Members drumrolls Posted September 18, 2009 Members Share Posted September 18, 2009 Hello, I just purchased a used JBL PRX 518S powered sub. Works and sounds great, but I am underwhelmed with the performance. I trust the seller is not trying to scam me (maybe I've been dupped!) I haven't hook up a ton of devices yet to try different inputs, but I am wondering - Is it possible for the sub to have some sort of defect that would limit it's performance? The sound is clean, no clipping, x-over and polarity switcing works, both left and right channels work. In my experience an amp either works or it doesn't and a speaker either sounds like crap or sounds good and clean. I just feel like this thing should be putting out some more thump. Thanks for any and all suggestions or comments! Link to comment Share on other sites More sharing options...
Members gspointer Posted September 18, 2009 Members Share Posted September 18, 2009 If you are not seeing a flash of the clip light, how do you know if you are driving it to its limit? Link to comment Share on other sites More sharing options...
Members drumrolls Posted September 18, 2009 Author Members Share Posted September 18, 2009 Correct. The red light never illuminates. Does that mean I need to send a stronger signal? i had input device maxed out and volume input on the sub maxed out (which I would never do, but it just got mildly louder... not what I expected) Link to comment Share on other sites More sharing options...
Members Renfield Posted September 18, 2009 Members Share Posted September 18, 2009 Try taking this issue up in the Live sound forum, you may have more luck than here in Bass-land. Link to comment Share on other sites More sharing options...
Members gspointer Posted September 18, 2009 Members Share Posted September 18, 2009 Correct. The red light never illuminates. Does that mean I need to send a stronger signal? i had input device maxed out and volume input on the sub maxed out (which I would never do, but it just got mildly louder... not what I expected) What are you using as an input device? it is possible that it does not have sufficient output to properly drive your sub. Link to comment Share on other sites More sharing options...
Members Renfield Posted September 18, 2009 Members Share Posted September 18, 2009 What are you using as an input device? it is possible that it does not have sufficient output to properly drive your sub. That's my guess too. Cranking the input gains like that is going to bring it into limiting prematurely, which explains the lack of output or change in output, he needs a stronger input signal. Link to comment Share on other sites More sharing options...
Members gspointer Posted September 18, 2009 Members Share Posted September 18, 2009 Wow, posted the same question in 5 forums. Link to comment Share on other sites More sharing options...
Members Renfield Posted September 18, 2009 Members Share Posted September 18, 2009 Wow, posted the same question in 5 forums. A sure fire way to get 17 different answers. Link to comment Share on other sites More sharing options...
Members drumrolls Posted September 18, 2009 Author Members Share Posted September 18, 2009 Yeah... sorry for mulitple posts... just signed up as a user today... can you tell? Anyway, I used an ipod with 1/8" to 1/4" jack, it didnt do the trick so I grabbed my Roland TD8 brain thinking it would push... was a wee bit better, but still I should not be able to turn the sub input gain to 100%. I think I agree that input need to be boosted. Will play with my mixer tonight. Thanks, Link to comment Share on other sites More sharing options...
Members Renfield Posted September 19, 2009 Members Share Posted September 19, 2009 Will play with my mixer tonight. I predict fantastic results from this idea. It will get the input impedance where it belongs. Link to comment Share on other sites More sharing options...
Members The Insomniac Posted September 19, 2009 Members Share Posted September 19, 2009 Have a JBL dealer in town? Drop in and see if the floor model has similar results. Too many variables to get a good answer here I would think. Link to comment Share on other sites More sharing options...
Moderators Kindness Posted September 19, 2009 Moderators Share Posted September 19, 2009 A stronger signal should fix your issues. Link to comment Share on other sites More sharing options...
Members rpsands Posted September 19, 2009 Members Share Posted September 19, 2009 +2 to the signal weakness comments. I run an Ipod/etc into the tape in in my mixer and sometimes it's still quiet - running straight to a power amp essentially is a recipe for super quiet, thin sound. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.