Want to add a subwoofer/bassbin to existing setup..

[plainman007]

Hi Guys,

I have a current audio setup involving two JBL EON 15 type speakers (each rated @ 300 rms) hooked up to a crown amp XLS 202 which is about 250 rms per channel stereo ? And the signal from the source is thru RCA going into the Yamaha Mixer and the Mixers final outjacks going into the Crown Amp.

My audiences are around 200 people max and a quiet seated & listening audience as this is like a conference ambience.

Now in order to add some bass to the sound i thought ill use a subwoofer. I dont need heart thumping bass like at a disco. But some decent thump should do.

1. What wattage of subwoofer should i opt for ?
2. What size 15" or 18" ?
3. Active or Passive ?
4. And how do i fit it into my existing setup ? Will i need another amp or something ?

Looking forward to hearing your ideas.

Thanks...

[Excalibur]

You actually have a multitude of options. In your case, I'd say one active sub, even 12" would do what you want, as would 15" . Certainly not 18".
Power? Well theoretically for a disco, you should have around 1Kw. You won't need that, I'd say 500w would be fine.

If you get an active sub, no second amp or crossover needed, so that's easier. Your second choice is either to run the JBL's full range, and simply add the sub to them, or feed the JBL's hi only from the sub. That's a personal choice. ( The technical term is " Suck it and see" :D :D )

And the last thing will be which cables, and where to put them. :D We'll leave that till somebody suggests a sub for you.

[Pe7e]

2. What size 15" or 18" ?
Active or Passive ?
And how do i fit it into my existing setup ? Will i need another amp or something ?

Looking forward to hearing your ideas.

Thanks...

I'd recommend a single 15" active sub, but which one depends on your budget, I have 4 x 1501 Mackies and love them, others have different preferences. Regarding your existing set up, your Crown amp is well underpowered for the speakers you are using, you could well get an improvement by changing this for a more suitable model, a XLS 402 would suit your set up better.

[plainman007]

Yes ive been wondering if i made a mistake on the crown amp thing. If the speakers are 300w each then is it advisable to have an amp thats slightly higher in RMS per channel ? Lets say 400 rms per channel ? Please demystify this for me.

Cool so i can go for a 15" sub. Ok i will try to find a powered sub to cut the complications maybe. But how do i get the signal out from my source. Where do i grab the signal from and how do i feed it to the sub please ?

[Excalibur]

Yes ive been wondering if i made a mistake on the crown amp thing. If the speakers are 300w each then is it advisable to have an amp thats slightly higher in RMS per channel ? Lets say 400 rms per channel ? Please demystify this for me.

Cool so i can go for a 15" sub. Ok i will try to find a powered sub to cut the complications maybe. But how do i get the signal out from my source. Where do i grab the signal from and how do i feed it to the sub please ?

Ah yes, the easy questions. :D Most of us now run with an amp around one and a half times the RMS rating of the cabs. As to demystify, sorry I can't, but start at post #6 on here. It may help.
http://www.mobilediscodirectory.co.uk/forums/showthread.php?t=10463

Two choices next. Purely personal, cos there are folk on here which do both. I do either from time to time, so there's no hard and fast rules.

1) Mixer out into sub, tops fed from hi out on sub, getting only high frequencies, thus working efficiently. Textbook operation.

2) Mixer out into sub, tops fed from thru output. Tops get full range, and cos they're 15" they're fine. Sub just adds more bottom end.

Like I said, suck it and see.

[Pe7e]

Cool so i can go for a 15" sub. Ok i will try to find a powered sub to cut the complications maybe. But how do i get the signal out from my source. Where do i grab the signal from and how do i feed it to the sub please ?

You take both outputs from your mixer to the sub input, and since you are using full range speakers you can take either the two full range 'through signals' or the two 'Hi Pass' signals from the sub to your amp inputs, the former will give you a more bass.

[plainman007]

Does this mean all subs have several outs on them ??? They have a set of out for hi-passed audio and a set of outs for Fullrange out ? Or am i misunderstanding this ?

