Sub-Woofer

[ChitoBG]

I thinking of having an active sub-woofer built using either jbl 2235 or 2245 with plate amplifier.

Do I need a single woofer or two? If I use two woofers, what are the advantages and disadvantages aside from cost of using single box (2 woofers) and double box.

Can you also make recommendation on the brand and model of plate amplifiers.

Thank you in advance for your expert inputs.

C

[grumpy]

Re number and placement, here's a fairly recent set of measurements and opinion:
https://www.harman.com/sites/default/files/white-paper/12/11/2015%20-%2006%3A12/files/multsubs.pdf

All of what you suggest has been done and published before (B380, B460, DIY 2245 in two sizes, dual 2235 in a huge box, ...)
Google is your friend.



Can you also make recommendation on the brand and model of plate amplifiers.

I've not used them, so not really. Use good construction techniques and a lot of bracing :)

[Ducatista47]

Can you also make recommendation on the brand and model of plate amplifiers.

Based on personal experience, plate amps die before they should. The new Class D models may have that problem solved. I use a JBL sub with a Class D plate amp, it does the job nicely, and my mind's logic tells me that subs benefit a great deal from this technology. Heat kills plate amps and Class D solves that. Vibration may be another matter. Since Class D hardware is mostly digital, my guess is another benefit.

I don't know if Parts Express goes to Manila, but they had them when I last looked.

[ChitoBG]

Based on personal experience, plate amps die before they should. The new Class D models may have that problem solved. I use a JBL sub with a Class D plate amp, it does the job nicely, and my mind's logic tells me that subs benefit a great deal from this technology. Heat kills plate amps and Class D solves that. Vibration may be another matter. Since Class D hardware is mostly digital, my guess is another benefit.

I don't know if Parts Express goes to Manila, but they had them when I last looked.

Thanks! Will do more research on Class D plate amps. If ever I can ask a relative to purchase form Parts Express and have it shipped to Manila.

[ChitoBG]

Re number and placement, here's a fairly recent set of measurements and opinion:
https://www.harman.com/sites/default/files/white-paper/12/11/2015%20-%2006%3A12/files/multsubs.pdf

All of what you suggest has been done and published before (B380, B460, DIY 2245 in two sizes, dual 2235 in a huge box, ...)
Google is your friend.



I've not used them, so not really. Use good construction techniques and a lot of bracing :)

Thanks on heads up and construction techniques recommendations!

[dezmond]

It depends on how low of frequency you want to go. If you ran 2 woofers in a isobaric box , you could get lower then a single woofer.

[grumpy]

If you ran 2 woofers in a isobaric box , you could get lower then a single woofer.

... in the same size box. And not play louder. And require more power. And you could just buy the right driver for the job to begin with.

I'd like to fool around with an isobaric sub sometime too, but not because it's a magic bullet.

[ChitoBG]

... in the same size box. And not play louder. And require more power. And you could just buy the right driver for the job to begin with.

I'd like to fool around with an isobaric sub sometime too, but not because it's a magic bullet.

My current system is 2405/2440 Hartsfield lens/k145 in 8 cu ft ported box tuned to 40 Hz driven by 300B amp. I feel I'm lacking the low end extension in some of the tracks.