10" top design - Open discussion

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I'm crossing my finger to David implement an improvement to hornresp to allow us to simulate different front resonator shape

Hi Marcelo,

There is still a fair amount of work to do, but so far things are progressing well - no nasty surprises yet :).

The next step in the process will be to add the new CH1 model to the Loudspeaker Wizard.

Kind regards,

David
 
LORDSANSUI,

Have you ever built or heard this "super-planar" design?

It is essentially a BP6 with little restriction in front of the cone, allowing the high frequencies to come through. I understand it's trick is how it's tuned, so as to fill a certain dip. It still sacrifices a smooth response for a peaky rise in sensitivity.

FWIW, I have some experience with a somewhat similar design, the Karlson. The way it's tuned, a Karlson can have tremendous mid/upper-bass power, but the response above its pass band suffers and the midrange does not always sound right to me. I think the "super-planar" will suffer in a similar way, especially concerning to me since you intend to use it for midrange duty. It might make a decent kick-bin if tuned lower though.

I think expecting 100dB@2.83V in 4Pi space down to 100Hz is too much for almost any single direct radiator. If you only care about high sensitivity and not efficiency, using two 8" or 10" would be the way to go IMO. You may get ~100dB in 2Pi space down to 100Hz with the right drivers. Other than a huge front horn, as you have discovered, all other solutions will compromise performance in different manners.

Still, if I try to give a shot to the "super-planar" in Hornresp, I can manage 100Hz-600Hz at ~100dB in 2Pi space with a single 10" Celestion TF1020 in a package less than a cubic foot, fairly smooth in the passband to boot. Maybe there is something to be done there, but we are operating with very clear performance boundaries IMO.
 
There is still a fair amount of work to do, but so far things are progressing well - no nasty surprises yet :)

Take all time you need. Even if you don't implement the proposal I will say thanks just just because you think about it.


I have some experience with a somewhat similar design, the Karlson. The way it's tuned, a Karlson

IG81, thanks a lot for your shared experience, I may need MMJ support to proper answer all your comments but in the mean while could you share what is the Karlson design you are making comparison?

When I think about Karlson i rember that there is an big obstacle in front of the driver, maybe these leads to a different behavior in the upper frequencies. The supper planar has no obstacle in front of the driver, so there is nothing that could attenuate upper frequencies at front radiation, but the resonator in fact as side effect can affect the upper frequencies directivity.

I can review the target, but do you think the best solution still BR or should I try to investigate other design?
 
Without proper measurements to confirm any theory we may run in circle :D

I still think that the MMJ proposal is different because the dip we see probably are only linked to the interaction between front and back waves. There is nothing in front of the driver to attenuate the upper frequencies and upper frequencies are very sensitive to obstacles. In this sense Karlson is a different story. Maybe the design closer to Super Planar would be Rear Loaded Horn that present the same cancellation (dips) behavior due to front and back waves.

Freddi, below you can find your two simulation compared to the Super Planar 10", one at 1pi as you made, and other as 4pi (as I'm focusing).

In addition, maybe hornresp is not much accurate to simulate Karlson design.
 

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There may be others, but the only driver I can think of that would be likely to yield close to 100dB in 2Pi down to 100Hz as a direct radiator is B&C 12PE32. The enclosure is 1cu.ft tuned to 100Hz.

Some 15" drivers might do it, but dispersion will suffer even more than a 12" at 1kHz+ if not before. As noted before my others and myself, dual vertical 10" or perhaps even 8" might just reach your goal.

Don't forget that baffle-step will come in this driver's range, likely somewhere below 500Hz.
 
IG81, I put all three conditions in the same graphic for your better comparison: 4pi, 2pi and 1pi and as you can see in 2pi the Super Planar Top is already over 101dB and with small EQ it's over 104dB, isn't seductive for a single 10"?

What 10" driver is this?

I guess stitching the red trace to the black one above ~500Hz might give a rough idea of system performance including baffle step. One could call that a "solid" 98dB. You're in a ~10dB window from 100Hz-1kHz, could be worse.

I don't know how it will sound subjectively though. There will be standing waves, mouth reflections, diffraction and HOM's. I suppose you really have to build it and evaluate if it works for you. Luckily one such enclosure should be a fast and fairly cheap build.

What is essentially a U-frame on a bass reflex, is here being used outside of its pass-band. The linear effects on the transfer function (shown in the above simulations) are not as bad as that of a Karlson, but it remains to be heard if the result is more euphonic than annoying IMO.

Be sure to post here if you build and evaluate this. I've built and toyed with many unconventional schemes and enjoyed the ride even if what I have today is way more standard.
 
It's a brazilian driver from a company named Snake.

Driver model: ESX310
T/S parameters
fs = 67Hz
Re = 5 ohm
Qms = 6,653
Qes = 0,192
Qts = 0,186
Vas = 28 L
Sd = 0,0314 m^2
Xmax = 4 mm
Le = 0,28 mH
BL = 17,37 T/m
no = 4,3%
mms = 28 g​
 

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What is essentially a U-frame on a bass reflex, is here being used outside of its pass-band. The linear effects on the transfer function (shown in the above simulations) are not as bad as that of a Karlson, but it remains to be heard if the result is more euphonic than annoying IMO.

.

The Super Planar uses a quarter wave resonator (not reflex) as the rear section , and yes , in this case a U-Frame as the resonator in front of the driver ..... It is compound loading with the high-tuned front resonator filling in the 4/4 cancellation of the rear QW section ... .

People have built the 2x12" version of the Super Planar tops and they like the results a lot but the baffle is shaped very differently on the dual driver tops ... ...

Nobody has yet built the single driver version so it is hard to say what the response, character, and polar behavior etc will be like exactly, it is all still an unknown ........ I would imagine it would have less dispersion than the dual driver system, but i cannot say for sure .. ..


Much discussion ,theory , examples , and build photos about the compound loaded quarterwave designs and compound loaded horns at this link:
Compound loading 6th order quarterwave "Super Planar" horns and pipes concepts/builds
 
It's a brazilian driver from a company named Snake.
Driver model: ESX310
T/S parameters
fs = 67Hz
Re = 5 ohm
Qms = 6,653
Qes = 0,192
Qts = 0,186
Vas = 28 L
Sd = 0,0314 m^2
Xmax = 4 mm
Le = 0,28 mH
BL = 17,37 T/m
no = 4,3%
mms = 28 g​

This SnakeESX310 looks like such a marvelous 10" PA driver Sansui ... Great parameters .... This company should consider exporting to the United States :D
 
those are cool parameters for horn loading - I've got a little Eminence made for SWR in one horn and also in a little K


05-RE OHMS 4.33 13-FS HZ 52.22

06-LE MH .74 14-MMS GMS 25.60

07-QM 2.94 15-CMS mm/N .3622

08-QE .250 16-RMS NS/M 2.8583

09-QT .230 17-VAS LTRS 68.19

10-XMAX MM 3.00 18-SD SCM 366.10

11-BL TM 11.99 19-EBP 206.2

12-EFF % 3.70 20-SPL dB 97.7
 
Backing from some time due to my baby burn and playing around with the new tool added from David to hornresp (thanks) here are some results.

CH1, it's a compound horn with front path having offset drive.

Considering the original proposal from MMJ to Superplanar top, the one I've been used in this thread and just adding flare in front of the driver in proves a lot the HF range but at the price of some lost in the medium frequencies. Probably it can also improve cab dispersion.

At the end the design became exactly a front load horn with big vent and short horn path.

Still in doubt about what to do, lets see
 

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