Paradigm Esprit v3 woofer issue

[ramyarla]

Hi,

I am looking for help with finding a woofer for Paradigm Esprit v3 speaker.
Seems like Paradigm is no longer supplying parts or fixing the speakers.
Appreciate your help in locating the part.


http://www.paradigm.com/products-hidden/model=esprit-v3/page=specs

Thanks

 

[TLS Guy]

Hi,

I am looking for help with finding a woofer for Paradigm Esprit v3 speaker.
Seems like Paradigm is no longer supplying parts or fixing the speakers.
Appreciate your help in locating the part.


http://www.paradigm.com/products-hidden/model=esprit-v3/page=specs

Thanks

We get request like this often and have to break the bad news again.

You can only replace a loudspeaker driver with one of original manufacture.

This is for two reasons. Every driver has two unique features. The first is the Thiel/Small parameters. Basically these define the spring in the speaker and the weight on the end of the spring. This defines what size the cabinet has to be and the porting. Even small errors here cause drastic change in the bass response of the speaker. These parameters are like a finger print and no two drivers are alike.

The next defining feature is the acoustic response. Which in the case of a woofer, is how it rolls off and what peaks occur at break up. The response of every crossover is designed to work in tandem with the acoustic response of the drivers. The combination of the crossover slopes and driver acoustic responses must combine to flat or the speaker will sound awful. In addition drivers have different loudness with the same signal, this is their sensitivity. It is absolutely impossible to get two different drivers that will align in these three crucial areas. So if you change a driver to a different one the sound of the speaker will be drastically changed and sound awful.

Now do you have the damaged driver? If it is just the surround damaged the speaker can likely be repaired. If there are bigger problems then the speaker would need reconing. I suspect that Paradigm have no more reconing parts and that is why they can't support them any more.
In that event your only hope is finding a used driver on eBay. Failing that those speakers are at the end of the road. If you can't find a used driver, I would part out the good drivers and crossovers on eBay.

 

[ramyarla]

Thank you for the note.

The woofer in one of the speaker is not fully functional. We hear the sound little muffled.
The dealer suggested changing the woofer. I will search for used ones. I am hoping someone here may have a something in spare.

Thanks again.

 

[TLS Guy]

Thank you for the note.

The woofer in one of the speaker is not fully functional. We hear the sound little muffled.
The dealer suggested changing the woofer. I will search for used ones. I am hoping someone here may have a something in spare.

Thanks again.

So we really don't know what is the matter with that speaker. Did the dealer do any tests on the speaker, or just make this suggestion out of his thick neck supporting a neurone and synapse deficient brain?

Do you even know it is the speaker, or the electronics? If you don't know then swap the speakers over. If the fault moves with the speaker then it is the speaker. If the muffled sound stays on the same side then your electronics are at fault and the speaker blameless.

If the sound is muffled more often that not it is the tweeter that fails. If you put your ear to that speaker do you hear any sound from the tweeter?

If the surround of the woofer in that speaker looks alright it is. So then that woofer if it is the problem would have to have a voice coil/suspension problem. There aren't any other parts.
Now this is easy to test for.

Carefully put two fingers either side of the dust cap and gently push the cone in and out. See if you feel any grittiness. It should be perfectly smooth with no noise and no roughness.
If you feel roughness and or hear grating, then put the speaker on its back and see if the roughness/grating goes away. If it does then the suspension has gravitational sag causing gap rub. If that is the case, then unscrew the woofer and turn it though 180 degrees and remount it. This reverses the gravitational pull and often will correct this problem. If this is the case do the other woofer so it does not get the same problem.

If it is the speaker that is at fault, and the woofer passes the tweeter/gap rub test, then the crossover likely has a problem which can occur in older speakers.

In that case remove and take really good pictures and post them here. I will then tell you how to fault find/repair the crossover. They are pretty simple.

Report back here and be sure to tell us why and how the dealer came to recommend woofer replacement. You don't suggest woofer replacement. You give a direct order based on a firm opinion when you have determined for certain the woofer is the cause of the problem and can not be repaired.

