increase in volume...it went from: off to fairly loud. But right away I was in amazement of how great it sounded...my kid looked at me and asked what was wrong...I said, nothing but we will go back to the store on the weekend and get you a different bass amp (got him the Rumble 100 combo) and Daddy is putting this old Ampeg B50R in the studio!!!

It really squashed the amp gas for me and I am not gigging much these days but if I do, I will throw a Radial JDI in the bag and take this "little but loud combo"...very reasonable variation on the real deal tube Portaflex as JimmyM eluded to above!!!

I actually think I prefer the lesser weight of the B50R to the B100R (that I had as a rental amp years back!) and it gets really loud for a 12"...both sounded great though...maybe the Yamaha folk will whip up a new version of these beasts!!!!

 

[Hot Rats]

In relevance to this thread, I spied a used B50R in Canada for super cheap and had the local chain store bring the unit it in for me to give to my youngest who is a budding bass player...I plugged it in and realized that it got loud very quickly, there wasn't a very kind, gradual increase in volume...it went from: off to fairly loud. But right away I was in amazement of how great it sounded...my kid looked at me and asked what was wrong...I said, nothing but we will go back to the store on the weekend and get you a different bass amp (got him the Rumble 100 combo) and Daddy is putting this old Ampeg B50R in the studio!!!

It really squashed the amp gas for me and I am not gigging much these days but if I do, I will through a Radial JDI in the bag and take this "little but loud combo"...very reasonable variation on the real deal tube Portaflex as JimmyM eluded to above!!!

I actually think I prefer the lesser weight of the B50R to the B100R (that I had as a rental amp years back!) and it gets really loud for a 12"...both sounded great though...maybe the Yamaha folk will whip up a new version of these beasts!!!!

Awesome. For kicks after reading this thread, I searched for a B100R and found a B50R used at guitar center and it is now on it's way to me (I hope...what the the country shutting down and all) and the wait is gonna be tough.

 

[SwitchGear]

Skip the repair and buy a Rumble 100.

A loud 22 lbs of great tone

Thank me later



(Former B100R owner)

 

[JimmyM]

Awesome. For kicks after reading this thread, I searched for a B100R and found a B50R used at guitar center and it is now on it's way to me (I hope...what the the country shutting down and all) and the wait is gonna be tough.

Nice...let us know how it turns out for you. Never got to play one. Only the B100R.

 

[esalutation]

Thank you all for your thoughts and feedback! As predicted, it’d cost well over the cost of a new similar amp to service this amp, so it shall continue to nest in my garage. Still no luck on finding a replacement PCB, but it’s possible I could “frankenstein” it if the dice fall that way. I’ll be eyeing similar amps for sale (B50r/Rmble100) but am in no rush.

 

[Ric Vice]

Next best thing to a real tube Portaflex if you ask me. And man, do I wish they'd bring them back.

Agreed,
The B50R and the B100R were really nice amps. I remember when they were released, along with the B-15NR. I don't know how they did it, but those amps sound like B-15's, weigh less and have more power.
It's a real testament to the early SLM/Loud partnership. I believe they were made at the factory in Arkansas. They also built the Portabass line there. I knew several Double Bass players who bought them and loved them.
They were very sturdy amplifiers.

 

[Les Fret]

Anyone ever tried an B200R? How does it compare to the B100R?

 

[Ric Vice]

As I recall the B200R came after the B100 and B50R's I think the only difference was the power section. The Preamp and Speaker Enclosure were the same.

 

[lowendrv]

As I recall the B200R came after the B100 and B50R's I think the only difference was the power section. The Preamp and Speaker Enclosure were the same.