SR124-DVC Enclosure

Remyngton
Remyngton Posts: 18
edited January 2008 in Car Subwoofer Talk
Hello,

I purchased a single SR124-DVC for my RX-8 and it is still on back order. I'm looking for the most accurate bass reproduction possible and I have an Alpine V12 600W RMS at 2 ohms Mono amp (rated at 655W RMS) to push it. Right now it is on back order from the company, so I have more time to look into the box I would like to get. Right now I am set on a 1.00 cubic foot sealed box. Not wanting to build my own to get the extra .02 cubic feet to make it exactly what Polk reccomends. I just want to make sure that this is the correct size according to the manufacturer that is reccomended. I am taking the volume of the sub into account, is this correct?
Post edited by Remyngton on
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Comments

  • najahaja
    najahaja Posts: 32
    edited October 2007
    the recomnded specs from the polk website is 1.2 cubic feet. Your box would effectively be 0.2 cubic feet smaller. Not sure exactly how this would effect the sound, but it is about 17% smaller than recomended.

    And yes, the size on the website is taking the displacement into account.
  • Remyngton
    Remyngton Posts: 18
    edited October 2007
    Are we looking at the same sub? Where did you get 1.2 cubic feet from? According to the PDF manual it says .88 cubic feet plus .14 cubic feet for the sub displacement which would make it 1.02 cubic feet total. I picked a 1.0 cubic foot box, so am I looking at this wrong? Someone correct me if this is not correct.
  • MacLeod
    MacLeod Posts: 14,358
    edited October 2007
    http://www.polkaudio.com/caraudio/subbox/subbox_plan.php?id=96&mesurements=standard

    The SR124 us spec'd for a 1.2 ft3 box.

    Using a 1 ft3 box will work but you may have a response hump in the lower sub range but it shouldnt be too bad.
    polkaudio sound quality competitor since 2005
    MECA SQ Rookie of the Year 06 ~ MECA State Champ 06,07,08,11 ~ MECA World Finals 2nd place 06,07,08,09
    08 Car Audio Nationals 1st ~ 07 N Georgia Nationals 1st ~ 06 Carl Casper Nationals 1st ~ USACi 05 Southeast AutumnFest 1st

    polkaudio SR6500 --- polkaudio MM1040 x2 -- Pioneer P99 -- Rockford Fosgate P1000X5D
  • Installer4life
    Installer4life Posts: 256
    edited October 2007
    According to Polk the 1.2 cubic ft. box will yield the most acurate frequency response. A "Q' OF .707 which is what you want when trying to achieve accurate bass response. I am going to use the same internal volume on a couple of SR124DVC's so if you beat me to it let me know how it sounds. If your box is a little smaller you bass will be tighter and lose a little low bass extension. Since the RX8 is a hatchback your transfer function is going to help you a lot. Try the smaller box it might work out great.
  • Remyngton
    Remyngton Posts: 18
    edited October 2007
    MacLeod wrote: »
    http://www.polkaudio.com/caraudio/subbox/subbox_plan.php?id=96&mesurements=standard

    The SR124 us spec'd for a 1.2 ft3 box.

    Using a 1 ft3 box will work but you may have a response hump in the lower sub range but it shouldnt be too bad.

    Can I use some polyfill in the 1.00 ft3 box to get more displacement out of it?
  • JDMJim
    JDMJim Posts: 2
    edited October 2007
    RX-8 is not a hatchback. we have put in a SR124DVC and we've gone thru two subs. I think the box may be a little too small according to techs.
  • Remyngton
    Remyngton Posts: 18
    edited October 2007
    JDMJim wrote: »
    RX-8 is not a hatchback. we have put in a SR124DVC and we've gone thru two subs. I think the box may be a little too small according to techs.

    Correct, RX-8 is not a hatchback.

    What do you mean you have gone through two subs?
  • MacLeod
    MacLeod Posts: 14,358
    edited October 2007
    Remyngton wrote: »
    Can I use some polyfill in the 1.00 ft3 box to get more displacement out of it?

    Yes. But its no substitute for a bigger box.
    polkaudio sound quality competitor since 2005
    MECA SQ Rookie of the Year 06 ~ MECA State Champ 06,07,08,11 ~ MECA World Finals 2nd place 06,07,08,09
    08 Car Audio Nationals 1st ~ 07 N Georgia Nationals 1st ~ 06 Carl Casper Nationals 1st ~ USACi 05 Southeast AutumnFest 1st

    polkaudio SR6500 --- polkaudio MM1040 x2 -- Pioneer P99 -- Rockford Fosgate P1000X5D
  • Remyngton
    Remyngton Posts: 18
    edited October 2007
    MacLeod wrote: »
    http://www.polkaudio.com/caraudio/subbox/subbox_plan.php?id=96&mesurements=standard

    The SR124 us spec'd for a 1.2 ft3 box.

