I had a pair of wharfedales with a series 470uF cap on the woofer for that reason. Unloading is especially a problem with ported designs. Others more knowledgeable may be able to offer PXLLO, DSP or other solutions to over-excursion.
My current 3 ways have a 2 - 4KHz dip. This isn't to help off axis response as to tame the brightness of the Seas L15 metal driver I'm using as a midrange. It is one of the failed aspects of that design, is that I couldn't get it to sound right at any crossover frequency and slope. I tried from 1.7KHz - 2.7KHz (the lowest being the safest for the tweeter I'm using). The same tweeter was easy to integrate (lower order slopes too) with a paper cone midrange.
My solution was to lower the output at the crossover point (currently 2.3KHz) which provided the best compromise and easiest passive crossover design without going component crazy and getting the phase alignment I wanted.
With all its faults, the 3 way design has a clarity and detail the paper cone speaker lacks. I'm a sucker for a good metal cone and bass.... my next quest is to fine complimentary drivers with lower harmonic distortion. An RSS390HF / SBA17NBAC and SB26ADC combination is on the cards... although I might try a satori as a midrange in the above too.
When doing simulations, I always think validity is improved if more than 1 person arrives at the same result. I just had a chance to sim up my files albeit with slightly different baffle diffraction effects from Dave Bullet's, but I come up with just about the exact same results using his schematic values. Phase alignment is just about perfect with a nice simple and clean topology.
Nicely done.
Attached is with my files and Dave's xo in XSim.
Nicely done.
Attached is with my files and Dave's xo in XSim.
Attachments
Thanks. To be fair, my design wasn't actually mine. It was Douglas' topology with some adjustment values for increased BSC and a shunt resistor on the woofer capacitor just to help the slope for phase alignment.
I also like when other converge on a similar outcome using different tools and maybe tool setup methods. Provides some confidence.
I attach the RAW SB Acoustics measurements "factory" and data, plus the FRD files I used applying the baffle step and diffraction ripple of the enclosure meeting kristians layout preferences "in box" (woofer above tweeter).
NB: I lack the knowledge on how to apply an enclosure response to a factory impedance curve - so I used the SB acoustics ZMA files for both
(Remove the .TXT on all files)
If that is appropriate, here's an alternative..
Attachments
.I would be concerned with the files he's using or perhaps the woofer delay because I don't get the same results with my files. See below using Allen's values.
Phase is not well aligned and the FR looks a little too quiet from about 1500Hz on up.
Go with Dave's version.
Attachments
And what does this mean? Intentional - why? If you aren't going to explain, and are going to reference it in another place, could you possibly add a link?
No offense intended, but I find these types of drive-by-postings very unhelpful.
Correct me if I'm wrong, but is this for reduced distortion in that frequency region?
scratch that, I read further, I understand the concept. But doesn't it make more sense to apply that 1dB per octave slope actively through an eq, as it would make it more efficient?
Smooth (Flat) vs. Accurate (Hi-Fidelity) this is what I gathered this from, by the way.
note: that's a link to a specific post from that thread
note: that's a link to a specific post from that thread
And how exactly is that germane here?
The decisions were all made. As they say the trigger was pulled, and now were waiting to see if any post build corrections are needed. What is the point of second guessing it now?
Yes it does.
If you start building speakers with "voicing" built in, you only make room correction and EQ work harder after the fact.
Well I haven't made any purchases yet. I am a little confused and overwhelmed with all the crossover designs. There seem to be a lot of opinions on how to design the crossover for this build. I assume the answer for which design is best will be: which one sounds best in the real world when built.
I would appreciate if you could upload your .dxo files so I can take a better look at the designs and try to understand them a little better.
I would appreciate if you could upload your .dxo files so I can take a better look at the designs and try to understand them a little better.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.