Blew out the woofers on my brand new speakers, need help to find the cause

[dualazmak]

Hello friends,

A little bit to be out of the scope of this thread, but for your possible reference (and interests), I just posted on my project thread;
- Reproduction and listening/hearing/feeling sensations to 16 Hz (organ) sound with my DSP-based multichannel multi-SP-driver multi-amplifier fully active stereo audio system having big-heavy active L&R sub-woofers: #782

 

[thecheapseats]

... I contacted Wharfedale and they claim it is not covered because the speakers were "over-driven". They are offering to sell me replacement woofers for $99 each +shipping....

@ $200 to replace both speakers?... you got off easy...

 

[Gringoaudio1]

I smoked three of four drivers in a classic set of Linn Kans within hours of getting them.
I didn’t have an idiot buddy there like you did egging me on to do it so it’s all my fault.
Somehow the system volume from the computer was up and the receiver volume up enough that they blew. Welded the voice coils. Dissected the woofers after to see for myself. Dang. So glad I didn’t run that sweep on my Sonus Fabers. It was all over in a couple of seconds. No way to react and turn the volume down.

 

[dualazmak]

I smoked three of four drivers in a classic set of Linn Kans within hours of getting them.
I didn’t have an idiot buddy there like you did egging me on to do it so it’s all my fault.
Somehow the system volume from the computer was up and the receiver volume up enough that they blew. Welded the voice coils. Dissected the woofers after to see for myself. Dang. So glad I didn’t run that sweep on my Sonus Fabers.

I hope some/any of my precautions would be worthwhile for you...

 

[Gringoaudio1]

I hope some/any of my precautions would be worthwhile for you...

Thanks. I will study your power up sequence. This was a half year ago so too late to help. Drivers were glued in with some tar like substance. Ruined the baffles and grills getting the drivers out. Made new baffles and grills for some Mission woofers of similar vintage and used new Tangband tweeters from Parts Express. Reveneered the beat up boxes and used the existing crossover. All this effort entirely for appearances for when my 90 year old father visits to show him I still have and value the speakers he gave me. I’m using them as rears but with EQ using Equalizer APO they sound great as fronts. I just have too many better options for fronts.

 

[Gringoaudio1]

 

[dualazmak]

I will study your power up sequence. This was a half year ago so too late to help.

and .
Good lucks for your present and future audio system(s)!

 

[antcollinet]

Spoiler: Please just ignore the content under this Spoiler cover!

Even though I appreciate and accept your kind (joke?) message, according to the above post #48 by @antcollinet, it looks I am representing the very rare species of audiophile.

I really hope my comment did not cause any bad feeling, or make you feel attacked.

I really value ALL technical input to this hobby of ours, even if I don't always want to take it to the same level. Having said that, as a result of looking at your posts I've already started a system diagram. I doubt it will be as detailed as yours but will be useful for diagnostics.

 

[dasdoing]

I really hope my comment did not cause any bad feeling, or make you feel attacked.

I really value ALL technical input to this hobby of ours, even if I don't always want to take it to the same level. Having said that, as a result of looking at your posts I've already started a system diagram. I doubt it will be as detailed as yours but will be useful for diagnostics.

I whish his posts were more compact. Never find the hours necessary to study them

 

[dualazmak]

I really hope my comment did not cause any bad feeling, or make you feel attacked.

No, absolutely not at all!! I have been just really enjoying our frank and nice communications.
And, I know very well that I am one of the rare extreme-MCH (multichannel) species in audio community, and I am proud of it, and I am really enjoying sharing my experiences and limited knowledge with my ASR friends.

I really value ALL technical input to this hobby of ours, even if I don't always want to take it to the same level. Having said that, as a result of looking at your posts I've already started a system diagram. I doubt it will be as detailed as yours but will be useful for diagnostics.

Very nice to hear so; I feel the same as you. And I always believe one sophisticated diagram and/or one clear photo would worth more than 1,000 words.

I am, will be, more than happy if our info exchange and communication would be somewhat worthwhile reference (and of interest) for many people including all the dear ASR friends visiting this thread and others.

Let's keep enjoyable discussion and communication here on this thread and/or elsewhere in our audio community kingdom ASR Forum!


BTW, English is not my mother language as you know well. You would please let me know without any hesitation when you would find my odd wording and/or funny wrong word(s)/expressions as well as misspellings/typos. I am still very keen to improve my English writing/speaking; you and other people's frank "education/guidance" would be always indispensable since I always feel it would be almost impossible to completely/perfectly "self-proofread" my own writings.

 

[dualazmak]

I whish his posts were more compact.

Will take my efforts to be so, to do so!

 

[antcollinet]

I always feel it would be almost impossible to completely/perfectly "self-proofread"

I was just (for a bit of fun) about to tell you that "proofread" is two words. Then I looked it up and found out I was wrong.

 

[rdenney]

I was testing the installation of Dahlquist ALS-3 speakers in my RV last night, and discovered that the remote control on the sound system head unit (press the up arrow for louder and the down arrow for softer) can run away when held down a bit too long. Suddenly, I was at nearly full volume before getting my thumb over onto the turn-down button. The signal content was, I seem to recall, Dream Theater.

