Hello! I recently acquired B&W 703s'. I have not been able to get a satisfying answer to this question from B&W: "what is the meaning of -6dB at 30Hz". This is listed as the frequency range. The frequency response is listed as 38Hz - 25Hz +/- 3db on ref. axis. QUESTION: <!--color--> Thanks.
It means that at 30hz the speaker will fall from linear by 6db. For example, when measuring the speaker's frequency response it will remain relatively flat until it is required to produce 30hz and then it will be down by 6db in relation to the baseline.
A practical way to look at it is that -6db at 30hz is still usable bass response where -10db is considered a cut-off point. A +3db at 5Khz would indicate the speaker has an excess of energy at that frequency. Ideally, you would want a speaker to remain flat from below 20hz to above 20khz.
where can i find stereophile test CD? any website that i can have more info?
Hello! I recently acquired B&W 703s'. ....
just a question. did you do a comparison between 603 and 703?
when i tested B&W, the salesman asked me to audit only 803 and 603.
When I asked about 703, the salesman said that he would recommend to add better cabling/amp with 603 instead of buying 703.
Scroll down to the bottom of the page. Well worth the price for the test signals and some great music thrown in for FREE.
What i actually did was to compare it (703) against the Vienna acoustics Beethoven Baby Grands', i had not considered the 600, as i was favouring the Baby Grands. I had considered the 803s' but that would have given me only 3hz on the low end and for my dollar it was not enough return.
Thanks for your response. It is quite apparent that i am missing a critical point. My dilemma is that i don't under how a speaker who'se bandwith starts at 38Hz, can be written up as having any ratings (in the cast the 30Hz) that are less than the lowest frequency according to the specs. that the speaker is capable of producing. Thanks.
Hi! Thanks for the tip!
Harry, B&W are actually being quite fair and useful in stating the measurements as they did.
The speaker measurement is first given in what is widely accepted as the industry standard of +-3db across the stated frequency band. They are saying that the speaker is accurate within + or - 3 decibels from 38hz to 20khz under ideal conditions for measuring.
What B&W is also telling you is that the speaker can reproduce a 30hz frequency, just not as accurately as it can the frequencies above 38hz. This is useful in that most all speakers have a more difficult time producing the lower 2 octaves and at some point simply cut-off.
It really is a matter of them saying that the speaker is great above 38hz and even pretty good down to 30hz. If you were to play a series of test tones starting with 60hz and ending at 20hz, you would notice the test tone at 30hz was not as loud as the test tone at 40hz...and the test tone at 20hz would likely not be heard at all. However, even a 30hz sound wave that is down 6db from linear is still a fair amount of low end extension and will certainly add to the music's dynamics.