[constantin_md]

I did a full aftermarket radio, 5.25'' morel virtus speaker upgrade and
I installed a pair of sws-8x to a jl xd700/5.
both speakers and subs are crossed at 80hz 24db. Morel hit too low on 12db at 80hz and i'm afraid to burn them.
50% gain on speakers, 70% gain on subs

The sws-8x hit amazingly hard and deep on low notes, but on most songs they are barely audible, even on high volume. Also when i go past 50-60% volume the subs start distorting and seem much less audible.

I had high hopes for the sws-8x, but they fell short.
Is there any way to improve the sound? I put some gtmat sound deadening inside the enclosure, cut the carpet around the sub. put 2 nuts on each bolt between carpet and grill so the grill is raised a bit. No rattles of any kind are present.

I bought some "Sonic Barrier" acoustic foam and will try to improve the upper notes. I understand that the poly-fill is for lower notes, right? So i should not need it. There is plenty of low notes with sws-8x but upper notes fall off terribly.
Did anyone try to seal the sub enclosure? Would the enclosure's volume be enough for the sub?

[qtvivi]

I want to do an audio upgrade soon. How did you wire this up, and do you have a sun in the trunk?

[constantin_md]

Originally Posted by qtvivi

I want to do an audio upgrade soon. How did you wire this up, and do you have a sun in the trunk?

Here is a collection of diy and diagrams
https://mega.co.nz/#F!5JYRRKwQ!J99Nkp8YgsjPwrWd48Y_vA

I don't have a sub in the trunk.

[cdgatti]

you may want to try doing a raising your low pass frequency on the underseats, it is ok for them to cross with the door speakers. try moving them up slowly to 150 as you listen to music see if they start to become audible.

[david in germany]

With my MS-8 install in my e87 I found that the best crossover frequency between the underseats and the mid range was around 200hz.

[kaigoss69]

Did you try reversing polarity of the Earthquakes?

[constantin_md]

Originally Posted by david in germany

With my MS-8 install in my e87 I found that the best crossover frequency between the underseats and the mid range was around 200hz.

You probably have 4'' speakers.
I don't have any issues with the 80hz+ because Morel Virtus 502 5.25'' play more midbass than i ever wanted. The issue i have is with the subs around 50 to 80hz.
The funny thing is that the morel speakers are much louder than the subs at 1/3 the wattage(50w) given to them compared to the subs(150w). I wish the sound was more balanced. The subs are much louder only if they play 30 to 50hz notes.
This is definitely not a sub issue, but the enclosure's and the inside air not circulating right for the sub parameters.

[constantin_md]

Originally Posted by kaigoss69

Did you try reversing polarity of the Earthquakes?

I'll give it a try. Is reversing the polarity and turning on reverb on the radio the same thing?

BTW I see that you have idmax15, how do those compare to the idmax12?
Idmax12 was one of my favorite sub, unfortunately they could not take more than 650w in a sealed box. Fi q12 sounded just as good with much more power handling. I wish i still had it.

[constantin_md]

Originally Posted by cdgatti

you may want to try doing a raising your low pass frequency on the underseats, it is ok for them to cross with the door speakers. try moving them up slowly to 150 as you listen to music see if they start to become audible.

I'll give it a try. If nothing works, i'll seal the sub enclosures. The subs seem to play like they are in free air.

[kaigoss69]

Originally Posted by constantin_md

I'll give it a try. Is reversing the polarity and turning on reverb on the radio the same thing?

BTW I see that you have idmax15, how do those compare to the idmax12?
Idmax12 was one of my favorite sub, unfortunately they could not take more than 650w in a sealed box. Fi q12 sounded just as good with much more power handling. I wish i still had it.

Reversing the polarity will inverse the phase of the woofers. This may reduce/remove any potential cancellations between the underseats and door mids (which may be responsible for the low output near the crossover point). You may be able to do this with your DSP without physically swapping speaker wires.

I've never heard the IDMax 12, but the 15 has been my best subwoofer ever.

[kaigoss69]

Originally Posted by constantin_md

I'll give it a try. If nothing works, i'll seal the sub enclosures. The subs seem to play like they are in free air.

It is sort of a free air enclosure because it vents into the side sill cavities, which are not air tight. If you seal off the plastic enclosure under the seat, it would give the sub approximately 0.07 ft.³ of air space, which would actually make things worse. If you want to do it right, put in a true mid bass driver under the seats, and a true sub in the trunk. What you have is neither.