Thanks

[Excalibur]

Does this mean all subs have several outs on them ??? They have a set of out for hi-passed audio and a set of outs for Fullrange out ? Or am i misunderstanding this ?

Thanks

Usually yes, though maybe not all have this feature.

[plainman007]

My speakers have a set of 2 speakon inputs on the rear of each speaker. Does this mean its takes the signal into one and sends the same signal unadulterated out of the next socket ?

[Pe7e]

My speakers have a set of 2 speakon inputs on the rear of each speaker. Does this mean its takes the signal into one and sends the same signal unadulterated out of the next socket ?

Almost certainly yes, if you connect another speaker up to the second speakon socket it will 'share' the feed but will also increase the load on your amp, use with caution.

[Excalibur]

My speakers have a set of 2 speakon inputs on the rear of each speaker. Does this mean its takes the signal into one and sends the same signal unadulterated out of the next socket ?

Yes, probably, but you're not going to use that for anything. :confused: And for :Censored: sake, DON'T connect that to a powered speaker.

[plainman007]

Thanks for the answers. Very helpful.

My speakers are said to have a 300w rms handing capacity. But is there a technical way of finding out what the actual RMS is ? Or do we just have to go by quoted figures ?

So its always safe to get an amp 1.5 times the wattage of the speaker is it ? Hence a 300 + 300 Rms Stereo setup requires a 450 + 450 Rms Stereo Amp ...Correct ?

[plainman007]

Excalibur > Sorry i saw your post only after i posted my previous one. So the signal coming out the second connector (which for PETE's sake i shouldnt connect to a powered speaker) is an amplified signal meant for a passive speaker. If my amp was 300 rms per channel and i had 6 x 75 Rms speakers then i would be safe hooking 3 for left and 3 for right, in a daisy chain fashion using these outputs from each speaker to feed the next speaker...am i understanding correctly. Please pardon my naive clarifications. Im learning and intending to learn properly :).

[Pe7e]

If my amp was 300 rms per channel and i had 6 x 75 Rms speakers then i would be safe hooking 3 for left and 3 for right, in a daisy chain fashion using these outputs from each speaker to feed the next speaker...am i understanding correctly. Please pardon my naive clarifications. Im learning and intending to learn properly :).

Not necessarily, you need to be careful here, if you daisy chain speakers you alter the load the amp 'sees', ie 3 x 4 ohm speakers connected in series will give a loading of less than 2 ohm, many amps will not handle this load.
More info HERE (http://www.ehow.com/how_2041753_determine-total-speaker-load.html)

[plainman007]

If i do get an XLS 402 in the future to better suit my left n right speakers rated @ 300rms each, Will my existing XLS 202 go to a waste ? Or is there someway i can use it in the setup ? Can i run it in bridge mono and use it to drive just passive sub ? Subs dont need a stereo signal right ?

[Pe7e]

If i do get an XLS 402 in the future to better suit my left n right speakers rated @ 300rms each, Will my existing XLS 202 go to a waste ? Or is there someway i can use it in the setup ? Can i run it in bridge mono and use it to drive just passive sub ? Subs dont need a stereo signal right ?

You could use it to drive a single sub, I believe it provides 600w @ 8 ohm in bridge mode.

[plainman007]

how do i make it work in bridge mono mode. Or lets say to test it out at the moment. Since its underpowered for my 2 speakers which are 300rms each. Can i try running my amp in bridge mono to feed the same 2 speakers so that the amp does not strain ?

[Excalibur]

If it were me, and funds allowed, I'd buy two passive subs, a Crown 402, and an active crossover. That way, if you wanted to use the tops on their own, you'd have a bigger amp to drive them, and a spare.

For the bigger gigs, keep the 202 on the tops, 402 on subs, and you'll find that suddenly the 202 is big enough, cos you've taken the hard work of the low frequencies out, and given them to the bigger 402.

I haven't read up on the size of the Crown amps, and wouldn't rule out different sized ones, eg 802 on subs might easily be a better match to the tops in a full rig, but a bit big for the tops only. .

