Carvin MB15 micro bass = very noisy :(

TimBosby · #1 02-08-2013, 09:27 PM

I was very excited to get my tweed Carvin MB15 micro bass combo (200 watts). Sadly it turned out to be a disappointment. No sense in pretending...I'm not happy. It's noisier than heck. No other combo I've had (in the same room in my house, so it's not the location) has given off that much noise and picked up radio signals so strongly. I tried multiple basses (one J an one P/J) in both active and passive mode (on the amp and on the bass). Still picked up radio. My GK MB115 (which I sold, stupidly) and my Hughes & Kettner Quantum (400 watt combo) were both dead quiet in comparison... in the same room, same location, same cables, etc.

It's tiny and adorable, the tweed looks great, the tone is great too. But I don't like the noise. I guess I have 10 days to return it. Anyone else have this experience with the MB15 or other Carvin micro combos?

I shouldn't have sold my GK but I was seduced by the cuteness of tweed....

TimBosby · #2 02-08-2013, 09:52 PM

I wonder if I maybe got a dud? Can't find a bad review anywhere.

B-string · #3 02-08-2013, 09:57 PM

Sound like a problem unit, contact Carvin for a replacement/repair.

TimBosby · #4 02-08-2013, 10:00 PM

I dunno. It might be just noisy. I'm used to dead-quiet in that room. I've always considered myself lucky because some friend's houses are super noisy and amps pick up signals like crazy.

fdeck · #5 02-08-2013, 10:08 PM

If it's radio pickup, and you are not getting it with the same bass & cable on other amps, then there is something wrong with the amp. The most common cause of radio pickup is a dodgy ground connection somewhere in the input signal path, such as a bad solder joint at the input jack.

TimBosby · #6 02-08-2013, 10:11 PM

Yeah, maybe. If it's truly a problem with the amp, I don't want to have to pay to ship it back. I would hope Carvin would reimburse me.

I think you're right about the ground connection: with this amp I notice the buzz when I take my fingers off the strings. That normally doesn't happen at my house. It happens at my friend's house/practice space, but he has shoddily grounded power.

Quote:

Originally Posted by fdeck

If it's radio pickup, and you are not getting it with the same bass & cable on other amps, then there is something wrong with the amp. The most common cause of radio pickup is a dodgy ground connection somewhere in the input signal path, such as a bad solder joint at the input jack.

kreider204 · #7 02-08-2013, 10:33 PM

I think Carvin pays shipping both ways if it's within the first 30 days of purchase.

http://www.carvinservice.com/crg/home.php

craig.p · #8 02-09-2013, 04:13 AM

I agree you probably got a dud amp section. Unless the power cord is miswired -- but that's about as probable as Lemmy playing Hosanna on his next tour. Call Carvin and tell them the problem. Maybe they'll ship you a new amp plate and still give you 10 days after it arrives. It's an easy swap.

TimBosby · #9 02-09-2013, 07:13 AM

Thanks guys. I think Carvin is open on Saturdays so I'll give them a buzz today. Ideally I'd like them to send me a new one so I can compare them both side by side. If the first one indeed turns out to be way noisier than the second one, I'll ship it back on their dime.
The 10 days will probably get used up pretty quick for the first one because it'll take them about that long to put a tweed cover on the second one and ship it. But it shouldn't matter, I would hope they would take it back if it's a dud regardless.

TimBosby · #10 02-10-2013, 01:53 PM

A/Bed it today against my friend's TC Electronics combo and my own Hughes and Kettner combo (which is for sale.) The TC was a little bit noisy but not the same kind of noise... Not like ground crackle/pop. And it was quiet unless cranked. The Carvin is noisy at all volumes, has grounding crackle sounds, picks up radio signals, etc. Tried several different basses in active and passive mode too. I think I'm just going to return it and be done. I'm going to see if Carvin will send me a shipping voucher since the return is because of an actual problem and not just because I changed my mind.

1stnamebassist · #11 02-11-2013, 07:53 PM

Sorry to hear about your problems. I have the same amp with the 15' ext cab and mine is dead quiet except a bit of hum with my Danelectro bass. Sounds like you got a bad amp. They will resolve the issue without much trouble I would think.

4Banger4 · #12 02-27-2013, 06:44 PM

Hey, let us know what happens... I'm thinking about pulling the trigger on this amp.

Hope it all works out for you.

Tunaman · #13 03-08-2013, 07:30 AM

same here tim, what happened?

Carvinmanbass · #14 03-11-2013, 11:55 AM

I bought a Carvin MB12,to replace my G-K MB150S
It (the Carvin) is loud & has more power, the tone was not as good, but I did not have much time to mess with the EQ ,because the cabinet had a resonant noise on my E note (played on the A string) As well as any other E.
It (the noise) sounded like the plywood was delaminated a bit,but who knows perhaps the speaker was bad.
I sent it right back to Carvin the next day.
First impression, tone not up to par.
I also ordered mine in the tweed .
I have bought a lot from Carvin & like everything else I have bought from them.

craig.p · #15 03-12-2013, 07:36 AM

Guess what. Just for the hell of it I brought my MB15 to rehearsal last night. I'd used it in my practice space only hours before. In the middle of the rehearsal the volume suddenly dropped by about a quarter and the amp started producing some major hiss. After the position of the volume control, the position of the drive control was the major factor in how much hiss there was. Tone settings, otoh, had only a relatively minor effect on the hiss level. The frequency of the hiss had a strong mid component, so it was coming out the fifteen far more than out of the tweeter.

This morning I did a comparison with a BX250 and 115MB combination. There's almost no hiss with that setup. Hiss is still there this morning with the MB15.

Not worth the $195+shipping to swap out the amp section. Looks like this combo's gonna get converted to speaker cab only. That'll give me 2 loud+punchy and easily transportable 115 cabs.

I'll put a pointer to this in the micro bass mega thread.

Lync · #16 03-12-2013, 08:41 AM

Do you think it could be a ribbon cable situation? My BX500 cut out, dropped volume, and had static at different times before I contact cleaned it and re-seated it.

I don't have a 250, so I don't even know how the innards are set up, but just trying to help.

craig.p · #17 03-14-2013, 09:03 AM

Just did it. No dice. Put it back together and now the hiss has become a loud whistle. Doesn't matter, it was unusable anyway. But thanks for the suggestion.

BTW, I would've done the ribbon cable management a little differently than they do. And . . . I'll leave it at that.

I'll probably pull the amp off the plate again and put double sided tape over the holes, on both sides, (to seal the cab) and use one of the holes for a phone jack for speaker in.

vinxbass · #18 03-14-2013, 10:46 AM

I've had the MB15 w/ext. 1-15 cab for 4 mths now and it's very quiet, no noise at all. Sounds like you got a faulty unit, call Carvin and they'll replace it. Good luck.

craig.p · #19 03-14-2013, 07:15 PM

It's 2 years old. As I said in an earlier post, not worth the repair cost. I'm salvaging the cab+driver, the plate (for cab seal), the knobs, and various screws & nuts & standoffs for the "misc hardware" bin. The amp will go to the town's annual electronics recycling campaign.

hrodbert696 · #20 03-22-2013, 09:01 AM

Just had a hiss develop in my MB210, too, after about six weeks of use. I'll contact Carvin today and see what they can do. Drat, I really liked this combo (and sold my old one - this is all I have now!).

EDIT: never mind. It's not the amp after all - I think the hiss is somewhere in the pedalboard, maybe a bad patch cable or something. Meanwhile, though, the episode scared me enough to order a Hartke head to pair with my Carvin extension cab as an alternative rig.