Gallien Krueger NEO cab problem :(

Kink Rimson · #1 08-05-2012, 10:50 AM

I recently purchased two GK NEO 2x10 cabs to go with my MB500. I've had them a couple of months now and haven't really had the chance to play them.

Well, today I hooked everything up for a test drive as I have some gigs approaching. I was very dismayed to hear a worrying buzzing, farty sound coming from the cabs when playing - almost like a ripped speaker. It wasn't overpowering but definitely noticable. It was far more apparent with the boost channel engaged, but was there on the clean chanel too if I dug in hard.

I tried each cab individually and it was the same sound from both cabs.

It did seem like the buzzing decreased as I increased volume - that or the volume just overpowered it. However I couldn't push them too hard as I was practicing at home.

For the record, I tested three different basses, both active and passive, and it was always apparent - although not as noticable when the -10db was engaged. I have also used the head through many other cabs and have never noticed the problem so I'm sure it isn't the head, and it's definitely not an inherent part of the boost sound.
Also, although I never use the horns, I turned them up full just for a test and noticed that the farty buzz came out of them too.

Is this a normal 'feature' of brand new GK cabs? I really hope they aren't faulty as I've thrown the boxes away... Starting to worry!

Foamy · #2 08-05-2012, 10:53 AM

Did you try a different head?
Is your input gain set properly on the head? Perhaps you are clipping the input?
Are you sure the sound is coming from the cab and NOT something nearby rattling?
Can you try a different instrument, like a keyboard, through it?

mtsens1 · #3 08-05-2012, 10:56 AM

I also had a problem, when I pulled off the red cap (thinking it was just for shipping) off the 1/4" jack. When using a speakon cable, and the 1/4" jack empty, it was like a air nozzle when cranking it up a bit, and made a faint farting noise like you describe. So I've since lost the red cap, so just plug a 1/4" plug in the jack.

ljazz · #4 08-05-2012, 10:58 AM

what is your preamp gain turned up to? The rb's will start to clip at the preamp once you get up around 1:00...... not sure, but it might be the same case with the mb's.

ljazz · #5 08-05-2012, 10:59 AM

Quote:

Originally Posted by mtsens1

I also had a problem, when I pulled off the red cap (thinking it was just for shipping) off the 1/4" jack. When using a speakon cable, and the 1/4" jack empty, it was like a air nozzle when cranking it up a bit, and made a faint farting noise like you describe. So I've since lost the red cap, so just plug a 1/4" plug in the jack.

I use a foam ear plug in my neo 112 and 212..... works wonders.

Kink Rimson · #6 08-05-2012, 11:18 AM

Quote:

Originally Posted by Foamy

Did you try a different head?
Is your input gain set properly on the head? Perhaps you are clipping the input?
Are you sure the sound is coming from the cab and NOT something nearby rattling?
Can you try a different instrument, like a keyboard, through it?

I don't have a spare head or keyboard to try. The noise is definitely coming from the cabs - I've tested them in two different rooms with the same result.
I didn't push the input gain past 12 o'clock. It was more apparent when the gain and boost were cranked but was still there when they were lower. It almost felt like the volume of the cabs, when cranked, started to mask the fuzzy sound.

Kink Rimson · #7 08-05-2012, 11:19 AM

Quote:

Originally Posted by mtsens1

I also had a problem, when I pulled off the red cap (thinking it was just for shipping) off the 1/4" jack. When using a speakon cable, and the 1/4" jack empty, it was like a air nozzle when cranking it up a bit, and made a faint farting noise like you describe. So I've since lost the red cap, so just plug a 1/4" plug in the jack.

I was using 1/4" speaker cables. I have also tried speakon leads, making sure the red plugs were still in place. Same sound. It's definitely coming from the front of the cab.

Kink Rimson · #8 08-05-2012, 11:20 AM

Quote:

Originally Posted by ljazz

what is your preamp gain turned up to? The rb's will start to clip at the preamp once you get up around 1:00...... not sure, but it might be the same case with the mb's.

It wasn't a clipping sound, it was still there at low volume and gain, even with the limiter engaged.

Foamy · #9 08-05-2012, 11:29 AM

OK. Hmm... Maybe it's the head then. If it were defective speaker, and the sound is the same from both cabs (4 speakers), then each should have to have the same defect to make the same noise. Not likely.
So then, the speakers are probably OK.
So, what do speakers do? They reproduce what's fed into them.
So maybe the problem is the head itself (as you've already tried different basses).
I'd try the head with somebody else's cabs. Maybe run over to your local music shop with the head to "test" out a couple new cabs. But it may be difficult to hear in there if you've got a bunch of 12-year-olds d*cking around. But that's where I'd try next.

Kink Rimson · #10 08-06-2012, 09:27 AM

Quote:

Originally Posted by Foamy

OK. Hmm... Maybe it's the head then. If it were defective speaker, and the sound is the same from both cabs (4 speakers), then each should have to have the same defect to make the same noise. Not likely.
So then, the speakers are probably OK.
So, what do speakers do? They reproduce what's fed into them.
So maybe the problem is the head itself (as you've already tried different basses).
I'd try the head with somebody else's cabs. Maybe run over to your local music shop with the head to "test" out a couple new cabs. But it may be difficult to hear in there if you've got a bunch of 12-year-olds d*cking around. But that's where I'd try next.

