Need help: Ported Sub vs. something like a shaker?

[hoppy6698]

Okay, so I have an ID10 ported sub in the trunk, custom box, 250w RMS amp, etc. However, while I wanted a little more "hit" than the B&O (pitiful sub), the 10 is far too hard hitting for my sound preferences. I like how it rocks the car, but the thumping to my ears hurts too much (blame it on too much combat and loud gunfire).

Would a shaker or something else work to provide the 'thump' feeling without hurting my ears? Is there any option that can just fit into the B&O sub location?

I really have no idea where to go now after trying the full sub setup.

Current Setup: 2009 Audi A4 w/ B&O sound
LC2i
ID10 v4 Sub in custom ported box
JBL 250W amp

Any help would be appreciated!

[hoppy6698]

Would something like this work or even fit?

http://www.sonicelectronix.com/item_...nd-SWS-8X.html

[subterFUSE]

How is the subwoofer tuned? Do you know the crossover settings? How high are the gains? What is the tuning frequency of the port?

You could always turn down that subwoofer to get lower output. Or you could try a sealed enclosure which would lower output and might be cleaner.

[hoppy6698]

How is the subwoofer tuned? Do you know the crossover settings? How high are the gains? What is the tuning frequency of the port?

You could always turn down that subwoofer to get lower output. Or you could try a sealed enclosure which would lower output and might be cleaner.

As far as I can tell, they tuned the sub to match the manufacturer specs. I have no clue about the crossover gains, only that the sub output is run separately through the LC2i and I have a remote in the center console to turn it up or down. I turn it down to near nothing most of the time. When it is off, I can tell the difference, but the B&O doesn't seem to have a lot of midrange bass I guess. So it ends up feeling all or nothing.

At this point, it seems quite a drain of $ just to try another box for something with a tighter feel.

[subterFUSE]

A subwoofer should be playing sub-bass frequencies, and not midrange or midbass. I have my subwoofers crossed-over from 20 Hz to 80Hz, with a 24 dB/octave slope.
If the subs are crossed too high, then the response will often become "boomy" and sloppy, and their location can be heard. (i.e. you can tell it is coming from behind)
With a properly tuned sub, it should be difficult to locate the origin of the sound.

If it was my car, I would want to know the following information:

1. Which output from the B&O amplifier did they tap for the LC2i? (i.e. subwoofer, rear midbass, etc..)
2. Did they test the B&O output with an oscilloscope to determine the freq. range of signal? If so, what was the range?
3. What are the crossover settings for the subwoofer? (Frequencies & Slope)
4. Did they test the maximum undistorted volume level of the B&O volume control? What was that volume level? (This must also be done with an oscilloscope.)


Here is why that information is critical:

A. The B&O amplifier probably contains an active crossover inside the amp. That means the amp will take a full range signal (20Hz - 20kHz) and divide it up among the various speakers. If the wrong output is tapped, then it might not deliver the desired range of frequencies for a subwoofer. In my Bose stereo in my S6, the front midbass speakers do not receive any bass frequencies at or below 40Hz when I tested them. Therefore, the only output I could tap in my car for a subwoofer was the actual subwoofer output on the Bose amp.
In your case, I feel confident they did tap the subwoofer.... but it's good to be sure, just in the interest of troubleshooting.

B. Once an output has been selected on the B&O, they should test it to see the frequency range of the signal it delivers. Hopefully, it will have a range from 20Hz up to 80 or 100Hz.

C. The crossover settings for the subwoofer are important. If the sub is crossed too high, then it will be overly loud and boomy. You will also want to be sure they are using a bandpass crossover, and not just a low pass. This is because you have a ported sub. The lower crossover setting should be set for the tuning frequency of the port. This will prevent damaging the sub and wasting power below the tuning freq.

D. Lastly, when using any kind of line converter it is important to know how high the B&O volume control can be turned before it distorts. This is a test that must be done with an oscilloscope and test signals. On my Bose, I am able to turn up to a volume level of 29/34. Therefore, that is the volume level which my BitOne has been set for. If the BitOne were set for a lower volume level than 29, it would cause the noise floor to be raised more than optimum. And if the max undistorted volume on the B&O is exceeded, then you'll be amplifying a clipped signal which is not good either.

