Big Enough Sub Or Not

[MobileDamo 0]

now then all you fellow bassheads lol

 

would a 1500wat sub be big enough for a medium to large gaff,my amp would power it at 900w and 1200 peak.many thanks

[NRG Roadshow 0]

Depends what you mean by medium to large.....

 

But on the whole I would say its plenty.....

 

But Im thinking your running the risk of frying your amplifier, amps are meant to be between 1 and 1.5 times the power of the speaker.

 

Are you certain its a 1500w sub......that seems a hell of a lot?

Is that 1500w peak?....you should really be looking at the RMS value of the speaker to calculate what amp you need to run it.

 

 

Edited January 29, 2008 by NRG Roadshow

[Karl 0]

Hya Mobiledemo it does depend on the size of your amp, with a sub that kind of power it would probably be wise to use 2 amps 1 for the sub and one for the mid and tops this way you will have less chance of clipping the amp.

Im assuming you be running at 4ohms so is working slightly harder to start with, we always run amps that are more powerful than the speakers basically so we dont run the risk of clipping, its better in my view to be able to hear if your over driving the speaker i.e. distorting then simply a case of backing of on the volume we also run at 8ohms so is also not being worked quite as hard.

[DJ Marky Marc 0]

it could be 10kw sub and not be good enough all depends on the speaker design. and other factors..

 

ive seen a lot of small cars with subs that clame to be 1000s of Watts and they wouldnt keep up with one of my bass bins..

 

Bass is also power hungry and as such you need more amp than speaker to get the best out of it..

 

each of my bass bins is a Dual 18" at 4 ohms rated at 1000w RMS, I drive each of these bass bins with its own amp in bridge mode giving me 2000w RMS of power for each speaker...

 

I feel the best choice for you would be a small bass speaker to match your amp or a bigger amp to match the bass speaker..

 

 

[MobileDamo 0]

Hello my amp will run at 8ohm bridged at 900watt and 1200watt peak

 

i miss read the specs for the sub lol

 

here we go then propa this time

 

THE RCF L18S800 18" WOOFER HANDLES 700 WATTS RMS, 1,400 WATTS PROGRAM & 6,000 WATTS PEAK POWER HANDLING

DETAILED STRONG BASS TONE WITH HIGH POWER HANDLING

THE RCF L18S800 18" SPEAKER IS OPTIMIZED FOR SOUND REINFORCEMENT SPEAKERS, BASS GUITAR, CLUB MUSIC SYSTEMS & ALL HIGH QUALITY BASS APPLICATIONS

 

 

I will be running this off a behringer 1280s powered amp in bridge mode along with a amp plugged into the main L&R on the powered amp to 2 top speakers.

 

Do you think i should get this idea outta my head and go for the good old seprate amps,eqs,crossovers ect ect

[UKHero 0]

It all depends what you want to do with your system but it looks good to me..... Oh must add is it an 8 ohm cab, I would think it is but best to check.

Edited January 29, 2008 by UKHero

[MobileDamo 0]

its for karoke/mobile disco use but i need that extra bit of juice their just incase i get a bigger booking like a marque or sumthing like that.

 

i am use to using big sound systems but i simply dont have the cash to start going out and buying crown amps and cerwin vega subs,also i dont wanna be wheeling in amp racks as tall as me into my gaffs i think that gives the wrong impress on mobilediscos and karaokes maybe a rave then yeh lol

 

I have just been on the phone to a dear friend of mine who i use to work for on the funfairs he is the man of all big sound systems lol

 

so he told if i was to run a 400watts speaker on my behringer 1280s with 450watts each channel at 4 ohm it will run the speakers perfectly without blowing them,

 

he said if you match the rms with the speaker or have the rms higher then the amp you will have enough power for the highs ect but when it comes to a bass kick it would send the amp into clip because the speaker will demand more power.

 

i honestly didt know this and dont know if any of you lot will go with this.many thanks

[EdBray 0]

Hello my amp will run at 8ohm bridged at 900watt and 1200watt peak

 

i miss read the specs for the sub lol

 

here we go then propa this time

 

THE RCF L18S800 18" WOOFER HANDLES 700 WATTS RMS, 1,400 WATTS PROGRAM & 6,000 WATTS PEAK POWER HANDLING

DETAILED STRONG BASS TONE WITH HIGH POWER HANDLING

THE RCF L18S800 18" SPEAKER IS OPTIMIZED FOR SOUND REINFORCEMENT SPEAKERS, BASS GUITAR, CLUB MUSIC SYSTEMS & ALL HIGH QUALITY BASS APPLICATIONS

I will be running this off a behringer 1280s powered amp in bridge mode along with a amp plugged into the main L&R on the powered amp to 2 top speakers.

