Buying a sub, got a few questions first...
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Posted on Jan 01, 2009 11:45 am
JackWhite
Member Since: Jan 01, 2009
As the topic says, I'm buying a sub (on a tight budget) and I'm looking at the Intimidation The Intimidator. Now this is a passive sub and I already have 4x Intimidation INT-112X's (2 of which may be sold once repaired).
1) Will my amp be able to handle the sub and 2 of the speakers (possibly 4?)
2) What would be the expected selling price for 2 INT-112X's with replaced tweeters (they blew).
3) If I do need a new amp, what's the best way to go? 2 amps with a crossover or just 'daisy chain' it?
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Noize2uCzar of MidiAdministrator
Since: Apr 04, 2002
Jan 01, 2009 02:50 pm I guess I'll ask what amp first off?
You can check a few of these links to see what they might be going for. www.google.com/search?hl=...2+X&spell=1
A separate sub amp is always a good way to go, a crossover is a must have for using a sub.
Maybe Rob will stop by and catch this one. He is an FOH guy and has much more experience with the live sound side of things. He can help you get a bit more detail for what you can and can't do with this set up.
Jan 01, 2009 04:51 pm The amp is a Kam KXR 300 watt amp, forgot to mention that!
The problem is, I'm very new to PA systems and I'm not too sure what's the best thing to do. I've seen the back of some amps and I don't have a clue what to do (mine's simple :))
Is it ok to have an input from one channel on my amp into a sub then into a speaker, and have the other speaker just straight from the amp? And could I run 2 subs and 2 speakers in the same fashion, or would it draw too much power?
Noize2uCzar of MidiAdministrator
Since: Apr 04, 2002
Jan 01, 2009 07:22 pm Oh ya, that would draw too much for that amp using the speakers you mentioned above. That amp is barely enough to power a pair of the 112X speakers you mentioned above. I am not sure what subs you would be looking into, but most are pretty power hungry and require an amp all on their own.
But like I said, I'm not a real expert on this so I'll leave the real tech stuff to Rob when he gets here.
Jan 01, 2009 11:06 pm Hey Jack. Sorry to say that what Noize is telling you is correct.
Your amp is very light for the speakers that you have. And this could have caused the problem with your tweeters already.
When ever you have an amp that is below the rating of your speakers, you can run into a dangerous situation of what is known as square waves.
Square waves are caused by the speakers not clipping, but the amp is. When an amp clips, This means that the output transistors have reached the max voltage swing that they can produce. When this happens, the voltage flat lines for a period of time. This flat line, tells the speaker to move out as far as it can. Then to stay there, then move back in. The stay there part is where the damage happens. This creates heat. Heat is the death of all electronic components. Causing things to distort, and tear themselves apart.
By putting two of the speakers on the side of the amp that you have. They have a total ohm load of 4 ohms, and can absorb 800 watts. You add the wattage together for how much you are going to need.
So, you can see that an amp that outputs 300 watts to speakers that need 800. This is a problem.
So, you will need a larger amp, and a crossover as noize stated, plus an additional amp for the subs.
Going above the wattage that you need is 100% OK. The speakers will let you know that they have had enough. You will hear distortion coming out of them. But, this is also doing damage, so be careful not to allow this to happen to much.
Going with an amp that can produce 1000 watts, is what you should look at. For your subs, they can handle 600 watts each. For two of them, you need an amp that outputs around 1500 watts.
Jan 01, 2009 11:41 pm Oh dear, the amp and speakers (not 4 but 2) were sold as a package, and new to the game I assumed they were well matched.
Problem is that I really don't think I'll be able to afford two more amps on top of speakers, but equally I don't want to shell out on speakers that will break my (currently) fine amp.
I'd be looking at around £500 for the 2 amps at the least, plus another £200 for the subs. Not sure where I'm gonna get £700 from!!!
Any cost effective solutions or is this my only option?
EDIT: Forgot to mention the cost of a crossover, though not sure what I'm looking at with them so I don't know about prices.
