Advice on JL Audio 15W1-8 sub

Hello everyone, I am seeking this communities knowledgeable advice. I am wondering if it is worth trying to find an amp that will power a jl audio 15w1-8 subwoofer.
link to specs:
https://www.manualslib.com/manual/490247/Jl-Audio-15w1-4.html
(Edit: The images are in post #5)

I have two of the jl subwoofers with one currently in a box. Both subs are old and have not been used for 15 years plus. I had purchased them for a car back when I was in high school.
Box cubic feet appears to be 1.71, which is below the recommended size for the woofer.

I tried hooking up the one subwoofer that is currently in a box and was disappointed with the results. I bought fosi amp linked below based on the amazon reviews but it seems it does not have enough power at 8 ohms to drive the subwoofer. At full volume on the amplifier and with boost of 4 db using voicemeter banana on my pc it still seems underpowered. It is better with the 4db boost but seems lacking as the volume goes up on my old loudspeakers.

Fosi Audio M03 200 Watt TPA3255 Subwoofer Amplifier Mini Mono Channel Audio Power Amp for Home Theater Full-Frequency and SUB Bass Switchable with 32V/5A Power Supply

https://www.amazon.ca/dp/B07VHG2LR9?psc=1&ref=ppx_yo2ov_dt_b_product_details
I plan to return this to amp to amazon.

Use:
I would like to use the sub mainly for music but I would be open to building a better box for the second in my living room for movies.
Music: 80 and 90s dance music, some classic rock

However, I know my wife will not appreciate a 15inch sub in the living room. She is a fan of bose and their size of the speakers.........She thinks that they are too much and is happy with google home. I am currently borrowing a bose lifestyle 35 system from my father. I previously had a lifestyle 28 that failed.

I plan to put the one sub in a 14x16 room. It will be paired with two 3-way loud speakers with 12 inch drivers (midrange is only original speaker in the box). I currently power them with a rotel-1312 that never goes past half volume. Link to amplifier https://www.hifiengine.com/manual_library/rotel/ra-1312.shtml.

Looking for:
I am looking for a lower priced amp to add to this setup if you think the subwoofer is worth investing in. I have tried looking for subwoofers on kijiji but have not found any well rated sub for under 500 as I am looking for Canadian options. If I am to get another amp I would like it to have speaker inputs as the rotel doesnt have anything to output to the sub.
I would like to avoid using my computer and just use chromecast audio to stream music, or an old cell phone loaded with music, or streamed from plex.
I have the equipment to build another box if needed but it would obviously add to the overall cost. I also have a 3d printer if required and can do basic modelling.
I did take a look at winisd but I am still trying to understand it.
1691698144177.png


Any and all help is appreciated. Thank you.
 
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GM

Member
Joined 2003
Greets!

As you can see from the plot it's designed for lots of room gain if not vented and it needs to be up to nearly 10 ft^3 tuned to Fs or lower depending on room location to effectively use EQ and/or drive it to movie LFE SPLs with only 150 W.

As for amps, no clue, I'm decades out-of-date, so if forced to find one it would likely be used at a swap meet or yard sale.
 
Thanks for the response, I have took a chance on a gemini xga 5000 (Link to device) as it should have plenty of power. I hope to use equalizer apo with it for the low pass filter and probably swap the fans on the amp. It came out to 200 cad. If anyone has any suggestions for a budget sub that would work better in a smaller box it would be appreciated. 10 cubic feet seems quite large for a box to work with the subs I have and not something my wife will approve of.
 
You're welcome!

FYI/FWIW/YMMV: Clicked on the driver link the other day, looked at specs, but didn't DL, but today it got me some sort of 'Defender' virus?, locking up my laptop and loading other notices/links? that AVAST! apparently failed to deal with (or did it to 'force' me to pay them since I use its freeware?), saying I had to call some phone number for them to give me instructions to unlock it, so did a 'hard'? reboot (disconnect everything for awhile), so please post a copy for me to DL.

Yeah, even assuming it's a bogus rating, the driver is likely only going to be able to ~ safely use +3 - 6 dB (3 - 600 W) and even then only on 'fast' (time wise) transients.

Basic BR math shows that Qts' dominates until Vas becomes quite large, so with a high Qts' for a vented alignment where @ ~0.4 Qts' (and likely higher, measured), then Vb = Vas, Fb = Fs, so with a very high Vas also it's got to be big to get the most out of it, so the smallest I'd normally recommend is the pioneer's Vas/1.44 tuned to Fs.


Vented net volume (Vb) (L) = 20*Vas*Qts'^3.3 (Ft^3 = (Vb)*~28.31685)

Vented box tuning (Fb) (Hz) = 0.42*Fs*Qts'^-0.96

(Qts'): (Qts) + any added series resistance (Rs): http://www.mh-audio.nl/Calculators/newqts.html
 
I am sorry for the problem, you should not have had to download anything as it was just a picture of the specs. I think I did not have the same issue due to my ad blocker. I cant seem to edit the post to fix it. Perhaps an admin can. Once again I apologize as that was far from my goal with the link. I am going to do some research to understand what you wrote better. Thank you. Edit: I have reported the post to have it fixed.

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When I click(ed) on it, it was to DL the manual, but didn't try either time, though have over time DL'd many from a 'clean' version, so was rather surprised considering how long it's been around. Regardless, based on your experience I'm 'leaning' towards my other reason as this isn't the first time this sort of thing has happened on other sites. :(
 
If you havent already, consider https://chrome.google.com/webstore/detail/adblock-—-best-ad-blocker/gighmmpiobklfepjocnamgkkbiglidom

Also please dont pay anyone to get rid of anything. You may want to check your browser extensions or your notification settings as you likely clicked on one of the ads for the website. If you are still having trouble let me know and Ill walk you through it.
Link to how to manage extensions on chrome: https://support.google.com/chrome_webstore/answer/2664769?hl=en#:~:text=extensions'%20permissions%20anytime.-,On%20your%20computer%2C%20open%20Chrome%20.,the%20top%20right%2C%20click%20Extensions%20.
 

GM

Member
Joined 2003
Thanks! Honestly, thought Avast! protected me from these, i.e. it will block me from going to a site, clicking on a link, etc., with 'Blacklist' usually being the problem even with websites I've been to many times over the years in some cases with no way to get around it AFAIK.

I use to have an ad blocker, but it became obsolete and with Avast! it hasn't been a problem till now except for the 'Blacklist' ones it has been protecting me from.

Yes, first thing I was told long ago was never click on suspicious ads and never pay anyone except if having to take it to a proven local repair shop. Fortunately, unplugging power, removing the battery and rebooting using line power worked fine, though in searching Avast!, couldn't find anything to indicate there had been a problem other than the usual obsolete, etc., stuff it shows after every scan that I'll have to pay an annual fee to remove/correct. :(

Thanks for the info/offer and will have a Chrome look-see; I've noticed quite a few updates to various options + new options in recent months, but as long as it works, figured all was/is well, so not one to 'mess with success'. ;)

I looked at browser extensions, notification settings and all looks right to me and will try ad blocker when I feel more adventurous as I've been 'burned' so much early on that I'm really 'gun shy' at this point, especially now since Covid (not really, but listed as reason for death) took my two gurus that kept all my electronics working as required and don't trust any of my computer savvy neighbors for various reasons. Old age paranoia sucks big time! :cuss: :headbash: