SS or Seas Excel as a midrange

[esl]

Hello!

I just started a driver selection process for my new 3, or maybe
4 way speaker project. After some thinking it turned out that
there are actually two drivers on my shortlist:
Scan Speak 12M4631G00 and...
Seas Excel M15CH001.

Well, I see that SS can actually go a little bit higher, but
my intuition tells me to pic Seas Excel.

Is anyone familiar with the sond of these drivers?
Which one would be more transparent and dynamic?

To your information, it's going to work with Audax HD-3P
as a tweeter and 8" driver as a midwoofer.

Greetz,

Aleph

[PaulHilgeman]

I would say either would be outstanding, but if I were you I would go with the SS midrange. I am not too sure how I feel about a $225.00 USD poly cone midrange. For the 8"ers I would go with the Seas Excel. I have only heard the W18, but I felt that its best characteristic was the 100-300Hz content.

Also, keep all of your XO's out of that delicate 300-3000 Reigon if you can. Especially the 300Hz reigon.

-Paul Hilgeman

[5th element]

Paul got the price wrong as far as I can tell, the M15 doesnt cost $225 it costs $150, its the SS that is $225, acording to madisound.

Its the thing that faces us all unfortunatly. Which drivers should I choose, just be glad we have such a good range to choose from!

Anyway I would say that both, as Paul said, would be amazing and its one of those unfortunate situations in which we cannot listen to them and then decide. But for me if the SEAS was a mag cone I would go for that over the SS, im listening to my w15cy's as I type with Whitney Houston and she sounds superb, one of the mag cones party tricks fmale voices. Oh and on that note dont count out the w15. It may not be classed as a mid driver but it sure as hell kicks out one helluva performance in the midrange. I really would like to compare the m15 directly with the w15 as I think that would be an intersting show-down. I would imagine tho that they both would probably be as good as each other as are all these expensive drivers, but with differences. They are all pretty much of a muchness, in that they are all very good but its down to personal taste. I would say that the SS and SEAS poly would sound more similar then the SS and the mag, so its really down to price.

One other thing to consider is the size of the cone, I know this is going to be a mid application and high excursion isnt really going to be called for, but still the lower it is the less nasties you get. The Seas cone is bigger then the SS so therefore will move less at a given frequency. If you do as Paul suggests, which I recommend too, and keep the xover out of the 300hz range then you would really be thinking of about a 100-150hz xover. Then you should really think about an active xover, but leaving that aside. If you were to crossover at 150hz then at high levels the unit would still need to move quite a bit of air. Then we hit on the reverse of this the actual excursion of the drivers. Both the SEAS and SS have the same max before DMG excursion, which is Gr8. But the SEAS only has 1mm xmax, I can tell you this isnt enough, id want to remain linear, which I assume you do too. My w15's in a sealed cabinet crossed over electrical 150hz, 12db which sums to 24db acoutic, move WAY more then 1mm. The scan on the other hand has 3mm xmax, which thinking about it now would probably make me choose it over the SEAS.

However the w15 may work out better anyway, it is easy to work with (appart from the peak of the cone, which isnt as hard to sort out as everybody claims it is), you can cross it over at 150hz keeping everything linear, is can be xovered at 3500hz with no problems to keep out of the 3000hz, the Audax tweet needs a high xover point from memory anyway. It also is very transparent and very dynamic and the best bit is that is costs less then all the rest, you can almost buy two w15s for the price of 1 SS.

Then if you do realise you have made a blunder in you choice of driver you have spent the least first off, but the w15 can make a fantastic small speaker for a bedroom. If you bought the either of the mids and didnt like them then your stuck unless you want to make another three way, the w15 lets you make a two way bookshelf.

This may seem a little bit of a cruel comment to make but what is your hifi like, ie your source and amp. If done right the speakers which you will end up having would cost nothing short of silly money as far as consumer goods are concerned. Dont forget that altho we can make speakers that would cost $5000 at a fraction of that, they still need $5000 amplification.

[5th element]

Also if you are going to go three way and use and 8" as a bass speaker then it all depends on the xover freq you choose. If I play just the bass of my three way which is at 150hz 24db, youd be surprised at how little comes thru them, nothing but the bass, which is what you'd expect really but nothing too critical to detail and transparency, this is assuming you dont get any boomy coloration. Anyway if you have a higher xover point then a better MID/bass is needed, because it will be called on to do more mids.

I have the peerless 850147's doing the bass on mine, I moved the xover from 330 to 150 and the biggest difference was more detail, as the excel is better at that then the large 10" peerless poly. If you cross low look to a driver which will be the best for pumping out the seismic tremors. Something like the peerless HDS
850490, this is the 8" version of the 850467 6.5" which I have. The 850467 kicks out bass with applomb so I would imagine the 850490 would just do the same but better. Peerless drivers from what I have read and what I have heard, if they are good at one thing it is deffinatlely BASS.