[naiku]

You could always turn down that subwoofer to get lower output. Or you could try a sealed enclosure which would lower output and might be cleaner.

I would just do this as it is the cheapest option to start with. I would worry though that if you like the feel of the bass, but the sound hurts your ears, that you are going to have to pick one. If you turn the gain down then you may lose some of the feeling, but your ears will not bother you, if you leave it up then your ears will bother you but you keep the feel.

You could try an Aura Bass shaker but I have no experience with them.

[hoppy6698]

A subwoofer should be playing sub-bass frequencies, and not midrange or midbass. I have my subwoofers crossed-over from 20 Hz to 80Hz, with a 24 dB/octave slope.
If the subs are crossed too high, then the response will often become "boomy" and sloppy, and their location can be heard. (i.e. you can tell it is coming from behind)
With a properly tuned sub, it should be difficult to locate the origin of the sound.

If it was my car, I would want to know the following information:

1. Which output from the B&O amplifier did they tap for the LC2i? (i.e. subwoofer, rear midbass, etc..)
2. Did they test the B&O output with an oscilloscope to determine the freq. range of signal? If so, what was the range?
3. What are the crossover settings for the subwoofer? (Frequencies & Slope)
4. Did they test the maximum undistorted volume level of the B&O volume control? What was that volume level? (This must also be done with an oscilloscope.)


Here is why that information is critical:

A. The B&O amplifier probably contains an active crossover inside the amp. That means the amp will take a full range signal (20Hz - 20kHz) and divide it up among the various speakers. If the wrong output is tapped, then it might not deliver the desired range of frequencies for a subwoofer. In my Bose stereo in my S6, the front midbass speakers do not receive any bass frequencies at or below 40Hz when I tested them. Therefore, the only output I could tap in my car for a subwoofer was the actual subwoofer output on the Bose amp.
In your case, I feel confident they did tap the subwoofer.... but it's good to be sure, just in the interest of troubleshooting.

B. Once an output has been selected on the B&O, they should test it to see the frequency range of the signal it delivers. Hopefully, it will have a range from 20Hz up to 80 or 100Hz.

C. The crossover settings for the subwoofer are important. If the sub is crossed too high, then it will be overly loud and boomy. You will also want to be sure they are using a bandpass crossover, and not just a low pass. This is because you have a ported sub. The lower crossover setting should be set for the tuning frequency of the port. This will prevent damaging the sub and wasting power below the tuning freq.

D. Lastly, when using any kind of line converter it is important to know how high the B&O volume control can be turned before it distorts. This is a test that must be done with an oscilloscope and test signals. On my Bose, I am able to turn up to a volume level of 29/34. Therefore, that is the volume level which my BitOne has been set for. If the BitOne were set for a lower volume level than 29, it would cause the noise floor to be raised more than optimum. And if the max undistorted volume on the B&O is exceeded, then you'll be amplifying a clipped signal which is not good either.

Thanks! Thats a whole lotta science there that I cannot measure :P

I guess a follow up question - Anyone know of a good shallow mount sub that will fit in the stock B&O location? I already have the amp and LC2i in place, so either I reconnect the stock sub or replace it with something cleaner (stock one really stunk though).

[naiku]

I guess a follow up question - Anyone know of a good shallow mount sub that will fit in the stock B&O location? I already have the amp and LC2i in place, so either I reconnect the stock sub or replace it with something cleaner (stock one really stunk though).

I think the JL shallow mount subs are pretty decent, I think the 10" is a 10TW3, but I am not sure how big the stock B&O sub is to know if that will fit. There are some good 8" subs out there as well, the Pioneer TS-SW841D may work, I have no experience with these though.

If you end up selling the ID10, let me know as I might be interested in taking it off you.

[hoppy6698]

The ID10 with enclosure is for sale currently on Craigslist, Kansas City. Only one bite so far. I'm definitely leaning towards the pioneer shallow mount, has good open air review through multiple sites. Just wish I knew an audiohead nearby to consult with instead of pushy shops.

http://kansascity.craigslist.org/pts/4421659877.html


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[naiku]

Seems like a good price for the sub and box. GLWS.

Let me know if you want and I can see if any of the members on some car audio forums I am a member of can help.

