SQ still not up to par.

[cheebah 10+ year member]

Hey guys,

You might remember a post I made a while back about some old p2's not sounding very good at all at mid volume. Well after resistance testing the voice coils I found that they were a little below spec, I had them wired for 4 ohm and was seeing 3.4 so I decided to buy a pair of brand new alpine type r, DVC 2ohm subs. Keep in mind that this was after replacing HU, amp and box without a single improvement in SQ. So the new subs came in and I installed them. Much to my dismay the exact same SQ problem I was having with the P2's is occuring with the type r's. Essentially what happens is at mid volume the subs begin to sound horrible, no smoothness and the subs barely shake my mirrors. I know they should be able to handle ear splitting volume. So let me breakdown the current situation:

-Brand new HU, amp, box and subs

-Amp: Kenwood KAC-9105d (900w rms x 2 @ 2ohm)

-Subs: Alpine type r, DVC 2ohm, (600w rms)

-HU: Clarion cz1000, amp pre out = 2v

-Box: Scosche sealed, 1.25 cubic ft

I don't need any critics like last time so let me give you some background. I was a navy electrician and have done systems before. This system IS installed correctly with proper splicing/terminal hardware. The amp input sensitivity is matched with HU amp pre out. The bass boost is at %50. Voltage at amp and battery reads 12.23 when car is not running and 14.38 when at idle. With the music turned up to the point where I am having the SQ issue there is only a drop of .4v (at amp and battery) even after the loudest of bass hits.

The only potential issues I can think of is that the speaker wire I am using for my subs is only about 18g or my HU is not adjusted correctly. I've read elsewhere that 14-10g is the standard but I somehow doubt that less than a foot of 18g wire is causing this problem. My HU has a lot of base settings and I have tried many, many combinations of LPF, SW vol, Bass level and frequency to no avail. Please, any ideas would be greatly appreciated.

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[RAM_Designs 5,000+ posts]

3.4ohm is perfectly normal for a "4ohm woofer." And turn the bass boost off on your amp.

 

[09civic 5,000+ posts]

And turn the bass boost off on your amp.

this

 

[cheebah 10+ year member]

there is no "off" switch. Turning it down means I don't get any bass at all...

 

[Cruzer 10+ year member]

bass boost will make subs sq suffer considerably. not to mention its bad for them in terms of durability.

imo shouldnt set ur gains to what ur hu is supposed to be. do it by ear. push the gain till the output is as much as u can, but with them still sounding good.

u have a prefab box, that may or may not be a problem. i have p2s in a prefab sealed box, they dont sound good either. could be subs, could be box, not in my car so i dont care. u could try and build ur own box. i bought a cheap $20 nail gun, $2 nails, $5 glue, and of course the mdf cut by the local lowes. so simple, worth a shot imo.

lastly, type R, and rockford subs, are not SQ subs. they are get loud, while sounding good.

look at the exodus shiva-x

dayton HF series

Stereo integrity subs that use the xbl2 motor(si mag, si bm mk)

AE AV subs

peerless subs

focal subs

those are true SQ subs

 

[whitedragon551 5,000+ posts]

there is no "off" switch. Turning it down means I don't get any bass at all...

Then your gains arent set properly.

 

[LaserRed38 10+ year member]

As others have said, your first problem is buying subs that sound like crap. Second problem is install. Third problem is tuning. You need to read up on here first, and stop throwing money at the wind. So yes, you do need critics because even though you managed to get the stuff installed, that doesn't mean you know what you're doing. It doesn't matter what you do for a living. If you don't come in here with an open mind, you'll never learn anything. And your speaker wire thickness has no bearing on how a speaker will sound, however you are lucky you haven't started a fire using 18 gauge for a sub. Btw I didn't bother looking up the model #, but I can almost guarantee you Kenwood doesn't make an 1800w amp, and it probably isn't even putting out 900w @2ohm.

