hornresp input for CUBO12?

[LORDSANSUI]

Hi Fredi, this graphics show everything, I mean, the cubo is an offset layout so it generates a lot of dips in the frequency response as we can see.
Looks like also from 500Hz to 7kHz the SmallHorn present higher SPL.

They were measured with the same driver?

 

[freddi]

Hi LORDSANSUI, Cubo12 had a PYM1298 (~same as Kappa12A) - Smallhorn I think had a Peerless Tymphany "Pro" 10" (if not then an Eminence 10 made for SWR)

 

[LORDSANSUI]

What is the volume of your cubo?

 

[freddi]

External bulk Cubo12 ~99 LITERS

 

[maxolini]

freddi,
so you wanted to see how low the cubo12 gone ? (70hz )
or just a home for your driver ?

 

[freddi]

- wanted to see how it did vs hornresp - I might still have a Dayton PA310. Those graphs were ~ 1pi loading. My horn by Bill Woods - does this in similar conditions

 

[maxolini]

What was your findings, horn resp matched?

 

[freddi]

there seems good agreement for the bottom - I think the folds may affect other portions of the response.

 

[maxolini]

Cubo series suppose to be subs, so below 120 who cares , looks like the sim resembles the real life very close

 

[freddi]

my builder friend liked Cubo12 run to 2K5 plus his only drivers are Commonwealth 12 and PYM1298.

@LORDSANSUI - is there a similar tapped horn to Cubo12 that is arranged so as to have less dips and thus smoother for high xover application?

 

[LORDSANSUI]

is there a similar tapped horn to Cubo12 that is arranged so as to have less dips and thus smoother for high xover application?

Tapped horn no, is the nature of tapped horn to have the driver offset, so I think this models is only for subwoofer and kickbin, but there are many BP6P that does not present this issue and will present high SPL output as TH. that is BP6S.

The back chamber is like all vented box, and the front chamber the driver should not be offset, even for models with offset front chamber, there is a way to remove this offset.

Check below, the models: Altec817, Splanar, Whorn, WMX, WLX will not have the issue once the driver are front loaded, so no dips. The models BP6P5, BP6P9 could be a good candidate to remove the offset and fix the issue too if you need wider bandwidth.

https://freeloudspeakerplan.rf.gd

Note: Some vent port could have the design improved to reduce port noise / compression.

 

[freddi]

my friend's observations and POV on the two cabinets he recently made are interesting

I believe he liked the Eminence Commonwealth12 guitar speaker better than the Kappa12A spec PYM1298

As you noted, the Cubo graph looked kind of K-ish, but the completed speaker has none of the K coloration, and the driver as the box presents it is backwards and sideways! I had low expectations for the Cubo's bandwidth; as you noted I also thought we'd be lucky to get over an octave.

Similarly, the Cubo has an open BR sound, and the Smallhorn, with its flatter and more extended midrange graph has a slightly hollow sound in comparison, and the seemingly small difference at around 60hz is immediately obvious. One box has thump, the other doesn't.

 

[LORDSANSUI]

Cubo has 12" drive while Smallhorn has 10" one

For sure you can get more thump building Smalhorn with 12" and extended horn length

 

[Brian Steele]

All subwoofer designs that try to use some combination of the front and rear output of the driver are going to suffer from phase-related response issues at higher frequencies that limit their useful bandwidth. This should not be too much of an issue for a good design, as subwoofers are typically used to cover a narrow range of frequencies anyway.

 

[LORDSANSUI]

This is the simulation I have for the Super Planar

40Hz in the low end and very wide bandwidth considering 15" driver.

phase-related response issues

True, but some models suffer more then others.

 

[freddi]

Is there such a thing as a "baby Splanar" - say for a single PA310 to get a taste of the concept? (A paraflex could be fun also)

IF I copied your input screen correctly:

15PZB40 lossy Le

 

[freddi]

BTW - in those recent graphs of CUBO12 and Smallhorn3 - Smallhorn3 was loaded with
the Peerless Tymphany 10" "Pro" driver.

 

[LORDSANSUI]

A paraflex could be fun also

Almost all paraflex has the driver placed offset so they will present dips in the response, maybe some of them could be fixed. Sometimes fixing offset can generate wasted space.

For frequencies higher them 300Hz maybe we need to be more careful with the horn bends and probably reflect panel will be required.

 

[freddi]

Here's a few dips from Cubo12 loaded with a 25lb Eminence Commonwealth 12 speaker (preferred vs PYM1298 Plye which was just like Kappa 12A).

Its compared to a powered sub with two cheap 12" Dayton drivers".

 

[grindstone]

Sorry late to this -- which one is the smallhorn 3 geometry in the list? Thanks.