understanding Void hybrid loading

[sgarfa]

I premise, to avoid misunderstanding about copyright discussions of Stasys X V2 , that the model has been in the sketchup 3dwarehouse library for a long time, my intenetion is not to copy (if one wants to do it,he would already have done it regardless of the correctness of measures),but understand how it works this multiple hybrid horn loading.

I have tried to set hornresp that simple model, of a folded horn with reflex tuned rear chamber (vrc minus reflex port volume), then exporting to akabak adding the "connection" duct and waveguide
the result was disastrous, did I set the problem wrong?


Dropbox - sez_void.jpg

 

[USRFobiwan]

Triple tuned design as it seems. Problem with void designs, they never show a graph.

Void did some clever stuff with allot of designs. See this crazy looking midbass cabinets of the new void nexus dance stack.

 

[sgarfa]

Dropbox - VOID IPOTETICAL.jpg

it is undoubtedly an intelligent project, anyway here it is the respose with and without the iteration of the 3rd port, I certainly did not expect immediately that it was all in phase, in a one-dimensional program like akabak, but I did not know anything like that, so I wondered if there was another reading key

 

[USRFobiwan]

try a different driver

 

[sgarfa]

mhh ... I'll try but I do not think that's the point

 

[Djim]

Hi sgarfa,

The impedance of the Void Stasys X V2 shows it is an 6th order BPH. To my ears BPH's can sound better than TH's, except around the low tuning, but such statement is cursing around here ;-)

They can be designed with Hornresp. Trick is to make the horn load working from 50Hz (or lower). Also keep a good eye on the efficiency chart in Hornresp to prevent the 'saddle' is too low. At 'war' volume a too low 'saddle' results in a smiley response.

Regards,
Djim

 

[Djim]

Hi sgarfa,

I have been corrected and it seems the impedance plot is from an older type. The V2 is an 8th order design.

Regards,
Djim

 

[sgarfa]

hi djim...if you see here is a probaby section of the v2...seems a quasi 8th order..hornloaded 🙂

 

[sgarfa]

strange respose(I'dont think it's entirely fair) ... but the indicate Crossover Point 38Hz Hi Pass 24dB/oct..its realistic with the simulted excursion of faital 18XL1600

 

[Djim]

Hi sgarfa,

The problem with these kinds of 'hybrids' is that they are difficult to model.
Your peak at 56Hz is the result of a 1/4WL resonance in your model, while in the 'real world' these kind of hybrids resonate down low at 1/2WL.

Regards,
Djim

 

[sgarfa]

hii...its possible to create the situation to simulate this behavior?

 

[Djim]

Hi sgarfa,

If you are good with Akabak I assume it is possible. I haven't seen many models of 8th order hybrids and the few I saw were just approximations that did differ from the measurements. Nonetheless, I doubt if software limitations were the reason for that ;-)
Did you tune the front ports of the Stasys to 28Hz?

Regards,
Djim

 

[sgarfa]

yes...but i see ..the "reflex" ports are not very important to the iteration...let me explain better ... at least within akabak, if they change their measurements (section and length) even by bringing them to small size( unrealizable), the response changes, but little...much of the work makes it the back horn loading, for this I justify the high cut (38hz)

 

[Djim]

Hi sgarfa,

The section that is named "Vtc", the front chamber, did you imply it as one large volume or did you spilt it up in two different chambers (parallel feeding the horn)?

Regards,
Djim