Ampeg B-100r Rocket Aficionados

[Michael Eisenman]

Yo @Michael Eisenman, I was able to get a pic of my serial number and am confused.

Here's the serial number from my B100R:

View attachment 7161279

It says made in USA on the chrome chassis on the top of the unit, the other sticker next to the serial number says SLM, inside the components says SLM. I'm pretty sure it's US made, but I wonder what to make of the X in the spot that indicates country? From your document and the Ampeg website section that deals with serial dating (both seem to be the same), one would expect to see a Y for Europe, U for UK, W for world wide or D for domestic.

ABR = Model designation (B-100R, I assume)
X = ? I believe that the B-200Rs were made in China, but I don’t think that any B-100Rs were, and yours says “Made in USA”. Maybe Ampeg can tell you.
NB = 2001 December
0100 = Actual S/N (for 2001 December, I assume)

 

[Lowbrow]

I’m happy this thread got revived (again) cause it’ll make me roll the old B100R out of the closet for a spin.

 

[Michael Eisenman]

I took my B-100R last night to a gig, and the darned thing was rolling around in the back of my car, even after trying to block it in place with other gear. I’m going to look for some casters—only need two—with brakes; the casters that I recommended are fine otherwise.

I bought a set of 3-inch casters with brakes, and they do the trick. There were a couple of sets on Amazon: a set with four brakes, and a set with two. Here they are:

• Amazon.com
• Amazon.com

You need 7/16” dia x 1⅜” length, grip-ring stem.

 

[shadven]

3 in a row. Loving this amp.

View attachment 7015296

I did a bunch of gigs with two of them at the same time. They sounded great. I always keep one in my arsenal.

 

[bthiemann80]

Aficionados! I am in need of some help.

My B100R has fallen ill to the all too common malady of bad headphone jack. It started when I noticed a slight bit of fuzz/crackle along with slight fluctuations in volume on some notes in a not very common and random way. I'll spare the troubleshooting details, but suffice it to say I was able to rule out guitar, cable, input jacks, speaker and speaker leads. She's also been thoroughly cleaned enough times to make a dentist smile, or a nun

BTW, huge shout out to the folks who have documented such issues and subsequent troubleshooting on this board! Looking at you @anderbass, @Chuter, @Jay Corwin, @FunkyWilly and many others that I cannot tag or think of at the moment. Without your collective help, I probably would be looking to sell it at a loss instead of fix it up for a gain

I am having trouble getting a amp tech to look at it, as the ones in our area claim to only service tube amps. So I may have to scrub up myself....

I am thinking the best way for a ham fisted, simple minded dude like me to fix this is to bypass the headphone jack. I have never used a headphone out on a amp and do not plan to. I have looked over the schematics and am wondering if it is just a matter of pulling the old jack and installing jumpers to go across where the 6 jack legs were (3 jumpers total). Then of course, blocking the hole.

Has anyone had experience with this and/or able to offer any caveats/insights/dirty jokes?

 

[morrisonhendrix]

This may have been discussed before (I searched this thread with not much luck), but my B100R will play fine and then the volume will drop a lot. I can slap the bass and it will pop back up to the previous volume level. This behavior will typically continue while I play, although there are times when it may not drop volume for a little while. I've used Deoxit on both input jacks, with a little success, but it usually either doesn't last long, or doesn't help at all. Does the input jack need to be replaced?

 

[bthiemann80]

This may have been discussed before (I searched this thread with not much luck), but my B100R will play fine and then the volume will drop a lot. I can slap the bass and it will pop back up to the previous volume level. This behavior will typically continue while I play, although there are times when it may not drop volume for a little while. I've used Deoxit on both input jacks, with a little success, but it usually either doesn't last long, or doesn't help at all. Does the input jack need to be replaced?

Based on the data I’ve seen on here, I’d say give the headphone jack a thorough cleaning, including a good rodgering with a 1/4 plug and use contact cleaner. If that doesn’t fix it, check the wires running to the speaker from the amp and that they are solidly connected on both ends. If that doesn’t fix it, I’d say replace or bypass the headphone jack. Not sure past that.

Others will chime in with more info too I hope. Good luck.

