Overtaxed

Earlier I've changed out my speakers and I also got a 12" bass running off a separate amp.



Today I went back to my installer since I feel that the setup lack some mid-bass. They listen to it and agreed. They also took a measurement that confirmed it.



After some testing we came to the conclusion that there is a considerable gap between the factory amp's cut-offs to the "speakers" (mid/high) and the sub.



It's like the sub get everything up to 50-60 Hz and the mids/highs get 80-90 Hz and up, and in between there is pretty much nothing.


Anyone who can confirm or deny?

Kaban

What size speakers are you using? There is no cross over built in the amp. There is a high pass in the Tweeters and the Sub itself has a built in x-over.

I think the lack of mid bass could be the result of woofers been too small and not making enough low end.

Maybe Percy and Mean Gene can find out what's wrong as they are the electronic pros here.

Overtaxed

Kaban,





Thanks. But are you sure? I've listened to the speakers (5 inch) separately and they have a very full mid bass. But if you play them in my car with the sub disconnected there is absolutely no bass. They sound like they are cut off high. Anyone can tell within three seconds that there is not a hint of mid coming out of them.





The JBL amp that powers the sub has a crossover but when in my car you can't hear any difference if that is set at 80 Hz or 400 Hz. It uses the high level output for the subwoofer from the factory amp as input. I strongly doubt that the sub can't play over 80 Hz.





So when the speakers and the sub should overlap there is in fact a wide gap between them.

Kaban

Yes I am about 99% sure there is no xover built in the amp as past thread posted by Percy said there isn't any, and he modded out his system extensively. Plus the tweeters and sub both have a xover that could explain the amp doesn't have one.

But I am a bit confused on your last post, you said when you listened to the 5" separately there is full mid bass, but disconnect the sub then there is no bass. But if the 5" mids have full mid bass then aren't all the bass suppose to go to the sub?

Could it be that the 12" sub you are using was just not designed to produce too much mids?

Overtaxed

OK, I'll try and find the other thread. I wonder where the sub crossover is placed, because it's not ON the sub (if it's not very small and intregrated into the sub). We didn't remove anything other than the sub when we put the 12" in, so the crossover must still be there somewhere.

My bass can play 15-2000 Hz, so that is not the problem.

I'm not sure what you mean by "But if the 5" mids have full mid bass then aren't all the bass suppose to go to the sub?".

If I hook up my speakers to another system outside my car they sound perfect.
When I play them in my car through the factory amp they completely lack mid bass. They start to drop of somewhere at 200 Hz and below 100 Hz there is just silence.

Percy

It's more like a combination of both the small speaker size and the speakers (small) capabilities themselves. The subs 50 to 60 crossover point is fine. Even if the levels are matched, they won't integrate with a 4 or even a 5 1/4 inch speaker (and some 6 1/2's) seamlessly. Which 5 1/4 speakers are you using? I know with MBQ's, even with the 6.5's, they don't work well below 100 or even 70 hz. Yep...you read it right...70 for a 6.5 inch speaker. Reason being is the material that they're using and the voice coil, but mostly the cone material. Listen to the MBQ OBJECTIVELY and you'll find out that it sounds quite lean.

The speakers that I'm aware of that WON'T sound lean (and thus will have better midbass response) are ones from /a/d/s, Boston and my favs, Dynaudio. I don't have any experience with Focal (Mean Gene can vouch for them though).

Just for kicks and grins, try crossing over, if possible, at 80 or even 100hz. It may not sound good, but it may do it as a "patch job" for a little while.

Which speakers are you using? Are they running full pass?

Percy

Overtaxed

Percy,













The speakers are Q-Comps from Amega. That is a Swedish brand and you probably never heard of them, but there is no doubt about their reputation over here. They are absolutely in the same class as Dynaudio, and Dynaudio is Danish so you know that scandinavians produce top quality.













They are only 5.25", but they are long throw and do have a very nice mid bass. Except when they are in my car and hooked up to my factory amp. Then the mid bass is just gone. When listening to them in the store and then in my car there is a world of difference. It's just silly. Believe me, the problem is NOT the speakers.