    Using a 1 ft3 box will work but you may have a response hump in the lower sub range but it shouldnt be too bad.

    When you say low, what frequency range are you talking about? below 40Hz?
  • Installer4life
    Installer4life Posts: 256
    edited October 2007
    Remyngton wrote: »
    Can I use some polyfill in the 1.00 ft3 box to get more displacement out of it?

    ARe you trying to use a prefab enclosure? If you are I would not recommend it. Have one built it will be worth the difference.
  • MacLeod
    MacLeod Posts: 14,358
    edited October 2007
    Remyngton wrote: »
    When you say low, what frequency range are you talking about? below 40Hz?

    Yeah, thats usually the range it happens. However some people like the sound of this so its not necessarily a bad thing. Hell most amps with bass boost have it set at 40 Hz.
    polkaudio sound quality competitor since 2005
    MECA SQ Rookie of the Year 06 ~ MECA State Champ 06,07,08,11 ~ MECA World Finals 2nd place 06,07,08,09
    08 Car Audio Nationals 1st ~ 07 N Georgia Nationals 1st ~ 06 Carl Casper Nationals 1st ~ USACi 05 Southeast AutumnFest 1st

    polkaudio SR6500 --- polkaudio MM1040 x2 -- Pioneer P99 -- Rockford Fosgate P1000X5D
  • JDMJim
    JDMJim Posts: 2
    edited October 2007
    Remyngton wrote: »
    Can I use some polyfill in the 1.00 ft3 box to get more displacement out of it?

    smoked two 124's with the 1.02 box
  • 1996blackmax
    1996blackmax Posts: 2,436
    edited October 2007
    I've used subs in smaller than recommended boxes with good results. I used some polyfill. I never blew a sub that way though.

    ARe you trying to use a prefab enclosure? If you are I would not recommend it. Have one built it will be worth the difference.

    It all depends...... if the prefab enclosure is proplerly made, properly sealed, and if it's within the woofer's recommended specs there should not be an issue. I am using one right now, and have been using this same one through 3 different subs. One of them being a Soundsplinter RL-P (weighs 35lbs) being fed 1100 watts RMS from an Arc Audio 1500-XXK.
    Alpine: CDA-7949
    Alpine: PXA-H600
    Alpine: CHA-S624, KCA-420i, KCA-410C
    Rainbow: CS 265 Profi Phase Plug / SL 165
    ARC Audio: 4150-XXK / 1500v1-XXK
    JL Audio: 10W6v2 (x2)
    KnuKonceptz
    Second Skin
  • Remyngton
    Remyngton Posts: 18
    edited October 2007
    JDMJim wrote: »
    smoked two 124's with the 1.02 box

    How much power were you feeding them?
  • rz22g
    rz22g Posts: 70
    edited October 2007
    Ok Im about to build a dual sealed for my two SR124 DVC's so what was the final word? Manual says final volume of .88 and site says final volume of 1.20.
  • Remyngton
    Remyngton Posts: 18
    edited October 2007
    rz22g wrote: »
    Ok Im about to build a dual sealed for my two SR124 DVC's so what was the final word? Manual says final volume of .88 and site says final volume of 1.20.

    I am going to get the 1.00 ft3 box, to save on trunk space in my RX-8, I'll let you know how I like it with and without polyfill. I am still waiting on the order to come in. I don't know if anyone has dealt with sonicelectronix.com, but I have been waiting a month for 1 of these speakers, it's still on backorder. Maybe they are still looking for a car to steal it out of. :rolleyes:
  • rz22g
    rz22g Posts: 70
    edited October 2007
    Remyngton wrote: »
    I am going to get the 1.00 ft3 box, to save on trunk space in my RX-8, I'll let you know how I like it with and without polyfill. I am still waiting on the order to come in. I don't know if anyone has dealt with sonicelectronix.com, but I have been waiting a month for 1 of these speakers, it's still on backorder. Maybe they are still looking for a car to steal it out of. :rolleyes:

    http://www.resellerratings.com and then in the store field type in the name of the online store you want to check up on. This site is great if you use it BEFORE you use the store. I have not checked lately but I think I remember alot of negative comments... mostly about items never being shipped out.