I can't dispute that logic, but I have already tried the amp with several different cabs and have never noticed the problem.

BrentSimons · #11 08-06-2012, 03:55 PM

Hey My Friend,
Call (Don't Email) GK they will take care of you.
Take Care,
Brent

nixdad · #12 08-06-2012, 03:59 PM

Are you sure it's not the tweeters?

Kink Rimson · #13 08-06-2012, 04:12 PM

Quote:

Originally Posted by nixdad

Are you sure it's not the tweeters?

I always have the tweeters turned right down, although I did turn them up just to test and they made the same sound.

All logic suggests it is the head that's at fault, but it's never been problematic through other cabs...

I'm testing the cabs with a Markbass head over the weekend, that should show if the cabs are to blame!

klyph · #14 08-06-2012, 04:50 PM

Do they have grilles? Have you tried them with the grilles off? If the legit bass tone can overpower the "fart" at some point, then it doesn't seem like it would be the speakers themselves. Sounds more like loose grille, loose drivers, a section of unnattached baffle, or the ultimate maddening phantom; a loose wire hitting the rear of the cone. I think it's time to bust out a screwdriver and really go over these things. I suppose if it sounds like a ripped speaker... it could actually be a ripped speaker. Sometimes small tears or ones near the center are hard to see unless you're really looking. I would do all this to save the trouble of having a tech correct something simple. If it is a speaker, thhey're much cheaper and easier to ship raw...

Joe Louvar · #15 08-06-2012, 04:50 PM

Quote:

Originally Posted by Kink Rimson

I always have the tweeters turned right down, although I did turn them up just to test and they made the same sound.

All logic suggests it is the head that's at fault, but it's never been problematic through other cabs...

I'm testing the cabs with a Markbass head over the weekend, that should show if the cabs are to blame!

Why wait - take the amp to a music store today/tomorrow and test it - the guys at most stores will help.

mouthmw · #16 08-06-2012, 04:57 PM

My GK NEO 412 sounded a bit farty (I tried many many settings on my rb700 to no avail, it was really really annoying) when it was new, but once it opened up - whoa. A lot fuller, fatter, better low end and no farting what so ever. And nothing in my chain was changed. GK Neos take a while to really open up so it could be that as well IME.

zongeek · #17 08-06-2012, 05:17 PM

I have a thread about this also.

Originally I thought it was my tweeter and turns out it's not. My NEO112 is the shops for a second time and today I lugged my whole rig to Nashville Amp Repair and played it so that they could hear the fart noise.

Almost sounds like a light fuzz not matter what you do? Or like the battery on your active bass is dying/dead?

If so, then we have the same issue. The tech thinks it's the woofer or the coils.

Here is a link to my thread: Did I just blow my tweeter? Cab trouble.

He asked me about volume also, but we then decided that volume had little or nothing to do with the issue. 4 different basses (active and passive), 3 different cabs, 4 different amps, still all goes back to the cab.

Good luck. I suggest taking the cab to an authorized repair person and going from there. As soon as the tech tells me what's wrong with mine, I will pass the info. along.

Kink Rimson · #18 08-07-2012, 05:02 PM

Quote:

Originally Posted by zongeek

I have a thread about this also.

Originally I thought it was my tweeter and turns out it's not. My NEO112 is the shops for a second time and today I lugged my whole rig to Nashville Amp Repair and played it so that they could hear the fart noise.

Almost sounds like a light fuzz not matter what you do? Or like the battery on your active bass is dying/dead?

If so, then we have the same issue. The tech thinks it's the woofer or the coils.

Here is a link to my thread: Did I just blow my tweeter? Cab trouble.

He asked me about volume also, but we then decided that volume had little or nothing to do with the issue. 4 different basses (active and passive), 3 different cabs, 4 different amps, still all goes back to the cab.

Good luck. I suggest taking the cab to an authorized repair person and going from there. As soon as the tech tells me what's wrong with mine, I will pass the info. along.

Very interesting... Maybe GK knocked out a whole bad batch? Or someone had a bad day at the factory? Both my cabs behave in exactly the same way.

Keep me posted!

RasGK · #19 08-07-2012, 05:28 PM

Hi. I had a similar issue when I first bought my Neo 410, and I realized that this farting was caused by too much lows in my EQ. I have a MB500 head, and I guess it has too much low frequency content even when the EQ is flat, or maybe the NEO series can't handle the lows that good at high volumes. I haven't tried the head with other cabs, so I cannot tell for sure. Eitherway, once I put down the low knob to around 10, and boost the lowmids around 2 to compensate, the farting practicly dissapeared. With this settings I still can get a very solid low end but without causing so much distress to the speakers. Still when I play it at loud volumes it sounds a little farty, but much less than before and it gets lost in the mix anyway, so it doesn't bother me anymore, and when I play it at mid or low volumes the fart goes away. Hope this helps.

Revmizery · #20 08-09-2012, 09:05 AM

I recently picked up a GK neo112, It had a a really bad buzzing sound coming out of it also when played. I found that the problem was actually the tweeter vibrating because the screws were not holding correctly. After unscrewing the tweeter out I noticed that one of the screws were drilled to close to the opening and you could see it kind of sticking out of the opening. Ended up using some wood glue on the holes with toothpicks to make a tight lock and now the buzzing/vibrating is gone.