Jan 01, 2009 11:44 pm Suppose I could always pay by finance, but I'd rather pay the money outright, so I know I'm getting what I can afford.
I suppose another option is to stick with what I've got. Shame adding more bass comes with such a huge price tag!!!
Jan 01, 2009 11:48 pm That sucks that someone did that to you. You would think if they are sold together, then they should match.
But, this is the sad reality of our industry. The price tag that is attached to the equipment. Thank God for Ebay. From time to time you can find a great deal on there.
I do some research on there for you. See if I can find a good amp at a great deal. Also, I'll see if I can find a good crossover for you. I'll get into what, and why you need one shortly.
Jan 02, 2009 12:02 am It is out of my range at the minute, but I should be making some money soon. I'm a University student in the UK at the minute, so money is hard to come by. Ebaying a load of stuff including an edirol midi keyboard and an ion icue soon though, so I should be saving some pennies.
Jan 02, 2009 12:05 am They're about £3-400 to UK buyers. Would a regular stereo amp be alright for the subs?
Jan 02, 2009 12:15 am Depends on what you mean by "Regular"?
Jan 02, 2009 12:18 am As in I'm guessing I don't need a "subwoofer specific" amp?
I've not seen one yet so I assumed they don't exist?
Jan 02, 2009 01:13 am Oh, I'm sorry. We are just referring to what the amp is running when we say sub amp.
So, yes. A regular amp of the wattage required, will work.
Jan 02, 2009 08:03 am Would an active sub solve my problems?
Jan 02, 2009 11:46 am A self powered. Yes and no. Yes, you would not need a crossover at that point.
No, you would not be able to time align the sub in your system.
Jan 03, 2009 06:47 pm How do you mean I wouldn't be able to time align it?
Jan 03, 2009 06:56 pm Time alignment is just another important step in live sound. where the driver sit in relation to one another determines what resident frequency will be heard.
For just an experiment, take two of your top boxes. Place on directly on top of the other. Play some pink noise through both. Then slide the very top box back slowly. Listen to what happens to the sound when you do. You should hear the sound change in relation to how fast or slow you move that top box.
The same thing happens on a gig when you are placing the subs to the tops. Without an electronic device to delay the top boxes to your sub, you get cancellation. That cancellation is what you are hearing when you slide that top box in our experiment.
A crossover has delay in it. that way you can time align all of the drivers together so that there is no cancellation.
Jan 03, 2009 07:23 pm Would it be possible to run them all (passive) off one amp but a very high powered one? Would that be more cost effective?
Jan 03, 2009 07:33 pm No, you need a device in the middle of the chain to separate the frequencies out to the subs and the top boxes. You only want to send the lower frequencies to the subs and the higher to the top boxes. If not, you are sending full range to all boxes. This will make your subs sound like crap. Plus, they will not be able to respond quick enough for a nice punchy bass.
A crossover does all of this. And will allow you to adjust what goes to each of the boxes that you have.
Jan 03, 2009 07:35 pm Ah yes, sorry I meant with a crossover, would it be possible? Or most importantly, cost effective.
Jan 03, 2009 07:41 pm Still sorry to say, no. Once your separate out your frequencies you can not recombined them into one amp. Coming into a crossover, you come in Left and Right. Leaving, you are Left Low, Left High, and Right Low and Right High. So you have four outputs. Which means that you need two stereo amps.
Jan 03, 2009 07:47 pm Oh I see now, I though that the crossover came after the amp. Fair enough.
Jan 03, 2009 07:52 pm Hey Jack, What's your email? I have a document that may help you with some of the basics of this.
Jan 03, 2009 07:58 pm When you say I'd need a 1kw amp, do you mean 1kw total or 1kw per channel?
Jan 03, 2009 07:59 pm it's on it's way.
Jan 03, 2009 08:10 pm Thanks for the document, hopefully I should be set now, thanks for all your help! Greatly appreciated!
