What's happening to my 15XB?

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   Greetings all!

I suspect that this question is going to have a simple answer... But I'm hoping that I've overlooked something simple! I think I've blown my Fane, but the symptoms are irregular and mildly unpredictable. I hope it's an issue with the gain-structure/setup and my x-over clipping... Maybe someone can shed some light. I figure there's more of a conversation that could be had around the subject that might help others in a similar situation.

A little context: Took my little Sound into the garden over the weekend. One afternoon of varied listening levels whilst doing some work outside. Didn't think any of it was excessive. Reloacted the system to the usual indoors location after a couple days in the back of my car. Discovered a very new popping sound once I'd put it all back together (with the usual settings). Popping only on some notes, increased a lot with mild tweaking of the bass EQ on my mixer. But... This problem seems to become less of an issue when i turn the 
gain down on my crossover (DBX-234XL) and the power up on my amp

It gets a little confusing here. The popping and distortion sounds (to me) like processor/preamp clipping. The speaker works fine at low-medium levels. However it starts to "break up" when any harder power, or signal, is applied. As said above, this popping/distortion changes depending on the different gain settings. I do have a fair amount of experience here, certainly not a stranger to the equipment. I just feel like I'm missing something - Or I did something irresponsible!

I always run my mixer under clipping levels. I'm not a DJ and I can turn the amp up.
The Xover is normally set to 0db on the gain for the main level input. I've reduced it to-6db now and increased the amp gain.
The speaker almost sounds better at low/mid levels how it's set now. It sounded great before and never had any distortion or clipping.
I've checked all equipment/swapped out XLR's, wiggled cables, swapped channels etc - nothing there appears to be off.
Sometimes I do give it some welly... I mean why not... but I really thought I was being sensible. My money's on a recone, but considering it still plays nicely to a level, I can't help but think there could be something else. 
I tried rerouting the Bass output of the Xover back into channel 2 of the crossover and then out into the amp. Maybe a couple of days testing. No audible difference and no audible distortion or undesired sounds. 40hz high-pass always on for 1st output. Was this where I slipped up, without realising? 
Maybe a bit silly, but just in case - The room got very cold & mildly damp the other day. Left all windows open for 12 hours whilst at work. All safe, but it was freezing in the room when I got home from work, which is when this situation started.
What have I done? Have I fr*ed it? Did "doubling" the bass do something I couldn't hear? Have I always had it setup wrong? What can I do to avoid this in the future? 

Details: Possible blown driver, Fane 15XB, Matrix GT800FX. "Kam" mixer and DBX crossover. 
Running bass in a reflex cab.

Thanks to those who got this far!
And thanks to those who can help!
Ben

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Dubshot Members Profile Send Private Message Find Members Posts Add to Buddy List Registered User Joined: 01 September 2011 Location: Bournemouth Status: Offline Points: 116	Post Options Post Reply Quote Dubshot Report Post Thanks(0) Quote Reply Topic: What's happening to my 15XB? Posted: 12 May 2020 at 10:39pm
	Greetings all! I suspect that this question is going to have a simple answer... But I'm hoping that I've overlooked something simple! I think I've blown my Fane, but the symptoms are irregular and mildly unpredictable. I hope it's an issue with the gain-structure/setup and my x-over clipping... Maybe someone can shed some light. I figure there's more of a conversation that could be had around the subject that might help others in a similar situation. A little context: Took my little Sound into the garden over the weekend. One afternoon of varied listening levels whilst doing some work outside. Didn't think any of it was excessive. Reloacted the system to the usual indoors location after a couple days in the back of my car. Discovered a very new popping sound once I'd put it all back together (with the usual settings). Popping only on some notes, increased a lot with mild tweaking of the bass EQ on my mixer. But... This problem seems to become less of an issue when i turn the gain down on my crossover (DBX-234XL) and the power up on my amp It gets a little confusing here. The popping and distortion sounds (to me) like processor/preamp clipping. The speaker works fine at low-medium levels. However it starts to "break up" when any harder power, or signal, is applied. As said above, this popping/distortion changes depending on the different gain settings. I do have a fair amount of experience here, certainly not a stranger to the equipment. I just feel like I'm missing something - Or I did something irresponsible! I always run my mixer under clipping levels. I'm not a DJ and I can turn the amp up. The Xover is normally set to 0db on the gain for the main level input. I've reduced it to-6db now and increased the amp gain. The speaker almost sounds better at low/mid levels how it's set now. It sounded great before and never had any distortion or clipping. I've checked all equipment/swapped out XLR's, wiggled cables, swapped channels etc - nothing there appears to be off. Sometimes I do give it some welly... I mean why not... but I really thought I was being sensible. My money's on a recone, but considering it still plays nicely to a level, I can't help but think there could be something else. I tried rerouting the Bass output of the Xover back into channel 2 of the crossover and then out into the amp. Maybe a couple of days testing. No audible difference and no audible distortion or undesired sounds. 40hz high-pass always on for 1st output. Was this where I slipped up, without realising? Maybe a bit silly, but just in case - The room got very cold & mildly damp the other day. Left all windows open for 12 hours whilst at work. All safe, but it was freezing in the room when I got home from work, which is when this situation started. What have I done? Have I fr*ed it? Did "doubling" the bass do something I couldn't hear? Have I always had it setup wrong? What can I do to avoid this in the future? Details: Possible blown driver, Fane 15XB, Matrix GT800FX. "Kam" mixer and DBX crossover. Running bass in a reflex cab. Thanks to those who got this far! And thanks to those who can help! Ben