[Luis_Heineken]

I would just do this as it is the cheapest option to start with. I would worry though that if you like the feel of the bass, but the sound hurts your ears, that you are going to have to pick one. If you turn the gain down then you may lose some of the feeling, but your ears will not bother you, if you leave it up then your ears will bother you but you keep the feel.

You could try an Aura Bass shaker but I have no experience with them.

they work great. i have some in my sofa, in the home theater room, bass feeling without the noise

[hoppy6698]

Seems like a good price for the sub and box. GLWS.

Let me know if you want and I can see if any of the members on some car audio forums I am a member of can help.

Please do, if you know people who want to purchase, let me know. Otherwise, by the end of June, the subwoofer and I will be in Seattle/Tacoma area.

Anyone else have experience with this shallow sub? Pioneer TS-SW841D - it seems to have a lot of good reviews for open air, drop in use.

[8520]

As a professional installer, here is my advice:

Buy a prefab 10" sealed box and turn your gains down a bit. Shouldn't cost much for the box. A 10 shouldn't be too boomy, it's likely the box.

[hoppy6698]

As a professional installer, here is my advice:

Buy a prefab 10" sealed box and turn your gains down a bit. Shouldn't cost much for the box. A 10 shouldn't be too boomy, it's likely the box.

Okay, so after some more research on setting up the LC2i gains and playing songs at 3/4 volume (as far as I could tell since Audi doesn't have a number system on the MMI) - I got the sub to perform consistently across different types of music (harder hit for rap, less so on rock/pop).

However - I noticed when the sub was turned off (I have a remote in the arm rest), the stock sub is still connected and playing on its own! I knew they left it in place (to keep the trunk sealed), but did not know it was still connected. Is this interfering or acting as something in the middle of the deep bass? Should it be disconnected? Even more, should I remove it or does it keep road noise isolated by being in place?

I'm still thinking B520 is right and a sealed box (which was my initial preference) is the way to go, but before I purchase one from Sonic, what do I do with the B&O stock sub?

[subterFUSE]

However - I noticed when the sub was turned off (I have a remote in the arm rest), the stock sub is still connected and playing on its own! I knew they left it in place (to keep the trunk sealed), but did not know it was still connected. Is this interfering or acting as something in the middle of the deep bass? Should it be disconnected? Even more, should I remove it or does it keep road noise isolated by being in place?

I'm still thinking B520 is right and a sealed box (which was my initial preference) is the way to go, but before I purchase one from Sonic, what do I do with the B&O stock sub?

This makes me worry about which output from the Bose amplifier was tapped for your subwoofer. The Bose sub should be disconnected, and preferably removed so it does not act as a passive radiator.

I would get over to the installer and ask to confirm which Bose output they used for the LC2i, and ask why the Bose sub is still connected. They should disconnect that Bose sub.

[hoppy6698]

This makes me worry about which output from the Bose amplifier was tapped for your subwoofer. The Bose sub should be disconnected, and preferably removed so it does not act as a passive radiator.

I would get over to the installer and ask to confirm which Bose output they used for the LC2i, and ask why the Bose sub is still connected. They should disconnect that Bose sub.

B&O, not Bose. There is a difference. The B&O amp still drives all other speakers.

[subterFUSE]

B&O, not Bose. There is a difference. The B&O amp still drives all other speakers.

My mistake on the B&O vs. Bose, but I would still check whether the stock subwoofer is still connected and playing. I don't think it should be.

[hoppy6698]

My mistake on the B&O vs. Bose, but I would still check whether the stock subwoofer is still connected and playing. I don't think it should be.

I did and said that it is playing before.


Sent from my iPhone using Telepathy.

[swoardrider]

My 2 cents:

OP, you could have other issues with the install (not giving the sub amp a flat, clean signal), but with what facts that you provided, I'm guessing that your that your sub is way over-powering your stock B&O, so your system is not very balanced.

You didn't mention whether you have the dual 2 ohm, or dual 4 ohm ID10?? If you running the dual 4 ohm sub, you are most likely running the amp at 2 ohms, as most installs don't run 8 ohms in car stereo. If this is the case, you could be running more wattage than just the 250 you posted.

