Ok fellas, I can't do it anymore. This Blazer obviously needs a larger woofer. Even though I could get some eights ported to play lower notes, the box size and reduced power handling may not be worth it. So upon this I am debating on what size and how many to go with next. I'll need some advice since I stayed away from larger woofers for so long (pretty much forgotten how they sound).
I'm shooting for a slight mix of SQ and SPL, but leaning more towards SQ. No doubt I'm going to stick to sealed so I can keep more space and design simple, so don't even suggest any ported.
For power, I will be running my USB-2150 bridged and have about three choices that I'm going with. Just need to know which will be better. First choice is a Dayton 12" DVC from PE. Second, a Dayton RS high output 10" (very small enclosure). Third, a pair of 8 ohm Bostwick HD Pro 10".
The Dayton 10" will fit in about (Qtc=.83/ 52hz) in .23 ft^3 to (Qtc=.7) in .33 ft^3 with a f3 around 51hz.
The Bostwicks with fairly the same f3 results as the Dayton 10" with Qtc at .8 (1 ft^3) and .7 Qtc @ 1.5 ft^3 with about a 2 hz difference. Calculated ft^3 is for both.
The Dayton DVC 12" in about a 1.09 ft^3 with a f3 of 42hz @ Qtc =.83. At Qtc .7= 41hz in 1.66 ft^3.
Clearly the Dayton 10" (also has shorting rings) is impressive with a 12mm xmax and f3 in the ultra small enclosure. Might be quite problematic fitting the giant magnet inside such a small box. The 12 with it's 15mm xmax and low f3 is also impressive, but I don't want like that 1.66ft^3 (like the 1.09 ft^3 better). The Bostwicks are supposedly revered for having low frequency output & definition but, have limited xmax (7.62mm one way each) not to mention I can get them for about half price of the others (wink, wink).
Now for your opinion.....
Replies (12)
swez on 01/25/2006 12:09:28
Ash, since that amp is actually capable of close to 500 Wrms @ 4 ohm loads, a pair of 10's or a stout 12" sub would be a nice addition to your bass engine.
The Alpine SWR-1222D is a fine SQL sub and can give you very good F3 performance in a 0.7 - 1.0 cf sealed box. It's rated at 500 Wrms too.
If you prefer the sound of a pair of 10's, (I do too) The Alpine SWS 1042D's (4+4 DVC's) should be a good match.
Anything with an F3 of above 45 Hz., may not be to your ultimate satisfaction here. Yes, we get some good cabin gain and transfer functions from a large format SUV too.
Just remember 1 key element here... "There is no replacement for displacement" when digging for deep bass performance. We have to move a lot of air in the 40 Hz., range and lower. That means a larger cone area and or long throw coils.
FYI: Long throw coils are hard to work with as they give linearity problems if the motor structure is not potent enough to keep distortion to a minimum. In a sealed box, we have the "air spring" working in our favor.
Comments?
Swez
Ash on 01/26/2006 21:41:00
Very interesting point Swez. I did some calculations and the 12" Dayton will move the most air of all options by a good margin (no "air robbing" double wide surround) and with the lowest f3. Though I like the sound of 10's, in a low Q setup, the Bostwick's small xmax could be a problem with that amp. 250 wrms each on those (not bad).
I always figured that around a 50hz F3 was ideal for most sealed enclosures. The vehicle would do the rest. The lower the F3, the more exaggerated the low end peak. Not sure about this truck though. As long as the 12" is not "sluggish", I would be willing to try it, for I had my eye on it for quite some time. For $90 and 5 year warranty I think it will be hard to beat. Check it out.....
http://www.partsexpress.com/pdf/295-185s.pdf
I read some pretty good reviews on it and found some interesting manufacture info, but that's another story....
swez on 01/26/2006 22:38:02
Well, the only drawback I can see on that sub is the high Vas number. That typically indicates a large box, but will get low with an Fs of 21.7 Hz. Efficiency is not bad either, depending on the frequency they peaked at. (~89dB SPL @1w/1m)
Also noted the .pdf shows a 2.5 cf ported and F3 at 25 Hz. That means a boomy low end in my readings. (Especially when we add cabin gain factors below 50 Hz., and maybe 8-10dB of bass near PTF.
I would say model this one with a sealed box of 0.9 - 1.50 would be a good place to plot this one. It will go lower at 1.25 cf/sub, but may wind up getting a bit sloppy above 1.25 cf?
Comments?
