Fried two subs... what am I doing wrong!? [Text View]

Tampa Tom

11-19-08, 11:08 AM

MIkeDuke

11-19-08, 11:28 AM

If those settings were accurate, 80 in the processor and 50 on the sub, there was some over lab there I think. You don't want to have what is called cascading crossovers. When you get the subs back see if they have a "Bypass" or LFE setting. If not, set the crossover as high as it can go on the sub. That way the receiver is in control of the settings. That is the only thing I can think of.

Tampa Tom

11-19-08, 11:46 AM

I had them both hooked up via LFE. I think I'm going to play with them once I get them both fixed up.

JimP

11-19-08, 11:53 AM

Looks like an engineering/manufacturing defect.

Retorically, I would ask should any sub do that?

spyboy

11-19-08, 11:57 AM

Hi everyone. I desperately need some help. I've burnt out two crossovers on two JBL sub 12s. One of them actually caught fire. I have an onkyo amplifier and the Sub crossover is at 80HZ. With the options for 100 and 120hz.

I had the settings on the back turned up a fair amount and set at what I believe was 50hz. I was watching Saving Private Ryan, made it about 4 minutes in to the beach scene and it was done for. Smoke coming out the back of it! LOL.

I have one getting serviced right now. I think the other one is a loss.

http://i38.tinypic.com/2mqw58l.jpg

If I remember correctly, JBL has had issues with the amps in their bread-and-butter 12 inch subs for close to 10 years.

Do you have a Radio Shack SPL meter? If you do, check to see what levels your settings are giving you from your sub.

If you don't have the meter, probably a good idea to get one.

Nothing that you described as far as your crossovers should make the sub electronics blow, but try what Mike Duke suggested anyway.

You may be a good candidate for a bigger, more powerful sub that can generate the levels you want without breaking a sweat.

If you were overdriving the subs, I would think you would have heard some metallic clanking when the driver bottomed out.

You might want to get both fixed, and sell them and throw in another $300-$400 for something really substanial from one of the internet direct companies like SVS, HSU, Elemental Design, Epic, etc.

MIkeDuke

11-19-08, 12:25 PM

I thought it was strange that the crossover went and not the amp. Design flaw is a possibility. I realize my cross over suggestion may be out of left field, but it may be worth a shot.

theelviscerator

11-19-08, 12:32 PM

I have a JBL ps120 I bought in 93 thats working fine, I guess at 18 years old it was made when it was still the GOOD stuff..heh..

(Now if I can just choose between all the good Small Mfrs subs out there).

MIkeDuke

11-19-08, 01:06 PM

Tampa Tom

11-19-08, 03:10 PM

It may be the amp. I have talked to someone I respect and he suggests that it is probably the amp. It could have been from just over driving the subs too much. So the plan you should follow is not to turn them up so high, or get more capable subs. Sorry :(.

LOL. No thanks. I have yet to run the two subs at the same time. The first one burnt out while I was playing some music outside and had the volume up very loud for a lengthy amount of time. I smelled the nasty smell but the subwoofer was hard as a rock. So I assume it was blown. I didn't look at the x-over but I assume since it had a slight hint of the same odor as this burnt one that it's probably suffering from the same thing. I imagine if I run them both at the same time. I won't need to turn them up as much huh?

I have an onkyo 605 with options of 80,100 and 120hz. What do you think the best setting for this would be? Thanks for taking the time to reply guys!

Triaxtremec

11-19-08, 03:33 PM

If you're using bookshelf of satellite speakers probably should set it at 120hz and if towers set to 80hz or 100hz. Remember set the crossover on the sub all the way up that way you don't have conflicting signals. Also trying setting the gain at 1/2 level on the sub and trying adjusting the gain higher on the receiver. This will help the sub run more efficiently so its not running full power all the time.

MIkeDuke

11-19-08, 03:39 PM

LOL. No thanks. I have yet to run the two subs at the same time. The first one burnt out while I was playing some music outside and had the volume up very loud for a lengthy amount of time. I smelled the nasty smell but the subwoofer was hard as a rock. So I assume it was blown. I didn't look at the x-over but I assume since it had a slight hint of the same odor as this burnt one that it's probably suffering from the same thing. I imagine if I run them both at the same time. I won't need to turn them up as much huh?

