Issues with Hartke LH1000 + fEARful stack

[Toastfuzz]

Hey gang,

I'm struggling with some issues here. I built a stack of fEARful 12/6s last year and have been using them with a variety of amps since. Lately I picked up a Hartke LH1000 amp from a pawn shop. This combo with some overdrive in front sounds SOOO GOOD and the bridged 1000 watts easily gets me up to the volume and punch I'm looking for.

Now for the issues... last jam, after 45 minutes or so, the amp overheated and went into its emergency standby mode. 20 minutes later, it was cool enough to play for 30 minutes until it shut down again. We called it a night.

I wasnt able to contact Hartke support over Thanksgiving so another jam came around, I figured playing in 30 minute increments and letting my amp cool down in between wouldnt be TOO bad. I know not the smartest move.

Well it actually ran solid for 40 minutes or so, until I smelled a tailtell hint of burning... seconds later, my bottom cab completely died. I thought it was an issue with the amp at first, but then realized that by running it in bridged mode, I only had 1 output from the amp going to the top speaker, then daisychained to the bottom. So why would only one cab not work?

Plugged another amp into the stack and sure enough, bottom cab is toast. Tested it today and the voice coil's buzzin with a 9v test. Could the amp have caused this to happen? We were playing very loud, but those fEARfuls are supposed to be able to handle alot, no? I definitely had additional headroom at my disposal before they crapped out.

So now I'm rather concerned about plugging this Hartke into another cab, although I'd like to test it to see how it holds up... maybe if the cab was going down the drain, it overheated the Hartke more than normal? COuld the amp be fine and its just a cab issue? But the cabs have worked fine for a year, so which could it be? Amp, cab, or coincidentally both fried at once?

 

[FunkHead]

Are those 8 Ohm Cabs? Was the Hartke set to Bridge mode and was a Speakon Cable used?
I would think that if you were Daisy chained, the cabinet just couldn't handle all the power being pushed through it. It's kind of hard to fault the LH1000 based on your description of the setup.

 

[B-string]

If the voice coil was losing enamel and shorting before actually locking up or while locked up it will cause the amp to overheat. But all the fEARful boys seem to claim you can throw a 1000 watts at them no sweat? Guess that is wrong.
Disconnect the burned cab and the amp might still be fine as it was trying to protect itself from the cooked cab.

 

[CL400Peavey]

Have you run the amp with any other cabs hard? There is clearly an issue with your amp, crossover, or there was a flaw in the voice coil of the woofer. I would start trouble shooting piece by piece. Swap the cross over into the working cab, see if that presents an issue at low power with a different amp. Get your amp checked out, and get your woofer repaired.

All I know is that I have had a B1500 cranked hard into my cabs, and have not had an issue.

 

[B-string]

Have you run the amp with any other cabs hard? There is clearly an issue with your amp, crossover, or there was a flaw in the voice coil of the amp. I would start trouble shooting piece by piece. Swap the cross over into the working cab, see if that presents an issue at low power with a different amp. Get your amp checked out, and get your woofer repaired.

All I know is that I have had a B1500 cranked hard into my cabs, and have not had an issue.

Amps don't have voice coils. If the amp was the issue both cabs would have fried IME. A crossover swap couldn't hurt if the woofer is low passed.

 

[BurningSkies]

If the voice coil was losing enamel and shorting before actually locking up or while locked up it will cause the amp to overheat. But all the fEARful boys seem to claim you can throw a 1000 watts at them no sweat? Guess that is wrong.
Disconnect the burned cab and the amp might still be fine as it was trying to protect itself from the cooked cab.

Yeah, there's something else going on here. The LH1000 is 1000w bridged at 4ohms, so that's 500w per cab. I've been hitting my setup with way more than that regularly for over two years.

 

[MattyH]

Unbridge it!

I never run mine bridged and I never have to go past 2-3 on my LH1000. And I play 200-500 person parties on large stages 2-4 times a week. Could you be pushing toooo much?

Also, I just had my LH1000 serviced. Apparently the soldering jobs throughout the entire machine aren't the best. Maybe something is loose and causing you a problem. But I agree with NYCbassist. In my 4 year experience with the LH1000 I've never overheated anything while unbridged.

 

[CL400Peavey]

Amps don't have voice coils. If the amp was the issue both cabs would have fried IME. A crossover swap couldn't hurt if the woofer is low passed.

Yep. I was fat finger posting/editing from a smart phone and mis typed.

 

[BurningSkies]

Amps don't have voice coils. If the amp was the issue both cabs would have fried IME. A crossover swap couldn't hurt if the woofer is low passed.

A traditional 15sub should have a low pass around 800hz. The one that is spec'ed for that cab if built correctly should be burly enough to handle the wattages we're discussing. In fact, they're over-spec'ed.

