How is mating Peerless 850467 w/ Vifa DX25?

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Hi guys,

I'm about to committ to these two drivers to make a pair of bass reflex floorstanders and decided upon this combo. The 850467 was reccomended by the good people here and after some sidetracking in the real world... am back and came up with this prelim design.

I decided to use the Vifa tweeter as it has a fairly low fs so i can cross at a lower frequency to avoid the Peerless woofer's very obvious peak. There seems to be some controversy over the measurements from DST and Stones Sound Studio so i'd want a good budget tweet with low fs just in case anyway.

I intend to cross the woofer at 3rd order and tweeter 2nd order at about 1.5 to 2khz. The enclosure will be 25L and tuned to 45hz. With baffle step compensation and lpad, the crossover is pretty complex and will need about 10 parts!

Any tweeter or crossover suggestions guys?
 
The box size you suggest with the tuning is fine. You get a nice bass response with a small 1 dB hump before roll off, 25% fill the cabinet and your flat so no probs there.

You dont need to specifically crossover that low with the peerless you can deal with the peak another way, althoug im not 100% sure this would work it could well do. Im not 100% au fait with technical terms but I think you call it adding extra damping to the circuit. But if you look at the attached pic and then at resistor 2021 thats in series with the shunt capacitor. This can pull down the response of the lowpass filter. The first pic is the best LSPcad pros optimiser can muster without the resistor in place. Add the resistor with a value of 2.6 ohms and pic two happens. Although not as servere as the peerless peak, this principle is the same. The last pic is if you increase the value to 10 ohms, so it does increase the amount it works significantly.

If you can pull this off, (get loudspeaker workshop, its free and sim around with SPL trace and peerless graphs for data) and can get the response to give the right roll off at a higher frequency the tweeter will thank you for it. There are few tweets that will do 1.5k with grace most would just hold up a white flag and scream at you to stop. A few more can do 2k and loads can do 2.5k, so if you can increase the xover point, you get the choice of many more tweets.
 
Round things in a sac, I forgot the picture!:D :bigeyes: :D
 

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Sure no probs I suppose I should have included that before. OK

R2031 and L2031 form the baffle step correction for this driver in its box.

L2011 and C2021 form the 2nd order lowpass network.
R2011 is the resistance of the inductor and LSPcap always adds it in.

The R2021 is the extra resistor I spoke about adding.

I hope this makes it clear.

Matt
 
How is mating Peerless 850467 w/ Vifa DX25........

First of all, mating the two would be unethical
and probably physically impossible, if you
could do it you'd get a twoofer or a weeter,
or a combination thereof with a very low chance
of survival beyond running in.
Just joking...........

Actually it would be a brave person who take on that
midrange offered by the 850467.
Is it too late to consider the HDS 6.5 inch 850594 or
the CSX 850122?, both a bit cheaper and easier to
cross-over (i.e you can tune it by ear)
just a suggestion!
 
Hi madinoz,

Oh yeah i've tried hard to come up with some sort of crossover that'll avoid the bump but unfortunately being in a budget, i've learned a very valuable lesson in life.

Cheap tweeters dont sound good crossing below 2k.

Unfortunately i've avoided the hassle (only this time, i promise, next project will not use predesigned stuff! ) and ordered the P17 and D25AG. The 850594 is in my sights and will be used in the next project.
 
C h r i s
Did you purchase the xt25 tweeters?
Did you try them?
Do you intend to use them with the Peerless woofer when
you get to use it?
If not do you want to sell two xt25 tweeters to a fellow
audiophile in Brissy??
Just though I'd ask,ask,ask,ask ( 4 questions that is)
Madinoz
 
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