To friendly hornresp guru..

Is that possible to find out with hornresp?

Yep.

To be honest it would suprise me at all if the Kappa Pro 15LF wouldn't reach Xmax at just 600 Wrms in the Tempesthorn (now that I think about it, that goes for 300 Wrms aswell).

A speaker reaching Xmech can be heard if you're pretty close to the box. Hearing how it exceeds Xmax would probably need superhuman hearing (talking about folded basshorns off course).

Could it be thought that there is some kinda front chamber? Where does the first segment begin?

There is pretty much always a front chamber since the air in the cone can be listed as frontchamber.

It's sometimes pretty tricky to find were the horn starts and the frontchamber ends. In this case I would say that the horn starts in the centre in front of the driver (at the baffle not conus) and the frontchamber the space before that. But perhaps someone else thinks/knows different?

In first case you could just simulate as an exponential horn, with S1 being the area at the throat and S2 the mouth area. Dividing the horn in conical parts would give a less nice result in SPL-response tho and perhaps also in Xmax, but it would give an good idea anyway.

You could always mail Adire/Dan to ask for the specs as he used it. Come to think of it, do that before you start calculating. Previous experiences from myself would be that you can get easily a 10% marge in specs if you calculated roughly yourself.

but it's impossible to simulate the cabs with tempest parameters since adire publishes mainly Fs Vas Q, etc

Than how the heck did I end up with the Tempest as one of the drivers in Hornresp  ?

Ok tell you why:

If you doubleclick on the field were you put in the required T/S-parameters, you'll find that you can calculate RMS. CMS, BL and Mmd from other T/S-parameters, which you do have. Btw. You'll have to calculate in a specific order as you'll find out yourself anyhow.

For lenght draw a middle line in the horn. Actual path would probably be slightly longer since bending increases hornlenght. Remember mail Dan first (say you use Hornresp), don't know if someone replies but it will save lots of time if so.

VTC is Volume Throat Chamber (it's in cubic cm, so 1000 for 1 ltr), ATC is the Area at the beginning of the Throat Chamber, make it Sd in this case (my quick guess).

Leave FR and TAL blank (won't matter too much). Make sure to fill in LRC (make it 20) or you'll simulated something entirely different.

1 cab at 1,0 pi would be the same as 2 cabs in 2,0 pi (just for response not power) 1,0 pi is also 1 cab on the floor and against a wall. Ussually it gets 2 Hz to 5 Hz of lower f3.

Btw. Found all this out in about a month, without help from outside, just simulating, trying and reading Help-function at least 25 times

If I can do it why can't you ...... OK OK I pretty much s*ck at electronics.

For now...

Good luck

Supposedly my simulations were wrong, but i didn't reach Xmech with 100Vrms (about 1250W@8Ohms). Poorest/highest result was 14mm diaphragm displacement, which would be still less than Xmech (28mm total from 34mm Xmech)

You're talking about Xmech, I'm talking about Xmax.

Normally you use a speaker within it's Xmax, sound is best that way and you have plenty headroom as safety. Beyond the Xmax less of the voicecoil is in less of the magnetic gap, so the further the speaker goes beyond Xmax the more it will loose control.

Hornresp simulates as if the speaker has full control over the cone in those 14 mm. Instead beyond Xmax (so 5,5 mm orso), the speaker will have less than 100% control, perhaps only 30% at 10 mm, who know's. Well we don't, so we simulate only with the facts we do know: Xmax.

Most horns I simulated reach Xmax at just 200-300 Wrm. Theoretically that is.

In practice music isn't the sinewave Hornresp is using for the simulation. Depending on the kind of music and lowcut, the actual powerhandling will be about 1 - 2 times as high.

The higher the lowcut is placed the higher the powerhandling. Some sinebass songs (d&B) will have close to zero tolerance on the simulated powerhandling. Normal popmusic will give a powerhandling that's about 2 times as high as the theoretical powerhandling. For tekno/techno/gabba I use about 1.4 -1.6

Cheers

I was after Xmech since i wanted to see how easily i can accidentally break them if i wanted to try them with more power..

As I tried to explain it's useless to simulated with Xmech. If the Xmax would be 7.5 mm for instance and Xmech would be 15 mm (one-way). If the speaker would still behave linear beyond Xmax it would take about 4 times more power to reach Xmech, but since the speaker looses control above Xmax it could well be that Xmech is reached with only the double power (or 6 times for that matter).

You just don't have enough facts to base any serious thoughts on that simulation.

I would say Xmech is a marketing-related invention. Excellent material for a manufacturer to put in big letters in an advertisement, but only something you can keep in the back of your mind while designing, not actually work with it.

(Taken the fact into account that true excursion won't be even THAT much due to VC going away from magnetic gap and power compression)

Perhaps I'm misreading this, but in my vision it looks like it would be exactly the other way around. If the VC moves out of the gap it will need less power for excursion.

Powercompression wouldn't save you from overexcursion (it did totally the opposite in my experiences).

@40Hz it was about 11-12mm. If i hi pass them somewhere around 40Hz I should be completely safe with amps having such power/cab

I hope that by now you will take the frequency where the Xmax is reached as your new lowcut frequency. Play it save at first, if you're unhappy with the results you can always look up to the limits. Instead of taking risks by trusting on a best case scenario straight away.

and the result was even better!

If you would try it again at a later time, chances are that you would even make more progress. Don't go over one night simulating. Let it rest for a few days and look again, changing every hornparameter and compare with the previous result with the comparisation-function.

Response isn't the smoothest available, but since i use them below 100Hz (currently -3dB at 90Hz and 24dB/oct slope), it's totally usable.

Alright!

Cheers

Xmech can indeed very usefull, eg. the Ciare 12 you use has an Xmech very close to its Xmax.

Cheers