Ampeg Rocket Bass 110 strange "fan noise"

[justarookie]

Hi,

I noticed on my Ampeg RB110 amplifier that even when muted and turned up, there is a quiet, PC fan-like noise, which unfortunately also affects the recording, because I record the recordings from the DI out. The amplifier is one year old and I have never used it at too high a volume.
My question is, could this be a warranty defect? If not, is it worth having it repaired with my own money?
Thank you for the answers!

 

[eniac]

Is the noise there when nothing is plugged into the amp input(s)?

 

[justarookie]

Is the noise there when nothing is plugged into the amp input(s)?

Unfortunately, yes. Like when the PC overheats and the fan turns up.

 

[agedhorse]

It could be a defective fan or fan control circuit. You should contact Ampeg for warranty service IMO.

 

[justarookie]

It could be a defective fan or fan control circuit. You should contact Ampeg for warranty service IMO.

Thank you very much!

 

[FretRiff]

a quiet, PC fan-like noise, which unfortunately also affects the recording... could this be a warranty defect? If not, is it worth having it repaired with my own money?

I have this amp and I do not hear that noise. You should be covered under the amp's 2-year warranty (unless you bought B-stock) but you might be on the hook for the shipping expense if you don't have a local service center you can deliver it to.

 

[eniac]

I want to be sure I understand the symptoms... The noise is coming through the DI and the noise mimics the sound of a fast-running CPU fan. Is that correct?

If not, no need to read further.

If so, have you tried both positions of the DI ground-lift switch? If there's a ground-lift switch at the far end (at the interface), have you tried both positions?

Have you made any changes to the electrical system where you live, even something as simple as changing a light bulb to a different type, or adding a new lamp somewhere in the house? Have you changed any network gear recently? Did you just buy a new phone and is it close to the amp? Can you try moving the amp to a different location in the room (temporarily)? Have you tried plugging it into a different outlet that's some distance from the one you're using now? (Use an extension cord if necessary.)

What happens if you short the input signal to ground? You can do that by plugging in an instrument cable and connecting the free end's tip and sleeve together (with a paper clip held with tape or elastic band.

You might also try a different power cable, though that's probably a long shot.

 

[eniac]

Wanted to add: You might also try a different cable from the amp's DI to the interface, especially if it's one of those bargain deals.

 

[Yahboy]

Clearly shown defective. If still under shop return windows, just return it and swap with RB112, not 1 , but 2 instead. . Then stacked them up !!!

 

[doctaj]

Unfortunately, yes. Like when the PC overheats and the fan turns up.

There are no fans inside the RB110 bass amp so what you are most likely hearing is hiss/line noise. As I mentioned in another thread, I grabbed one from Sweetwater about 18mths ago and sent it because of the hiss issue. The replacement came and it was a little quieter hiss but not quiet enough to give clean recordings from the DI out. I expected some noise from the speaker as you can get from micing most amps but I thought the DI out would be a cleaner signal. Ampeg replied to my email and said it's to be expected from amps in this price range. I felt that wasn't a good answer to give a customer. LOL I searched forums and Google for a while and saw a few posts about the hiss issues. My guess is that they gained the amp level up to meet the 50watt spec and that introduced extra noise to the signal. I just kept the amp to practice with. I do wish there was a mod to lower the hiss or line noise overall but I can't find the schematics.

 

[eniac]

Just now, just for the hell of it, I went to Sweetwater's page for that amp to read the reviews. There was one review that mentioned the same symptoms the OP is hearing. I've gotten into the habit recently of reading every online review I can get my hands on before buying even something as inconsequential as a new brand of toothpaste.

https://www.sweetwater.com/store/detail/RocketB110--ampeg-rocket-bass-rb-110-1x10-inch-50-watt-bass-combo-amp/reviews?stars=2

 

[Basslie]

I have a similar issue on a Rumble 500. However, I found that when I bypass the preamp by going through the return on the fx loop, it eliminates the hiss and it is dead silent. I usually use a preamp/multi-fx pedal, so I just go into the return from that, and run DI out from the pedal too. if I find myself going direct into the amp, without that pedal, the hiss is buried in a love mix anyways. So, it may just be the way the preamp is modeled. BTW: I also went and checked several other rumbles (of various wattage) at the store, and most- but strangely not all— had a similar hiss. If I recall the ones that didn't were lower end ones. I also have a rumble 25… it has no hiss.