    If you end up going another route, go to here http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=150169150825&ssPageName=STRK:MEWA:IT&ih=005 That is the link to my purchase so it shows up as ended so you might have to browse around and find the actual listing.

    Im not sure what you were paying but I know these are legit because I have already received my 2 from them.
  • rz22g
    rz22g Posts: 70
    edited October 2007
    Disregard below question. I figured out that I cannot get the volume needed while also keeping the back of the subs from touching my cargo cover.


    Im throwing around the idea of reverse mounting the SR124's. My plan is to make two shallow enclosures and get my volume from the width and height. The top of each enclosure would actually meet and become a false floor in the back of my TC.

    Question is... what is the minimum depth I can go for the enclosure so that I have not concern of the sub smacking the inside bottom of the enclosure? Also will having a very shallow enclosure, although it may be the correct volume, have an impact on sound as compared to a more traditional shape?
  • Remyngton
    Remyngton Posts: 18
    edited October 2007
    rz22g wrote: »
    Disregard below question. I figured out that I cannot get the volume needed while also keeping the back of the subs from touching my cargo cover.


    Im throwing around the idea of reverse mounting the SR124's. My plan is to make two shallow enclosures and get my volume from the width and height. The top of each enclosure would actually meet and become a false floor in the back of my TC.

    Question is... what is the minimum depth I can go for the enclosure so that I have not concern of the sub smacking the inside bottom of the enclosure? Also will having a very shallow enclosure, although it may be the correct volume, have an impact on sound as compared to a more traditional shape?

    The mounting depth is 7-3/5", so I would give it at least 8" to be on the safe side.
    As far as the box shape, from what I understand any shape with the same volume will sound the same as long as it is not perfectly square or perfectly round.

    I just saw that you edited that, disregard.
  • rz22g
    rz22g Posts: 70
    edited October 2007
    Remyngton wrote: »
    The mounting depth is 7-3/5", so I would give it at least 8" to be on the safe side.
    As far as the box shape, from what I understand any shape with the same volume will sound the same as long as it is not perfectly square or perfectly round.

    I just saw that you edited that, disregard.

    Yep I ditched the idea because in order to keep the back of the subs from hitting the cargo cover in my car, and keep the enclosure from sticking above the rear sill, it needed to be 4 inches high on one end and 2 on the other and that would not give me the volume I needed.

    I ended up building a wedge shape. I made the internal volume (without sub) 1.34. This way I can mounting normally and get 1.20 but later I will reverse mount the subs but put a piece of wood that is .14 in volume in each chamber.

    It will be done today but Im going to stick to the break in recommendation so I cant really push it to test the sound yet.
  • Remyngton
    Remyngton Posts: 18
    edited October 2007
    rz22g wrote: »
    Yep I ditched the idea because in order to keep the back of the subs from hitting the cargo cover in my car, and keep the enclosure from sticking above the rear sill, it needed to be 4 inches high on one end and 2 on the other and that would not give me the volume I needed.

    I ended up building a wedge shape. I made the internal volume (without sub) 1.34. This way I can mounting normally and get 1.20 but later I will reverse mount the subs but put a piece of wood that is .14 in volume in each chamber.

    It will be done today but Im going to stick to the break in recommendation so I cant really push it to test the sound yet.

    I want to know how it sounds when you get it done. What type of car do you have?

    Sonicelectronix has finally got the SR124-DVC in stock, so hopefully I will get it next week. I'm still going with the 1.00 to save my trunk space. I don't even know if that is going to fit where I want it yet. I will have to use polyfill, but I REALLY want to hear the difference in an identical setup between the 1.00 and 1.20 enclosures. I'm sure both will sound great, but of course, I want the better of the two.
  • rz22g
    rz22g Posts: 70
    edited October 2007
    Remyngton wrote: »
    I want to know how it sounds when you get it done. What type of car do you have?

    Sonicelectronix has finally got the SR124-DVC in stock, so hopefully I will get it next week. I'm still going with the 1.00 to save my trunk space. I don't even know if that is going to fit where I want it yet. I will have to use polyfill, but I REALLY want to hear the difference in an identical setup between the 1.00 and 1.20 enclosures. I'm sure both will sound great, but of course, I want the better of the two.