 

[ramyarla]

Hi TLS Guy,

Thank you for the detailed analysis. I am not expert in the speaker design so I had to rely on the dealer/technician input. He suggested replacement of woofer. The technician seemed trustworthy. He has done the crossover check and pushing the speaker gently as you mentioned earlier. Initially, I dropped only one speaker and he couldn't identify the issue with his sweep tests. I dropped him the second one (that works fine) and then he was able to compare and identify the issue. The woofer seems to be moving and not completely bad but when we run the stereo tests, the lack of base is audible.

 

[TLS Guy]

Hi TLS Guy,

Thank you for the detailed analysis. I am not expert in the speaker design so I had to rely on the dealer/technician input. He suggested replacement of woofer. The technician seemed trustworthy. He has done the crossover check and pushing the speaker gently as you mentioned earlier. Initially, I dropped only one speaker and he couldn't identify the issue with his sweep tests. I dropped him the second one (that works fine) and then he was able to compare and identify the issue. The woofer seems to be moving and not completely bad but when we run the stereo tests, the lack of base is audible.

Well if that is the case then the only thing that would cause lack of output from the woofer, would be overload, that had caused voice coil damage. This can result in shorting of the turns in the voice coil with lowering of the resistance of the coil. You should be able to identify this as it drops the DC resistance of the woofer. So you can check it with an ohmmeter. If you don't have one, I suggest you buy one. Check the DC resistance of the speakers at the terminals with them disconnected from the amp. If the bad speaker reads low then that is what has happened. If they are the same I think there is a crossover problem no matter what the tech says. It is unusual for this to happen to a woofer, but I have seen it. Usually there is enough damage that gap rub is created, or the voice coil goes open circuit and then there is no output from the woofer.

If this has happened then using the speaker is likely to cause amplifier damage.

 

[ramyarla]

There is output from woofer I believe. I can see it moving. Is the crossover damage impact the amplifier?
I am scared a bit now as I just got a new Nuforce DDA that started this exercise. BTW I bought these speakers back in 2005-06 after a lot of deliberation and reading from Audioholics

 

[TLS Guy]

There is output from woofer I believe. I can see it moving. Is the crossover damage impact the amplifier?
I am scared a bit now as I just got a new Nuforce DDA that started this exercise. BTW I bought these speakers back in 2005-06 after a lot of deliberation and reading from Audioholics

The crossover problem would not likely cause trouble for the amp. I'm concerned a failing woofer would. The only possible thing that would make a woofer loose output is shorting turns in the voice coil of the woofer due to excess heat. This will lower the DC resistance of the speaker and its impedance. This could easily result in amplifier damage. You can check for this easily however by measuring the DC resistance of each speaker. If this is the issue the defective speaker will have a low DC resistance. If there is no gap rub and the DC resistance is not reduced, then I can be certain changing the woofer will not solve your problem. The crossover should be looked at much more closely.

I think a crossover issue is much more likely to be causing this issue than a woofer problem. I think most likely there is a cap that has changed value. This is especially likely if electrolytic caps have been used.

Personally with this fault I would start by recapping the crossover. This is cheap, and pretty easy to do. If the woofers both have the same DC resistance, then I would bet recapping the crossovers will restore your speakers to new condition.

 

[KenM10759]

Given the minimum 20% discount in place for trading in even a non-working Paradigm speaker for new Prestige, why not just take this opportunity to get new product with full warranty?

 

[ramyarla]

TLS Guy,

I did the resistance test. The good speaker showed the value 4.8 and the bad one showed
11.4. Seems like the resistance is not the same. This seems to contradict speaker issue.

Thanks

The crossover problem would not likely cause trouble for the amp. I'm concerned a failing woofer would. The only possible thing that would make a woofer loose output is shorting turns in the voice coil of the woofer due to excess heat. This will lower the DC resistance of the speaker and its impedance. This could easily result in amplifier damage. You can check for this easily however by measuring the DC resistance of each speaker. If this is the issue the defective speaker will have a low DC resistance. If there is no gap rub and the DC resistance is not reduced, then I can be certain changing the woofer will not solve your problem. The crossover should be looked at much more closely.

I think a crossover issue is much more likely to be causing this issue than a woofer problem. I think most likely there is a cap that has changed value. This is especially likely if electrolytic caps have been used.

