[heliumflight]

Hi Folks,

Could any of the audio gurus suggest as to why I'm not getting authority in the bass when the the B&w archieve shows that the frequency response goes to below 30hz (30Hz ? 25kHz. Better than ? 2dB)? Also the minute I put music that has the sound of the drums then it is a big heart burn as the sound of the drums is febble ..... But in music without the drums the midrange is to die for'

Do you think my speakers are past their age as I can with 100% conviction state the drivers are perfect.

http://www.bowers-wilkins.fr/display.aspx?infid=773&pid=1876

Kindly enlighten

Kindest regards
Amp: Bryston B 60-R
Speakers: B&W DM4
Source: LG DVD + Beresford  MK IV
I.C: Shark  / Monster Thx
Cables: 4mm Jamo OFC 
Music: Grateful dead, Eagles, Jethro Tull, Steely Dan, Allman brothers

[srb]

There seems to be a discrepancy between the DM4 Archive document ( 30Hz - 25KHz + or - 2dB ) and the DM4 Manual ( 80Hz - 20KHz + or - 5dB ).
 
I think the 30Hz -2dB spec is overly optimistic for a 6-1/2" driver in a medium size bookshelf cabinet.
 
However, if the 80Hz -5dB  spec is correct, that may be exactly what you are hearing, "feeble" bass.
 
If that's not the case, perhaps the capacitors in the crossover are shot.  Kind of tough to speculate.  I don't know if you will find anyone on the forum who actually owns or has owned the speaker, but it would be interesting to hear their opinion.
 
Steve
 
* Not an audio guru

[heliumflight]

Thankyou Steve for the insight. Are speakers also biased on the type of music you play.

[srb]

Well certainly you hear people talk about this speaker is good for rock and that speaker is good for jazz, etc. but I find a well designed speaker sounds pretty good on all types of music within its physical limitations.
 
Obviously full scale orchestral music with many instruments, tympani, etc. cannot be realistically reproduced by a small bookshelf speaker.
 
The same goes for pipe organ or some electronic music that has electronic bass with frequencies below the 40Hz fundamental of a standard bass guitar's lowest note or electronic bass drum with frequencies below that of a standard acoustic bass drum.
 
That being said, I have had bookshelf speakers with even smaller 5" woofers, where although the bass was limited, the drums by no means sounded "feeble" as you describe.
 
When you say that the drivers are "perfect", I assume you mean looking at the fronts, that the surround is intact and there are no holes in the cone.  However perhaps the material of the spider has significantly dried up and hardened, preventing proper cone excursion that it had when new.
 
Specifications aside, it does seem that something is physically or electronically wrong with the speakers.  Have you tried any other similary sized speakers in the system and in the same placement as the B&Ws?

[heliumflight]

Steve, Yes physcially they are perfect! The driver seems to be made of plastic kind of material which is quite stiff. I have not tried any speakers as yet. But last week I have given an order for Iron stands (20 kgs each ) as I was told that my 4 kgs stools were the culprit for feeble bass and  impact of the drum sound. Do you think this was the weak link?.... Will keep you updated on the improvement in S.Q

Kindest regards

[srb]

High mass stands can certainly provide an improvement in bass, although I would expect the improvement to be more incremental than night and day.
 
But theory and speculation are just that, and often the proof is in the pudding, as they say.  The only real way to know is to actually try it.
 
A nice pair of stands can be used with any speaker, so I suspect it is a good investment whatever the actual outcome with these speakers.  I look forward to your post after you've had a chance to audition with them.
 
Steve

[lonewolfny42]

heliumflight....

Let's see....vintage B&W DM4 monitor speakers...circa 1972.

They look like this.....



What I have read.....

The DM4 uses the same tweeter (Celestion HF1300 MkII) and supertweeter (Coles 4001) as the famous Spendor BC1.

The DM4's offer good musicality in an "old style" B&W design...but they need a bit of wall support not to become to lean in the bass.

So....try a better placement...see if that helps.

Do you think my speakers are past their age as I can with 100% conviction state the drivers are perfect.

They may have seen better days.....looking at your other equipment...that does not seem to be a problem.

[srb]

Chris,
 
Nice research and good suggestion.  So it appears that back in the early 70's B&W had not yet started to manufacture their own drivers?
 
Steve

[lonewolfny42]

Chris,
 
Nice research and good suggestion.  So it appears that back in the early 70's B&W had not yet started to manufacture their own drivers?
 
Steve

Yes....that's what I gathered....
Might be a problem with his crossovers...their vintage speakers....I'd have them checked out.

[srb]

Might be a problem with his crossovers...their vintage speakers....I'd have them checked out.

Well that's what I first suspected - crossovers and/or driver suspension.

But as we all know, speaker placement certainly affects bass output, and that should have been one of the first things to suggest.  Doh!

Steve

[lonewolfny42]

Their value now is in the $125.00 to $150.00 range....used.

[heliumflight]

Yes I did try pushing them against the wall, the bass increased but the vocal got smeared and drowned and become quite irritating.

Will keep you posted after I get my stands made to order....Do you think these vinatage speakers match in performance/ quality to new speakers?

heliumflight....



The DM4's offer good musicality in an "old style" B&W design...but they need a bit of wall support not to become to lean in the bass.

So....try a better placement...see if that helps.

[S Clark]

....Do you think these vinatage speakers match in performance/ quality to new speakers?



No.  But that doesn't mean that you can't enjoy them. 

[heliumflight]

There seems to be a discrepancy between the DM4 Archive document ( 30Hz - 25KHz + or - 2dB ) and the DM4 Manual ( 80Hz - 20KHz + or - 5dB ).
 
I think the 30Hz -2dB spec is overly optimistic for a 6-1/2" driver in a medium size bookshelf cabinet.
 
There is another correction the driver size is 8".

[srb]

There is another correction the driver size is 8".

My mistake.  The spec sheet said 164mm, but now I see that is "effective cone diameter", which sounds about right for an 8" driver.

All the more reason to expect decent bass if everything was mechanically and electrically working correctly in the speaker.

Steve

[Point]

I realize this is a relatively ancient thread, but I was googling my ol' DM4's and came across it, so I thought I might pipe in since I may be one of very few people that own a pair of these with all the original parts.

Mine push plenty of bass, so yours should too. Mine just sit on a desk, a few inches from a wall. I'm personally in love with them, and intend to keep running them on my home stereo for as long as I can listen to music. They sound gorgeous, warm, rich. Bassier than most other bookshelf speakers/monitors that I've had. I also have Event 20/20's and a couple NS-10M's, and neither are really ideal for just enjoying music through. The NS-10's are certainly feeble in the bass department, and the Events are too clear, precise, almost clinical in their sterile perfection.