Why is there no punch from my JBL SRX728 subs?

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My sub has lots of punch now, I just wasn't getting enough level into the amplifier. I bought an Art Cleanbox 2-way stereo line level converter which converts signals from a -10db consumer equipment level to a +4db professional equipment level and its fine. Its not a punch in the chest so much, but a punch in the stomach, proving that the SRX728 sub is more of a sub than a bass bin. I'm gonna buy an SRX725 to put on top of it in Febuary so then i'll have that punch in the chest too. JBL recommended a 2ms delay on the SRX725 cabs and to run them full range.

Does anyone here own the SRX728 subs? If so, what amp or amps do you use to power them? I'm thinking about finding a used QSC PLX3002 or maybe a Crest CA12.
 
I like the way you say that haa haa, just automatically expecting me to be able to afford one without even thinking if I can afford one or not. Normally I could afford one, but its christmas, my 2 daughters want £500 laprop pcs for christmas, ALL the bills came in 1 week totalling £500, and the rent was due, £800, so i couldn't afford a dj mixer that was worth buying. All I could of afforded was a £50 one, which there was no point in buying because I want a Rane TTM56 when I get one again. So I bought the Art Cleanbox and its world fantastic. Plus it means I can now interface perfectly between any consumer equipment and professional equipment without having to lug around a big dj mixer. The Art Cleanbox is no bigger than my hand.
 
ok, just wondering why so much discussion for an obvious answer.

and no, I'm not looking for an answer to this post.
 
Whats obvious about any answer where my question was also :

What amp do you power your SRX728 subs with?
 
Ripper often times when asking a question and then going a totally different direction at times seems like sharing was snubbed. My ex wife was like that.
 
I may be thick, but i'm not immediately sure what it is you meant by that, sharing was snubbed.
 
Well I have found my solution to the problem of my sub having not much punch. But i'm just curious as to what amps people power their SRX728 subs wit, if in fact people on this forum actually own any SRX728 subs. I guess what I should be asking is this :

What amps you guys power your subs with?
 
I know a lot of people use the transformer amps to power subs because there is this belief that switch mode amps aren't that good at powering subs, but to be honest, i've seen tests on the next from professional audio tech guys who've shown results that show that switch mode amps are just as good at powering subs. I'd love to find a Crest CA18 to power my pair of SRX728 subs, but they're rare.
 
Jack the ripper said:
I know a lot of people use the transformer amps to power subs because there is this belief that switch mode amps aren't that good at powering subs, but to be honest, i've seen tests on the next from professional audio tech guys who've shown results that show that switch mode amps are just as good at powering subs. I'd love to find a Crest CA18 to power my pair of SRX728 subs, but they're rare.
Click to expand...

Like it's been discussed before....You would need 1 really big amp, (Qsc 6.0, Crown Macro-tech 5000, or 5002vz)

Or a switcher amp PER box. (QSC PLX 3402 or PLX 3602, Or Crown XTI 4000)
Or if you can afford it..(Crown I-Tech's Or Lab Gruppen FP6400, Or a QSC PL380)

Those boxes sound fantastic when run (2) off of a Macro-Tech 5002vz.
And yes, I've mixed with them while using the Macro-Tech's

Those Boxes are dual voice coil, THEY LIKE LOTS OF POWER.

Don't want to feed them what they want?? The sound will suffer.
 
Jack the ripper said:
I know a lot of people use the transformer amps to power subs because there is this belief that switch mode amps aren't that good at powering subs, but to be honest, i've seen tests on the next from professional audio tech guys who've shown results that show that switch mode amps are just as good at powering subs. I'd love to find a Crest CA18 to power my pair of SRX728 subs, but they're rare.
Click to expand...
Actually, switching amps have been recommended for use with subs or bass bins for years. The switching noise isn't an issue with the new amp models... but with the earlier Class H amps, it was. A bass cabinet wouldn't reproduce the switching noise anyway. :)
 
I'd like to hire a Crown MA5002 out to try out to power my subs but there's nowhere round here near me for 120 miles that has one to hire out that I know of, and i've searched in google and yell.com for hire places. The reason I thought about a couple of Crown K2 amps bridged is because i've read reviews of them being excellent due to them having a tight punchy sound and being 'perfect' for subs. I had 4 JBL MP418 subs about 8 years ago powered by a QSC PLX3002 and it sounded damn good, although I had to run it hard to get the awesome sound out of it that I heard. But funny enough i've read a lot of bad reviews from customers about them having used the PLX3002 on subs and thought it didn't sound too good at all.

I run my events from 9pm-5am continuous and all the music I play is very, very bass heavy oldskool rave music from start to finish, so I didn't wannt to overpower the subs. But seeing as the Crown MA5002VZ are rated at 1,700 watts per channel into 4 ohms at full bandwidth (20hz-20khz) then it should be pretty good. I've heard so many good reviews about the MA5002VZ sounding like it was just simply made for subs.
 
I use the Dynacord amps that came with my setup also.

Get an RMX 4050 or 5050, run in stereo one cabinet per channel, and your JBL's will thump.
 
There's no way in hell i'd use Crown K2's bridged mono for subs of that nature.

1.) Not enough Power

2.) They Have NO FANS!!!

3.) THEY HAVE NO FANS!!!
 
I've read loads of reviews from customers and on 2 pro audio websites that say they were damn good, and excellent at powering subs. The high damping factor helps to provide a tighter sound and the sound quality of them are suppose to be excellent too. I know that damping factor has a greater effect when cable runs are really long, but reviews say they have a lightening fast tight sound. Plus I run my events from 9pm-5am continuous with oldskool rave, the same style as here :

YouTube- Bizzy B & Technochild - Obsessions

That style has truly awesome hyped low frequency output on it, so I dont wanna put the subs under too much stress with that amazing bass for the 8 continuous hours that my events are run for. The fact that they have no fan just means that I might have to have some cooling in the racck to help with cooling, but that's simple. But anyway, my choice is simply between s Crown K2 bridged or a Crown MA5002VZ in stereo, but with mono cables running to the MA5002VZ.
 
I never put my speakers under too much stress, but with the serious amount of 30-45hz bass that the above style of music has in, the volume is much lower so you need twice the system as what you would need for a highly compressed dance track which would be pretty loud. The above style eats subs for breakfast and spits them out due to the basslines from as low as 19hz (there's an LTJ Bukem and DJ Peshay song called 19.5hz for a reason) are long continuous lines, that onoy change note with the melody, unlike the single stab sinewaves that dance music has underneath the kick drums. With these long sub basslines, i'm just worried that they're gonna damage my subs with me putting the same kind of power through them as you would rock or normal dance music with repetative 909 kick drums.
 
Jack,

It sounds to me like you have it all covered! And certainly appear to know more than anyone else here on the subject.

I just have one question............ Why did Crown stop making the K2?
 
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