Attention all members!
Have a cool ride? Then show it off on our website! All vehicles welcome!
Have a cool ride? Then show it off on our website! All vehicles welcome!
newbie sub help
newbie sub help
i have a 01' trans am and installed a new head unit a few months ago, mainly for mp3 use. the bass is really erratic though from song to song with excessive vibration (not sure of the proper term for that.) the rear seat panels are dual voice coil subs that produce only bass controlled by the factory amp. i tried different settings with the HPF and everything else, but it's not what i want. other than the bass, i'm perfectly fine with the sound. would it improve if i replaced the subs, or make it worse? any help would be appreciated.
Red light #1 - "mainly for MP3 use".
Why would that create suspicion? Because even standard CD's can be recorded poorly - I own too many CD's that I can count that have poor acoustics. But MP3's are never any better than the CD recording they were created from, and whoever encodes them has the freedom to decide how much they want to compress them - best case, it's close to CD quality. Worst case - it's highly compressed - nice file size, but inherently can cause many of the symptoms you describe - particularly poor bass response. Downloading these things? Easy, so easy that the problem could just be differences in one MP3 from another, as you don't have any control over the quality of any MP3 you download.
As a matter of fact, there's really nothing about the system that would cause the symptoms that you describe, except possibly the box.
Remember, the box controls what the bass sounds like, not the sub (although the sub has certain properties to it that makes it more or less compatible with a specific enclosure design
keep that in mind).
Possibility #2:
Your box is very small and/or tuned high and/or you have some sort of "bass boost" or "loudness" or you have the bass turned up on the deck, etc.
Box first:
Hoffman's Iron Law - you can search for that.
A small box makes every sub inefficient, and compromises low bass response.
Tuning a ported box increases efficiency, but compromises low bass response.
If you compromise low bass response, it'll create a situation where you don't have a smooth frequency response - you've got higher bass, but then the low bass falls off. And the symptom being you have "certain songs" that hit... and certain songs that "miss".
Similar for the bass boost / loudness / bass control / etc:
These are all EQ things, and not very well controlled ones at that. So, you have the same effect - you boost some narrow band of frequencies (every EQ of any type has a "Q" - the width of the band of frequencies that it affects - and it's inherently parabolic in shape, not flat - hence why everyone on any audio forum tells you to defeat these evil things )... and end up with certain songs that "hit" and certain songs that "miss".
You tell us which sounds the most like the symptoms you are experiencing.
Why would that create suspicion? Because even standard CD's can be recorded poorly - I own too many CD's that I can count that have poor acoustics. But MP3's are never any better than the CD recording they were created from, and whoever encodes them has the freedom to decide how much they want to compress them - best case, it's close to CD quality. Worst case - it's highly compressed - nice file size, but inherently can cause many of the symptoms you describe - particularly poor bass response. Downloading these things? Easy, so easy that the problem could just be differences in one MP3 from another, as you don't have any control over the quality of any MP3 you download.
As a matter of fact, there's really nothing about the system that would cause the symptoms that you describe, except possibly the box.
Remember, the box controls what the bass sounds like, not the sub (although the sub has certain properties to it that makes it more or less compatible with a specific enclosure design
keep that in mind).Possibility #2:
Your box is very small and/or tuned high and/or you have some sort of "bass boost" or "loudness" or you have the bass turned up on the deck, etc.
Box first:
Hoffman's Iron Law - you can search for that.
A small box makes every sub inefficient, and compromises low bass response.
Tuning a ported box increases efficiency, but compromises low bass response.
If you compromise low bass response, it'll create a situation where you don't have a smooth frequency response - you've got higher bass, but then the low bass falls off. And the symptom being you have "certain songs" that hit... and certain songs that "miss".
Similar for the bass boost / loudness / bass control / etc:
These are all EQ things, and not very well controlled ones at that. So, you have the same effect - you boost some narrow band of frequencies (every EQ of any type has a "Q" - the width of the band of frequencies that it affects - and it's inherently parabolic in shape, not flat - hence why everyone on any audio forum tells you to defeat these evil things
)... and end up with certain songs that "hit" and certain songs that "miss".You tell us which sounds the most like the symptoms you are experiencing.
-
Ryan from Ohio
- Posts: 13308
- Joined: Fri Mar 17, 2000 12:00 pm
- Contact:
I dunno Geo.
He has a factory amp?
Is that powering factory subs?
He has a factory amp?
Is that powering factory subs?
-Ryan
www.caraudiocentral.net - Your #1 Car Audio Resource on the Net!
www.caraudiocentral.net - Your #1 Car Audio Resource on the Net!