 

[Chuter]

I left the original phono jack and soldered jumpers across the PC board pins of the jack. Use quick disconnects if you think you’ll ever want to use phones again.
The problem with mine was weak contact springs on the jack, not oxidation or dirt. Could have replaced the jack but they’re a little hard to find.

 

[bthiemann80]

I left the original phono jack and soldered jumpers across the PC board pins of the jack. Use quick disconnects if you think you’ll ever want to use phones again.
The problem with mine was weak contact springs on the jack, not oxidation or dirt. Could have replaced the jack but they’re a little hard to find.

Check this place out, about half way down. Seems pretty reasonable:

Ampeg and Crate Parts

Studio Sound Electronics Parts for Ampeg and Crate Amplifiers

amprepairparts.com

I had though about just replacing the jack, but I really have no use for it and would MUCH rather have a solid electrical path for sound than the option to use headphones infrequently and run the risk of the issue occurring again down the road.

I was able to find someone who was willing to work on the amp locally. I dropped it off with them yesterday. They said they're backed up and gave no estimated time for completion, but I'll be sure to report back with any updates.

 

[bthiemann80]

I wanted to offer an update on this.

Amp came back from tech, said headphone jack was fine. Diagnosis from the receipt says "Discovered a lot of bad solder joints and lifted traces on back side of circuit board".

Picked it up last Friday and fired it up that evening. Sounded and worked as advertised (though the power light is still out, which has been the case since I bought it and I told the tech not to worry about it as I was concerned that it would rack the repair cost too high). The work he did brought back the previously non working signal/peak lights too.

Damn.......this amp sounds good. Among the very best I have played through.

Plugged it back again to play through it again the next morning (saturday) and nothing. It powered up, sound was coming from line out, phones and I was able to rule out cable/guitar and speaker. I had the back off and during the troubleshooting, I wiggled the speaker connections at the PC board and as I was wiggling the black one, sound came back. I noticed it started doing the same fizzy/scratchy sound at the end of notes (the very reason I took it in to have worked on in the first place), so I focused my attention on the black speaker connection at the PC board. I popped it off, re crimped it so it would have a stronger/tighter connection, and played some more. That seemed to fix it, but I thought at one point I could hear some of the fizzy/scratchy sound again, but could have been mistaken.

I was able to play through it today for a bit and there was no issue at all. Just glorious b100r sound.

I plan to continue playing through it as much as time allows and at the next band practice. So we will see how all that goes. Hopefully it holds up! I'll try to report back.

 

[Lowbrow]

I wanted to offer an update on this.

Amp came back from tech, said headphone jack was fine. Diagnosis from the receipt says "Discovered a lot of bad solder joints and lifted traces on back side of circuit board".

Picked it up last Friday and fired it up that evening. Sounded and worked as advertised (though the power light is still out, which has been the case since I bought it and I told the tech not to worry about it as I was concerned that it would rack the repair cost too high). The work he did brought back the previously non working signal/peak lights too.

Damn.......this amp sounds good. Among the very best I have played through.

Plugged it back again to play through it again the next morning (saturday) and nothing. It powered up, sound was coming from line out, phones and I was able to rule out cable/guitar and speaker. I had the back off and during the troubleshooting, I wiggled the speaker connections at the PC board and as I was wiggling the black one, sound came back. I noticed it started doing the same fizzy/scratchy sound at the end of notes (the very reason I took it in to have worked on in the first place), so I focused my attention on the black speaker connection at the PC board. I popped it off, re crimped it so it would have a stronger/tighter connection, and played some more. That seemed to fix it, but I thought at one point I could hear some of the fizzy/scratchy sound again, but could have been mistaken.

I was able to play through it today for a bit and there was no issue at all. Just glorious b100r sound.

I plan to continue playing through it as much as time allows and at the next band practice. So we will see how all that goes. Hopefully it holds up! I'll try to report back.

Might the fizzy sound be a dusty pot?

 

[Michael Eisenman]

I wanted to offer an update on this.

Amp came back from tech, said headphone jack was fine. Diagnosis from the receipt says "Discovered a lot of bad solder joints and lifted traces on back side of circuit board".

