[ricardojoa]

Hi,
as far as midrange frequencies reprodution, is a dedicated midrange always better then a midwoofer assuming with the same brand and similar in desing?

[Vapor Audio]

There's a ton of variables involved obviously, but the easy answer is no - a dedicated midrange is not always better. 

[mitch stl]

"Always" is an incredibly dangerous term.

The human ear is most sensitive in the midrange, from about 100 Hz up to a few thousand Hz. That is also the same frequency range that contains the fundamentals of the human voice and most musical instruments.

If one transitions from one driver to another in this range, one can't help but introduce phase cancellation and reinforcement issues. Even with steep crossovers, drivers overlap each other. Say you crossover a woofer to a mid at 100 Hz, there is still woofer output at 200 Hz - with all of this overlap taking place in the male voice range.

Are there good speakers that crossover from one driver to another in the ear's sensitive range? Yes, but it is a design complication.

There are also a lot of other variables to consider - some designers value volume, dispersion and other factors more. Not everyone has the same set of priorities when it comes to what's audibly important.

[richidoo]

One reason to separate low bass and midrange frequencies is so that heavy bass information does not ruin midrange info if they are playing on the same driver. Soft cone drivers bend under the heavy acceleration at the top and bottom of excursion. But rigid cones may ring at higher freqs. Very few large woofers can pull this off 20-2000 without some problems. Ports are usually employed to be the third driver but they're not perfect either.

Another reason to separate bass and mid is to optimize the power response, so that off-axis frequency response is as uniform as on axis response. All drivers beam as frequency increases, so when a beaming woofer crosses to a dome tweeter that is playing omnidirectional there is a power mismatch in the radiated acoustic energy. On axis they are same SPL, but off axis they are not, so the power response is messed. Off axis sound is what creates most of the echos in your room, which make up a large part of what you hear. Good power response is necessary for a great sounding speaker. A true midrange can connect a bass and tweeter together gracefully, and add a lot of headroom and dynamics.

The additional driver and crossover circuit will add cost and some phase error, but will reduce distortion in other ways that many people prefer. Some people hear the phase shift and would rather avoid that, but they usually give up something in exchange.

[JLM]

There is no perfect speaker.  If you trade-off midrange driver for mid/woofer you'll gain the advantage of specialization but add a crossover which adds it's own distortions. 

Deep bass reproduction in-room adds challenges and it's a fairly accepted fact that the ideal place(s) to locate bass sources is different than higher frequencies.  Using subwoofers can address this phenom plus uses it's optimum cabinet and usually a low level crossover which avoids other distortion issues.

[*Scotty*]

ricardojoa, If I am understanding your question, you are asking if there is any advantage to using a driver labeled specifically as being a midrange rather one that is labeled as a mid-woofer that will do dual duty covering the midrange.
 In my experience this is frequently more of a marketing distinction rather than a case of a clear advantage of the driver labeled as a midrange only over one labeled as a mid-woofer.
You will have to look very carefully at the two drivers specifications.
The specs to pay particular attention to and compare are:
Xmax
Mms
Fs
Power Rating
 Sometimes it makes sense to use a mid-woofer when you are building a three-way loudspeaker and you are crossing over into the woofer below 300Hz. In this case the mid-woofer may see a considerable amount of bass energy depending on the crossover slope. If you are crossing over at 300Hz or higher you may be able to use a midrange only driver that may have a reduced Xmax or lower power rating.
It would be nice if such a driver had a lower moving mass, better sensitivity or a smoother rolloff at the top of its passband where you are crossing over. These would be clear reasons to look at the using the driver over its mid-woofer counterpart.
 If you are building a two-way loudspeaker then you are well advised to use the driver with the higher Xmax and lower Fs.
 Looking at the Madisound website, they have fewer mid-woofer drivers listed in the midrange category than they they woofers.
They have sensibly not broken down the woofer category into drivers labeled midrange and mid-woofer.
I wouldn't be overly concerned with what the driver is labeled as the specifications are much more important when it come to deciding on the suitability of a given driver for your application.
Scotty

[JohnR]

An 'equivalent' midrange driver will typically have higher sensitivity and require a smaller enclosure.

Example to compare:

http://www.madisoundspeakerstore.com/approx-5-midrange/scanspeak-15m/4624g-discovery-5.25-midrange/
http://www.madisoundspeakerstore.com/approx-5-woofers/scanspeak-discovery-15w/4434g-00-5.25-midwoofer-4-ohm/

[ricardojoa]

Thanks for the responses. I guess there are just too many variables.
But when just refering to drivers alone, variables from xover design no longer are involved. Then it becomes why one chooses one over the other. I think construction, material, weight of cone etc,(not sure what else) becomes more important.

[Ric Schultz]

Here is my idea of a great speaker:  Powered equalized bass.  This way the mids and highs are run off their own amp and there is no modulation from the woofer frequencies on the mids and also no back emf from all the pumping the woofs have to do.  Then you put the midrange in a separate smaller enclosure so it won't naturally go down very far or put it on an open baffle so again it won't play very low.  Then use a line level xover to limit the lows to the mids/highs.  A single .005 Teflon cap before the high frequency amp will usually do.  The value is determined by the frequency cutoff you want and the input impedance of the amp.  Alternatively, you can change the coupling caps in your amp (if they have coupling caps) to a lower value and higher quality cap.  This way you improve the amps sound as well as roll off the lows to the mids.  You then isolate the upper frequency box/panel from the woofer box by islolating material....or have it on a stand next to the powered woofer.  The Behringer Inuke 3000DSP is an inexpensive high powered stereo amp that has a built in crossover and equalization.  Perfect for running woofs.  Equalizing the bass is amazing and bi-amping allows you to use a lower powered/better sounding amp on the top.

If you are not going to bi-amp then there are all the tradeoffs mentioned above.  Bi-amping solves all the problems and allows way better bass (especially with equalization) and midrange.  It will beat a two way speaker (assuming both are done to the same level).

[jerryleefish]

 I have bi amped into a similar configuration to solve two problems. Using a single Luxman 3045 into a 3 way folded horn I had  an imbalance between wolfer
and the mid range/tweeter. Also, the the mid range was being sucked out.
Switching to two amps I was able to lessen the wolfer output by turning down its
attenuater by a third. The 3 way crossover required the wolfer coil to be separated
from the rest of the network. These two sections were then driven by their respective amps.
There is also an advantage of being able to match amp op impedances for each section if the wolfer and mid range/tweeter impedances are different.