Speaker phase observation and question?

Tim & Erik, thanks for the excellent info and the informative link, which I’m still going through.

Kalali, first, although the term "impedance" is commonly used to simply refer to a number of ohms, to be precise a speaker’s impedance is a vector quantity, meaning that it is comprised of both a magnitude (the quantity that is measured in ohms) and a phase angle (measured in degrees). If the impedance is purely resistive at a given frequency the phase angle will be 0 degrees at that frequency; if it is purely inductive (hypothetically speaking; no speaker will have an impedance that is even close to being purely inductive at any audible frequency, or it would not be able to consume any power at that frequency) the phase angle will be +90 degrees; if it is purely capacitive (again, hypothetically speaking) the phase angle will be -90 degrees.

Also, as has been mentioned above, the phase angle of the impedance describes the amount by which voltage leads current (in the case of a positive/inductive phase angle) or voltage lags current (in the case of a negative/capacitive phase angle), at a particular frequency.

But to address your question, I suggest that you take a look at this thread. The entire thread is well worth reading, but note especially the latter part of Atmasphere’s post dated 1-9-2017 (beginning with "I feel like several points need clarification ..."). The short answer is that sound quality **does not** benefit from low impedance design, but other factors such as cost and marketability may. With those factors deriving in part from the fact that solid state amps can supply more power into low impedances (up to a point, of course) than into high impedances. The background and previous experience of the particular designer, and the kinds of designs he or she is most familiar with, also seem likely to be factors in many cases.

Best regards,
-- Al

Hi Almarg,

I am definitely on team "easy to drive speakers." Get easy to drive speakers and a lot of amps will sound really great.

Get demanding speakers, and your amp costs may go up considerably.

So make sure if your speaker is demanding that it's really worth the cost of ownership. Being able to tell amps apart is not why I buy speakers anymore. :)

Best,

E

Likewise, Erik. Putting it another way, I prefer the dollars I choose to invest in an amplifier to go as much as possible toward sound quality and build quality, rather than a lot of that investment simply going toward watts and amperes.

Best regards,
-- Al  

Hi Kalali,    well to answer your question... quality would not benefit from a design with a combination of low impedance and low phase angle,  but when you are designing, if you want a very detailed speaker, you may choose a very stiff cone,  you may want a low qts for a lean sound or a higher qts for a sealed box design, You may want a driver that can cover 4 or 5 octaves or a driver that has no peaks or one that only has a very smooth rolloff on the top end or one with a low fs.  What it all comes down to,  is that when you have a design in mind,  you tend to find a driver that comes as close to  what you are after in sound quality and deal with phase angles the best that we can. 

Thanks for the excellent and thorough explanations. I had completely missed the interrelationship between the impedance and phase angle and voltage/current interplay referenced in the posts. It all makes sense now.