Large Woofers!

[Tenson]

Hiya!

I have short listed three large woofers that will all be suitable for the design I have in mind but I have not actually heard any of them. So, I am stuck as to which one I should be using.

The design puts them in an open baffle doing mainly upper bass and midrange up to a XO @ 1.5KHz.

I would greatly appreciate your subjective opinions on which of these you like most.

1. Eminence Magnum 12HO
2. Precision Devices 12SB30
3. P-Audio SD-12

The P-Audio looks the biz and the Eminence seems to have the smoothest response, but that could just be the smoothing and the Precision Devices wins very so slightly on SPL.

What to choose!? I like detail, finesse and accuracy. Obviously all of them can give it some welly!

[ScottG]

There is really only one choice here if you are not eq'ing to some extent.

see this thread:

The strangest thing

[Tenson]

I am EQ'ing. The spec for what will work in this design is very strict, I have looked through nearly every speaker manufacturers catalogue and compared them. These three are the only ones that cut it. What I have been mainly looking for is a smooth response up to about 3KHz and the highest max SPL in the low frequency, as I will be EQ'ing. B&C and JBL are not bad so I might be able to use these but the three I have listed are better in the areas I have mentioned.

All three should be quite good I believe as they should be 'supremely clean' as T put it, at normal listening levels, but which is 'de best' for midrange sound quality??

Having said that I just tried putting the Supervox into T's open baffle spreadsheet and it tops all of those drivers for max SPL across the board. Now it obviously has a very high sensitivity so that may be why... I'll see what Thorsten thinks. It is a very different woofer to the sort we have been looking at and as he is a fan of Supervox so I’m sure he would have suggested it. How would you describe their sound by the way? Good for all sorts of music like anything from classical to heavy metal and emo? Or better for ooh so warm vocals and acoustic stuff?

[ScottG]

Originally posted by Tenson
I am EQ'ing. The spec for what will work in this design is very strict, I have looked through nearly every speaker manufacturers catalogue and compared them. These three are the only ones that cut it. What I have been mainly looking for is a smooth response up to about 3KHz and the highest max SPL in the low frequency, as I will be EQ'ing. B&C and JBL are not bad so I might be able to use these but the three I have listed are better in the areas I have mentioned.

All three should be quite good I believe as they should be 'supremely clean' as T put it, at normal listening levels, but which is 'de best' for midrange sound quality??

Having said that I just tried putting the Supervox into T's open baffle spreadsheet and it tops all of those drivers for max SPL across the board. Now it obviously has a very high sensitivity so that may be why... I'll see what Thorsten thinks. It is a very different woofer to the sort we have been looking at and as he is a fan of Supervox so I’m sure he would have suggested it. How would you describe their sound by the way? Good for all sorts of music like anything from classical to heavy metal and emo? Or better for ooh so warm vocals and acoustic stuff?

Never heard them.. (but wish I have). However, expect a dynamic quick and clean character (..i.e. "fast") due to the low mass for the given sd. Considering eff. (motor strength) it should be fairly force-full even though the mass is quite low. The other drivers will have more subjective "punch" in the midbass due to their greater mass - BUT they won't be as "quick and clean".

If you want more discriptors I'd ask Nielsio for them.. (perhaps on his thread to alert his attention?)

I personally use a pair of pro 10"s that are likely similar to what eminence offers (i.e. more punch at the expense of clarity and "speed"), but they are not being operated that high up (only to around 300 Hz with -6db after that). (..on the other hand they cost a considerably less - and no you can't get them now).

Oh, and despite what others might suggest with "cheap and cheerfull" dipoles - the more massive and rigid the baffle, the better the sound. (i.e. think concrete.) ..pardon the pun, but it makes a MASSIVE difference.

[Tenson]

Ahh so much for doing this sort of thing late at night, I was looking at the wrong sheet on the spreadsheet! The Supravox does not have higher max SPL after all... not surprisingly.
I think some of the Tannoy monitors used similar expensive ‘PA’ drivers and are very highly regarded.

[ScottG]

Originally posted by Tenson
Ahh so much for doing this sort of thing late at night, I was looking at the wrong sheet on the spreadsheet! The Supravox does not have higher max SPL after all... not surprisingly.
I think some of the Tannoy monitors used similar expensive ‘PA’ drivers and are very highly regarded.

No. The supravox will have a higher max spl within its linear operation for the desired passband. (.. it has higher x-max and is more eff. at lower freq.s on an open baffle - needing less eq.)

For the application you have suggested (even considering eq.) - this is THE driver at a moderate price.

[Tenson]

Okay so after realising I was looking at the wrong sheet on the spreadsheet I have gone over the last few woofers I looked at again.

Here is a graph for the MAX SPL of the three best vs. the Supravox.



As you say the Supravox will have higher SPL within its linear operation as it has a higher efficiency, but I have EQ and however much power I need so... that doesn't really matter.

Out of these three 'top picks' which do you people think has the best over-all sound for midrange?

Thanks!

[Tenson]

Okay, I think the Supravox could cut it. With the extra 6dB my fill in woofer will give that should be about 104dB @ 40Hz @ 1m. Thats about 93dB @ 4m distance isn't it, I think!? Sounds like it should do for all but the most SPL crazed weirdo’s!

So... is there anywhere I can hear these divers near me? I am in Kent. Anyone kind enough to let me have an earwig?

[Bose(o)]

Well, since we're talking Open Baffles, let's get into Linkwitz-mind. Really, frequency response deviations that are slight won't matter as much if we have low distortion and good phase.

Have you looked on the web for distortion measurements of these drivers? I remember the Eminences running well, but I don't think the models in question were the ones being tested.

[AndrewT]

Hi Tenson,
would you care to take the time to explain what that display in post7 is telling us?

Why are there two roll off slopes at the bass end?
What is that blip at 150Hz?
Why is there a notch at 550Hz?
Why is the JBL different below 60Hz?
Why is there a roll off above 900Hz?
Why are all the speakers so similar?

Obviously there is a lot I do not understand.