Trouble with Bowers and Wilkins 804 D3

T

Turk

Junior Audioholic
I would not mix the Grotto and SVS sub. The SVS sub will be a lot more powerful. Use the SVS sub and get rid of the Grotto, you generally do not want to mix subwoofers with very different dynamic range abilities.

Cancel your Audioquest bi wire cable order. That isn't going to help you. If anything, Bi-amping will make it worse.
Do you think the new svs 4000 series that is replacing the 13 ultra would work well with the 16 ultra? Unfortunately my room setup will not hold another 16 ultra.
 
S

shadyJ

Speaker of the House
Staff member
Do you think the new svs 4000 series that is replacing the 13 ultra would work well with the 16 ultra? Unfortunately my room setup will not hold another 16 ultra.
I think the answer is "kind of." The big difference between them will be the low end. The SB16 will be able to play louder at lower frequencies with less distortion. I think if your room is not large, they should play well together. You might want to apply a slightly more aggressive high pass filter on the Sb13 to ensure that it doesn't run into distortion in an attempt to keep up with the SB16.
 
T

Turk

Junior Audioholic
I think the answer is "kind of." The big difference between them will be the low end. The SB16 will be able to play louder at lower frequencies with less distortion. I think if your room is not large, they should play well together. You might want to apply a slightly more aggressive high pass filter on the Sb13 to ensure that it doesn't run into distortion in an attempt to keep up with the SB16.
Thanks I’ll give that a shot
 
S

Scully80

Audiophyte
I’m having trouble with the lower 2 woofers rattling on my b&w 804 D3. I already replaced my first pair that I had for about 2 months and now this pair is doing the same thing after only 1 month. Does anyone have any idea on what could be causing this issue? My equipment is a 11.2 set up used mainly for movies but I also listen to music often. I have a furman reference 20i power conditioner, marantz 8012, but run my main 5 speakers off of a rotel rmb-1585. I do like to listen to my movies pretty loud, volume setting at about 80-83 out of about 98 max. I would think that these speakers could Handel this amount of volume but maybe I’m wrong. I have owned motion 40 and definitive technology towers in the past and I have never had this issue before. The second time around I even kept the crossover at 60-80hz trying to keep most of the bass on the subwoofers but this didn’t help. Has anyone ever heard of this or have any suggestions on how to correct this so it won’t happen a 3rd time?
Having the same issue with my 804D3s. Bought these for home theater and music use. Found that I could crank them up pretty loud for most genres of music with out any issues (classic rock, pop, alternative, etc...). However, for home theater and music with deep bass such as hip hip or rap, it seems I have overextended the 2 lower mids (dark grey) as they rattle and now cause distortion. When I put my ear up close, I can tell they are no longer functioning property as they are likely damaged. Even though they do not rattle at lower volumes, they still sound like they are damaged or there is an issue with them.
 
T

Turk

Junior Audioholic
Having the same issue with my 804D3s. Bought these for home theater and music use. Found that I could crank them up pretty loud for most genres of music with out any issues (classic rock, pop, alternative, etc...). However, for home theater and music with deep bass such as hip hip or rap, it seems I have overextended the 2 lower mids (dark grey) as they rattle and now cause distortion. When I put my ear up close, I can tell they are no longer functioning property as they are likely damaged. Even though they do not rattle at lower volumes, they still sound like they are damaged or there is an issue with them.
It will only get worse with the rattling. My new bass units should be in this week so I’m going to change my crossover to 90 this time. I did get everything tested and there is not any clipping issue. What do you have your cross over at? What kind of subs are you using?
 
TLS Guy

TLS Guy

Seriously, I have no life.
So now we have to member reporting this problem.

I think you both have the wrong speakers for your application. I don't think a sub setting at 90 Hz will solve your problem. Only drastically reducing the volume you play them at will.

Here is why. I have taken a closer look at the problem.

These speakers only have 6.5 inch woofers, yet the F3 is 24 Hz. Now there is ALWAYS in inverse relationship between bass extension and efficiency.

Now the lack if efficiency is hidden by the sensitivity spec of 2.83 volt one meter. Now Home theater magazine measured the sensitivity at 86.4 db 2.83 volts 1 meter and not the specified 89 db 2.83 volts 1 meter.

However they also measured the impedance of the speakers and got this.