I have an onkyo 605 with options of 80,100 and 120hz. What do you think the best setting for this would be? Thanks for taking the time to reply guys!

You probably are running the subs above the limit they can handle. The amp was most likely fried.
I echo what Triaxtremec says about the crossover setting. Especially the crossover recommendation about setting it to max. Seeing we both said the same thing:D

Illah

11-19-08, 06:46 PM

Why would you set the sub crossover at 50Hz while setting the receiver at 80Hz? That essentially mean you're not playing anything between 50-80Hz. Did you just mistype that?

--Illah

JBLsound4645

11-19-08, 11:51 PM

JBLsound4645

11-20-08, 12:03 AM

kaa1954

11-20-08, 06:32 AM

Lol!

Tampa Tom

11-20-08, 02:37 PM

All I can say is that is your own fault for showing-off!

Always run a rehearsal at lower volume levels before showing-off to the neighbour I have a home theatre with a BIG sub turned why up!

I guess its time for you to install the Behreinger DCX2496 ditch the internal rubbish amplifiers that are found in these cheap AVR units and use professional power amplifiers. Run the front speakers LCR matching read my lips matching LCR arrays of surrounds lined up along the walls to surround you!

A few subs placed below the centre channel more than enough to go beyond the lowest possible rumbling soundtrack!

Ioan Allen "god damn it"
http://uk.youtube.com/watch?v=k6r5ODqM6aY

I have diy enclosure JBL 4645 loaded with JBL 2240 and in the 10 years I’ve been running it not single issue because you know why?? Because I run at lower volume levels with new films to see where it’s going in terms of peak frequency level.

If I feel it’s too much for the home that is too damn loud I’ll turn it down.

I’ve had silly amounts of low end and loudness Saving Private Ryan is one of them!

Pulse and it was load of rubbish I can’t stand it when blonde bimbos wave mobile phones in your face!!

Spiderman 3
X-Men The Last Stand
Transformers
Titanic
All the Star Wars films
All the Star Trek films

That should be enough and you know what? The JBL 4646 is still standing proudly. I’ve had the thing up to 126dbc and that was Just Bloody Loud JBL.:D

Woah buddy. Slow down there. I have to admit. I love the hell out of that towering inferno poster!!! Probably only us geeks on AVSforum would find that funny!

But honestly, I wasn't showing off to anyone. Just getting a feel for it. LOL I have to be honest with you guys. I'm in my late 20s and just kind of now really getting in to home theater. It's been a fun little thing for me for a while but before I was just using a 5.1 sony receiver and some boston CR85 bookshelves up front and boston di-poles in the rear with a JBL northridge center up until recently when I decided to upgrade. My father always loved JBLs and was in to Hi-fi and then in 98 got in to surround sound with the advent of the DVD player and analog 5.1 output.

Sorry I digressed from my point but I'm still learning. So I'm not sure exactly what you're talking about. I understand purchasing a better amp and maybe some new subs to replace the ones in the box right now. I know I want the speakers to match the ones I have now. Do you think it would be worth it to upgrade to an LC2 center? 40khz? yada yada.

spyboy

11-20-08, 02:54 PM

Woah buddy. Slow down there. I have to admit. I love the hell out of that towering inferno poster!!! Probably only us geeks on AVSforum would find that funny!

But honestly, I wasn't showing off to anyone. Just getting a feel for it. LOL I have to be honest with you guys. I'm in my late 20s and just kind of now really getting in to home theater. It's been a fun little thing for me for a while but before I was just using a 5.1 sony receiver and some boston CR85 bookshelves up front and boston di-poles in the rear with a JBL northridge center up until recently when I decided to upgrade. My father always loved JBLs and was in to Hi-fi and then in 98 got in to surround sound with the advent of the DVD player and analog 5.1 output.

Sorry I digressed from my point but I'm still learning. So I'm not sure exactly what you're talking about. I understand purchasing a better amp and maybe some new subs to replace the ones in the box right now. I know I want the speakers to match the ones I have now. Do you think it would be worth it to upgrade to an LC2 center? 40khz? yada yada.