[david in germany]

Originally Posted by constantin_md

You probably have 4'' speakers.
I don't have any issues with the 80hz+ because Morel Virtus 502 5.25'' play more midbass than i ever wanted. The issue i have is with the subs around 50 to 80hz.
The funny thing is that the morel speakers are much louder than the subs at 1/3 the wattage(50w) given to them compared to the subs(150w). I wish the sound was more balanced. The subs are much louder only if they play 30 to 50hz notes.
This is definitely not a sub issue, but the enclosure's and the inside air not circulating right for the sub parameters.

I would still bring up the highpass on the door speakers and also try bringing down the lowpass on the underseats. they still have too much overlap at 24db at the same xover frequency.. The only reason to run a midrange with a low cutoff is to give it more bass up front but you have the Earhquakes which will fullfill that duty. Also do not expect the Earhquakes to run under about 38-40hz unless you want to see some majic smoke.

[kaigoss69]

Originally Posted by david in germany

I would still bring up the highpass on the door speakers and also try bringing down the lowpass on the underseats. they still have too much overlap at 24db at the same xover frequency.. The only reason to run a midrange with a low cutoff is to give it more bass up front but you have the Earhquakes which will fullfill that duty. Also do not expect the Earhquakes to run under about 38-40hz unless you want to see some majic smoke.

You always want to run the door mids as low as they can play. This has more to do with imaging than mid-bass response. Furthermore, you want extend the FR of the better sounding speaker as much as possible, for obvious reasons. That's why those Morels in this position are a very good option, if you can live with the non-OEM look.

The reason why most people have had best luck with a crossover between 200 and 300Hz is simply due to the midrange's inability to play anywhere below that. Most 4" mids fall into that category. But in that case you will have the imaging pulling down. Some people deny that, simply due to the fact that they have not experienced the sound of a door mid playing 100Hz with authority. Once you hear that, there simply is no going back.

[david in germany]

Originally Posted by kaigoss69

You always want to run the door mids as low as they can play. This has more to do with imaging than mid-bass response. Furthermore, you want extend the FR of the better sounding speaker as much as possible, for obvious reasons. That's why those Morels in this position are a very good option, if you can live with the non-OEM look.

The reason why most people have had best luck with a crossover between 200 and 300Hz is simply due to the midrange's inability to play anywhere below that. Most 4" mids fall into that category. But in that case you will have the imaging pulling down. Some people deny that, simply due to the fact that they have not experienced the sound of a door mid playing 100Hz with authority. Once you hear that, there simply is no going back.

I agree with you 100% in a normal car without the space for an underseat woofer. Think 2 way system, Midbass needs to go as low as it can to get the best inaging. Now think 3 way system, (what we have in our BMW's) woofer or in our case extended low range underseat midbass. The image will still be strong with a higher frequency to your mid range and you can get more out of your underseat Mid Bass/woofer. If your frequencies are set properly there will be no "pulling the stage down" I have done numerous installs with kick panel tweeters and no one has ever said, "your sound stage is too low" Crossover settings are easy to adjust so try it, if you don't like it that way, change it back.

[kaigoss69]

Originally Posted by david in germany

I agree with you 100% in a normal car without the space for an underseat woofer. Think 2 way system, Midbass needs to go as low as it can to get the best inaging. Now think 3 way system, (what we have in our BMW's) woofer or in our case extended low range underseat midbass. The image will still be strong with a higher frequency to your mid range and you can get more out of your underseat Mid Bass/woofer. If your frequencies are set properly there will be no "pulling the stage down" I have done numerous installs with kick panel tweeters and no one has ever said, "your sound stage is too low" Crossover settings are easy to adjust so try it, if you don't like it that way, change it back.

Like I said, if you've never heard it...