 

Do you think i should get this idea outta my head and go for the good old seprate amps,eqs,crossovers ect ect

 

Okay, I'm confused (easily achieved I know) but how are you planning on running your sub?

 

It is usually recommended that you have an amplifier with an RMS of between 1.2 and 1.5 the RMS value required in the same impedance (ohms) of the speakers for mid/tops and between 1.5 and 2.0 the RMS value required in the same impedance for subs.

 

This means that if you have 300 watt RMS mid/tops at 8ohm then you really need an amplifier that will give you between 360watts RMS and 450watts RMS at 8 ohm.

 

If you have a 700 watt RMS 8 ohm sub then you really need an amplifier that will deliver between 1050W RMS and 1400W RMS at 8 ohm. The behringer in bridged mode will supply this, but you will have to use another amplifier to power your mid/tops.

 

Also, the signal coming out of the Behringer will be a full range signal, so I cannot see you being able to use it to power your sub as you would need to remove all frequencies above a minimum of 1000hz and possibly much less for a decent sound.

 

I would use the behringer to power your mid/tops and get another amp and x-over to power your sub.

 

Next, the speaker that you have mentioned is not a complete cabinet, but just a speaker unit. Do you have experience of building bass cabinets? it is not an easy task to make them optimally without a lot of knowledge about the specific speaker and how it performs.

 

[MobileDamo 0]

well done now were talking my business this is what i want to hear

 

i was on the fone with my friend who is very experiance in sound systems as he is a showman using big systems for his fair rides at big fairs he said the same thing as this,also he said that he dont think i would need to have 8ohm and 4ohm will probley be enough untill i upgrte,

 

also he said please corrent me if am wrong that my behringer 1280s will give me 450rms at 4ohms but a 300rms at 4ohm speaker will work perfectly and he also said that a 400rms speaker would work good aswell,

 

so me being me i questiond him as i fought u need the same power for both he said your amp will kick out the mids and ect ect but when you come to the bass in music the amp will clip as it dont have enough power to give the demanding speaker.

 

also he reckons that 4ohms will be enough for like upto 8hour gigs then anything after that it will be the 8ohm plus department

 

i am really starting to understand all this now,no wonder my friend has a amp rack as tall as me lol

[old soul 0]

If I were you, to avoid making a costly error, I would talk to a reputable dealer and explain what you want to achieve. From what you're saying, though I profess to be a little lost, you are looking to buy a set of bass speakers and an amp to run them.

 

In order to do this, as stated above you are also going to need a crossover to split the signal you are sending to your bassbins, and your mid/high speakers.

 

The other alternative would be to buy a pair of bass speakers with a passive crossover built into them, and an amp to run your whole system.

 

Or, I might be completely wrong with what you are trying to do. If so, tell us what you have, and what you want to end up with.

 

Might be worth reading through this post as well, which will give you the lowdown on OHMS Guide to ohms and speakers

Edited January 29, 2008 by old soul

[Andy Westcott 0]

Quote:

"Im thinking your running the risk of frying your amplifier, amps are meant to be between 1 and 1.5 times the power of the speaker."

 

(Puts head in hands...)

 

No it won't fry.

You could run a 10 watt amp on a 2,000 watt speaker and the amp won't notice any difference from running on a 10 watt speaker.

 

I don't know where these myths come from...

 

Anyhow - for loads of thumping bass over a largish area you really need more than 1 single bass bin.

 

What Marc uses - 2 cabs each with 2 X 18 inch speakers in, is far more capable of providing the sort of output you require, and unfortunately this doesn't come cheap.

[MobileDamo 0]

thanks andy i new something was wrong when somone told me i couldt run a set of peavey pro15 speakers from a behringer 1280s powered mixer,my friend told me today on the that the amp will power the speakers just fine,

 

he also sed because am going to use an 15inch speaker i would need the extra juice for the bass which i now believe its true,many thanks.

[NRG Roadshow 0]

Might run it......but not properly......

 

Amps are meant to be 1 and 1.5 times the power to run the speakers properly......

 

You know that as well as I do Andy so why try and make me out as a know nothing?

Edited January 30, 2008 by NRG Roadshow

[Dukesy 0]

Original poster satisfied. Problem solved - thread closed.