Swez
Ash on 01/27/2006 21:26:10
That's what kept me from jumping on it. The last thing I need is overbearing low end. Just not my style. I modeled it at about Qtc .8 and got decent numbers. Just not sure how much power handling and definitive loss it will be.
On the other hand, the Bostwicks have a excursion limited rating of 250 wrms each in .5cft. In that size enclosure Qtc is .8 with a f3 of 52. Pretty decent match for the USB-2150 as well. Fs for these is pretty good also, 25hz. Vas is okay 2.377cft but, the low .34 Qts keeps box volume down a lot. What catches me most is the unusually high BL of 17.50 compared to the 12's 12.51.......
Though the 12" certainly can move more air, the Bostwicks are not far behind when used as a pair. The musicality is where I'm most concerned. Like you I prefer the sound of 10's, just the 12" makes me curious. I don't want to "boom", however! A hard toss up!
Ash on 01/28/2006 11:16:49
Okay! It's a done deal. I have just ordered the Dayton over the other products. I can live with the 1-1.25cft sealed box. That's relatively small compared to other subs that can reach down to that low of a F3. In the meantime I'll work on a heavy duty enclosure to house the beast.
Thanks for your input Swez........
swez on 01/28/2006 13:55:02
Good deal... am sure you have the skill and such to get what you want with even a pair of plastic trashcan lids for woofers... hehe
May I suggest that when you build your box, use a floating panel(s) that can be adjusted between 1.25 - 0.9 cf/sub chamber. I suspect the 1.25 will be a bit too boomy and sloppy for your tastes. But, as you change internal dimensions with a floating panel(s) system, you can determine what sounds the best for these subs in your vehicle.
Does that compute in your mind's eye?
Swez
Ash on 01/29/2006 07:57:54
I'm gonna shoot right at 1.0 cft+ driver displacement. That's should put it right a Qtc .85, which I think will be a good middle of the road between SQ and SPL. The F3 will be at 43hz, F6 at 34,a minor .43db lift around 90hz should be still definitive with plenty depth. That should definitely be close to the sound that I'm looking for. I never really like .7 Q's unless running heavy mids.
swez on 01/29/2006 11:14:09
Sounds like a plan to me. I too, am leaning away from a Qtc of less than 0.8. Only the very stiff and very robust of subs can do that one well and intuitively, are best under 60 Hz as well. That means, as you said, strong MR/MB extension is needed to fill that gap.
A guy I worked with here, did a 2 x 10" (sealed) Alpine SWR sub design with 0.85 + displacement and loves the punch and solid low bass performance as well. He put them in a Lumina, and then tried them in his Expedition. In both cases, solid lows and tight thump as well.
If the Dayton's are similar, you will probably like these results too.
Good luck and keep us updated OK?
Swez
Ash on 02/2/2006 20:37:08
The "Beast" arrived today, and sadly it's a no-go! I got home from work and patiently waited to open the packaging. After unwrapping the normal carefully P.E. box what did I find?!! A beautiful, beefy sub, missing part of the front mounting gasket with the remainder half attached. Boy was I pissed! I know they always take care of any problems immediatley but, I was really hoping to have this sucker installed over the weekend. Now, it will be another four business days before I receive the replacement and another weekend before I even get to audition it.
As I can tell, this is a hands down, no frills monster. Monstrous double stacked magnets, very stiff nonpressed cone ( I always check by prodding underneath right where the surround attaches to the cone), seemingly durable, thick, foam surround (a bit wider than normal, yet not super wide like others), and a attached rear thin foam gasket. Surprisingly, the rear plate isn't bumped, but that could be due to the length the double mags (112oz) already produce. It is vented however. The cone is somewhat thin for what you would think a 600wrms sub should be. Yet, it is very rigid. A fair amount of kevlar must have been used to get that kind of strength to weight ratio. Nice, big tinsel leads are attached to coils through the cone as usual. To the binding posts, metal tabs extend up towards the front. From these, the leads look to be spade plugged and/or soldered.
In general, a possible good bang for the buck sub with less cosmetic frills. The only con so far is the cheapish paper layered, cork-like topped gasket on the front. All other observations will have to wait until one is finally installed.
swez on 02/3/2006 06:30:54
Sounds like a well made sub here. Just a QC inspection problem from the factory is all. I can see why you were ticked off though. We expect it right, fresh out of the box huh? Not today...
Cork gaskets are pretty old school, but I always like them for rear mounting as they compress well to seal out air gaps. They don't look as nice cosmetically to some, but cork is paintable or we can use black markers to blend them in if desired.