At around 100 Hz the impedance is 2.4 ohms and does not even rise to 4 ohms until 500 Hz. This is the range where all the power of music is, not in sub range. In sub range the impedance is actually quite high due to the tuning peaks.

So in fact if you take this data and recalculate sensitivity at 1 watt 1 meter, then these speakers are in fact only 80 db 1 watt 1 meter. What this means is that these voice coils will be taking huge amounts of power in the 100 Hz to 500 Hz range, and therefore heating.

Now a sub will only help prevent woofer failure if the failure is due to over excursion. If it is thermal damage a subs ability to prevent damage is minimal.

Now this is a picture of the cone VC former and coil from the B & W site.


The notable feature is that the VC former is very long and the coil wound right to the lower edge of the former. So this VC is deep in the speaker pole gap, what is known as under slung. This I'm sure has been done for linearity, I'm certain, given the enormous excursion that will be required of these woofers to have an F3 of 24 Hz! The downside is increased heat build up.

So I would have a very high degree of confidence indeed that both of you are over heating the voice coils and the lower turns are coming loose and dropping into the pole gap and causing your problem. Given the design of the VC former I feel it is highly unlikely that the VC former is leaving the pole gap, and casing mechanical damage.

Your solutions are: -

1). Turn the volume down a lot.

2). Change your choice of program and in particular avoid dub step and may be try Mozart, Beethoven, Bach etc. These are British designed speakers and will be primarily designed with the classical music lover in mind.

3). If you are using Audyssey Dynamic Eq, turn it off, as it adds a crazy and unpleasant bass boost.

Your only other option is to change to cruder and more robust speakers.
 
S

Scully80

Audiophyte
2). Change your choice of program and in particular avoid dub step and may be try Mozart, Beethoven, Bach etc. These are British designed speakers and will be primarily designed with the classical music lover in mind.

Your only other option is to change to cruder and more robust speakers.
Agreed on the above. Listening to Eric Clapton, Elton John, and Pink Floyd at high volume these speakers are the best listening experience I have come across, with no rattling. Listening to Elton John classic hits right now and no rattling or distortion whatsoever. My music listening genre is pretty wide, that is my only disappointment with these speakers.
 
TLS Guy

TLS Guy

Seriously, I have no life.
Agreed on the above. Listening to Eric Clapton, Elton John, and Pink Floyd at high volume these speakers are the best listening experience I have come across, with no rattling. Listening to Elton John classic hits right now and no rattling or distortion whatsoever. My music listening genre is pretty wide, that is my only disappointment with these speakers.
May be if you would both take this young Lady's advice you would not blow up so many speakers.


Sir Simon Rattle outgoing principle conductor of the Berlin Phliharmonic Orchestra, and now the principle conductor of the LSO has placed her on his very short list of greatest living composers. So listen up, she gives very good advice.
 
Bucknekked

Bucknekked

Audioholic Samurai
May be if you would both take this young Lady's advice you would not blow up so many speakers.


Sir Simon Rattle outgoing principle conductor of the Berlin Phliharmonic Orchestra, and now the principle conductor of the LSO has placed her on his very short list of greatest living composers. So listen up, she gives very good advice.
It makes my heart glad that such people exist in the world. What a marvelous young woman.
I watched the whole video. An accomplishment for me.
I will still love my old fashioned rock n roll, but knowing she exists and is trying to make the world a more beautiful place through her music somehow makes me smile.
Thanks for the wonderful video.
 
T

Turk

Junior Audioholic
IMG_2915.JPG
So now we have to member reporting this problem.

I think you both have the wrong speakers for your application. I don't think a sub setting at 90 Hz will solve your problem. Only drastically reducing the volume you play them at will.

Here is why. I have taken a closer look at the problem.

These speakers only have 6.5 inch woofers, yet the F3 is 24 Hz. Now there is ALWAYS in inverse relationship between bass extension and efficiency.

Now the lack if efficiency is hidden by the sensitivity spec of 2.83 volt one meter. Now Home theater magazine measured the sensitivity at 86.4 db 2.83 volts 1 meter and not the specified 89 db 2.83 volts 1 meter.

However they also measured the impedance of the speakers and got this.


At around 100 Hz the impedance is 2.4 ohms and does not even rise to 4 ohms until 500 Hz. This is the range where all the power of music is, not in sub range. In sub range the impedance is actually quite high due to the tuning peaks.

