Opinions needed on Tapped Horn drivers

[zobsky]

This is for home theater purposes, so the required response would be between 20 Hz and 80 - 100 Hz.

I have a bunch of drivers in my stash that could work, I'll post my horn resp sims later in the evening, but from simulations with a low frequency knee of between 20 - 25 Hz,

My DVC 4 ohm / 20 Hz / 15 mm xmax Adire shiva mk IV 12 seems to work in a negative tapered TH (T-TQWT), relatively compact at about 100 liters
http://stereointegrity.com/Files/OldAdireDrivers.pdf

My high-efficiency 8 ohm / 45 Hz FS / 3 mm Xmax PYM-1298 , ..clones of Eminence Kappa 12A seem to work in either a larger TH or more compact T-TQWT
Eminence Kappa-12A 12" Driver 8 Ohm | Parts-Express.com

I'm more interested in low freq. response than ultimate SPL, .. but I'm concerned about running out of xmax.

Any suggestions, opinions., etc .. ? As I said, I'll post sims later when I get back home.

[tb46]

Hi,

You may have seen the thread by Petter Persson:

http://www.diyaudio.com/forums/subwo...n-2x12-th.html

This driver modells well in Hornresp, and you can find it for under $100.--. Maybe a dual driver super SPUD on the cheap?

Regards,

[zobsky]

Here's a sample sim for the shiva . Opinions on potential real - life performance and excursion control?

[davygrvy]

looks good, make some sawdust.

I have a 15" Adire Tumult (34mm Xmax) just waiting for me to build a TH cab for it. I can model 'till the cows come home, or just do it and use it. And what you have looks great; go for it.

Watch 21 hertz for excursion limit and set your loudspeaker processor to hard limit the input voltage to the amp to prevent from hitting it. What's interesting with TH cabs, is excursion limit is in the passband rather than below for other types. With 2V shown as giving 97 SPL in 1/2 space, that should totally kill

[zobsky]

Tweaked the design by offsetting the driver , .. the benefit is mostly in reducing the group delay. Note that the frequency of max. excursion has moved to around 30 Hz. The 80 Hz peak can probably be addressed by stuffing the wider part of the line.

[tb46]

Hi zobsky,

Not trying to be contrary, but when I compare (@ 2pi/2V) this T-TQWT enclosure to a BR of same total net volume the BR seems to be the superior solution. Better frequency response, group delay, impulse response and excursion control. Not to talk about the ease of construction. So why go through the exercise?

Regards,

[tb46]

Hi,

Here are the input screens for Post #6.

Regards,

[zobsky]

Originally Posted by tb46

Hi zobsky,

Not trying to be contrary, but when I compare (@ 2pi/2V) this T-TQWT enclosure to a BR of same total net volume the BR seems to be the superior solution. Better frequency response, group delay, impulse response and excursion control. Not to talk about the ease of construction. So why go through the exercise?

Regards,

No good reason Seriously though, TLs sound subjectively better to me than reflexes, and my last expt with a T-TQWT a few years back was encouraging enough, so I'd like to try this experiment again. For a number of years, I had the shiva in a 145 liter EBS tuned enclosure tuned to below 20 Hz and it was great for home theater purposes as long as the main speakers weren't super efficient. When I went hi-efficiency, I had to dismantle that experiment

Just for kicks, here's a 20 Hz TL subwoofer set up of mine from even longer ago, paired with vintage magneplanars , .. eventually ended up being even taller. Sadly had to be dismantled due to several major room suckouts in that room of the house I was living in. Shorty after that, I gave up trying to get any form of decent sound from that room.

looking for BIG sonotube transmission line advice

[tb46]

Hi zobsky,

I think I get it, have you considered a large TH for the Shiva?

Regards,

[zobsky]

Originally Posted by tb46

Hi zobsky,

I think I get it, have you considered a large TH for the Shiva?

Regards,

Yes, I did but the point of this T-TQWT was to desgin a smaller tapped pipe at the expense of some efficiency loss. In any case, I don't think the shiva is the optimal driver for a tapped horn, ..though it can be made to work.