    I have a Scion TC. I finished my enclosure for the most part. It came out heavier than I would have liked at just over 105 pounds with the subs. I still need to seal and cover. Im looking for a silicone alternative... something I can go ahead and stick the subs in the same day.
  • rz22g
    rz22g Posts: 70
    edited October 2007
    Still looking for an alternative to silicone for sealing my enclosure. Any ideas?
  • MacLeod
    MacLeod Posts: 14,358
    edited October 2007
    Why dont you want to use silicone. You can buy a tube of sealeant from Home Depot for $2, itll last forever and work like a charm.
    polkaudio sound quality competitor since 2005
    MECA SQ Rookie of the Year 06 ~ MECA State Champ 06,07,08,11 ~ MECA World Finals 2nd place 06,07,08,09
    08 Car Audio Nationals 1st ~ 07 N Georgia Nationals 1st ~ 06 Carl Casper Nationals 1st ~ USACi 05 Southeast AutumnFest 1st

    polkaudio SR6500 --- polkaudio MM1040 x2 -- Pioneer P99 -- Rockford Fosgate P1000X5D
  • rz22g
    rz22g Posts: 70
    edited October 2007
    Read a few places that the fumes given off the first few days can destroy the old foam type surround and weaken the material used for surround on newer subs. I was looking for something I could use immediately rather than have to let the enclosure sit for a few days.
  • MacLeod
    MacLeod Posts: 14,358
    edited October 2007
    I cant remember exactly what brand I used but I let it sit overnight and once it cured I slapped my sub in there and it worked fine. Went 2 years with the first enclosure and have had it in the new one for a year now with no problems.
    polkaudio sound quality competitor since 2005
    MECA SQ Rookie of the Year 06 ~ MECA State Champ 06,07,08,11 ~ MECA World Finals 2nd place 06,07,08,09
    08 Car Audio Nationals 1st ~ 07 N Georgia Nationals 1st ~ 06 Carl Casper Nationals 1st ~ USACi 05 Southeast AutumnFest 1st

    polkaudio SR6500 --- polkaudio MM1040 x2 -- Pioneer P99 -- Rockford Fosgate P1000X5D
  • Greg Peters
    Greg Peters Posts: 605
    edited October 2007
    rz22g wrote: »
    Read a few places that the fumes given off the first few days can destroy the old foam type surround and weaken the material used for surround on newer subs. I was looking for something I could use immediately rather than have to let the enclosure sit for a few days.

    IIRC it's acetic acid fumes that silicone gives off during the curing process. Not good for more than just the sub's foam surrounds (it's corrosive), but the good news is if you seal up your enclosure with silicone today, by tomorrow you'll be pretty much good to go for mounting your subs- most of the fumes gas out within the first 24 hours after application. Anything released by the product after that should be negligible. Lighter applications cure faster than a single heavy one.

    I've built up multiple layers of Weldbond on all seams inside the enclosure instead of using silicone, but the bad news is that glue takes much longer to cure than the standard sealant- the good news is it takes a hammer and chisel to penetrate the seams after curing. A more thorough method still would be to swish some fiberglass resin over all internal seams inside, but that would take longer than silicone to fully cure, and give off even more (toxic) fumes in the process.

    Some silicone (and a day or two for curing) is a small price to pay for an airtight enclosure, and it's more than durable enough for our purposes.
  • rz22g
    rz22g Posts: 70
    edited October 2007
    Thanks for the help. I posted in another thread about running both C500.1 subs off of one remote bass control and a couple of people responded that I should try it. Any thoughts on that..

    Also I set my box up to use as normal sub mount initially but later I am going to reverse mount and add the appropriate size piece of wood inside to compensate for the sub displacement. When reverse mounting is there any decreased in performance? Also should the polarity be reversed?
  • Remyngton
    Remyngton Posts: 18
    edited October 2007
    Question:
    Would reversing the subwoofer in the 1.00 ft3 enclosure be the same as having a bigger enclosure? It is too early in the morning to do the math, but it would put it close to 1.20 ft3.
  • 1996blackmax
    1996blackmax Posts: 2,436
    edited October 2007
    Yes....whatever the sub's displacement is will be what the enclosure will gain in volume.
    Alpine: CDA-7949
    Alpine: PXA-H600
    Alpine: CHA-S624, KCA-420i, KCA-410C
    Rainbow: CS 265 Profi Phase Plug / SL 165
    ARC Audio: 4150-XXK / 1500v1-XXK
    JL Audio: 10W6v2 (x2)
    KnuKonceptz
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