So in fact if you take this data and recalculate sensitivity at 1 watt 1 meter, then these speakers are in fact only 80 db 1 watt 1 meter. What this means is that these voice coils will be taking huge amounts of power in the 100 Hz to 500 Hz range, and therefore heating.

Now a sub will only help prevent woofer failure if the failure is due to over excursion. If it is thermal damage a subs ability to prevent damage is minimal.

Now this is a picture of the cone VC former and coil from the B & W site.


The notable feature is that the VC former is very long and the coil wound right to the lower edge of the former. So this VC is deep in the speaker pole gap, what is known as under slung. This I'm sure has been done for linearity, I'm certain, given the enormous excursion that will be required of these woofers to have an F3 of 24 Hz! The downside is increased heat build up.

So I would have a very high degree of confidence indeed that both of you are over heating the voice coils and the lower turns are coming loose and dropping into the pole gap and causing your problem. Given the design of the VC former I feel it is highly unlikely that the VC former is leaving the pole gap, and casing mechanical damage.

Your solutions are: -

1). Turn the volume down a lot.

2). Change your choice of program and in particular avoid dub step and may be try Mozart, Beethoven, Bach etc. These are British designed speakers and will be primarily designed with the classical music lover in mind.

3). If you are using Audyssey Dynamic Eq, turn it off, as it adds a crazy and unpleasant bass boost.

Your only other option is to change to cruder and more robust speakers.
I just pulled out the bad woofers and as you can see in the picture above the part that is failing is the glue that holds that yellow part onto the coil. Do you think this is still from it heating up? I never have any problems with music listening it seems to happen with movies.
 

Attachments

A

Andrein

Senior Audioholic
Wondering why I dont have problems with my ProAcs 148 crossed over at 60hz, having each 2x6.5 woofers at similar spl. There are lots of 2x6.5 speakers which dont have any issues in this situation. Can there be some design issue with 804?
 
Patrick Butler

Patrick Butler

Junior Audioholic
Hi Turk,

Sorry to hear that you are having issues. I’ve spent a considerable amount of time hammering 804D3s with a Rotel RB-1590, and they sailed through the music. That said, you’ve got a problem, and I’d like to help out. PM me, and we’ll get this resolved.

Best regards,

Patrick Butler
Bowers & Wilkins

I’m having trouble with the lower 2 woofers rattling on my b&w 804 D3. I already replaced my first pair that I had for about 2 months and now this pair is doing the same thing after only 1 month. Does anyone have any idea on what could be causing this issue? My equipment is a 11.2 set up used mainly for movies but I also listen to music often. I have a furman reference 20i power conditioner, marantz 8012, but run my main 5 speakers off of a rotel rmb-1585. I do like to listen to my movies pretty loud, volume setting at about 80-83 out of about 98 max. I would think that these speakers could Handel this amount of volume but maybe I’m wrong. I have owned motion 40 and definitive technology towers in the past and I have never had this issue before. The second time around I even kept the crossover at 60-80hz trying to keep most of the bass on the subwoofers but this didn’t help. Has anyone ever heard of this or have any suggestions on how to correct this so it won’t happen a 3rd time?
 
T

Turk

Junior Audioholic
Wondering why I dont have problems with my ProAcs 148 crossed over at 60hz, having each 2x6.5 woofers at similar spl. There are lots of 2x6.5 speakers which dont have any issues in this situation. Can there be some design issue with 804?
Might be I have had 8 of them tear in the same way.

If you watch the video up above maybe they self destruct when they play “ugly music”...?
 
KenM10759

KenM10759

Audioholic Samurai
I have to wonder if the crossover set isn't actually being applied and the speakers are trying to accomplish 14hz output. Something is amiss with a woofer coming apart like that on new design speakers. Bowers & Wilkins has been around a long time and know how to make good drivers. I just can't fathom how 8 of them would fail in this way. Unreal.
 
TLS Guy

TLS Guy

Seriously, I have no life.
View attachment 23585

I just pulled out the bad woofers and as you can see in the picture above the part that is failing is the glue that holds that yellow part onto the coil. Do you think this is still from it heating up? I never have any problems with music listening it seems to happen with movies.
That is an interesting photograph. It looks to me as if the adhesive held, but the cone tore away from the VC former. These cones are two layers of a carbon fiber with foam sandwiched between them. You can clearly see the torn and shredded foam.

