Plan request: A Traped horn to go from 35(ish)-120 w/RCF L18P200

[NEO Dan]

Along similar lines.
Not so micro tapped horn..... - Speakerplans.com Forums - Page 7

Sony 5" + RCF 21" + Beyma 18" = confusing thread

 

[epa]

tnx neo
in post 24 are the hr inputs of tobiazz moddel.
i recalculated it later because at the begining of the horn it opens a bit more.
it wil actually plays 1,5 herz lower according to the first sim..
i also moddeled it the "cubo" way,wich shows aprox the same response in the passband.
this type th works pretty good with this rcf driver.
erik

 

[epa]

@ richard
grey line is the rcf driver ,black is your woofer.
these inputs wil get you started.
note, i dont know the le value so thats just a gues.
also i dont know the x-max value so i can't model how much output it wil give .

 

[NEO Dan]

Specs:

 

[epa]

hi dan
i was replying on a pm richard send me about the ultrabas 18.
wich driver are those specs you gave?

erik

 

[ultrabass18]

Good Day All,

Hi Epa, Thanks for your HR data input and simulation. Le is 1.9 mH at 1 KHz and Xmax is 5.5 mm based on Hvc - Hg / 2 . But if we follow the RCF standard as Hvc - Hg/2 + Hg/4 . It should be 8.5 mm.

Richard

 

[NEO Dan]

The specs above are the RCF L18P200-N

 

[epa]

ok tnx for clearing up
richard it wil put out ~ 126 db@x-max(8.5 mm)1 box 2 pi.
responce looks smooth.-3db @34 hz

 

[Djim]

If you want to push out 126dB from 8,5mm you will need quiet some power cause that drivers suffers from serious pwr compression. That's the reason why this driver gets fried very often. Actualy for us it is the number one in recone sales over the years.

 

[ultrabass18]

To Erick( EPA). would you tell me what software ot program u use for drawing details as on subject no 31.


Cheers

Richard

 

[epa]

To Erick( EPA). would you tell me what software ot program u use for drawing details as on subject no 31.


Cheers

Richard

hi richard
i use autocad 2011.

 

[ultrabass18]

Good day ,

Djim , thanks for your comments but i don't really understand what u mean with power compression. I'll be gratefull if u can explain to me in easiest way.

Regards,

Richard.

 

[Djim]

Hi Richard,

Power compression are the losses of energy by:
1.) heat development (thermal power compression)
2.) mechanical losses (dynamic power compression)

That means the more power you are feeding the higher the losses become. Most PA drivers use to suffer from 3dB to 4.5dB power compression at Xmax. This means you need at least 2x the power to get there. These days the latest generation extended LF drivers suffer a little less from power compression (still more then 2.2dB at Xmax).

 

[maxolini]

Guys,
i was looking at this thread, does somebody have the pictures that EPA posted as the final plan for the OP cabinet
his pics just show .jpg but not picture

post #21,27 and 31

strange thing is that BJORNO pics shows ok