R evenge C omes with F orce

[olsound]

RCF 21" tapped horn is it possible.

35hz to 110hz
Size 50"x45''x30''
folded style copied Epa design

Sim coming soon




Still trying to understand hornresp

some help would good

 

[epa]

you got my atention

 

[m R g S r]

you got me all excited for nothing!

 

[olsound]

Coming soon to a DIY near you


aka Do It With Some Help

 

[olsound]

RCF 21 Tapped horn

Hi everyone for the past few months I want to upgrade my sound system so I download horn response and give it a try , boy this thing is hard. Anyway with all the talk about tapped horn I said to myself I want to try something new enough with scoop, so I plug some numbers from the RCF21 driver in to horn response and get this



Epa design



My gold is to put 950 watt in the driver before reaching xmax.
My cabinet size is 45”x45’’x30’’
Frequency range 35hz to 110-20hz flat
The design I have in mind belongs to Epa .




Also if someone could help me with the folding that would be great. I have no knowledge of folding.
Please feel free to make any correction to this project.

Thanks


A little help goes along way

 

[epa]

i wil assist you.
the plan needs to be scaled up.

 

[olsound]

Thanks alot.

 

[epa]

are you shure about the size.
thats about 1000 ltrs.
thats much more efficient than your sim.
x-max is 8mm?
i did a sim that gives you 129db @8mm x-max with a peak of +130 db @38hz 750 ltr cab

 

[olsound]

1000ltrs that is big. Can we get 140-145db with 4 cabinet

 

[olsound]

My knowledge of hornresp is weak.

 

[Josh Ricci]

The RCF 21" that I am thinking of is 13mm xmax and 25mm xmech if I remember correctly.

 

[epa]

1000ltrs that is big. Can we get 140-145db with 4 cabinet

140 db easy with the 750 ltr cab.
dont forget that hr simulates sine waves.
with real music you wil get 145 db easy if you got enough power availeble.

 

[epa]

The RCF 21" that I am thinking of is 13mm xmax and 25mm xmech if I remember correctly.

i see it now.
this means that 145 db is not a problem,you wil be power limmited by your amps/circuit breaker.
i wil sugest a fold later on.

 

[olsound]

My amps is 2000watts per channel at 4ohm.
My power supply I built myself I feed the amps with a 40amp
145db sound good.
As we say the more, the merrier.

 

[Djim]

Besides costs and weight, the real challenge you will meet is to get a decent sound from it (acceptable group delay, high enough damping & impulse behaviour values, no extreme 'ringing' frequencies).

 

[epa]

My amps is 2000watts per channel at 4ohm.
My power supply I built myself I feed the amps with a 40amp
145db sound good..

yes but you lose a lot of power with power compression

As we say the more, the merrier.

where do you live?

 

[olsound]

Jamaica w.I.

 

[olsound]

the real challenge you will meet is to get a decent sound from it (acceptable group delay, high enough damping & impulse behaviour values, no extreme 'ringing' frequencies).

You lost me here

 

[epa]

Besides costs and weight, the real challenge you will meet is to get a decent sound from it (acceptable group delay, high enough damping & impulse behaviour values, no extreme 'ringing' frequencies).

hi djim
group delay and impulse look verry good,at least in the sim.
i added a chamber to damp the out of passband peaks a bit.
still think you need a power plant to get to the max of them

 

[Djim]

That the costs of drivers,amps, wood, transportability for such 21" dont weight against the advantages for building 2 x 18" TH's for each 21". Not only the cost, but in sound quality and SPL a 2x 18" will beat one 21" (or 4 x 18" against 2 x 21").

Btw, 2000 watts at 4Ohm/chan will never get you near 140dB...
134dB is more realistic from that power.