Passive into active

[MethMan]

Dear experienced
Need help with this:
PRE: I want to build a low distortion, good transient and polar response speakers, 3-way active w. 24dB slope. I will use a medium priced drivers (Seas Standard, Monacor, Beyma. No SS, Audax, Excel. Excel 001 only as a tweeter).
CON: Combining these demands lead me to let every driver play roughly 2-3 octaves, preferrably in closed box Qtc cca 0,57. Resulting in 4 kinds of drivers, crossover freqs say 200-1200-3600.
Q: Which drivers should be put together by passive crossover to ensure my demands?
MHO (could change of course): According to roughly simulated, predicted box and baffle steps configuration and loading it will be W-MW-M-T-MW. X-over 12dB for Appolito MW-M-MW and allows me to put T between M-MW

Thanks much for advice.

[uli]

I wouldnt do a 4way.
with 24dB slope you can xover at 150 and 3000 for a 3way.

Uli

[MethMan]

Even with fuzzy upper bass and 3% distortion or very terrible directivity upper mids.
Maybe you know some cosmic technology helium-rhodium based midwoofer which can play loud and clearly 150-3000.
200W, 93dB, under 60€, if possible Need only 2.

[uli]

Yeah, I forgot you are a genie!

You mean all the WilsonAudio stuff is ****?

Uli

[MethMan]

Of course not. But I can't allow expensive drivers to reach WilsonAudio quality. For my first step to 3-way design seems to me as wasting money. I have just accepted thesis from Linkwitz site that no one driver can play fine in your recommended region. Further studies of available driver's spec sheets confirmed it for me.
I just tried to find another opinion on problem. Find where the trade-offs is smallest possible. You also use 5 drivers and 4 kinds in your system. Isn't it? Maybe I finally find that the difference between pure active 3-way and my today's dream is none or it is even worse. If you wanted to say that I'm aiming too high I didn't took in - sorry for irony.

Peace

[uli]

Hi MethMan

I think that going active you have more choices than passive.

I always had trouble with the xover between lo mid and hi mid

in 4way systems therefore I now always try to avoid crossing over

in the region of the human voice especially around 1 kHz. Going

active allows you to equalize the midsystem (eg. 2x 6.5" like

Wilson). There are many 5" - 7" midwoofers which are perfectly

suited for up to 3 kHz. Cutting active at 150Hz with that steep

slope (24dB) allows you to use a really fat woofer going very low.

Good midwoofers are:

SEAS W17PPI about 75,- €
SEAS W171 EXP or EXGF about 75,- €
Monacor SPH 165 KEP about 70,- €
VIFA 17WP232/8 about 70,- €

Keep in mind that the lower you xover the higher the demand

on the tweeter.

Here is a link to a dealer in Germany, IMHO best prices in middle

Europe: LSV

Uli

[awboy]

Originally posted by uli
Hi MethMan

I think that going active you have more choices than passive.

There are many 5" - 7" midwoofers which are perfectly

suited for up to 3 kHz. Cutting active at 150Hz with that steep

slope (24dB) allows you to use a really fat woofer going very low.

And there are lots of very good tweeters that go down to 2000 or even 1500 Hz with low distortion if you use 4th order.
Peerless or even Monacor.

So why not go for two way say Peerless hd182 (or better 17 cm thing) +wa10 plus stereo subwoofers!

[5th element]

Id say a SEAS 27TDFC tweeter, Peerless HDS 5.5 or 6.5" without or with phase plug, your choice, for mids. Then a peerless 850146 10" bass in whatever alignment you choose.

This wont cost all that much and should hit good spl easy. But if you are after that REALLY high SPL then no normal hifi units are suitable. Some are an exception PHL etc.

Crossover as high as youd take the midrange or as low as youd take the tweeter, both have pros and cons. Or get a mixture of inbetween.

Bass mid xover is really very verstile, choose what you like.

[MethMan]

Thanks for your replies.
Originaly I wanted to accomodate 2" dome mid (Beyma MC115) between midwoofer an tweeter to cover peak of harmonic distortion at 2k and cone breakup mode at 2,7k of Beyma 5MP60N . Distortion of MC 115 is about -52 dB in 1,5K to 4,5k region, while 5MP60N is roughly for 8dB worse and has peaks to only -35dB. But remains true, that crossing in speech region is very problematic. You probably broked me. I choose better MW, because "easier" way can bring much better result for not so experienced. MC 115 I leave for future.