Phase Plugs, why and how

[OnYrMrk]

I want to use the subwoofer as little as possible. I am just trying to make it all fit. I can buy the SRX2 for about 150, if it is still available, and I can put it on the tweeters, then run the other LRx2's on the mid and midbass drivers.
I just can't hear the midbass, hardly at all, so I want more of a "hard hitting midbass with less audible bass from the sub.

It is killing me to have this good of a sound system, with it sounding so poor.

[Jonathan]

I honestly can't answer why Focal would design the K3Ps like they did, I mean the 6.5" midbass and the dedicated midrange are so similar to one another in that regard, it only offers a tiny bit more output. You figure they'd at least give you a badass high output midbass driver to mate with a 6.5" midrange driver, or design a midrange driver that could be pushed to 6khz or so without energy storage issues (like the Utopia 3" driver they use in the No 7. set). Honestly there really isn't anything you can do to get that midbass driver to dig deeper, it's similar to the Rainbow Kickbasses in regard to low end. It should have good output to around 80hz, though, how is it in that regard?

I don't know if you'd want to start swapping out stuff or not, but I feel one of the best drivers for your type of application is a Peerless XLS 8" (Solen is the only place that still has them). It's very efficient, it digs deep IB, and it sounds fantastic up to 300-400hz. Tons of output capability of of that, and it has no trouble doing 20hz. Your doors will have trouble doing 20hz, however, 40hz is more realistic even in the most heavily deadened of doors It is 8 ohm, though, and you'd have to be prepared to power it.

[geolemon]

well then here is another question for you...If they can customize the crossover from these, why does my system have virtually no midbass? Recognizing that the midbass driver doesn't have the phase plug, could it be cause i am running the passive x-overs rather than going all active?
Also, while I am on the subject, would it be better to rewire the amps to include the mid/tweet comps on one 2.150, and the midbass on the other 2.150, or continue with the 2.150 per side (tweet, mid, midbass)?
I just can't seem to get a decent amount of Midbass from these K3P's

The phase plug only helps a speaker play HIGHER... and isn't even any help unless you are trying to play that speaker SO high, that the wavelengths start to get smaller than the diameter of the cone - otherwise, it's really no benefit at all. ]"Doors are not speaker cabinets"[/b]
Repeat this mantra, over and over.
Then... think about how you CAN make your doors work like speaker cabinets.

Why?
Because if you don't - you won't have midbass.
Why?
Picture a speaker moving... cone moving in and out as fast as a hummingbirds wings, right? Slow it down... picture it in slow motion:
Cone moves out... pressurizes the air in front of the cone... but decompresses the air behind the cone.
Cone moves back in... decompresses the air in front of the cone, but compresses the air behind the cone.
If there was no enclosure... the compressed air would get sucked instantly into the vacuum on the other side of the cone - that IS what cancellation IS!

That's WHY you put a subwoofer into a box... with a sealed box, you're largely imprisoning that "rear of cone" sound energy, so it can't cancel the "front of cone" sound energy.
With a ported box, all you are doing is using a nifty trick to "recycle" the sound energy inside the box, slowing it relative to (ie. most efficiently at) one particular frequency, so that it contributes positively rather than negatively, increasing output rather than cancelling output.

Pop that door panel off - if you can reach around and touch the back of the speaker, you're going to have cancellations...
The smaller the distance between "speaker" and "holes sound can leak around", the higher up in frequency that cancellation will start to begin.
(get high enough in frequency, and it stops becoming an issue - wavelengths get small enough that it's almost hard to GET cancellations! )

I generally spend a small fortune in aluminum-backed damping material to fix this issue... some of it of course goes right inside the door cavity, to damp my door skin - but most of it, 3/4 or so even, goes to layering multiple layers over any access holes in the door, roughly "sealing" the door.
(tip: Do not EVER seal the drain holes in the bottom of the door! If water can't get out, that's a bad thing!)

If your doors are working well enough as cabinets - even a pair of old coaxials can produce surprising midbass... to say nothing of having a speaker that's actually got a good excursion to it.

If you do this, and don't have midbass still - you may have simply wired one of the two midbass drivers out of phase - and are having the same sort of cancellation issue - but between the two speakers, fighting each other.
(you can use a 9v battery to check your polarity - cool trick! )

[OnYrMrk]

well check out the hushmat pics from my install ok...I think I have plenty of matting to keep out the air. But you be the judge:

[Jonathan]

How do you have that midbass mounted, MDF or Plywood ring I'm guessing?

You can always go further and keep adding more and more deadener to make it even better, but that install is easily good enough that you shouldn't have issues with anything. Assuming correct polarity those midbasses should be performing to their potential. I'm thinking it's either a power issue (be it simply a lack of or a level matching issue since you have dash mounted mids and tweets), or it's simply the shape/size of your doors in relation to the driver parameters. BTW, add a deflex pad behind the midbass driver, it will help a bit.

Still, though, that hands off to the midrange at 300hz, right? Are you lacking over the entire range of that midbass (say 80-300hz), or simply below 100hz or so? I'd recommend you try to better level-match the drivers (turn down the mids and tweets, put more power on the midbasses). The x-over and amplification you proposed will be able to pull this off and see how it does. If that still doesn't net good results, then you may want to upgrade to the "OMG, that thing is SICK" level of midbass drivers

[OnYrMrk]

How do you have that midbass mounted, MDF or Plywood ring I'm guessing?

You can always go further and keep adding more and more deadener to make it even better, but that install is easily good enough that you shouldn't have issues with anything. Assuming correct polarity those midbasses should be performing to their potential. I'm thinking it's either a power issue (be it simply a lack of or a level matching issue since you have dash mounted mids and tweets), or it's simply the shape/size of your doors in relation to the driver parameters. BTW, add a deflex pad behind the midbass driver, it will help a bit.

Still, though, that hands off to the midrange at 300hz, right? Are you lacking over the entire range of that midbass (say 80-300hz), or simply below 100hz or so? I'd recommend you try to better level-match the drivers (turn down the mids and tweets, put more power on the midbasses). The x-over and amplification you proposed will be able to pull this off and see how it does. If that still doesn't net good results, then you may want to upgrade to the "OMG, that thing is SICK" level of midbass drivers

mdf 5x7 ring with a 6.5" opening. Works really nice and it is husmatted in too.

[geolemon]

I can't get the last three pictures up - database error?

Assuming all looks well though - have you checked the phase on the midbass drivers? You can "click" them with a 9v battery to confirm speaker phase, and then wire accordingly.

[geolemon]

I can't get the last three pictures up - database error?

Assuming all looks well though - have you checked the phase on the midbass drivers? You can "click" them with a 9v battery to confirm speaker phase, and then wire accordingly.

[OnYrMrk]

I can't get the last three pictures up - database error?
Assuming all looks well though - have you checked the phase on the midbass drivers? You can "click" them with a 9v battery to confirm speaker phase, and then wire accordingly.

I can't get the last three pictures up - database error?
Assuming all looks well though - have you checked the phase on the midbass drivers? You can "click" them with a 9v battery to confirm speaker phase, and then wire accordingly.

only when you double post..LOL...anyway..here are the last three photos, one post at a time

[OnYrMrk]

here is the 4th one