If the budget stretches why not consider using the XLS 10" and its passive radiator as the bass section crossed over at about 150hz. This would remain physically small as the box needed is only about 1 cubic foot.

Hope all this is of any use Matt

[PaulHilgeman]

I stand corrected on the price... Sorry

Have you considered somthing with dipole bass? This would probably require you to get down to about 100Hz, since you usually need to use large drivers with high x-max for dipole bass.

***ramble***

If I could design the ultimate system, which it sounds like you are trying to do. I would go with one of the very nice tweeters out there, probably a Hiq OW1. For the mids, the SS 12M, then a midbass, I would go with Seas W22, and for the bass, I would go with two 12" Peerless XLS woofers in an H-Frame Dipole. For below 40Hz, I would go with a Stryke AV15 in a sealed box. I guess this would be 5-way. It would be sweet though.

[Ken L]

Originally posted by esl
and 8" driver as a midwoofer.

I suggest you select the driver with regard to which will match best and have a seamless crossover to the 8" mid

If you haven't selected the 8" mid, I suggest that you pick the drivers on how they will match with each other and have a seamless crossover

regards

Ken L

[esl]

Hello,
In the first place, thanks for reply.
Yes, 1mm of Xmax for Seas m15 could be not enough,
until I go 4way, with mibass between m15 and woofer.

I seriously consider building a 4 way speaker.
My entire budget is about 1500 $ for drivers, but please bear
in mind the fact that here in Poland some drivers are hard to
getand more expensive. Anyway, I am going to buy from
somewhere in US.

So, here it goes... I plan to use HD-3P as a tweeter, because
of two things: I like it's "electrostatic" sound, and I can buy
a pair here in Poland for 300 $ which is a bargain for this
driver.

This is why I need a midrange that could go as high as
approximately 4.5 KHz. And this is why I mentioned Seas m15
and SS 12M.

Could any of the magnesium-cone Excel woofer be crossed so
high (4.5 KHz) ? I was thinking about W12CY001, but it would
need a really high crossover slope to match HD-3P.
M15 is much easier to match in this circumstances, and yes,
it would be an interesting show-down.

Anyway, what if I'd go for 4 way, in such a way:
HD-3P as a tweeter, factory Xover freq. (4.8 KHz)
M15 from 4.5 KHz down to 500 Hz
Good 8" midwoofer from about 450 Hz down to about 80-120 Hz
downward firing 10"- 12" subwoofer crossed about 80 Hz

What do you think about such a configuration?

Could you suggest midwoofer and subwoofer for me?
I can buy Peerless XLS-12 quite cheap here, but I don't like
passive radiators and I wonder whether would efficiency of
XLS-12 be sufficient enough to match the rest.

Cheers,

esl

[PaulHilgeman]

Well,

First of all, you probably don’t want to crossover that high, I would go with a max of 3500, but better at 3200 or 3000. The problem is that the closest you can get the center-to-center spacing is limited by the size of the drivers, so you are going to get a very narrow on-axis lobe. I would go with the Scan-Speak and cross it at 3000Hz, to the tweeter. You will want to put them as close as possible together. I also feel that the sound of the paper midrange is going to match that of the tweeter as much better, the poly sound will not.

With the scan midrange, you are going to want to HP it at probably about 200Hz. I would personally go with one of the new scan-speak woofers, probably the 8”. I would probably use two of them.

[esl]

Hello,
first things first - I am going to use Audax HD-3P, so I HAVE TO
cross midrange at 4500 Hz or even higher. That's why there
are small-coned midranges on question.

In the second place, I don't want 8" bass, I want 10" or maybe
larger.

What about this one as a specialized down-firing subwoofer?
http://www.madisound.com/seas/H1209.pdf

I would cross that down-firing subwoofer at about 100 Hz, so it
looks like I would need another driver to cover the 100-400 Hz
range, as I stated before.

I know that HD3P and Excel M15 are both approx. 90-91 dB/2.83V
so, it would be nice to find an 8" woofer with appriopoate
efficiency.
(This 10" Seas woofer is 87 dB, but placed close to floor should
have a 3 dB efficincy boost, correct me if I am wrong)

a.

[PaulHilgeman]

Have you designed a speaker before?

If not... I wouldnt do what you are about to do.

If So... Remember BSC, you will probably want two 8" woofer to cover 100-400Hz, Also, I would not XO in the 400Hz range, it will majorly mess with many acoustic sounds as well as male vocals. Shoot for 250 or so. What XO topologies are you going to use? What slopes, Active, passive etc. How do you plan on counteracting the effects of crossing at such a high frequency to your tweeter, and have you investigated the lobing characterisitics of this?

-Paul Hilgeman