It blew the 1.6-amp slo-blo fuse in the right speaker. I replaced it and everything's fine again. The speakers are four ohms nominal, being driven by a 4-channel Pioneer mobile-audio amp bridge into a stereo pair. That will produce 94 watts per channel, and the speakers claim to be rated at 30 wpc RMS. I'm glad those fuses in the speakers are there. Amir blew a fuse in the when exceeding that power output with test signals, but he was using a dummy load, as opposed to me, who was just being a dummy.

Pioneer GM-D1004 4-channel Car Amplifier Review

This is a review and detailed measurements of the Pioneer GM-D1004 four (4) channel car amplifier. I purchased it after prompting by a member. It costs just $99 including Prime shipping from Amazon. I must say, I expected a piece of junk but received anything but. It is small to be sure but...

www.audiosciencereview.com

Rick "testing is dangerous" Denney

 

[Focus SE]

I am really enjoying sharing my experiences and limited knowledge with my ASR friends.

Sarcasm button fully engaged.
Your definition of the word limited is quite skewed!!!!!!!
Sarcasm button off
I truly appreciate what was contributed in this thread but using the real definition of limited, I hope to one day understand 10% of the knowledge you have provided. I have received a great deal of insight here. In a thread where plenty of opportunities to haze the OP. presented themselves, Everyone dealt with it with class and offered education. (Most of which was lost on me) here is hoping for the future!
To the OP, nojo2211, I’ll trade you two drivers for one patio door!!! Sometimes you just have to see what you got!!!

 

[multichannel_guy]

If a 20 hz test tone goes to a floorstanding speaker that's rolling off around 50hz, is it a damaging event?
I was trying to test my subwoofers with a 20hz tone and forgot to turn off the power amplifier for the stereo speakers. They received the 20hz tone.
There is no obvious damage and it appears to sound fine now, but, could there be some level of damage that is asymptomatic?

 

[sigbergaudio]

If a 20 hz test tone goes to a floorstanding speaker that's rolling off around 50hz, is it a damaging event?
I was trying to test my subwoofers with a 20hz tone and forgot to turn off the power amplifier for the stereo speakers. They received the 20hz tone.
There is no obvious damage and it appears to sound fine now, but, could there be some level of damage that is asymptomatic?

Typically not. If someone without a subwoofer watches an action movie, those speakers are likely to get 20hz content. So if the speakers are reasonably designed and you don't intentionally try to damage them by playing very low frequencies very loud, it should be fine.

 

[rdenney]

If a 20 hz test tone goes to a floorstanding speaker that's rolling off around 50hz, is it a damaging event?
I was trying to test my subwoofers with a 20hz tone and forgot to turn off the power amplifier for the stereo speakers. They received the 20hz tone.
There is no obvious damage and it appears to sound fine now, but, could there be some level of damage that is asymptomatic?

A 20-Hz tone that is not driven to amplifier clipping will probably only cause the speaker to bottom out if it goes beyond what the speaker can do, rather than frying the voice coil immediately. You'll hear the voice coil banging into the back of the frame. Turn it down!

Clipping that results in too much energy in high harmonics can burn up the voice coils in the tweeters in a hurry. As you (slowly) crank up the listening level of the test tone, listen for clipping distortion. If you hear it, turn it down!

The fundamental law of protecting loudspeakers: if it sounds bad, turn it down!

Rick "speakers can usually handle more low-frequency power than their ratings" Denney

 

[Godataloss]

Shit happens. I would just like to encourage you to protect your hearing. Your woofers are replaceable, your ears are not. I have most certainly damaged my hearing marveling at how loud I could crank my stereo when I was younger.

 

[multichannel_guy]

A 20-Hz tone that is not driven to amplifier clipping will probably only cause the speaker to bottom out if it goes beyond what the speaker can do, rather than frying the voice coil immediately. You'll hear the voice coil banging into the back of the frame. Turn it down!

Clipping that results in too much energy in high harmonics can burn up the voice coils in the tweeters in a hurry. As you (slowly) crank up the listening level of the test tone, listen for clipping distortion. If you hear it, turn it down!

The fundamental law of protecting loudspeakers: if it sounds bad, turn it down!

Rick "speakers can usually handle more low-frequency power than their ratings" Denney

Pretty sure i didn't clip anything. However, if the speaker woofer's voice coil "bottomed out" or the voice coil banged a couple of times, is that driver considered to be permanently degraded perhaps, with respect to sound fidelity? I mean, what would the average hifi enthusiast's opinion be about such a scenario?

 

[Godataloss]

Pretty sure i didn't clip anything. However, if the speaker woofer's voice coil "bottomed out" or the voice coil banged a couple of times, is that driver considered to be permanently degraded perhaps, with respect to sound fidelity? I mean, what would the average hifi enthusiast's opinion be about such a scenario?

Bottoming out is much preferred to releasing the magic smoke.