With all due respect you should concentrate on your subwoofer situation before you start thinking about replacing any of your other speakers.

Get both subs fixed and sell them. When you have $600-$750, buy a much more substantial sub from an internet direct company. SVS, HSU, Ed, Epic, etc.

Follow the advice you have received about crossovers.

You don't need any speakers with response to 40KHZ. You would be surprised how little material there is above 10KHZ.

There isn't a good reason to try to find the limit of your subs. As long as they can deliver sufficient volume to satisfy you in your HT environment without any signs of distress, you should be fine.

Once again, you have a perfectly fine center channel speaker, but no subwoofer that works. Get your sub sitution squared away before you dwell on replacing anything else.

spyboy

11-20-08, 02:54 PM

Duplicate

Tampa Tom

11-20-08, 03:31 PM

With all due respect you should concentrate on your subwoofer situation before you start thinking about replacing any of your other speakers.

Get both subs fixed and sell them. When you have $600-$750, buy a much more substantial sub from an internet direct company. SVS, HSU, Ed, Epic, etc.

Follow the advice you have received about crossovers.

You don't need any speakers with response to 40KHZ. You would be surprised how little material there is above 10KHZ.

There isn't a good reason to try to find the limit of your subs. As long as they can deliver sufficient volume to satisfy you in your HT environment without any signs of distress, you should be fine.

Once again, you have a perfectly fine center channel speaker, but no subwoofer that works. Get your sub sitution squared away before you dwell on replacing anything else.

Sorry. I didn't really say what I have now. I have JBL Venue Stadiums at left and right. JBL Venue Voice in center. JBL Venue Monitor at surround left and right and JBL CST55s at back left and right. Also, I haven't ran the two subs together yet. It might be enough that I need to satisfy my bass urges. I bought them under $200 each shipped. I couldn't really find anything at $400 shipped that was going satisfy me like 2 300 watt 12s.

I will see how it sounds when I have them both fixed and working.

Darin

11-20-08, 03:46 PM

I guess its time for you to install the Behreinger DCX2496 ditch the internal rubbish amplifiers that are found in these cheap AVR units and use professional power amplifiers. Run the front speakers LCR matching read my lips matching LCR arrays of surrounds lined up along the walls to surround you!

He blew his sub. What do the amps feeding his mains have to do with anything?

Tampa Tom

11-20-08, 04:23 PM

He blew his sub. What do the amps feeding his mains have to do with anything?

I was kind of wondering too. I have an Onkyo tx-sr605. It's not like I bought some bargain basement brand?

JBLsound4645

11-21-08, 07:23 AM

Woah buddy. Slow down there. I have to admit. I love the hell out of that towering inferno poster!!! Probably only us geeks on AVSforum would find that funny!

But honestly, I wasn't showing off to anyone. Just getting a feel for it. LOL I have to be honest with you guys. I'm in my late 20s and just kind of now really getting in to home theater. It's been a fun little thing for me for a while but before I was just using a 5.1 sony receiver and some boston CR85 bookshelves up front and boston di-poles in the rear with a JBL northridge center up until recently when I decided to upgrade. My father always loved JBLs and was in to Hi-fi and then in 98 got in to surround sound with the advent of the DVD player and analog 5.1 output.

Sorry I digressed from my point but I'm still learning. So I'm not sure exactly what you're talking about. I understand purchasing a better amp and maybe some new subs to replace the ones in the box right now. I know I want the speakers to match the ones I have now. Do you think it would be worth it to upgrade to an LC2 center? 40khz? yada yada.

You do need a Behringer DCX2496 it’s a perfect starters to keeping peace of mind because once set-up you really shouldn’t have any more burn outs, unless (Roger Simmons) is doing the (Total Re-wring) :D otherwise you’d have no more issues.

http://www.filmdope.com/Gallery/ActorsC/2973-19898.gif

He blew his sub. What do the amps feeding his mains have to do with anything?

Everything, it has everything to do with it.

Darin

11-21-08, 07:29 AM

Everything, it has everything to do with it.

Ok. Thanks for clearing that up.

