GS4_Fiend

iTrader: (22)

the technicians that I talked to all said if i parallel it, it would become 2 ohms and if it was series than it would be 8 ohms?? Or did you forget it is Dual Voice Coils 4 ohms each coil?

You guys with subwoofers out there like to put it @ 2 ohms or 4 ohms and why?

I was planning to go with the Rockford P300-1 mono amp. 300w x 1 @ 2 ohms.

About sound deadening. My friend got a 2000 honda accord coupe. He got a pair of rockford fosgate 6 1/2" coaxials POWER series rate at 75 W RMS. Amped it with a kenwood amp at 100 w RMS. And he doesnt have a single dynamatt on it and it still sounds good. Weird. It doesn't vibrate that much either. His setting on the frequency for the speakers are at 150 Hz. What you think?

Big Mack

iTrader: (1)

And they'd be correct.

He was basing his answer off your original number of 4 ohms in series. This would imply dual 2 Ω coils.

It's usually not about "like," it's usually about what works with the amps being used in most cases. I prefer to run my amps cooler, so I try to stay away from super low loads. When you combine a low load with an even lower damping factor (AKA "control" of the woofer), it makes sense not to run them low, but I understand the capability factor, too.

A good choice for your application.

I think your friend is not running any bass through his speakers, therefore he's not going to get a whole lot of rattles. The resonant frequency of those speakers (where the cone vibrates the most) is about 54-60 Hz. At 150, he's almost an octave above where that can occur, and since 150 is probably not a harmonic of the Fr (Resonant Frequency), it won't even rattle the frame of the speaker a whole lot.

Big Mack

Lanson

Dude, the website you referenced has misinformation. It has dual 2ohm coils listed in its T/S specs, but listed dual 4ohm in its sales specs. Bottom line, I was using a single sub with a dual 2ohm v.c.

There is no need to consult a "technician" on these matters, it is simple physics. If the sub reads as a dual 2ohm, you can run ONE sub in either 1ohm or 4ohm load. If the sub reads as a dual 4ohm, you can run ONE sub in either 2ohm or 8ohm load.

All other things being equal, a higher impedance provides a better damping factor and thus better cone control of the sub. If you are going for all-out power, you use 1ohm typically because serious power amps are monoblock 1ohm or better. However, for a simple (dare I say weak?) 300W RMS sub, a simple amp will match to it quite well. I had you confused with your situation with Ryan78, because of the heavy tangent away from processors and more into subs and amps. You couldn't make me buy and use an RF amp because there is so much more available out there that do better, but if you already have it then by all means the P300-1 will serve you well at 2ohms. Just validate the sub you have is of course a 4ohm dvc sub, not like the one that was shown in the dcca ad.

With regard to deadening...your friend doesn't have a system, he's got a couple of coaxials. You could still improve the sound quality tremendously for him by installing proper CLD tiles (that's Dynamat to the unwashed), CCF, and MLV in the right places with attention to detail. Metal vibrates, it makes its own harmonics to the music you are playing, and effects the sound quality. Also rattles and buzzes are annoying. Big Mack could not possibly be more correct on this topic as well.

For reference on what would be considered a decent system for most beginning or moderate car audio enthusiasts:

A set of 1" soft-dome tweeters, runs highpass at about 3kHz and up. Amplified with about 25W per channel
A set of 6.5" woofers should run band-pass, from about 75Hz through 3kHz. Amplified with about 50W per channel.
A single 12" subwoofer should low-pass from about 75Hz and down. Amplified with at least 300W, 500W would be more ideal for headroom purposes.
A decent processor or processing-head unit that can delegate which signals go to which speakers, and also time-align the signal for proper staging in the driver's seat.
Solid deadening practices

As simple as that is, whenever you cross your mids high up at ~105Hz, you are leaving a LOT of midbass on the table and the overall soundstage will sound thin and lifefess. Midbass is the key to getting a fuller sound system, and to do midbass correctly, you need cone area, a well-damped and sealed door, amplification around 50W or better per channel (this is a guide, not an absolute!), and importantly you need attention to detail in the install regarding things like gasketing off the speaker from the door, etc.