 

[wcriley]

I'm with B-String. The problem is most likely in the speaker cabinet. (Or, possibly, the cable going to it.)

I recently found a stray strand of wire in one of my 12/6s that had shorted across a Speakon jack, throwing my amp into protect.

The smell of burnt enamel usually lingers for a while. Sniff the back of the woofer. They're robust, but not completely indestructable.

If something shorted in the crossover, you might be able to see burnt components.

 

[Toastfuzz]

Are those 8 Ohm Cabs? Was the Hartke set to Bridge mode and was a Speakon Cable used?
I would think that if you were Daisy chained, the cabinet just couldn't handle all the power being pushed through it. It's kind of hard to fault the LH1000 based on your description of the setup.

Yep thats the exact setup, amp at Bridged mode, amp -> speakon to cab -> speaker cable to other cab. Total load of 4 ohms, just what the Hartke likes.

If the voice coil was losing enamel and shorting before actually locking up or while locked up it will cause the amp to overheat. But all the fEARful boys seem to claim you can throw a 1000 watts at them no sweat?

This has merit... its hard to say how long I played through them with one of the drivers farting out. When the bottom cab died, the top cab was still playing (I turned everything off immediately) but there was a distinct burning plastic smell that eminated from the rig then... when I pulled the driver from the cab, I was hit with a wave of the same smell. Its the speaker.

No visible issues with the crossover boards, although I didnt remove them fully

Have you run the amp with any other cabs hard? There is clearly an issue with your amp, crossover, or there was a flaw in the voice coil of the woofer. I would start trouble shooting piece by piece. Swap the cross over into the working cab, see if that presents an issue at low power with a different amp. Get your amp checked out, and get your woofer repaired.

All I know is that I have had a B1500 cranked hard into my cabs, and have not had an issue.

I havent, for fear of blowing my 2x15 in a similar fashion. I fear the blown voice coil could be a red herring (as in, could something in the amp have caused the voice coil to blow?) My only reasoning here is the cabs never showed any issue with other amps, but then again they've never been hit with quite so much power either.

Also leary on swapping the crossover into the working cab, as it worked seemingly fine in this cab until the speaker blew. But in those 12/6's I'm not sure I could distinguish the 12 from the 6 enough to tell if the crossover is "working."

Flaw in the woofer voice coil is what I'm hoping for now.

If the amp was the issue both cabs would have fried IME. A crossover swap couldn't hurt if the woofer is low passed.

This has merit... it makes me think perhaps the amp isn't at fault? Maybe I should drag out the 2x15 and put it through its paces? I'd hate to spend another $120 on 15" drivers just to re-prove that my amp's broken.

Unbridge it!

I never run mine bridged and I never have to go past 2-3 on my LH1000. And I play 200-500 person parties on large stages 2-4 times a week. Could you be pushing toooo much?

Also, I just had my LH1000 serviced. Apparently the soldering jobs throughout the entire machine aren't the best. Maybe something is loose and causing you a problem. But I agree with NYCbassist. In my 4 year experience with the LH1000 I've never overheated anything while unbridged.

If you're playing large stages 4 times per week, you're only getting 250 watts per gig! I dont know how you can be heard at 2-3 volume!

But in all seriousness, I'm not mic'd and going into a PA, and I play loud music. I bought the head because I had cabs that can (should?) take 1000 watts with ease.

+++++

In conclusion, I'm thinking the blown voice coil is to blame for my issues. If it was on its way out, that could explain why my amp overheated last time. The amp didnt overheat this time before the coil fried completely. I'm going to try playing the amp through my 2x15 for an hour or two to see how hot it gets... hate risking my last working cab but I really like the sound and functions of this amp. If the Hartke runs the 2x15 and stays cool then I'll know it was the speaker's fault my amp got so hot.

These fEARfuls sound nice but they've been a huge pain in my ass so far. Hard to say if I go through with fixing them or selling the remaining working components and finding another 2x15. Back to the basics!

 

[FunkHead]

Unbridge it!

I never run mine bridged and I never have to go past 2-3 on my LH1000. And I play 200-500 person parties on large stages 2-4 times a week. Could you be pushing toooo much?

Also, I just had my LH1000 serviced. Apparently the soldering jobs throughout the entire machine aren't the best. Maybe something is loose and causing you a problem. But I agree with NYCbassist. In my 4 year experience with the LH1000 I've never overheated anything while unbridged.

I also run in dual parallel mode. Using two 4 ohm cabs, I have 320 watts available to each cab. The volume knob is at 2 with my Ric and 3 with my Steve Harris at gigs. It's probably about maybe 75 watts to each cab and way way loud enough. I'm talking stage volume here. Any louder and it would be unbearable on stage. Honestly Bridging through 2 12's would scare me no matter how good those 12's are.