Lastly, since you're running sealed, it doesn't matter than you have a prefab box so keep it. Is it 1.25cu for each sub? Or both.

 

[cheebah 10+ year member]

...I promise you I am not "throwing money at the wind". I read these forums thoroughly. Many threads concluded that type r's are the best sub for this price range and that they are second only to JL w7's, which are out of my price range. I did not mean I didn't need constructive critics, what I meant was I didn't need smart ***** and if you read my previous post on this matter you'd see why I mentioned that.

Kenwood KAC-9105d 1800w Amazon.com: Kenwood Kac-9105D 1800-Watt Class D Mono Amplifier: Automotive

I don't have an unlimited supply of money so I'd appreciate it if you didn't down my system and just help get what I can out of what I can afford. These may not be top of line subs but there is no reason why they should sound like this.

The box is 1.25cu per sub, alpine says optimum is .9 and allowable range is .75-1.25

 

[cheebah 10+ year member]

oops time out

 

[Cruzer 10+ year member]

type r isnt the best in its price range, it isnt the next best thing to a w7. its a solid sub for the money, and should not sound like crap.

if optimum is .9, why would u go 1.25? then add 300 watts over its rated rms in a box that is too large? my guess is thats why it sounds bad. if u want to use more wattage than its rated for, u go smaller, not bigger.

for example sundown 8, if u use 400 watts, u can get away with 1 cubic foot, but u wanna use 600, 800 watts, .6, no larger, says the owner of sundown, and designer of the sub.

 

[Cruzer 10+ year member]

type r isnt the best in its price range, it isnt the next best thing to a w7. its a solid sub for the money, and should not sound like crap.

if optimum is .9, why would u go 1.25? then add 300 watts over its rated rms in a box that is too large? my guess is thats why it sounds bad. if u want to use more wattage than its rated for, u go smaller, not bigger.

for example sundown 8, if u use 400 watts, u can get away with 1 cubic foot, but u wanna use 600, 800 watts, .6, no larger, says the owner of sundown, and designer of the sub.

 

[LaserRed38 10+ year member]

1800w...max. 900w RMS @2ohm...rated...which means it probably only does around 750. If you concluded that the majority of threads you read on here say the W7 is king and the Type R is second, I don't know what to say. Just...no.

The Type-R USED to be a nice SQ sub. Around 2003. Then it got cheapened and it is only useful for making noise. In a ported enclosure. Sealed, they sound like fart. I suggest selling your equipment for as much as you can and starting over. Keep your HU and box. Look through the classifieds. Don't be afraid to buy used. How much did you spend on all your equipment and what is your budget. What are you trying to achieve? What kind of music do you listen to?

 

[SmartAsss 10+ year member]

Then your gains arent set properly.

ditto.
Don't think that by lining up the gain knob to 2v will set the gains correctly... the marks are only there for a general idea of what its being set at. also the headunit does not put out 2v unless it is at 100% max volume. your probably looking at closer to 1.5v at 3/4 vol. 1v at half vol. turn the b-boost off you should have plenty of bass without it. the natural cabin gain of your vehicle provides up to 12db+ of boost at 20hz. It starts right around 80hz in almost all vehicles and increases a from there down.

As others have said, your first problem is buying subs that sound like crap.

If you were to take two very different subs, put each one in its own proper enclosure, then adjusted the output sound level to match. it would be extremely difficult if not impossible to tell the two apart. buying a "SQ" sub is just not very important. Installation and settings are the main concern.

 

[Cruzer 10+ year member]

If you were to take two very different subs, put each one in its own proper enclosure, then adjusted the output sound level to match. it would be extremely difficult if not impossible to tell the two apart. buying a "SQ" sub is just not very important. Installation and settings are the main concern.

k u buy ur spl sub ill buy my low distortion, low inductance sub, lets meet up so i can show u sq

 

[LaserRed38 10+ year member]

k u buy ur spl sub ill buy my low distortion, low inductance sub, lets meet up so i can show u sq

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