JBLsound4645

11-21-08, 07:33 AM

Also another possibility that was overlooked! Room modes, chances are you felt there wasn’t enough low end at certain frequencies and turned it up to its breaking point and overload started to slowly build up which lead to the unfortunate failure of the subs.

You don’t know which part of the beach landing, the point at which the subs burnt out, chapter and time as the opening is several chapters, I think it lasts over 20 minutes if my memory recalls.

JBLsound4645

11-21-08, 07:45 AM

Ok. Thanks for clearing that up.

The LCR, fronts have just as much low end impact as the LFE.1 the surrounds can be very unpredictable and a sudden surge of output might do speaker damage.

So yes an affordable Behringer DCX2496 will be lifesaver thou you’ll need matching amplifiers, because there’s no way around it to patch in-line with the internal cheap amplifiers, yes there cheap and nasty because you’ve got no way of telling what is happening with each channel, no barograph display and no clipping LED to warn that you’re overloading.

My Kenwood KRF-X9050D THX select dislikes the impedance on my JBL, so I tossed the internal and went with separate amplifiers, no issues, like shutting down, here the show keeps running.

I might do some frequency monitoring of (Saving Private Sub Bass) :D take a close look at what is happening on the Dolby mix, might look at the dts mix, which in some ways is different over the average A&B of Dolby and dts, there are noticeable differences.

JBLsound4645

11-21-08, 08:06 AM

Okay just started it and I see that Tamper Tom, I take it that’s (Tamper Bay, Florida) had issues 4 minutes in well lets have look at it.

Port side, stick.
Starboard side sub bass, stick.:D
Move faster and clean those mortar sub bass holes.:D

Keep the sand out of your sub bass speakers. :D
Keep those actions clear.
I’ll see you on the beach.

Darin

11-21-08, 08:16 AM

The LCR, fronts have just as much low end impact as the LFE.1 the surrounds can be very unpredictable and a sudden surge of output might do speaker damage.

Doesn't change the line level output that is being sent to the sub. The main amps have NOTHING to do with the sub. While it is theoretically possible that the LINE LEVEL stages of the receiver could be screwed up and suddenly sent a high output signal to the sub that could have overloaded it, I've never heard of that happening, and the OP should have heard that before the sub burned out. Most likely, either he's driving it beyond its capabilities, or there's something faulty with it.

JBLsound4645

11-21-08, 08:30 AM

Doesn't change the line level output that is being sent to the sub. The main amps have NOTHING to do with the sub. While it is theoretically possible that the LINE LEVEL stages of the receiver could be screwed up and suddenly sent a high output signal to the sub that could have overloaded it, I've never heard of that happening, and the OP should have heard that before the sub burned out. Most likely, either he's driving it beyond its capabilities, or there's something faulty with it.

You know I find this very queer? I have friend, that has the same film, and a really lousy Yamaha YST-SW150 sub bass and that thing makes Rice Krispies, seem quiet in the morning. Snap crackle and pop is what I hear and my friend isn’t even aware of the danger of it, I’m surprised that sub is still working, in the 9 to ten years he’s had it.

Okay I’ve taken a stopwatch timing of 4 minutes from the sound of the first mortar hitting the water as the troops near the beach landing. Started at 5 minutes 38 seconds and stopped it at 9 minutes 38 seconds bare in-mind this is region 2 DVD with 4% speed up time.

Note: that the mortars start of distant and grow deeper and louder as the (Higgins boats) draw closer to the beach. If you’re sub is playing the first mortar TOO LOUD then I pity you because there is no way its going to survive the beach landing assault.

I’ll re-run the film over, DVD again and take individual frequency graphs of the LCRS LFE.1 and see where the strongest levels of low end is, should take me an hour to do.

JBLsound4645

11-21-08, 08:46 AM

So far the left and right front is within a 30Hz range testing the centre channel now!

JBLsound4645

11-21-08, 09:02 AM

Okay tested the centre channel and again its within the 30Hz its not going below 30Hz this could be intentional by Skywalker Sound, okay time to test the surrounds!

Muted the LCR fronts via the DCX2496 so I can listen to the action on the surrounds, and its very cool being surrounded and enveloped with centre phantom effects and stereo directional effects all, at the same time.

