Tyson12345

Ok, so I went out yesterday and got myself a sub and amp (12" Infinity Kappa and a MTX Thunder TC3001). After getting everything setup, I decided to test it to make sure it's working fine before I start hiding everything and putting the sub into a box.

To my surprise, it almost sounded as if there is no sub at all. So I checked the head unit again and I switched the RCA cables (there's 2 outputs) and it sounded a little better. But even then, it feels as if there's no power.

Is there something else I can do? Or will it be a lot better if I put it in a box? I went out this morning to double check everything and everything seems fine, I even cranked the bass on the amp. When I turn the music up, the sub barely moves at all. You don't notice it unless you have your head right beside it.

Please help me out.

John__Taylor

iTrader: (3)

1)Provide a link to your Sony deck. It sounds like maybe it has no sub pre outs on it. Some decks have a switchable pair of rear outs, you can set the rear prouts for non fading sub use, or regular rear door speakers.

2) Are the gain controls on the MTX turned up at all? Put the m at halfway to start with.

3) You can wreck the sub by playing it in free air, but it should still sound louder than what you are describing.

4) You have power and ground at the amp right?

It almost sounds like the MTX is being bypassed somehow and the headunit is trying to drive a big sub with 12 wrms or something, in which case the sub would barely move like you are describing.

Tyson12345

I think it could also be a case of not having a strong enough amp for the sub. I will be heading out probably this week to take back the amp and get a better one more matched for the sub.

Either way though, my deck is a Sony GT410U: http://www.sony.co.uk/product/ica-cd-tuners/cdx-gt410u

Thank you.

John__Taylor

iTrader: (3)

It says "Rear sub switchable" so before you spend time taking the amp back, try going into the setup screens on the deck and changing those rear outputs to "SUB".

You did not mention what your sub was, but I think once you switch over those preouts in the decks menu, you might be surprised.

EDIT: Oh, the Kappa. 122.7? They are good for 350 wrms (+) if thats what it is.

Tyson12345

Yeah that's the sub. But it also runs at either 1 or 4 OHMs. My amp is only 2 or 4. 4 only gives out 150 Watts where as the 2 gives out 300 Watts. Is it alright to switch it over to 2? Or would this ruin the sub (or amp)?

Since both are low in power, I'll be getting something that can actually use the sub for what it's worth. I'm thinking a TC4002 which can give out 900 Watts at 4 OHMs.

I'll go check those settings right now.

John__Taylor

iTrader: (3)

I have the same subs, I can tell you they do like power. You must leave it set at 4 with that amp, but if you bought another sub, wired it up together with the first one, then the amp would "see" a 2 ohm load, however 150 per side is not enough in any case.

TC4002 is a 2 channel amp isnt it? Why not go for a class D monoblock sub amp? I am using an Alpine PDX 1.1000 which is rated at 1197 to drive 2 of those subs, of course you cant go insane with the gain control or you will kill the subs.

Most of the good monoblocks have 2 connections with internal bridging, so you would leave the subs set at 4 ohm, hook up one to each connection, and the amp would drop it down to 2 ohm. (if you had 2 for example)

Tyson12345

Where do you go to buy your gear (if you don't mind me asking)?

Also I don't have the biggest budget to work with. I only work part time in the reserves and until I start going to basic, I don't get a lot of cash. Like right now, I'm trying to sell my xbox so I can afford an upgrade to a bigger amp.

I was looking at Hifonics amps at some online wholesale site, but I got iffy when I read the shipping rules about getting products to Canada with the whole tariff fees and all.

John__Taylor

iTrader: (3)

Pretty much anywhere. Some new, some used, some right here from people on the forum.

There are a lot of vendors on this site, near the bottom for sale section.

You can get burned on shipping/tax/duty, etc from the States, but 2 general rules to follow..try to get "made in the U.S." stuff (free trade, no duty, etc) OR try and get it shipped by prepaid air. Brokerage fees are usually paid in advance that way.

There is a vendor here named PORTIMEX, he sells Elemental Design amps from Montreal. I think his latest ad is "boxing day in October" you could get a decent monoblock off him for much less than futureshop.

Did you find the settings on the deck?

Tyson12345

I checked out the deck and everything seems to be fine. I can also control the sub from the deck so I figured everything is working correctly. Still not much going to it though, so I'll definitely have to get something new.

When these subs are getting the right amount of power to them (lets say 1 sub for now), will it thump really good? Or should I look into taking that back too and getting something different altogether?

John__Taylor

iTrader: (3)

I'm very happy with mine. They have gotten better as they become more broken in as well. I have them in a dual (now sealed) ported Bassworx enclosure, 3/4" MDF except for the baffle which is 1". My box has been sound deadened completely inside, and then about a pound of fiberfill in each chamber to boot. Mine sound very precise. Loud too.

I dont know what I'm putting to them (600, 700, etc) because the gain is less than half on the Alpine.

These subs were darn close to $300.00 each at one point, then FS (mistake?) put them up for $99.00 each, I should have bought 4. Then they went to $249.00, now I think they are on for $149.99, and FS still wants $209.00 for the 10" one I think.

Anyway, very, very, stiff cone material on them. Woven glass fiber or something like that. Different sound than say a sub with an aluminum cone.