Red flags
!. You could be running at 2 ohms. A majority of amps at 2ohms work harder, which cuts your dampening factor in half and increases THD. This means the signal is not as clean and the sub cannot be controlled as efficiently, which equals more audible distortion and can hurt/annoy ears.
2. Ported enclosures are generally louder and boomier than sealed enclosures, and tuning of ported enclosures will "make or break" the sound quality. To learn more, read here: http://www.crutchfield.com/S-CmAc90t...nclosures.html


Fixes
1. Run an ohm meter on the sub wiring to see what your ohm rating is.
2. Dump the ported box for properly built sealed enclosure. If you want to save trunk space, you can do something like this: http://www.a4mods.com/index.php?page...tml&category=4
3. If you want to go to the extreme, ditch the ID10 for an IDQ8 or IDQ10 in dual 2 ohms. The ID10 is Image Dynamics "best price per watt" sub. Good for boomy rap, but not super musical. Its meant to handle high wattage at a relatively cheap price. While the ID has good sound for the money, the IDQ is much more musically accurate, is less power hungry, and plays better at lower volumes.

[hoppy6698]

My 2 cents:

OP, you could have other issues with the install (not giving the sub amp a flat, clean signal), but with what facts that you provided, I'm guessing that your that your sub is way over-powering your stock B&O, so your system is not very balanced.

You didn't mention whether you have the dual 2 ohm, or dual 4 ohm ID10?? If you running the dual 4 ohm sub, you are most likely running the amp at 2 ohms, as most installs don't run 8 ohms in car stereo. If this is the case, you could be running more wattage than just the 250 you posted.

Red flags
!. You could be running at 2 ohms. A majority of amps at 2ohms work harder, which cuts your dampening factor in half and increases THD. This means the signal is not as clean and the sub cannot be controlled as efficiently, which equals more audible distortion and can hurt/annoy ears.
2. Ported enclosures are generally louder and boomier than sealed enclosures, and tuning of ported enclosures will "make or break" the sound quality. To learn more, read here: http://www.crutchfield.com/S-CmAc90t...nclosures.html


Fixes
1. Run an ohm meter on the sub wiring to see what your ohm rating is.
2. Dump the ported box for properly built sealed enclosure. If you want to save trunk space, you can do something like this: http://www.a4mods.com/index.php?page...tml&category=4
3. If you want to go to the extreme, ditch the ID10 for an IDQ8 or IDQ10 in dual 2 ohms. The ID10 is Image Dynamics "best price per watt" sub. Good for boomy rap, but not super musical. Its meant to handle high wattage at a relatively cheap price. While the ID has good sound for the money, the IDQ is much more musically accurate, is less power hungry, and plays better at lower volumes.

Thanks for the help in the explanation. The ID10 is D4, so it should be running at 2 ohms, I remember discussing that with the installer. I did buy a sealed box as B520 suggested. After I move the sub over and reconnect it, I need to re-attack the LC2i setup to ensure gains are proper.

However, as you guys noted, I don't think my B&O sub should be still pumping on its own (it still moves when I turn off the JBL amp). I think I will have to live with the 10" sealed until I get out to Seattle in June - then I hope to connect with some trustworthy AZers who may be able to help with some hands-on assistance (Beers on me for any takers!).

[swoardrider]

Thanks for the help in the explanation. The ID10 is D4, so it should be running at 2 ohms, I remember discussing that with the installer. I did buy a sealed box as B520 suggested. After I move the sub over and reconnect it, I need to re-attack the LC2i setup to ensure gains are proper.

However, as you guys noted, I don't think my B&O sub should be still pumping on its own (it still moves when I turn off the JBL amp). I think I will have to live with the 10" sealed until I get out to Seattle in June - then I hope to connect with some trustworthy AZers who may be able to help with some hands-on assistance (Beers on me for any takers!).

Definitely remove the stock sub. The hole it leaves will provide a "port" for the sound to travel into the cab and sound quality will improve.

[V1nny]

As a professional installer, here is my advice:

Buy a prefab 10" sealed box and turn your gains down a bit. Shouldn't cost much for the box. A 10 shouldn't be too boomy, it's likely the box.

as ghetto engineering expert, i would recommend to put an old sweater or similar piece of clothing (older the better) in the subwoofer box port turning it into a sealed box. Buy me some beer with the money saved off the new enclosure purchase.