I appreciate your input. I don't expect that live bands will be a big part of business, but if they are I'll add a dedicated system for them to use. With respect to my bass horn proposal, I have been thinking the same. Looking at the Diaphragm Displacement page of my sim, there is a 1 mm displacement at 20 Hz. If this is at the corresponding Eg of 2.83 RMS Volts on the Input Parameters page, and at the corresponding output of about 112 DB on the Acoustical Output page, I don't see the need for two horns. If I use a Lab 15 and put 400 watts into it, what will happen? I also don't see the need for the sort of purpose built subwoofer drivers normally used in bass reflex or sealed box subs. Why wouldn't a K-33 or similar be adequate? That said, this is not at all an area of expertise for me, so I may be missing something important.
If you want the BEST bass experience - go for a double bass array. It's easier to build but cost is higher.
Put some woofers where your horn mouth woud be and do some measurements in the room. To get at least an idea if it will work.
Normal live venues are pretty big and room modes are in a complete different frequency area. So positioning of the subs in your room needs to be more careful. It's likely that the position is fine - but I would not want to find out it produces a null at 60Hz after finishing the build ...
Put some woofers where your horn mouth woud be and do some measurements in the room. To get at least an idea if it will work.
Normal live venues are pretty big and room modes are in a complete different frequency area. So positioning of the subs in your room needs to be more careful. It's likely that the position is fine - but I would not want to find out it produces a null at 60Hz after finishing the build ...
your hornresp has a warning as you have no throat chamber, you will always have one even if its just the minimum to avoid the cone hitting the throat.
I'm just trying to tell you that at this stage designing for high output/worst case has low cost but if not considered it would have high cost. For example if the rear chamber is not made large enough to accommodate a high excursion driver it will be hard to fit one in the future. If provisions are not made for push pull drivers and stage vibration is an issue then a rebuild is required etc...
I'm just trying to tell you that at this stage designing for high output/worst case has low cost but if not considered it would have high cost. For example if the rear chamber is not made large enough to accommodate a high excursion driver it will be hard to fit one in the future. If provisions are not made for push pull drivers and stage vibration is an issue then a rebuild is required etc...
My plan is to have a much larger than required volume where the driver and back chamber is located. This will allow service and modification of everything up to the throat.
Output at 20Hz is about 104dB, the driver unloads below the horn Fc (cutoff frequency), hence the rapidly increasing excursion below the impedance and excursion minima.
.05 x Pi is eight space, or corner loading- your horn exit is loading to half space, 2 x Pi, so the sensitivity is overstated by 6dB. An increase of 6dB requires double the excursion and four times the power.
Put a larger voltage into the Eg to simulate higher power- 56.57 volts at a nominal 8 ohm load for 400 watts.
For clean output, a steep (24dB per octave) HP (low cut) filter is required to control excursion below Fc at higher power.
The K-33 is designed for a higher Fc, and has less excursion and Bl than the LAB 15 (or LAB 12) drivers.
The K-33 reaches its mechanical limits only 4.1mm after it's linear excursion limits.
This thread lists the old K33E specs if you want to plug them in to compare:
https://www.diyaudio.com/community/threads/klipsch-horn-woofer-designs.176729/
Name: 15162
Type: Standard one-way driver
Company: Eminence Speaker LLC
Comment: K33E
No. of Drivers = 1
Fs = 34.46 Hz
Qms = 7.39
Vas = 301.7 liters
Cms = 0.268 mm/N
Mms = 79.47 g
Rms = 2.328 kg/s
Xmax = 8.2 mm
Xmech = 12.3 mm
P-Dia = 336.6 mm
Sd = 889.6 sq.cm
P-Vd = 0.729 liters
Qes = 0.41
Re = 3.39 ohms
Le = 0.96 mH
Z = 4 ohms
BL = 11.93 Tm
Pe = 150 watts
Qts = 0.388
no = 2.903 %
1-W SPL = 96.78 dB
2.83-V SPL = 100.5 dB
weltersys: Thanks for your input. I have attached sims for 2 X Pi and the 80 watts from the amplifier that I will most likely use. I plan on using DSP on the horn sub, so a steep HP is no problem, and time alignment should also be easy. I will try the K-33 in a sim as well, using the higher Eg and 2 X Pi.
Hello tizman,
If you need help to develop a box or architectural plan to implement this exponential horn I can support you.
https://freeloudspeakerplan.rf.gd/
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This is why BPs rule!
djk quote, "I use 6th order vented alignments for minimum box size and maximum bass extension. These boxes sound so different than regular vented that they may take some getting used to the clean sound."
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maxolini: i am planning preemptively, it will be a while before building starts. I was hoping to get some input on the plan, and have received some great info. Not much yet on the sims above though…
the sims looks normal, as long you do not exceed Xmax below the bandpass you are golden.
although most people use 24dB BW filters instead of 48dB LR
i guess it has to do with the group delay but idk if that affects or no the actual perceived sound
the more step the filter, more phase artifacts , but i can not tell if you can "hear" or no the diference between 8th order and 4th order filters.
also if you use some acoustic lining in the back chamber it helps to tame the wavy response
HR tends to exaggerate the peaks and dips, according to the people who measured the freq response on the actual built cabinets.
although most people use 24dB BW filters instead of 48dB LR
i guess it has to do with the group delay but idk if that affects or no the actual perceived sound
the more step the filter, more phase artifacts , but i can not tell if you can "hear" or no the diference between 8th order and 4th order filters.
also if you use some acoustic lining in the back chamber it helps to tame the wavy response
HR tends to exaggerate the peaks and dips, according to the people who measured the freq response on the actual built cabinets.