Today I started to wonder if they get enough air in the doors. The spec says they need at least 8 litres (2 gallons?). I guess it shouldn't be a problem, but a too small box would kill the bass, yes?







The manual recommends a high pass to filter out the lowest octaves if the speakers are used together with a sub, but we never installed one. There is a crossover for the tweeters, otherwise the mids run "full pass" (if I understand that term correctly). Amega seems proud of their crossover. Me, I don't understand a word they're saying.



All inductors are aircore type and capacitors of highest quality for sound quality only found in high-end home speakers. To make crossovers with high quality components with out correct crossover points is useless, that's why our crossovers uses a zobel network for the midrange driver and no less than three different L-pads for the tweeter. This ensures correct function of the crossover and gives flexibility for the user with three different output levels for the tweeter with out changing crossover points.

Percy

I've actually heard of Amega. Haven't heard any output from them in person but their reputation is good. My guess is that there probably isn't enough power to push the speakers, thus the loss in midbass. Also, the point of the small enclosure comes to mind. That will KILL any midbass there, but I haven't had any problems with the Dyns in this matter. The demo board audition probably had the ideal amount of airspace. I'm wondering if Amega was actually R/D tested for auto use. Most people will mistake Dyn home drivers as the same as their auto drivers. This isn't the case and as far as I know, they're the only one that R/D exclusively for the automotive enviroment. Most of the other companies won't spend that amount of money (literally MILLIONS) in that type of venture so they slap a different label saying it's ok for auto use.

Is there a site for these speakers?

Also, this is a translation for the technobabble.

" All inductors are aircore type

Inductors are just that...hollow air core. Nothing unusual.

"and capacitors of highest quality for sound quality only found in high-end home speakers."

Depends on which speakers they're comparing to. There's Solen, Musicap, Multicap, Hovland, etc. More than likely they're Solen...cost effective. A Hovland Musicap will run 50 bucks EACH. Almost nobody is that critical....well...almost. (grin)

"To make crossovers with high quality components with out correct crossover points is useless, that's why our crossovers uses a zobel network for the midrange driver

Zobel network. Balances the impedance over the entire range of the speaker using a combo of a cap and a resistor. Easy. Also used in 12db/oct networks if I remember correctly.

"and no less than three different L-pads for the tweeter. "

This just means 3 different resistive elements for the tweeter. Usually air core inductors that are variable in setting or 3 components that are of a different value.

"This ensures correct function of the crossover and gives flexibility for the user with three different output levels for the tweeter with out changing crossover points.

Ok...3 different settings using inductors or some sort of resisitive component.

"Excuse me Miss....I speak Jive" (Airplane)

Percy

Overtaxed

Thanks Percy!



So, just to make this clear, you are absolutely positively sure that the signal from the factory amp is "pure" (full pass)? No high pass/crossover? There is no way to blame the amp (except possibly for being too week) for the lack of mid bass?



Is there a crossover for the factory sub? Where is it? I haven't found one.



Amega is 100% for auto use, so that's were all their R/D goes.



They have a site, but it's "under construction" and useless, so I will not even give you the address because it reflects poorly on my speakers.



So my next move will be to throw out the factory amp and the cd/radio and install top grade stuff and hope that will cure my problem. I was hoping it wouldn't have to come to this.

Percy

As far as I know, the signal for the midrange is pretty much high passed from 80 hz up. That's from listening experience. There isn't any passive component used for the midrange/midbass driver so it's probably built into the amp and electronicly passed. When I took out the original 4 inch rounds, they didn't have a crossover whatsoever. But, 4 inch rounds can only take so much bass so I'm guessing that the amp has a electronic crossover of some sort. Non adjustable of course. Wouldn't make any sense for the 4 inchers to play 50hz or below.

Crossover for the factory sub is built into the amp.

Upgrade, upgrade, upgrade. A never ending battle!

Percy

Overtaxed

This is the best we've been able to do with what I've got now. Each vertical step is 3dB.
































I'll start looking for a good head unit tomorrow. It looks like it's going to be a struggle to fit something below the nav screen. There is not a full DIN height there.















I really like the active black panel design of Sony CDX-M770. But I'm not sure that I will be content with the sound quality.
Though I don't want to get too carried away either. I'm not putting up a dime over $800.