This is most likely mechanical damage, but could be a combination with heat as well, if the VC former heated up enough to make the cone loose integrity at that point. Given the actual true sensitivity/efficiency of these speakers, I would expect a lot of VC heating if driven hard from a powerful amp. It would be interesting to see if the VC is discolored in any way.

This likely is a limitation of the design concept, which is fundamentally building a speaker with 6.5" drivers that has a 3db point of 24 Hz. This is attractive in Europoe, as using subs is not popular for multiple reasons. I bet if you played classical and jazz in most European sized rooms, they would sound excellent and you would have no need of a sub. Get it in North America and you have larger space and a penchant for ugly dynamically compressed music.

When I was involved with Jordan Watts back in the seventies, we had a very low incidence of failure across Europe and the Far East. Many are still working perfectly after half a century. Then export to Canada started. When I took over from the first importer, I inherited a vast number of blown drivers. I think I must have rebuilt every driver sent to Canada. After that we vowed to avoid the US altogether. North American users have a habit of using refined domestic speakers as pro PA stage/instrument speakers. Basically I suspect the speakers are fine, but North Americans have no sense of how to use a refined domestic speaker.

In any case when you get new drivers, you need to play at a lower volume in future. Listen to Alma!
 
T

Turk

Junior Audioholic
I could hear both times when the speakers failed. The first time was during a movie where a group of people started banging on large drums before a war scene, the second time was when a spaceship flew overhead and the rumble from the engines took out the speakers. It doesn’t seem to happen at all when I’m listening to music. They work fine for everything from classical, country, rock, metal, pop, edm, and your dub step. They are a very detailed speaker and make every genre of music exciting to listen to. Unfortunately I’m not having any luck with movies which accounts for 90% of what I use them for.
 
TLS Guy

TLS Guy

Seriously, I have no life.
I could hear both times when the speakers failed. The first time was during a movie where a group of people started banging on large drums before a war scene, the second time was when a spaceship flew overhead and the rumble from the engines took out the speakers. It doesn’t seem to happen at all when I’m listening to music. They work fine for everything from classical, country, rock, metal, pop, edm, and your dub step. They are a very detailed speaker and make every genre of music exciting to listen to. Unfortunately I’m not having any luck with movies which accounts for 90% of what I use them for.
Interesting. Do you by any chance have the speakers set to LFE + Main? If not the LFE should all go to the sub. If all the LFE was going to the sub then you will have to cross the speakers at 250 Hz for movies.

Your best solution when you get the new drivers, is to get two good subs that have good performance to 250 Hz. Put a sub each side of the the 804 D3s and set the cross to 250 Hz. Given what has happened, I would not play loud rock and especially not dub step through them without a high cross. Just because the final coup de grace came in a movie, does not mean other program did not set the drivers up for final failure.
 
highfigh

highfigh

Seriously, I have no life.
That is an interesting photograph. It looks to me as if the adhesive held, but the cone tore away from the VC former. These cones are two layers of a carbon fiber with foam sandwiched between them. You can clearly see the torn and shredded foam.

This is most likely mechanical damage, but could be a combination with heat as well, if the VC former heated up enough to make the cone loose integrity at that point. Given the actual true sensitivity/efficiency of these speakers, I would expect a lot of VC heating if driven hard from a powerful amp. It would be interesting to see if the VC is discolored in any way.

This likely is a limitation of the design concept, which is fundamentally building a speaker with 6.5" drivers that has a 3db point of 24 Hz. This is attractive in Europoe, as using subs is not popular for multiple reasons. I bet if you played classical and jazz in most European sized rooms, they would sound excellent and you would have no need of a sub. Get it in North America and you have larger space and a penchant for ugly dynamically compressed music.

When I was involved with Jordan Watts back in the seventies, we had a very low incidence of failure across Europe and the Far East. Many are still working perfectly after half a century. Then export to Canada started. When I took over from the first importer, I inherited a vast number of blown drivers. I think I must have rebuilt every driver sent to Canada. After that we vowed to avoid the US altogether. North American users have a habit of using refined domestic speakers as pro PA stage/instrument speakers. Basically I suspect the speakers are fine, but North Americans have no sense of how to use a refined domestic speaker.

In any case when you get new drivers, you need to play at a lower volume in future. Listen to Alma!
That didn't separate from the cone, it separated from the spider and that would be due to over-excursion. If the VC doesn't rub, this is likely a case of the speakers being driven hard plus equalization- the best combination for killing woofers, especially small ones.