 

[mbelue]

The amp gong into shutdown sounds like when I blew my capacitor in my fearful crossover.
You really oughta crack open the cabinet and poke around. Blown caps are real obvious.
The cab might still produce a weak farty sound from the 6, mine did.
My new capacitor is just fine with ~700 Watts.

 

[songwriter21]

I say screw those cabs, and go with a better-known, and more reliable company. Time and time again, I'm AMAZED by the huge tone and portability of Markbass. I'm not a fan of their amps, but their cabs can handle some serious heft. My goofy little Traveler 2x10 always makes me laugh at the volume it can dish out, stupifying other musicians, and especially bassists. I also have beaten the crap out of it, playing aggressively at times, and getting thrown in and out of the trailer from countless shows.

The owner of the company, Marco ? (forget the last name), couldn't be nicer. I met him and his reps at NAMM a few years back, was interested in buying a Markstand, and he said (with heavy Italian accent), "No, no, you take, from one bass player to another." Yep, free of charge, so that sold me right there.

 

[mbelue]

I say screw those cabs, and go with a better-known, and more reliable company. Time and time again, I'm AMAZED by the huge tone and portability of Markbass. I'm not a fan of their amps, but their cabs can handle some serious heft. My goofy little Traveler 2x10 always makes me laugh at the volume it can dish out, stupifying other musicians, and especially bassists.

I don't think a 2x10 is anywhere near the level of volume the OP is referring to. Markbass does have cute little stuff though.

 

[songwriter21]

Oh hell, I didn't mean for him, but their big cabs. I was simply saying that just what one of their little cabs can do.

 

[BurningSkies]

I've played both Markbass and fEARful cabs. Nowhere close in volume or tone.

 

[Lonnybass]

I've played both Markbass and fEARful cabs. Nowhere close in volume or tone.

+1.

 

[Toastfuzz]

I also run in dual parallel mode. Using two 4 ohm cabs, I have 320 watts available to each cab. The volume knob is at 2 with my Ric and 3 with my Steve Harris at gigs. It's probably about maybe 75 watts to each cab and way way loud enough. I'm talking stage volume here. Any louder and it would be unbearable on stage. Honestly Bridging through 2 12's would scare me no matter how good those 12's are.

Thats fine and dandy, but this isn't a question of whether I'm playing too loud, its a question of why my amp + cabs aren't operating at the capacity for which they were designed (and for which I bought them!)

The amp gong into shutdown sounds like when I blew my capacitor in my fearful crossover.
You really oughta crack open the cabinet and poke around. Blown caps are real obvious.
The cab might still produce a weak farty sound from the 6, mine did.
My new capacitor is just fine with ~700 Watts.

Great suggestion, I will check the crossover first thing. Thats the one part of the build I wasnt 100% confident in (I bought the crossovers pre-wired but they looked alittle off... I wasn't at all happy with my order from speakerhardware.com, wouldnt surprise me if they sold me a bunk xover too

I say screw those cabs, and go with a better-known, and more reliable company.

Not a terrible suggestion. Although we seem to have very different needs.... I'd be replacing my 12/6 stack with a pair of 2x15's if it came to that.

While I get "my tone" in the high mids and treble from playing an old Rickenbacker into a variety of drive pedals, what I really needed the fEARfuls and Hartke for is the BASS. That rattle-your-pupils kick-you-in-the-chest bass that my drummer and guitarist can feel from across the room. We found we can't improvise successfully unless the guitars/vocals are HEARD and the bass/drums are FELT. I guess I wasn't so clear on my needs at first, but this is the reason I dont want to unbridge the amp or downgrade to a small cab or single cab.

The fEARfuls live up to their hype, I would have never expected to get that epic FELT bass out of a small stack with two 12"s and two 6"s. The only rig I've played through that could equate to that was when I ran a pair of 2x15's. So ideally I'd like to get my fEARfuls in order, if for nothing else, to save my back and save some space.

 

[FunkHead]

Thats fine and dandy, but this isn't a question of whether I'm playing too loud, its a question of why my amp + cabs aren't operating at the capacity for which they were designed (and for which I bought them!).......

I'm with ya'. The weird thing is that the top Cab held up fine. If the 12's are identical,then either the fried one was defective or as suggested above, maybe a Cap or X-over is to blame. I'm not sure how much power you were putting through it but I highly doubt you were anywhere near max. That's why I referenced about 75 watts per Cabinet with my setup.
Edit: I am in no way suggesting you ditch your setup. I think you have a good start to figuring out what went wrong with your Cab. Maybe the best thing to do is slap a "cheap" but very powerful 12 back in it for test purposes. That way you can see how the LH1000 does. If the 12" holds up then you know the X-over etc... is okay.