Attention Raffi and Till (Roemhild)

[ConExp]

Hi,

I posted this message a while ago but did not get any answer.
If you are interested, please find my question at the link.

Thanks,

http://www.diyaudio.com/forums/showt...351#post973351

[Scottmoose]

I did some basic dimensions for something similar here: http://www.diyaudio.com/forums/showt...247#post975247

See post 6. It's not drawn, and this is a rough 1st pass -I'm currently, amongst a few other projects, working on a more refined version. No drawing -that you'd have to do for yourself, but the dims needed are there. Might be of use anyway.

Regards
Scott

[ConExp]

Thanks Scott,

Interesting. I designed a double horn (to enable large mouth), rear fairing (for corner loading), based on the parameters of the Fostex factory design (for the 206esr), this is kind of huge – 2 meter high.

I run simulation using Hornresp 10.0 (with very similar parameters) and got different results than you. There is a dip in the FR at ~100Hz. Once more, if I “force” the path length between the direct radiator and the moth to be short (50cm or shorter), the dip vanishes.

Any additional thoughts?

Thanks

[Scottmoose]

It sounds huge!

Without knowing the exact dimensions you were using, it's difficult to say why you're getting the dip. I don't know HornResp very well, and I have suspicions about it's accuracy -I use Martin King's MathCad worksheets instead.

I'm probably being more than usually stupid, but I'm not sure about the sort of horn you're modelling -was it a BVR type, or a (sort of) doubled version of the Factory horn?

[GM]

Greets!

Assuming I understand the question........ IIRC Hornresp assumes a straight FLH without a rear cover (no compression chamber), so it calcs the dipole cancellation between the driver and mouth whereas MJK chose to assume for ease of programming that the mouth and driver's output is emanating from the same point, ergo no dipole cancellation, only pathlength differences through the horn.

Is the distance from the driver to the mouth ~68" (~173 cm)?

GM

[Roemhild]

Hi


sorry I havent been here for a while.

Originally posted by ConExp
Hi,

(.....)

Could you draw a first guess of a BLH for FE206ES-R using your design concept?

Thank you,

sure I will try to make a design tonight and post it here.


regards Till

[Roemhild]

hi

my first try:

BL-Horn

length: 0.95m
throad: 95cm²
opening: 2800cm²
volumen: ~40liters

[Scottmoose]

Nice response. I'll have a look at that in MathCad over the next day or so out of interest.

[Audio_idiot]

Hi Roemhild

I'd been following your design concept since last year. I believe it's an excellent concept and just couldn't resist to build one for experiment.

Unfortunately, I do not have any of the drivers you simulate, the only decent pair of drivers I have is as follows:-

Coral Flat 6B
Parameter
Fo 68Hz
Qms 5.671
Qes 0.433
Qts 0.402
Vas 31.346 L

Could you kindly do a BL-Horn of your resonance theory model for me please.


Cheers

[Roemhild]

Originally posted by Audio_idiot
Hi Roemhild

I'd been following your design concept since last year. I believe it's an excellent concept and just couldn't resist to build one for experiment.

Unfortunately, I do not have any of the drivers you simulate, the only decent pair of drivers I have is as follows:-

Coral Flat 6B
Parameter
Fo 68Hz
Qms 5.671
Qes 0.433
Qts 0.402
Vas 31.346 L

Could you kindly do a BL-Horn of your resonance theory model for me please.


Cheers

Hi


I will try my best and post the result tonight.


cya Till