What happened to the high-efficiency midrange drivers?

[spasticteapot]

I've been looking at various midrange drivers and have notice that most of them are extremely inefficient - most are 84dB-87dB at 1W. Considering that most 3" and 4" midrange drivers have tiny voice coils unable to deal with more than 30W or so, this seems like a recipe for low dynamic range. Many of these drivers also seem to have a fairly low Fs, and appear to be designed so that they might be usable in a small 2-way as well.

Is this low efficiency a result of using stronger, heavier cones to reduce distortion? Or is it just a case of design compromise that's killing efficiency?

[ajinfla]

https://www.madisound.com/store/prod...oducts_id=8928

The MMD 4" mid I just received from Harman is about 92db/2.83v sensitive.

Are you looking in the right places?

[mzisserson]

It seems the midange is becoming a lost art, being replaced by full-range drivers. However the high eff is needed for impedance control.

There are a couple out there, you just have to look. Scan makes a couple, that audax, focal, and Seas to name a few.

[ajinfla]

However the high eff is needed for impedance control.

[mzisserson]

Maybe not in your perfect world. But in my world where I deal with Sony receivers and low power amps, I rather pad the mids for easier loads through the lower band-pass sections. Controlled impedance through the mid is also a key factor in smooth, audible response from what I have found.

I am not looking for an argument. Just sharing what has worked for me in real rooms, under real conditions, with regular people who just want good music.

[Mayhem13]

If you're not tied to small diameter drivers, the B&C 6MD38 is an excellent, true 95db eff midrange driver that i've worked with.

[johnnyrichards]

https://www.madisound.com/store/prod...oducts_id=8928

The MMD 4" mid I just received from Harman is about 92db/2.83v sensitive.

Are you looking in the right places?

Nice choice, AJ. I have a pair of MMD 6.5" woofers due up for a project. Harmon, through their Infinity brand, has created some enviable drivers.

[MagicO309d]

What about going WMTM to compensate for midrange efficiency issues with many of the highly regarded full-range drivers available?

Is there a sound quality hit with going the MTM route for the midrange over a single midrange driver, assuming cost is no issue?

[ajinfla]

Controlled impedance through the mid is also a key factor in smooth, audible response from what I have found.

Via heat, thrown away sensitivity and dynamic capability? I see.

But in my world where I deal with Sony receivers and low power amps, I rather pad the mids for easier loads through the lower band-pass sections.

I've heard of audiophiles desiring things like midrange "warmth" before, I just never knew that's how they got it.

[dantheman]

How do you guys get these Harman mids? On paper they look a lot like winners!

Dan

[ajinfla]

How do you guys get these Harman mids?

Do you own a ski mask and a gun?

Actually, Harman makes lots of replacements parts (hint, hint)

[ligs]

And a hefty price tag to match.

[dantheman]

Thanks AJ. I'll have a look around. The measurements on those are impressive. I might like to get some just for fun.

OK, the price doesn't look bad at all to me. Nice! Thanks again,

Dan

[johnnyrichards]

Dan, you can get a lot of them new on Harmon's website, the 4-6" models generally run less than $40-60, the stamped frames run a little less than the cast frames.

I have been scouring ebay for quite some time to score the several I have.

[dantheman]

You da man Johnny! Do you have anything built with them?

Thanks,

Dan

[2leftthumbs]

Seas H453 here for $15 http://home.comcast.net/~jhidley/. sens 89.67 dB.

[gowa]

Do you guys mean Harman?

[airtime]

I've always had good luck with Seas midranges. Paper cones, sound great and still affordable. Currently I'm using a seas H1262 with good results.

I agree - midranges are becoming a lost art! Being replaced by powered subwoofers and the like

[Jeff B.]

I've been looking at various midrange drivers and have notice that most of them are extremely inefficient - most are 84dB-87dB at 1W. Considering that most 3" and 4" midrange drivers have tiny voice coils unable to deal with more than 30W or so, this seems like a recipe for low dynamic range. Many of these drivers also seem to have a fairly low Fs, and appear to be designed so that they might be usable in a small 2-way as well.

Is this low efficiency a result of using stronger, heavier cones to reduce distortion? Or is it just a case of design compromise that's killing efficiency?

Maybe you're just looking at small full-range and wide-range drivers and calling them midranges due to their size. These drivers, in order to cover a wide bandwidth will have a lower Fs, which when coupled with the small Vas of the small cone, results in a fairly low sensitivity. A true midrange driver, on the other hand, will have higher Fs, which will enable the driver to have a much higher sensitivity in comparison. Look at that relationship and you will see what I mean. Most true midrange drivers can have a fairly high sensitivity rating.

Jeff B.

[Face]

http://www.eighteensound.com/index.a...roduct&pid=243

https://www.madisound.com/store/prod...oducts_id=8926