Personally with this fault I would start by recapping the crossover. This is cheap, and pretty easy to do. If the woofers both have the same DC resistance, then I would bet recapping the crossovers will restore your speakers to new condition.

 

[TLS Guy]

TLS Guy,

I did the resistance test. The good speaker showed the value 4.8 and the bad one showed
11.4. Seems like the resistance is not the same. This seems to contradict speaker issue.

Thanks

Interesting. That is why you need measurements.

4.8 ohms for the DC resistance sounds right. 11.4 ohms is far too high.

I have never had a speaker voice coil increase in resistance. I think the is a bad spade connection or dry solder joint.

What you need to do now is take out the woofers and crossovers and see where the increased resistance is occurring.

First take out the woofers. If there are connected with push on spades remove them and test the DC voice coil resistance at the speaker terminals. If the bad one is still high, re solder the VC wires at the driver loudspeaker terminals. See if this solves it. If not then something strange must have happened to that woofer and I cant imagine what. When you do the re soldering job, completely unsolder the wires, and clean up the wires. These wires usually have enamel insulation. It is not uncommon for this enamel to be incompletely scraped off at the termination prior to solder and this can certainly lead to a bad connection down the road.

If the woofer is OK, then look at every connection in the signal path from the terminal on the back to the series inductor in the crossover and from the series inductor to the woofer. There would have to be a bad connection somewhere to cause this. The inductor wires are also covered in enamel and failure to scrape this off properly at the factory is also a likely cause of your problem. From the spec of your speaker there will only be one series inductor.

This is pretty simple stuff, and if you trace this methodically and go patiently you will solve it.
From what you have just reported it is much more likely than not to be a failure to properly scrape off the enamel on a copper wire before soldering, or oxidation of a spade connector.

Clean all spade connectors with tuner cleaner/electric contact cleaner before re connection.

Good luck!

 

[ramyarla]

Took the speaker to the repair tech. (suggested by the dealer). His feedback was that the >10 ohms is bit unusual for a speaker. He was able to track it to the woofer (woofer terminals show > 10 ohms). Seems like the woofer has some internal issue. His suggestion is that it is difficult to fix as is. I may have to resort to re coning. Any suggestions on the reconing and restoring it to the original fidelity? I understand that it is difficult to make it sound as original.

 

[TLS Guy]

Took the speaker to the repair tech. (suggested by the dealer). His feedback was that the >10 ohms is bit unusual for a speaker. He was able to track it to the woofer (woofer terminals show > 10 ohms). Seems like the woofer has some internal issue. His suggestion is that it is difficult to fix as is. I may have to resort to re coning. Any suggestions on the reconing and restoring it to the original fidelity? I understand that it is difficult to make it sound as original.

First of all have the tech desolder the connection of the VC wires to the terminals on the speaker chassis. Scrape the wire ends with a razor blade to make sure all the enamel has been removed. Now check the resistance right at the wires. If the resistance is correct resolder the wires to the terminals.

I still feel this has to be a dry joint. I have never had a speaker voice coil increase in resistance, and can think of absolutely no reason why it should.

If the problem can not be corrected by this repair, then reconing is actually straight forward if you are used to this sort of thing. It will return the driver to original spec. The issue is do Paradigm have reconing kits left for that driver? If they do you are home free. If not it is the end of the road for those speakers and you need to go speaker shopping.

 

[TLS Guy]

Here is a run down on speaker failure from Elliot Sound. You problem will be under section 6.

 

[ramyarla]

TLS Guy,

As per the tech. the VC gone bad. He is reconing the woofer. Just an update.
Thank you for the guidance.

 

[TLS Guy]

TLS Guy,

As per the tech. the VC gone bad. He is reconing the woofer. Just an update.
Thank you for the guidance.

Could you please ask the tech to photograph that voice coil? This is a really unusual event, as damaged voice coils go open circuit, bubble up and cause gap rub, or short the turns and lower resistance. Somehow I have to assume that there is a segment that got hot an nearly went open circuit and caused a high resistance.

One last word of advice for you. If this failure is due to heat, and most voice coil failures are, then you need either to play at a lower volume or buy a more powerful set of speakers.

Please report back, as I'm anxious to know the reason for this failure.