I meant that the wider sweet spot of the JBL is nice but it lacks the impact of the 10F for the whole mid and highs that I would still prefer my 10F FAST box over the nice pattern of the waveguide. Now, if you could make a waveguide like that for the 10F, that would be quite something else.
Here is how I did the bootstrap snubbers on the TDA7492. Those are ceramic 330pF 100V caps and thin film 1/4watt resistors.
Here is how I did the bootstrap snubbers on the TDA7492. Those are ceramic 330pF 100V caps and thin film 1/4watt resistors.
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Wouldn't a three way be the ideal solution then. The fundamental treble tones are produced a lot lower than you might think. In many normal two ways, the bass driver is producing at least some of the treble.
The 10f has such a nice off axis response all the way out to 90 degrees that you could use it from 400Hz to say 4-5k and load a soft dome tweeter in a 4" waveguide to match the directivity of the 10f. That way the 10f still produces all the treble fundamentals, but you get the proper dispersion of a tweeter in a waveguide and that bigger sweet spot.
Taking you further away from the ideal full range output and fully into multi way territory 
. At least you could try the Duelund crossover technique.
And you'd be using the 10F for what it is advertised at, a midrange. Though in all honesty they do present them as wide band as well. Just not as a full range.
. At least you could try the Duelund crossover technique.And you'd be using the 10F for what it is advertised at, a midrange. Though in all honesty they do present them as wide band as well. Just not as a full range.
Optimally depends on what tweeter to use.
You should measure, instead of guessing
You can go as high as you want depending on what compromises you are willing to accept. A 3" is starting to beam probably by 3K, so 4-5K is already beaming. A waveguide may help keep the power response smooth, but you usually want to measure the tweeter in WG and mid, then xo where polar response is a good match.
Zaph|Audio About halfway down is the 10f with all the measurements you need
I bought a pair of these over a year ago to play with.
Dayton Audio AMT Mini-8 Air Motion Transformer Tweeter 8 Ohm
I saw an ebay listing the other day from china that seems to be this tweeter in a small waveguide, which has me thinking of making one to see if it actually works at all
Taking you further away from the ideal full range output and fully into multi way territory
Yep, squarely into multi way territory
just a suggestion though. On the otherhand, who cares if it's one driver or twenty as long as you get the best sound you can.
I say use drivers in such a way that their strengths are highlighted and weakness's minimized. The fast, if done right is doing half of it, but the upper end beaming, distortion and non linearity the full range is still in the mix
I mean, the chosen crossover frequency will depend on the tweeter, because we already have the woofer (10F). Cannot just pick arbitrary magical number such as 6kHz and force any tweeter to comply with that magical number.
The real magical number is where both woofer and tweeter will operate at their optimum performance (non-linear distortion, matched dispersion, FR).
First, measure all the woofers and tweeters in possession. Then find measurements of other tweeters not in possession. And then find the magical couple along with the best method to marry them.
I see what you're saying. I still say that just about any tweeter can do 6K unless it's got something seriously wrong with it. I'd personally probably choose a fairly inexpensive option if it's only going to be used this high. At 6K distortion shouldn't be an issue, it won't be rolling off prematurely at that point. The bigger question would be what you're willing to put up with in the mid as far as dispersion. We already know that the 10f is fine up high as far as on and off axis response and distortion.
I fully agree with you about arbitrarily picking a xo point because you want the mid to do as much as possible, but X does want the mid to do as much as possible, luckily he's using a mid that can do it.
Yes, all that is true. The real issue with setting a mid/tweeter xo high is the resulting poor power response. Take a look at the 10f off axis in the zaph blog I linked earlier and then look at the Heil's off axis if you have that. You'll likely see that the 10f is beaming a lot by then and the Heil is still pretty linear. So you end up with a dip in the upper mid/lower treble and a peak in the treble where the heil takes over.
Now I'm just explaining that it's more than just impedance and frequency response. I still think you could swing it considering the drivers you're using. Hell you already have everything, including the digital xo's. Just try it if you're interested!
If you do try it, try taking some off axis measurements of the whole setup to see what you get
Impedance and FR smoothness is "less" important. It is something that can be engineered. Matched dispersion and optimum HD is more important, because you cannot change it, you just need to "adjust" yourself.
Optimal XO frequency can be found from measured distortion. How many octave above resonance is only a guideline, will depend on the filter slope as well.
First breakup at 10kHz? Are you sure the harmonics doesn't affect it's distortion? 6kHz is less than an octave from 10kHz.
And like satx said, most probably the matched distortion is around 3kHz-4kHz, not 6kHz. It is matched phase and dispersion that will make two drivers operate like a single full range.
I think I will stick with the 10F and no tweeter. Listening to it tonight and really enjoying what I hear. The new TDA7492 amp sounds superb and seems to have more visceral impact in the bass and more resolution in the highs. Very nice speakers that I can live with for a long time. Not missing any highs or shimmer at all. Pulled out an old CD that really shines on this speaker - Oingo Boingo's Dead Man's Party. Hearing it like I have never heard it before. Elfman really knows how to mix some punch to the tracks.
hi X - would this transformer profide too much idle voltage for your 200W modules?
AS-4224 - 400VA 24V Transformer - AnTek Products Corp
AS-4224 - 400VA 24V Transformer - AnTek Products Corp