JBLsound4645

11-21-08, 09:21 AM

Oh, this has been most interesting to re-watch with spectrumlab frequency analyzer the low end on the beach landing at best is within 30Hz a few parts are slyly sneaking below 30Hz, testing the LFE.1 now, very interesting, almost finished should take me another 30 to 40 minutes to edit the graphs.

Eskimo1

11-21-08, 09:52 AM

JBL- You do realize you're talking to yourself, right? And why in the hell would you even bother with a DD track if the disc has DTS? DTS is a VASTLY superior surround encoding method in the lossy arena.

To the OP - It seems possible that when the voice coils on your sub went poof (yes, "went poof" is a scientific term), that it had a similar effect to crossing the - and + wires, short-circuiting the amp, and could cause the small fire...

I would recommend reading up on the "subwoofer crawl" on where to position your next sub, and do buy something a little larger and more powerful.. Elemental Designs has some rather good subs for not a ton of money. If your AVR doesn't have an auto-setup feature to set the levels of your speakers, an inexpensive SPL meter will make sure you're not trying to overdrive the next sub.

Also, if your hearing is decent.. you can learn what distortion sounds like. Autosound 2000 has a CD called "My Disc" that has a music track with varying levels of distortion in them, and it'll give you an idea of what things sound like as they get distorted. I HIGHLY recommend this.

Your receiver is not a POS as a certain person in this thread (who has a serious need for ejaculating at the mouth about JBL, but I digress) might argue, but it is a receiver, and as such, packaging took precedence over other factors, so it does has its limits. Once you can hear at what point your receiver and speakers "run out of steam" (yes another highly technical term), you can set them below that level and be good to go.

JBL fanboy did have one good point though - if your system doesn't have tons of headroom to handle signals above what you're listening at, it's not a bad idea to do a run-through first. Eventually you'll find the volume setting that ensures your amp & speakers can handle anything that could be recorded in a movie.. He has to do those lower volume run-throughs he mentioned because only with eq'ing the sub to within an inch of its life, is it able to be flat down to 22hz like JBL claims..

Sorry for the long post.

JBLsound4645

11-21-08, 10:16 AM

JBL- You do realize you're talking to yourself,

No more than you….LOL:D

JBLsound4645

11-21-08, 10:18 AM

Well there’s your 4 minutes worth in detail :D unless the region 1 DVD has been re-mixed in THX Extreme to bugger sub bass speakers, then I have no idea what the heck you did, my guess is, you need a bit more practice because, the loss of two subs would at first seem unlucky. Another loss of subs would seem like carelessness.

So get a DCX2496 a few of them they don’t cost much to buy brand new. Also amplifiers and off the shelf passive sub bass speakers forget about active sub bass speakers, you need to monitor the action of the LCRS and LFE.1 though the DCX2496 and then onto the amplifiers and then lastly the loudspeakers.

Chances are that most cinemas wouldn’t have issues like this unless one of the projectionists is complete Muppet and turns the fader way up over mark 7 reference Dolby level 85db.

http://i282.photobucket.com/albums/kk279/SpectrumsubbassLFE13417/SavingPrivateRyanbeachlandingLRfron.jpg

http://i282.photobucket.com/albums/kk279/SpectrumsubbassLFE13417/SavingPrivateRyanbeachlandingLRf-1.jpg

http://i282.photobucket.com/albums/kk279/SpectrumsubbassLFE13417/SavingPrivateRyanbeachlandingcentre.jpg

http://i282.photobucket.com/albums/kk279/SpectrumsubbassLFE13417/SavingPrivateRyanbeachlandingcen-1.jpg

http://i282.photobucket.com/albums/kk279/SpectrumsubbassLFE13417/SavingPrivateRyanbeachlandingsurrou.jpg

http://i282.photobucket.com/albums/kk279/SpectrumsubbassLFE13417/SavingPrivateRyanbeachlandingsur-1.jpg

http://i282.photobucket.com/albums/kk279/SpectrumsubbassLFE13417/SavingPrivateRyanbeachlandingLFE1pa.jpg

http://i282.photobucket.com/albums/kk279/SpectrumsubbassLFE13417/SavingPrivateRyanbeachlandingLFE-1.jpg