 

[eniac]

The lack of unit-to-unit consistency is a bad sign.

 

[agedhorse]

The lack of unit-to-unit consistency is a bad sign.

Or the greatly varying player perceptions?

 

[Basslie]

In my above mentioned rumble, if I recall, the vid was effected by the amp's EQ. It's just some noise in the preamp circuitry. It's only audible at loud volumes. Again- when bypassing the input, and going into the fx loop return, it is dead quiet. I went to the store to consider exchanging it, but after hearing the same issue on several others, I figured that's just how they are. Since it was replacing an old 80's Kustom, which was big, heavy and noisy, it didn't bother me as much.

 

[doctaj]

. . . .Again- when bypassing the input, and going into the fx loop return, it is dead quiet.

Thinking back, I've seen guitar players do this but I never asked in detail about the "why". I tent to stay out of the way as much as possible and let them get their sound how they like it before recording.
Thanks!

 

[TheDuff]

Clearly shown defective. If still under shop return windows, just return it and swap with RB112, not 1 , but 2 instead. . Then stacked them up !!!


View attachment 7379666

Yahboy has stacked 2 rb112 bass amps for more volume and low hiss. This looks like a good idea.

I was reading about theoretically stacking exactly alike amps in this way, magnifying the volume because of the stacking proximity and the way it is possible for the sound waves to sort of line up and push each other sonically. Resulting in a lot more volume than separating the two amps.

The phenomenon might be called sonic coupling.

 

[TheDuff]

There are no fans inside the RB110 bass amp so what you are most likely hearing is hiss/line noise. As I mentioned in another thread, I grabbed one from Sweetwater about 18mths ago and sent it because of the hiss issue. The replacement came and it was a little quieter hiss but not quiet enough to give clean recordings from the DI out. I expected some noise from the speaker as you can get from micing most amps but I thought the DI out would be a cleaner signal. Ampeg replied to my email and said it's to be expected from amps in this price range. I felt that wasn't a good answer to give a customer. LOL I searched forums and Google for a while and saw a few posts about the hiss issues. My guess is that they gained the amp level up to meet the 50watt spec and that introduced extra noise to the signal. I just kept the amp to practice with. I do wish there was a mod to lower the hiss or line noise overall but I can't find the schematics.

Thank you. It is very interesting to know this. I have and rb110 and an rb112.

Aside from hiss, my rb112 is head and shoulders above my rb110 in every way superior.

My rb110 at moderately high volume flubs out under heavy energetic playing finger plucking or picking. It cuts out quicker when the bass level is turned up and more energy is pushed into the amp from energetic playing or pedal sources. Speaker protection circuit is activated.

On the other hand my rb112 has never flubbed out or cut out under energetic playing or high tone control levels, or other pedals added.

So, the rb112 appears to be a much stronger and more robust amp than the rb110 from the point of view of the rocker. Not that the rb110 is a bad amp within its own limits.

 

[Yahboy]

In my above mentioned rumble, if I recall, the vid was effected by the amp's EQ. It's just some noise in the preamp circuitry. It's only audible at loud volumes. Again- when bypassing the input, and going into the fx loop return, it is dead quiet. I went to the store to consider exchanging it, but after hearing the same issue on several others, I figured that's just how they are. Since it was replacing an old 80's Kustom, which was big, heavy and noisy, it didn't bother me as much.

You should exchange with the RB112.

 

[Yahboy]

Thank you. It is very interesting to know this. I have and rb110 and an rb112.

Aside from hiss, my rb112 is head and shoulders above my rb110 in every way superior.

My rb110 at moderately high volume flubs out under heavy energetic playing finger plucking or picking. It cuts out quicker when the bass level is turned up and more energy is pushed into the amp from energetic playing or pedal sources. Speaker protection circuit is activated.

On the other hand my rb112 has never flubbed out or cut out under energetic playing or high tone control levels, or other pedals added.

So, the rb112 appears to be a much stronger and more robust amp than the rb110 from the point of view of the rocker. Not that the rb110 is a bad amp within its own limits.

Rb112 also has no problem with Low B string even volume knob at 2 o clock.

I been own and use others affordable price range 12' driver combo , like Fender Rumble V2 75/112 , V3 100/112 , Hartke KB12 , EBS Classic Session 120 , Tech 21 VT200 , RB112 are the best and comparable to Markbass CMD121P.