Your decision to avoid the US- there's a problem here where the favorite word for many people is 'more'. Also, there's a problem with manufacturers stating that their products will do things they can't, such as produce 20Hz (shown as 'Frequency Range') or 24Hz (shown in the D3 specs with +/- 3dB from reference axis). Under controlled conditions, sure, but this isn't a real world spec and they shouldn't make people believe these speakers will produce the needed energy in that range when they're using 6.5" drivers. If Audussey was used and the mic happened to be in a null, this is easily the result of that and I'd like to see the response curve AND EQ settings.

The impedance of the woofer at 20Hz is about 20 Ohms, so I think the over-excursion was caused by boosting a higher frequency.

In engineering, this would fall under 'application error'- these speakers are being used for something other than what they were designed. Everything has a usable range of operation and it's the reason I didn't like easy access to graphic equalizers when I worked at a stereo store- it was only a matter of time before the customer came in with blown speakers.

I may have mentioned a trip to a high end shop last Fall- the owner was setting up a turntable and they had some music playing at a low SPL. I stood there and listened, then walked up to the speakers and listened for the dispersion and details of the music, then asked "Do a lot of people comment on the amount of detail they can hear when the music is at such a low level?" and he confirmed that it happens frequently.

If I had a dollar for every person who came into the store and when asked "What's the difference?" when I asked "Do you want loud, or good?", I could have retired a while ago.
 
T

Turk

Junior Audioholic
Interesting. Do you by any chance have the speakers set to LFE + Main? If not the LFE should all go to the sub. If all the LFE was going to the sub then you will have to cross the speakers at 250 Hz for movies.

Your best solution when you get the new drivers, is to get two good subs that have good performance to 250 Hz. Put a sub each side of the the 804 D3s and set the cross to 250 Hz. Given what has happened, I would not play loud rock and especially not dub step through them without a high cross. Just because the final coup de grace came in a movie, does not mean other program did not set the drivers up for final failure.
I have s svs ultra 16 sb and the new 4000 series 13.5” sb both next to the front. And I have a dynamo 1000 set really low by the couch. I don’t think I’m short on subs... I would have preferred 2 svs 16 ultra but there was no way it would fit.
 
highfigh

highfigh

Seriously, I have no life.
I could hear both times when the speakers failed. The first time was during a movie where a group of people started banging on large drums before a war scene, the second time was when a spaceship flew overhead and the rumble from the engines took out the speakers. It doesn’t seem to happen at all when I’m listening to music. They work fine for everything from classical, country, rock, metal, pop, edm, and your dub step. They are a very detailed speaker and make every genre of music exciting to listen to. Unfortunately I’m not having any luck with movies which accounts for 90% of what I use them for.
If the diameter of the drums was very large, that's the problem- large drums resonate at a very low frequency and woofers are forced to act as a piston- in car lingo, "There's no replacement for displacement" and the displacement of a 6.5" driver is far too small to allow it to match the air movement of a drum. Also, space ships can't be heard in zero atmosphere but the frequency they use in movies is not for full-range speakers- they send it to subwoofers in theaters and not their full-range speakers, so you shouldn't send it to your speakers, either.

Have you looked at the response in REW when music is playing? The fundamental frequency for low E on a bass guitar is 41.2Hz but what is heard is an octave higher (82.4Hz) unless the player plucks the string at the 12th fret/position or uses a pedal to create the lower octave and if they have a low B string, it's a bit less than 31Hz. There's almost no musical information below 30Hz, unless it's a large drum or pipe organ.

Read the comments in this link- there's nothing in it to suggest that the speakers should be required to produce anything below 30Hz, certainly nothing as a pure tone. BTW- if you go to an outdoor festival or a live show for a rock band- they usually set the PA to roll off in the 40Hz-50Hz range and many bass guitar amps have a HP filter at 35Hz, to prevent damage top their speakers or the PA speakers. While the bass guitar doesn't produce sub-30Hz frequencies with one note, it can do that if two notes are played and the the difference between their frequency is low- this results in a sum and difference tone and if the B AND E are plucked at the 12th position, it's trying to output about 12Hz and no bass rig or PA wants to see that.

https://www.dubstepforum.com/forum/viewtopic.php?f=63&t=290727
 
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