[plainman007]

Hi Excalibur,

I simply cant afford buying 2 subs and a crown. At least not for this gig that im doing. For several reasons. I dont think ill need 2 subs for a lecture based event pitched at a silent listening academic audience. And neither does the project warrant spending on that. Plus the size of things would go up so much i will need another vehicle for transport. This will increase my investment. Plus my transport costs will increase and my audience is not going to pay for the quality difference. All the increments seem to be going out with nothing coming to me in return and hence is a bad idea. I would maybe just want to add some bass to the existing set-up and id like to do this at the minimal cost possible.

If i was in the rental industry / disco industry like most of the members here where i will get different gigs where i can recover cost then i qould have invested. But im in a totally different industry alltogether.

But so far no one has suggested any subs / models.

[Steve the DJ]

Whereabouts are you based?

I have (potentially) the ideal solution sitting in the garage...

[plainman007]

Im based out of Srilanka.....other side of the globe probably im guessing.

[Steve the DJ]

Oh...

I can probably get the sub I have to you no problem, but it will cost more than the sub itself... :bang:

[Excalibur]

Plainman, sorry, I forgot the constraints you placed on the original question, and went into "what I would do mode". Oops. :o :o :o

Right, having taken that on board, keep what you've got, just get one active sub, and feed it from the hi out sockets. Hope that Steve (FDDJ, among his aliases :D :D ) has something like that in mind, and is near you. Edit: Wow. :eek: :eek: The power of the internet! Don't think anybody's going to Sri Lanka for their hols.

As for suggestions, sorry, I don't have any personal knowledge of actives, so can't help. I only do passive.

[plainman007]

FDDJ > Yeah i was guessing so. Nowadays shipping something in from USA/Canada/Europe can be much more expensive than picking it up in my own country. But thanks for the offer anyway :).

Excalibur > Lol. Thats ok. It happens. You mean get an active Sub with high outs. Then feed in the signal first into the Sub ? But will my cables match. I have a pair of jacks that plug into the STR out of my mixer and these jacks have their other ends made to match my crown amp input jack. So the question is do subs have the audio input socket the same as crown amps input socket ? Then the second question is , the high pass outs of the sub have what type of socket ?

Thanks

[Pe7e]

FDDJ > Yeah i was guessing so. Nowadays shipping something in from USA/Canada/Europe can be much more expensive than picking it up in my own country. But thanks for the offer anyway :).

Excalibur > Lol. Thats ok. It happens. You mean get an active Sub with high outs. Then feed in the signal first into the Sub ? But will my cables match. I have a pair of jacks that plug into the STR out of my mixer and these jacks have their other ends made to match my crown amp input jack. So the question is do subs have the audio input socket the same as crown amps input socket ? Then the second question is , the high pass outs of the sub have what type of socket ?

Thanks

The active sub will almost certainly have XLR f/male input connects, so you need 2 x XLR male to whatever your mixer outputs are, and 2 x XLR to XLR to connect the sub 'hi-pass' (or through signal) to your Crown amp. Your old speakers connect to the crown amp as usual.

[plainman007]

Thanks. Now i understand it clearly. Problem is in my country, the tech guys are nerds at the stores and also they never have a wide variety of choice like you do in the UK and US etc. So i cant even visit and find out how it works. They just want you to buy it and leave. They wont even tell you or show you how it connects. They will tell you theyre sorry they cant demo it since they dont have this and they dont have that. If you asked to listen to it, they would ask you to come back the next day or after 2 days for it. lol.

So im having to learn from fellow members here like this. :).

I was still wondering if i wanted to use my Crown amp in bridge mono mode how do i do that please ?

Regards

[Pe7e]

So im having to learn from fellow members here like this. :).

I was still wondering if i wanted to use my Crown amp in bridge mono mode how do i do that please ?

Regards

Here's a link to a Mackie active sub user manual (yours may be different) HERE (http://www.mackie.com/pdf/swa1501_om.pdf)

Here's a link to your crown amp's user manual HERE (http://www.crownaudio.com/pdf/amps/139441.pdf)