Think about this...if the midrange is capable of playing 100Hz with authority (and as loud as you'd ever want it to play), why would you NOT have them play that frequency? I have 10" harcore, dedicated midbass drivers under the seats. If I had them in the doors, or in the kicks (if that were physically possible), I would probably have them playing higher. However, I have tried numerous different crossovers with these underseats, and the lower I go, the better the imaging gets. Right now I have it set at 100Hz, because the JBL door mids can take it all day. Any musical notes or voices that dip into the bass region, like deep voices (e.g. Johnny Cash), or guitar strings, or kick drums, are firmly anchored on the dashboard where they belong. When I had the x-over at 160Hz - I was using different mids that maxed out at 160 - the image got stretched height-wise, and I could hear the underseats play part of the notes, which at the time was "normal" for me. Now that I have the JBLs, the difference is night and day! What a difference 60Hz makes! Of course, the higher you go with the crossover, the more the underseats play. At around 150 - 250Hz, there is a nasty floorboard resonance that gets added into the mix and makes things even worse. And believe me when I tell you, there is no amount of EQ or TA, or whatever you can apply to get rid of that, and to firmly plant the imaging of the entire frequency spectrum onto the dash. The only way you do that is with proper crossover point selection (and of course having the drivers that are capable of playing in those frequency ranges).

[BMWe90R.O.D.]

thanks for the wiring diagrams---much appreciated

[david in germany]

Originally Posted by kaigoss69

Like I said, if you've never heard it...

Think about this...if the midrange is capable of playing 100Hz with authority (and as loud as you'd ever want it to play), why would you NOT have them play that frequency? I have 10" harcore, dedicated midbass drivers under the seats. If I had them in the doors, or in the kicks (if that were physically possible), I would probably have them playing higher. However, I have tried numerous different crossovers with these underseats, and the lower I go, the better the imaging gets. Right now I have it set at 100Hz, because the JBL door mids can take it all day. Any musical notes or voices that dip into the bass region, like deep voices (e.g. Johnny Cash), or guitar strings, or kick drums, are firmly anchored on the dashboard where they belong. When I had the x-over at 160Hz - I was using different mids that maxed out at 160 - the image got stretched height-wise, and I could hear the underseats play part of the notes, which at the time was "normal" for me. Now that I have the JBLs, the difference is night and day! What a difference 60Hz makes! Of course, the higher you go with the crossover, the more the underseats play. At around 150 - 250Hz, there is a nasty floorboard resonance that gets added into the mix and makes things even worse. And believe me when I tell you, there is no amount of EQ or TA, or whatever you can apply to get rid of that, and to firmly plant the imaging of the entire frequency spectrum onto the dash. The only way you do that is with proper crossover point selection (and of course having the drivers that are capable of playing in those frequency ranges).

Brother, we agree on a lot! But we are talking about somone else's system with completely different drivers and processing capabilities. What has worked for us may not work for him. Too bad you are not in Germany because I would love to sit down over a couple of beer and talk audio or show you my old school collection.

[kaigoss69]

Originally Posted by david in germany

Brother, we agree on a lot! But we are talking about somone else's system with completely different drivers and processing capabilities. What has worked for us may not work for him. Too bad you are not in Germany because I would love to sit down over a couple of beer and talk audio or show you my old school collection.

Haha yes we jacked this thread pretty good, didn't we? If you're close to Stuttgart, send me a PM, I go there once or twice a year.

[constantin_md]

thank you so much for advice everyone, very helpful.
I listened more carefully to the audio today and i figured it out. Some beats in music were bouncing from speaker to subwoofers to speakers and that was causing some disappointment. Speakers at 80hz 24db and subs at 80hz 24db were not blending right. Getting subs to 80hz 12db solved the problem.
One small issue i still have is that the subs sound a little boomy past 50% volume, like an echo right after each note. Hopefully will solve that with some acoustic foam.

[kaigoss69]

Originally Posted by constantin_md

thank you so much for advice everyone, very helpful.
I listened more carefully to the audio today and i figured it out. Some beats in music were bouncing from speaker to subwoofers to speakers and that was causing some disappointment. Speakers at 80hz 24db and subs at 80hz 24db were not blending right. Getting subs to 80hz 12db solved the problem.
One small issue i still have is that the subs sound a little boomy past 50% volume, like an echo right after each note. Hopefully will solve that with some acoustic foam.

Lol ok. Seems to have been a phase issue, since changing the crossover from 24 to 12 essentially reversed the phase 180 degrees. I'd recommend putting it back at 24 and reversing polarity. You don't want those earthquakes playing any higher than they have to.

[qtvivi]

Hey OP, did you take any pictures during your installation?

[constantin_md]

thanks kaigoss69, i'll give it a try.

here is my installation qtvivi
http://www.e90post.com/forums/showthread.php?t=1126014