Midrange driver w/ good transient response?

[Elbert]

Fellow audiots, I need some advise here..

I'm planning an active 3-way system using some old but good SEAS 13" 33 F-WB woofershttp://www.seas.no/images/stories/vi...-wb_and_dd.pdf

I intend to cross these over fairly low, leaving a midrange unit to cover the entire critical 200-2kHz range.

As for tweeters, I'm probably gonna go for the SEAS DXT units, as I find the dispersion control feature of these both novel and interesting.http://www.seas.no/index.php?option=...184&Itemid=179

So, that leaves the midranges.... I realise there are no one perfect midrange, instead I'm hoping to find the optimal midrange for my intended application and design priority .

The use, I've more or less described.

Rather than obtaining perfect linear response and minimized distortion levels, I'm aiming for a design that can reproduce dynamic music with engaging transient response and detail at convincingly "realistic" sound pressure levels. loud and clear.

I've rummaged through previous posts and the web in general in search of greater midrange wisdom, but what i find is that most information is concerned with frequency response and harmonic distortion. Sure, a lot of interesting info here (in particular on zaphaudio.com), but I have failed to find much on how to identify midranges/ midwoofers likely to have good transient response.

Any suggestions to what criteria/ parameters to look for here, or in deed, any particular driver recommendations?

For their good quality (and some patriotic sentimentality) I do have a soft spot for seas drivers.

I have looked at a 5" SEAS midrange, the MCA15RCY
http://www.seas.no/index.php?option=...102&Itemid=124
which seems to be designed specifically to cover the frequency range I'm intending to use. Also, I reason that 5" is a good size in terms of of axis response.

The SEAS ER18RNX http://www.seas.no/index.php?option=...111&Itemid=133 has also been recommended to me as a good new design, made even more interesting by Zaph's comments and SR 71 application.

but then again, could some of the metal cone designs have any merit for my application?

Could 2 midranges per speaker have any advantages?

The Tangband W4-1337SA certainly looks sexy, at least on paper (except for the somewhat low efficiency and power handling)

Anyway, enough ranting, I will now humbly await guidance and enlightment from those knowing more than I do!

[EspenE]

I cannot see how you can define "transient response" in one specific frequency range, as transients have components from all frequency ranges.

However, as to impulse response, power compression and ability to reproduce realistic dynamics there IMO really is no alternative to relatively large (8-10") prosound drivers.

Look at the JBL 2118 or 2123, or the 18sound and B&C midrange drivers.

[sreten]

Hi,

not cheap, but checkout :

http://www.troelsgravesen.dk/JA8008.htm

/sreten.

[Elbert]

Hi Espen,

Well, transient response, impulse response.. could well be I('m mixing up terms here, been a while since I messed around with audio projects!. But what I'm talking about is a snare drum that goes "SMACK!" in stead of "slapp" if you know what I mean...

Had a look at some of those drivers you recommended... Efficiency and power handling is awesome, which is rather common for PA speakers... but how do they really sound....?

Most PA type speakers i have listened to are just loud but more often than not more or less tiering and unpleasant to listen to... (unless you actually happen to be at a concert in a good venue where the sound technicians knows his stuff)

Sreten,

Those Gravesen speakers really look interresting! There certainly is an appeal to simple high efficiency systems like that. The almost minimalistic approach, perhaps with an element of "alchemy" thrown in.
Couldn't find any prices on the web page, but from the looks of it, probably rather expensive...

Well, this time around I'ts going to be an active 3-way, one day when i get a nice hose with a proper listening room I can start playing around with horns and high efficiency stuff again!

[sreten]

Originally posted by Elbert


Sreten,

Those Gravesen speakers really look interresting!
There certainly is an appeal to simple high efficiency systems like that.

Hi, you might be missing the point ...... , /sreten.

Compared to all other speakers I've made, the area where this
speaker differs the most is in its ability to reveal musical transients.
The speed and attack it can produce is something none of all the
other speakers on this website can manage. It's fast, very fast.

you do have a 96dB/W low bass unit .......

[Elbert]

Sreten ,

I did get the transient bit, and that sounds familiar to what I experience with my voight-horned Corals for all their other flaws..

The more I read around the more I get the impression that there is some connection between high efficiency and good transient response... hmmmm...

[crazyhub]

Originally posted by Elbert
Sreten ,

The more I read around the more I get the impression that there is some connection between high efficiency and good transient response... hmmmm...

the more I listen to low or high efficient GOOD speakers, the more I get the impression that there is some connection between good speakers and good transient response. Some 83-84db monitor are amazing in this "transient" matter.

[Elbert]

Aaaah! The French, always so philosophical and convoluted!

But who am I to argue, it was after all some good Frenchmen that really taught my about the pleasures of GOOD wine and food! They must be on to some thing...

So what is a good midrange then... must say I'm leaning towards the SEAS MCA15RCY, seems like Mr Gravesen were reasonably positive about these, and he seems to know his stuff..http://www.troelsgravesen.dk/PMS.htm

[EspenE]

Originally posted by Elbert

Well, transient response, impulse response.. could well be I('m mixing up terms here, been a while since I messed around with audio projects!. But what I'm talking about is a snare drum that goes "SMACK!" in stead of "slapp" if you know what I mean...

Had a look at some of those drivers you recommended... Efficiency and power handling is awesome, which is rather common for PA speakers... but how do they really sound....?

Given the right crossover, good prosound drivers sound great. I have (and still use) nice systems with Seas W22, Seas 27TDFC, Seas Millenium, Peerless XLS, Scan-Speak 2900 etc. None of those systems can compare with systems based on prosound drivers when it comes to realistic dynamics, headroom and general ease of reproduction.

The snaredrum SMACK! you speak about has somthing to to with just that.

[crazyhub]

Elbert,
I don't want to go to the "best suited mid-driver" opinion, I would just advise you to decide what is your necessity.
At the moment you want to cross the mid relatively low (200Hz) you need "drive" in the low-mid range particularly if you cross your woofer with steep slopes. "Drive" at 200Hz...hum...you need some consequent SD so a 16 to 20cm should be more adapted than a 5". That's the first point and certainly the most important one. A 5" could be suffisant in this "drive" matter if you were going to use a large baffle as in the Troels PMS.
Than...transients (or in reality what you perceive as..): they do come VERY mainly from the global design of the speaker, NOT from one or more tech features of its drivers, at least not from those related to the T/S parameters except if drivers are working at Fs which isn't the case with a mid-driver. So looking at the distorsions curves isn't a bad thing. If you need high spl, than yes, PA drivers certainly should be well adapted. If you remain in the domestic hifi field, between the two SEAS you named, I would personnaly chose the ER18RNX, better low-mid drive, handles (directivity and distorsions issues) a 2Khz fr cut. Also, because of the type of woofer (no stiff cone) you still have, I would not look at the stiff coned mid-drivers.
But...I would personally chose the vifa XG18 as it seems to be particularly adapted to a 200-2000hz range, check Zaph's site if efficiency is enough for your design (or two of them).
My two cents. (
BTW, as a french but alsacian guy, I would advise a good "choucroute" + Rieling