Help me choose a subwoofer driver for home theater

[Pete B]

@whoaru99 good point, I'll grab the model off the HT receiver tonight, I don't remember it off the top of my head.


Talking to the guys at CSS, they are recommending this speaker in a sealed box as small as 1.25cu.ft. It's a little more that I weas hoping to spend, but it seems like a really nice driver.

https://www.parts-express.com/CSS-SDX12-XBL2-12-Subwoofer-290-3006?quantity=1&msclkid=5a6a69be27741d57ea24031a3d216db2&utm_source=bing&utm_medium=cpc&utm_campaign=Standard%20Shopping%20-%20Speaker%20Components&utm_term=4583314296536342&utm_content=Hi-Fi%20Woofers%2C%20Subwoofers%2C%20Midrange%2C%20Tweeters

This kit also has me interested. With the flat pack, it saves me a bunch of time. I wonder if the performance would be similar to the CSS driver???

https://www.parts-express.com/Dayton-Audio-15-Ultimax-II-with-3-Ft-Cabinet-DIY-Home-Theater-Subwoofer-Kit-300-7222?quantity=1

That's an impressive subwoofer, you might ask PE to make a combo deal with whatever flat pack you prefer.
If you go larger around 2-3 cuft you can vent it with a very low tuning. You could put the box inside the
enclosures that you made I would think.

 

[whoaru99]

that is great news that it has the sub X-over. Does it also limit the main speakers from getting the lower bass?

As mentioned earlier, HPF and LPF are pretty much standard fare in HT receivers or pre/pros.

It's not unusual they have them, it would be unusual if they did not.

 

[Mr Boochie]

The main issue with them is they require 5 cu ft and ports.

I would be concerned about using Mr B’s Alnico 136a’s with your 500+ watt crown amp

The Alnico motors can loose some of their magnetic strength when pushed beyond say 200 or so watts

Thanks for the reference! A little more detail. These are 35-year-old DIYs. The 136A was one of the better 15-inch woofers available at the time.

I built mine to 4.5 internal cubic feet, acoustically suspended (no ports). A friend worked at JBL in the summer I built those subwoofers, and that's what their white paper said about building a subwoofer. He kinda snuck a copy of that paper out of work. They never made a standalone unpowered subwoofer in those days.

My subs run on a 250 watt/CH Anthem. It's the current that matters. You want your amp to have a good, clean current transient on tap for a tight, clean bass.

I had the tech remagnetize the Alnicos. He said that they didn't need it (kind of an overblown problem, as long as you aren't dropping the speakers). He charged $100 to do four 136A and one pair of 122A.

The subs worked really well with the main L300s (which also have the 136A woofer). Seamless, tight, not overwhelming or "obvious." I have no plans to replace them with anything else.

Cut The Cake.
Average White Band's "Cut The Cake." Atlantic Records. SD 18140. Monarch pressing, second variant. 1975.
Run-Out: ST-A-753399-DD (MR) AT △19898(7) PR

 

[Nyjblbob]

I had the tech remagnetize the Alnicos. He said that they didn't need it (kind of an overblown problem, as long as you aren't dropping the speakers). He charged $100 to do 4 136A and one pair of 122A.

That was then ! Mr. B
Now the only place in the US doing Re-mags is in Cali, that I know of.
When asked of Mr.Greg Timbers, JBL designer engineer JBL Alnico' 15's
Do loose magnetic strength when overheated, Over-powered, or dropped.
He did say the old style LE15-2215's are not effected,
due to their Extremely underhung
voice coil.
I used 200 Watts as a Low #. I regularly used to push my 136's and 2231's Hard
with a crown Power line 4. rated at 185 watts but tested by Crown at 256 watts rms.
No damage or loss of strength.
Music sources are peaky, and generally not continuous.
So No over heating in a normal Domestic situation.
Home theater with Massive special effects, is a different thing entirely.
Before I got my latest 4435 monsters i used a pair of Alon Thunderbolt subs.
Aprox 4-500 watts each. single 12".
When watching a Heavy Action film at Crazy levels, their heat sinks were extremely HOT.
sometimes going into protection mode.
We're trying to help Onebean build a Sub.
I doubt he's going to buy a vintage pair of Alnico drivers.

On the size JBL recommends and uses;
the L-200's L-300's, 4367's 4430's are listed at 5 cu ft. by the time you figure in damping material,
Crossovers, structural supports, drivers and horns, ports,
they are closer to 4 cu ft.
BTW I am a Huge fan of Alnico drivers.
There are NO dedicated NEW Subwoofers using them.
Not counting the $$$ JBL AL1500's

 

[Mr Boochie]

That was then ! Mr. B

I had them remagnetized at Speaker Repair Pro in OC, Calif. He measured them and said I didn't really need it, but gave me a special deal (I insisted on the remag) since I had a lot of speakers re-coned or new surrounds installed. He also scoped my crossovers.

I'm still happy with the setup. I have no plans to go to ceramic or neodymium magnet speakers at the moment.

Do you have any videos of your system?

Thanks!

 

[Nyjblbob]

No Video's.
They cannot reproduce the Low bass vibrating everything in the house,
Pictures falling, glass in China cabinets, doors n windows Humming.

 

[Mr Boochie]

No Video's.
They cannot reproduce the Low bass vibrating everything in the house,
Pictures falling, glass in China cabinets, doors n windows Humming.

That's cool! I like long-distance dusting of the joists! I usually record around 96dBA+/meter from speakers. This is to help eliminate the background noise. Noise, sound reflections, and cancellations are big issues in recording.

Good mics are the key to joyful tunes!

No worries!