Picked it up last Friday and fired it up that evening. Sounded and worked as advertised (though the power light is still out, which has been the case since I bought it and I told the tech not to worry about it as I was concerned that it would rack the repair cost too high). The work he did brought back the previously non working signal/peak lights too.

Damn.......this amp sounds good. Among the very best I have played through.

Plugged it back again to play through it again the next morning (saturday) and nothing. It powered up, sound was coming from line out, phones and I was able to rule out cable/guitar and speaker. I had the back off and during the troubleshooting, I wiggled the speaker connections at the PC board and as I was wiggling the black one, sound came back. I noticed it started doing the same fizzy/scratchy sound at the end of notes (the very reason I took it in to have worked on in the first place), so I focused my attention on the black speaker connection at the PC board. I popped it off, re crimped it so it would have a stronger/tighter connection, and played some more. That seemed to fix it, but I thought at one point I could hear some of the fizzy/scratchy sound again, but could have been mistaken.

I was able to play through it today for a bit and there was no issue at all. Just glorious b100r sound.

I plan to continue playing through it as much as time allows and at the next band practice. So we will see how all that goes. Hopefully it holds up! I'll try to report back.

Soldering the lead to the speaker terminal is not unheard of.

 

[Michael Eisenman]

Soldering the lead to the speaker terminal is not unheard of.

Oops. I missed the part about it being the connection at the PC board. Sorry.

 

[bthiemann80]

Closing the loop on this.

I played through the amp at a rehearsal and all is good! I recorded it via line out and mic on the speaker to compare the two and it performed flawlessly. Tested it after getting it back home too and it sounds great.

Loving this amp!

 

[Hoyt]

My daughter is getting into bass guitar, so I came up with the brilliant idea of getting myself a new practice amp and gifting her my old Fender Frontman 25B that I’ve used for almost two decades. Plus, it could fill a hole in my amp collection. My main rig is a Greenboy F212 paired with a Sansamp GED 2112 preamp and Crest Prolite 2.0 power amp. It’s a bit overkill for small gigs, so I had my ears up for something that would work as a practice amp and for small gigs.

On a whim I checked the TB classifieds and stumbled across a TB’er near me who was selling a few of these in my price range.

A few dollars later and I’m now the proud owner of a B-100r USA made circa ‘99 according to the serial number.

A light cleaning later and this thing is in amazing shape for its age. The faceplate still had the protective plastic on it, the tolex is in great shape for 25+ years, and the electronics look clean. The previous owner had even used duct tape to secure the port tubes to the port flanges.

I haven’t had a chance to try my upright through it, but I’ve attached a pic of my favorite initial settings with my Precision and Jazz basses; though the longer I played it, the more I brought the bass control closer to 7.

I’ve wanted one of these since they were first released, so it’s awesome that all these years later I was finally able to get my hands on one.

I’m pretty stoked.

 

[SheaNC]

Congrats! I have had one for a several years, and I love it. The more you read about it, the more you'll notice people saying "Don't ever get rid of it!"

 

[bthiemann80]

If it is something you plan to keep around for a while, I would highly suggest getting some kind of cover for it.

Mine had some seriously scratchy pots which got cleaned but still scratch on occasion even with further cleaning as needed, and keeping a cover on it since acquisition. I suspect having the orientation of the controls (flat on top) has something to do w/ the propensity for scratchy/dirty pots.

 

[rayzak]

Nice!! Love mine still. They’re so undervalued. Enjoy!!

 

[Hoyt]

Got a set of new casters (https://www.amazon.com/gp/aw/d/B0BFXH2W9L?psc=1&ref=ppx_pop_mob_b_asin_image) with locks. The frame for the locking mechanism was hitting the rubber feet, so I cut the ends off the plastic insert bushings they come with to essentially make 4 plastic washers. Problem solved. Pic taken prior to plastic washer installation, but I figured I’d share just in case anyone else was interested or had that issue.

 

[Apex_speed]

It’s great to see this thread alive!

After owning most generations of B-15s, V4B, 69 SVT, and many other amazing Ampegs, I can’t say enough about the B-100R. It is such an underrated amp that I wish I still had!