GS4_Fiend

iTrader: (22)

Omg. This is tutorial! Thanks so much!

I gotta figure how to get my front speakers to sound good @ 75 - 90 hz on high pass. I am lacking in the midbass.

Big Mack

iTrader: (1)

Is your crossover setting still at 125 Hz, or did you lower it down like I said to? If you're lacking midbass, this is the "hole" I was speaking with you about! Remember what I said - you'll be down about 24 dB between 80 and 90 Hz when you figure that your 12 dB down point is 1/3 of an octave from where they are set. It's a science, mang, and you don't mess with science!

Big Mack

GS4_Fiend

iTrader: (22)

Yesssir! I did remembered your advice. It didn't sound clean because the bass sounds horrible like muffled (don't know the right term). Like I posted, I would need to install the clean sweep to clean out that stock headunit's signal and I will update ya! Thanks

Lanson

Few things here. Deadening (as I previously discussed Ad nauseam) and sealing of the door will yield a much more potent midbass range. As will attention to detail like gasketing off the speaker from the door. Damn this sounds familiar...

A decent 6.5" driver will dig down to around 70hz or so quite easily provided the above-mentioned work has been done, and provided the x-max of the driver is sufficient.

BTW I wrote some awesome stuff but the CL Forums were unstable and I lost it. It probably wasn't important anyway since you've got a lot of work to do on the install-side first, but maybe we can cover some things later on after that.

Lanson

This muffling is also attributed to the deadening / sealing / A.T.D. issues.

GS4_Fiend

iTrader: (22)

I think I need to buy those cups that goes in the back of the speakers

Lanson

Why do you think this?

I have never used them, btw. If that gives you an impression of how important they are. They are acoustically transparent or at least claimed to be; they are not an enclosure.

If they WERE an enclosure, you would not want to typically use them because a speaker needs airspace to work in most situations. Some speakers work better in a sealed environment, some ported (tuned), some infinite baffle (IB). That last one is more common than any other when it comes to car doors, because car doors indeed behave IB if they are properly sealed and deadened.

The only viable reason to consider those cups is for one thing, and that is to keep the speaker from getting wet in what I consider "wet" doors. Some door designs are horrible at keeping water away from the speaker, and a constant deluge of water on a paper speaker can make for a nasty surprise one day. Otherwise, this is a non-issue. I assure you, the Lexus lineup does not have "wet" doors!

GS4_Fiend

iTrader: (22)

What should I do then? All I got is dynamat around it and that's it

Big Mack

iTrader: (1)

Dynamat the entire door, making sure that your speaker mates up with the surface it is mounted to. If there are any gaps around it, it's not going to separate the front wave from the back wave, meaning little/no bass. Keep in mind that you're not running an extraneous amount of power, either. Sealing up the doors with the dynamat will help.

And I agree with fourth - the XTC baffles are not enclosures. They can, however, assist with the midbass portion of the music - of this I can attest based on personal experience. In doors that are VERY open, meaning nearly no interior skin or skin that rivals Swiss cheese, the baffles do assist a bit. Other than that, I don't think you'll need them. Even when used to prevent water, you are better served to cut a large hole in the bottom of the baffles to prevent them from enclosing the speaker too much, since most speakers are designed to run in open door area.

Big Mack

GS4_Fiend

iTrader: (22)

Dynamat the whole door.... whoa.. I guess that's the only way haha. Ok. I found out the CL444DSP was not the only unit, I also needed the CL-SSI for summing for full range for my system to work properly. Question, since the cleansweep will be taking control in the volume. Where should I put my volume control at?

Lanson

Stop I didn't say the whole door.

www.sounddeadenershowdown.com teaches you exactly how to do it using the least materials, weight, and cost necessary to get the biggest improvement in sound.

And remember, I have no knowledge of the cleansweep so I'll leave that to others in the group.

GS4_Fiend

iTrader: (22)

I did dynamat around the speakers. But I will take action on that website. Thanks.