3 speakers 2 outputs....help!

[Jaz]

this isnt so much a repost, but on a similar topic as my previous thread

so i am shouting out to all the speaker and amp experts on the site

i have two 120w speakers and a 2x175w amp, but i am now thinking about getting a 15" 200w sub, my dilemma is how to connect the sub to the amp...

AMP: http://www.djcity.com.au/products/spl-5 ... _1526.html

SUB: http://www.kam.co.uk/index.php?action=p ... uct_id=293

it says input via 1/4 inch jacks, what are my options...?

thanks in advanced

[Jaz]

Update:The sub should have your standard lead outputs as well as the 1/4 inch jacks....yeh?

No posts as of yet , but would this work, (:WARNING: do not strain your eye's, very technical!)

speakers running as if normal, positive sub lead into positive B, negative sub lead into negative A, so that the sub would steal some wattage from each channel rather then running the speakers off 1 channel and sub off the other

[Cupe]

erm, i'm not a tech head but i wouldn't wire shit to the same outputs?

you need SourceRaver in on this one. and it's Friday night m8 lol, you're lucky anyone's posting

[Jaz]

i know but in excitment ive allready bought the sub, it was just a deal i could pass up, but im sure someone will give help

this forums been good to me lol

[Cupe]

yea you'll get a full answer by tomorrow, like i said friday night mang.

might be lucky if a techy logs on soon but

[SourceRaver]

Mmmm...

Looks like you can connect your speakers or a sub (in 'bridge' mode).

In most cases you would need a crossover (ie only sends the lower frequencies of sound to the sub for reproduction) for the sub as well.

I'm thinking you will need another amp (and crossover) for the sub.

[Jaz]

sorry but what is bridge mode

the sub specs say "passive built in crossover" does that help at all?

[SourceRaver]

"A stereo amp say has 200 watts per channel (in stereo mode) but in bridged mode, you can double the power to one channel. Say 400 watts in bridged (mono) mode.

You would hit a selector switch that says Bridge and plug your positive speaker wire to the positive speaker of the left channel and the negative speaker wire into the positive of the right channel. You normally can only do this with 8 ohms speakers, and is dangerous for alot of amps to use 4 ohms and bridge them because the impedance gets too low. So please read the owners manual on what type of speakers you can bridge. It normally says also on the amp itself what is a safe speaker to use when bridging"

[SourceRaver]

Built in crossover is good...but you will most likely need a dedicated amp for the sub. You cant bridge a sub and also connect two other speakers.

Also...

Running that amp at 4 ohms is probably not a good idea as it stresses tha amp and I hazard to say this thing isnt the best built amp on the market.

A good rule of thumb when buying amps is to pay a dollar a watt. A reasonable amp whith these specs would cost arround $500.

[Jaz]

Ok will read threw the manuals, I don't know much about the ohms but I think all 3 speakers are 8ohms, hope the amp can take it, don't really have any money for a second amp lol

[Jaz]

would i be able to run the 2 speakers off channel A and the sub off channell B?

[pill]

Yep. Do that, but don't expect fantastic volume. You'd really need another amp for the sub, we can't emphasise how much extra power a sub needs. You will probably blow up the amp as per the wiring diagram above.

THe built in passive xover means you don't need to worry about an active crossover for the sub. Saves you $150, until it blows

Also, you'll probably need a banana plug or bare wire to TRS cable if the sub uses TRS jacks.

[andythemusician]

You'll need another amp and a crossover to do it properly.

I don't recommend firing it all off the same amp - expect shit sound, and if you push the amp, you will be likely to start cooking voice coils.

[Jaz]

Ok well how about that amp for the sub or subs if I get a second, because it wattage is more then my speakers but only just less then my sub, and I will try and get a new amp for the speakers?

That would be the better option yeh? Just hope 175w on a 200w sub will b enough

[FabDJ]

My powered sub has 500Wrms amp and its speaker chews up all its power. Full bore on sub and main amp on 1-3 and its still not balanced (ie no bone shaking bass)

Bass need heaps of power.

[Jaz]

so you think the 175 wont be loud enough for the sub/subs?

am looking at this amp at the moment, thoughts?

http://tpro.com/prods.php?prod=LX-1100

[andythemusician]

I can guarantee 175 won't be loud enough for your sub.

If you are mainly doing light dance music or voice, we recommend that the amplifier power be 1.6 times the Continuous Power rating per channel. If you are doing heavy metal/grunge, try 2.5 times the Continuous Power rating per channel.

http://www.crownaudio.com/amp_htm/amp_i ... _power.htm

What kind of gigs are you playing? Because even if you get an amp to suit one or even two 200w subs, you're not going to be able to play to a big room.

My tops are combined 400w apiece, and I would be pushing to get a good sound with more than 100 people (depending on the room and acoustics of course). When I get subs, they will be in the 500w - 1000w range to help me handle more.

I can't tell you how your sub(s) are going to perform, because the website doesn't give an SPL measurement, but I could bet my right testicle that it isn't going to be amazing. I'd probably use these at house parties and nothing else.

I don't mean to knock your choice or whatever, I'm just trying to illustrate problems you will have should you go down this path, so you can make an informed decision.

If the reason for not buying bigger better equipment is "i don't have the money", then I suggest either hire in the meantime or go without, until you can afford it. Better to buy good once, than buy unreliable crap 3 times.

[Jaz]

gigs will be house party's only for a while, playing pop and house music

that is my main reason yes, i cant afford pioneer etc, just trying to get the best i can on a small budget lol

[FabDJ]

Another alternative is to do garage parties and find a friend who has a massive subs in his ride.

Plug into his mp3 input. Bonus light show with hazard flashers and smoke machine (diesel fuel, petrol engine)