Factory amp that has HPF and LPF settings??
I think we need to learn a little more about the actual equipment in this install.
Besides - from his description of what he is playing, I've got an equal amount of suspicion of the garbage he might be feeding into the system...
You know how it is - you can have a system that measures up to true audiophile standards, and it's still only as good as the music you feed into it.
In fact, one of the first things that an enthusiast usually notices - make that, is suprised by - when they get their first real high-end system complete, is that they can suddenly quite easily identify a good recording from a bad one. I'm sure you know exactly what I'm talking about, and that's exactly why I opened with my primary comment on MP3's. His comment on the lack of bass / poor bass quality reflects people's complaints about MP3 and other compression formats - it's the compression, that's my primary suspicion, since he mentioned that some songs sound OK.
I think we need to learn a little more about the actual equipment in this install.
Besides - from his description of what he is playing, I've got an equal amount of suspicion of the garbage he might be feeding into the system...
You know how it is - you can have a system that measures up to true audiophile standards, and it's still only as good as the music you feed into it.
In fact, one of the first things that an enthusiast usually notices - make that, is suprised by - when they get their first real high-end system complete, is that they can suddenly quite easily identify a good recording from a bad one. I'm sure you know exactly what I'm talking about, and that's exactly why I opened with my primary comment on MP3's. His comment on the lack of bass / poor bass quality reflects people's complaints about MP3 and other compression formats - it's the compression, that's my primary suspicion, since he mentioned that some songs sound OK.
I agree with Geo on this.... we need details of this factory system to give any real advice... (or I do at least )
)-Michael
http://www.teamcargodzinc.com
Hear It, See It, Feel It, Punch It!
And Proud Sponsor of
Team Wolf Pack Audio
Authorized Dealer
http://www.teamcargodzinc.com
Hear It, See It, Feel It, Punch It!
And Proud Sponsor of
Team Wolf Pack Audio
Authorized Dealer
-
Ryan from Ohio
- Posts: 13308
- Joined: Fri Mar 17, 2000 12:00 pm
- Contact:
Ya some of them MP3s are just dog poop
-Ryan
www.caraudiocentral.net - Your #1 Car Audio Resource on the Net!
www.caraudiocentral.net - Your #1 Car Audio Resource on the Net!
sorry. it's just the factory setup (monsoon 10 speaker system) minus the head unit that i installed. i got the unit from crutchfield and asked a tech about the bass afterwards. he said it was due to the inconsistencies in mp3's and my best option was to mess around with the controls until i found the sound that best fits. for the subs in the rear seat panels, they give this description..
"The factory dual voice coil subwoofer in this location receives only bass frequencies from the amplifier. If replaced with an aftermarket speaker, the aftermarket speaker will only reproduce bass."
i've read elsewhere the amp has no adjustable settings on it. also, i'm able to use the HPF on the subs from the head unit. for example; with a cd of 100 random mp3's and the HPF setting on 80, the bass is strong, but has excessive vibration from the subs on about 50 of the songs. on 100, the bass is good, but not as strong and has the vibration on about 25. on 120, there is basically no bass at all. i've tried a ton of different settings, but it seems impossible to find one that brings decent bass without the vibration. i could put the EQ on flat or vocal, but the sound is horrible then. i understand the problems with mp3's and all, but i have trouble believing i have to live with crap bass or bad vibration as my only 2 choices? i usually reencode them to a high VBR, but no way would i have the time to individually adjust the bass so it's more playable in my ride, nor would i want to.
"The factory dual voice coil subwoofer in this location receives only bass frequencies from the amplifier. If replaced with an aftermarket speaker, the aftermarket speaker will only reproduce bass."
i've read elsewhere the amp has no adjustable settings on it. also, i'm able to use the HPF on the subs from the head unit. for example; with a cd of 100 random mp3's and the HPF setting on 80, the bass is strong, but has excessive vibration from the subs on about 50 of the songs. on 100, the bass is good, but not as strong and has the vibration on about 25. on 120, there is basically no bass at all. i've tried a ton of different settings, but it seems impossible to find one that brings decent bass without the vibration. i could put the EQ on flat or vocal, but the sound is horrible then. i understand the problems with mp3's and all, but i have trouble believing i have to live with crap bass or bad vibration as my only 2 choices? i usually reencode them to a high VBR, but no way would i have the time to individually adjust the bass so it's more playable in my ride, nor would i want to.