madboffin Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 03 July 2009 Location: Milton Keynes Status: Offline Points: 1538	Post Options Post Reply Quote madboffin Report Post Thanks(0) Quote Reply Posted: 12 May 2020 at 10:53pm
	Could be all sorts of things, first you need to spend a bit more time to ascertain for certain where the distortion is occurring, crossover, amplifier, or speaker? If it's in the speaker, first look for tears in the rear suspension. Then check if the neck joint is failing, by tapping on the cone and listening for knocking noises (difficult to explain how to do that, maybe someone has it on youtube). Check for DC offset at the outputs and inputs of the amp and xover, and look for any bad electrolytic capacitors. Otherwise it's likely to need investigation by an electronics tech with meters, oscilloscope, etc. Probaby not much help...

Meat Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 05 June 2009 Location: Manc Status: Offline Points: 1514	Post Options Post Reply Quote Meat Report Post Thanks(0) Quote Reply Posted: 13 May 2020 at 7:56am
	I had a similar amp (XT800). They were great but did some funny things when the earth wasn't right (using euro kettle through an adapter). Could be an earth thing - they interferred in ways I couldn't understand at all! Trying it on different power sockets or swapping the amp with another type might show this up.
	Don't test the champignon sound

jacethebase Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 23 September 2009 Location: Somerset Status: Offline Points: 5699	Post Options Post Reply Quote jacethebase Report Post Thanks(0) Quote Reply Posted: 13 May 2020 at 8:44am
	Get a tone generator on your phone, plug straight in to amp (no crossover) Run a sweep all across the drivers frequency’s range with the amp at a reasonable level. This will tell you what’s at fault and where. From my experience, weird issues like this normally turn out to be electronics. Caps in crossovers etc.
	www.wedding-production.co.uk www.stage2sound.com

dj jammin Members Profile Send Private Message Find Members Posts Add to Buddy List Young Croc Joined: 10 April 2010 Location: southampton Status: Offline Points: 770	Post Options Post Reply Quote dj jammin Report Post Thanks(0) Quote Reply Posted: 13 May 2020 at 11:53am
	One other thing to consider: the matrix puts out 250w at 8ohms.. the 15xb is rated 800w.. is there any chance you clipped the amp trying to get more bass out than it can deliver? In a small room I would be surprised but outdoors can be different matter as trying to get the same sound pressure with no walls etc to reflect the sound can mean your pushing things more than you realise.. Sorry to hear you got an issue with the xb..
	Reverence Sound system

Dubshot Members Profile Send Private Message Find Members Posts Add to Buddy List Registered User Joined: 01 September 2011 Location: Bournemouth Status: Offline Points: 116	Post Options Post Reply Quote Dubshot Report Post Thanks(0) Quote Reply Posted: 13 May 2020 at 2:39pm
	Thanks for the responses chaps... I'll go back to the drawing board over the next few days and experiment with these suggestions (as best I can!) - I have a spare channel on the Xover (I am running mono, using one channel of the Xover, 3 way,with a home built stereo summing circuit. I tried taking this circuit out of the mix with no change at all) So, I can see if the current channel is causing an issue. - There's a good chance that my power lead/socket is different to what it was before. Same kettle lead (UK 3pin), but maybe different socket. This kinda changes depending on how tidy I'm feeling or if I figure out a better way to route it all. No power distro at the mo - not needed really, but hadn't thought this might cause a problem. To be continued. - Jammin, there's a chance the amp went into clipping, maybe I didn't see the light in the sunshine, but I've never consciously or visibly seen the amp display a red clip light at all. I've barely seen it sit in the "solid green" setting for the signal. Normally the signal will flick into the solid green on heavy notes when I'm pushing it. I really do try my best to be careful with my kit. I suspect I'm just learning something about the setup and gain chain that I've not got my head around yet. Thanks again... I'll see if I can get some video or audio to add to the discussion. Will report back with more asap! Ben

studio45 Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 16 October 2007 Location: United Kingdom Status: Offline Points: 3864	Post Options Post Reply Quote studio45 Report Post Thanks(0) Quote Reply Posted: 13 May 2020 at 4:21pm
	Popping and distortion sounds to me like a bad connection somewhere between the amp and speaker. To troubleshoot this I would take the following steps: - Check driver for any rubbing or scratching noises when the cone is gently pressed in by hand. If there are any, the voice coil is buttered. - Take another amp, even a hifi amp, and use it to run a full-range signal through the driver. Even take it right out of the box and use wires to securely and directly connect it to the test amp, so you know that connection is good. If it sounds OK doing this, then you know the driver itself is OK. -Then try putting it back in the box and run it from the test amp. If the problem returns, it must be to do with the connection in the box or the speaker cable. Wiggle the cable to confirm this. -Then try running it from the Matrix amp full range. If the problem returns, it must be a fault with the amp, or the connection at the amp output. Wiggle the cable to confirm. - Then try putting the crossover back in the system. If the problem returns, it must be a fault in either the crossover, or the connection between the crossover and amp. Wiggle the XLR cables to determine which. Hopefully one of these steps will reveal the source of the trouble :)
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