When you say vibration, are you talking panel vibration? To much bass? I am a little lost in all of this, so set me straight if need be.
but has excessive vibration from the subs on about 50 of the songs
Can you clarify this. What I am understanding is that some of the songs have more bass then others correct? That has to do with a couple of things. Number 1, quality of recording, and 2, frequency of the bass notes in the songs. Have you tried turning off the HPF on the deck. From what you told us that amp already crosses the highs, so it is not necessary that you do so from the deck.
but has excessive vibration from the subs on about 50 of the songs
Can you clarify this. What I am understanding is that some of the songs have more bass then others correct? That has to do with a couple of things. Number 1, quality of recording, and 2, frequency of the bass notes in the songs. Have you tried turning off the HPF on the deck. From what you told us that amp already crosses the highs, so it is not necessary that you do so from the deck.
Well I hate to say this and please don't take it personally, but your largest problem is that factory monsoon set up.
I've had many dealings with these and compared with a stock delco system they are much better, but compared to what is available in the aftermarket, not even close... and by upgrading your h/u you really didn't do the overall system any favor as they are specifically built to provide the best sound in conjuction with all of the components.
Now that's not to say that crutchfield is wrong, it just combines the problems.
If you upgrade your factory amp/ sub combo (something the h/u has more control over), you will be much more likely to find settings more to your liking.
I've had many dealings with these and compared with a stock delco system they are much better, but compared to what is available in the aftermarket, not even close... and by upgrading your h/u you really didn't do the overall system any favor as they are specifically built to provide the best sound in conjuction with all of the components.
Now that's not to say that crutchfield is wrong, it just combines the problems.
If you upgrade your factory amp/ sub combo (something the h/u has more control over), you will be much more likely to find settings more to your liking.
-Michael
http://www.teamcargodzinc.com
Hear It, See It, Feel It, Punch It!
And Proud Sponsor of
Team Wolf Pack Audio
Authorized Dealer
http://www.teamcargodzinc.com
Hear It, See It, Feel It, Punch It!
And Proud Sponsor of
Team Wolf Pack Audio
Authorized Dealer
Not sure on '01 vehicles, but - ironically enough - you may have eliminated something important when you replaced the factory head unit!
Many vehicles these days (particularly with "premium systems") have a built-in fixed equalization circuit, meant essentially to compensate for the generally sub-par speakers that they want to get away with installing into the new car.
It's not a bad idea - it means a factory system can sound better than it otherwise would have, given those crappy factory speakers. At least it will have a relatively flat frequency response, even if the transient response isn't so great - non audiophiles wouldn't notice.
But what that means is that your factory HU isn't sending out a "flat" response signal to the speakers - it's sending out some signal that's not flat, some signal that's compensating for certain deficiencies in those speakers.
If that's the case with this GM head unit, that means you removed a signal source that was helping compensate for your speaker's deficiencies, and replaced it with one that isn't.
This sort of situation is exactly the reason that JL Audio makes it's Clean Sweep integration products, btw... and why Rockford has the 3sixty.1 and 3sixty.2 with the built-in 32 band-per-channel EQ... and why Audiocontrol makes its LC6 and new DQX8... etc.
If those subs in the back have some "previously EQ'd out" peak in the response that is no longer being EQ'd out, that could also cause the symptoms you describe - caused directly by the HU replacement.
Or - it still could be the two reasons I mentioned earlier (three, really).
Many vehicles these days (particularly with "premium systems") have a built-in fixed equalization circuit, meant essentially to compensate for the generally sub-par speakers that they want to get away with installing into the new car.
It's not a bad idea - it means a factory system can sound better than it otherwise would have, given those crappy factory speakers. At least it will have a relatively flat frequency response, even if the transient response isn't so great - non audiophiles wouldn't notice.
But what that means is that your factory HU isn't sending out a "flat" response signal to the speakers - it's sending out some signal that's not flat, some signal that's compensating for certain deficiencies in those speakers.
If that's the case with this GM head unit, that means you removed a signal source that was helping compensate for your speaker's deficiencies, and replaced it with one that isn't.
This sort of situation is exactly the reason that JL Audio makes it's Clean Sweep integration products, btw... and why Rockford has the 3sixty.1 and 3sixty.2 with the built-in 32 band-per-channel EQ... and why Audiocontrol makes its LC6 and new DQX8... etc.
If those subs in the back have some "previously EQ'd out" peak in the response that is no longer being EQ'd out, that could also cause the symptoms you describe - caused directly by the HU replacement.
Or - it still could be the two reasons I mentioned earlier (three, really).