Sorry to hear of your delay. Just look at it as an opportunity to build patience and whet your appetite a little longer. lol
Swez
Ash on 02/10/2006 18:54:05
Okay! She's done! I got the replacement sub within the next 5 business days of receiving the defective one and calling (gotta luv that P.E.!). In the mean time while I waited, I slowly cut and assembled a home for it. I only had a hour each day after work before it got dark, so time was of the essence. I built a sloped rectangular 1.18cft box (minus .10cft for mounting) w/.750" mdf. Installed the sub and checked for leaks as usual. She was good to go.
Before tuning and a little break-in, the bass seemed a little robust with a lack of depth somewhat, crossed over around 75hz (24db). After a little fine tuning and continued playing, you could tell she was starting to get loose. Now, the bass is more smoother with great low end detail without any hint of distortion. It still is able to get quite loud, though I don't see the need. At least the headroom is there for lesser recordings. Even at low volumes, all notes are still there with a nice rolloff. The Dayton 12 DVC has a smooth excursion and with the box/sub Q set around .8 it exhibits a excellent medium to play most types of music accurately. Not to mention, the bass isn't overbearing at all, but it is demanding a beefier midbass than the 5.25" to blend with it. That will be the next project and very soon. I'm very happy with the Dayton! $102 shipped with a 5 year warranty was a excellent deal!
Last phase will be a added baffle to recess the driver and then some interior matching carpeting.
Thanks for the input!
swez on 02/10/2006 22:23:54
Well done there Ash. Now we have an aternate to the more expensive subs out there, to add to the mix. (like we needed more) hehe
I read you article as promised. It's good on the overview side, but well above the newbie's comprehension and has some minor gaps for the more experienced DIY.
FYI: Suggest you pick the "audience" to address the topic in details they need most.
Other than that, some very good pointers for the beginner and advanced players. This is one of the hardest parts of writing any DIY'er guide. "What audience am I trying to reach"? Since you have a solid backround in the deeper issues, it's harder to bring it to the bottom shelf for newbie consumption. A Part IIIII follow up might be helpful to new readers and advanced ones as well.
Comments?
Swez
I'm shooting for a slight mix of SQ and SPL, but leaning more towards SQ. No doubt I'm going to stick to sealed so I can keep more space and design simple, so don't even suggest any ported.
For power, I will be running my USB-2150 bridged and have about three choices that I'm going with. Just need to know which will be better. First choice is a Dayton 12" DVC from PE. Second, a Dayton RS high output 10" (very small enclosure). Third, a pair of 8 ohm Bostwick HD Pro 10".
The Dayton 10" will fit in about (Qtc=.83/ 52hz) in .23 ft^3 to (Qtc=.7) in .33 ft^3 with a f3 around 51hz.
The Bostwicks with fairly the same f3 results as the Dayton 10" with Qtc at .8 (1 ft^3) and .7 Qtc @ 1.5 ft^3 with about a 2 hz difference. Calculated ft^3 is for both.
The Dayton DVC 12" in about a 1.09 ft^3 with a f3 of 42hz @ Qtc =.83. At Qtc .7= 41hz in 1.66 ft^3.
Clearly the Dayton 10" (also has shorting rings) is impressive with a 12mm xmax and f3 in the ultra small enclosure. Might be quite problematic fitting the giant magnet inside such a small box. The 12 with it's 15mm xmax and low f3 is also impressive, but I don't want like that 1.66ft^3 (like the 1.09 ft^3 better). The Bostwicks are supposedly revered for having low frequency output & definition but, have limited xmax (7.62mm one way each) not to mention I can get them for about half price of the others (wink, wink).
Now for your opinion.....
Replies (12)
swez on 01/25/2006 12:09:28
Ash, since that amp is actually capable of close to 500 Wrms @ 4 ohm loads, a pair of 10's or a stout 12" sub would be a nice addition to your bass engine.
The Alpine SWR-1222D is a fine SQL sub and can give you very good F3 performance in a 0.7 - 1.0 cf sealed box. It's rated at 500 Wrms too.
If you prefer the sound of a pair of 10's, (I do too) The Alpine SWS 1042D's (4+4 DVC's) should be a good match.
Anything with an F3 of above 45 Hz., may not be to your ultimate satisfaction here. Yes, we get some good cabin gain and transfer functions from a large format SUV too.
Just remember 1 key element here... "There is no replacement for displacement" when digging for deep bass performance. We have to move a lot of air in the 40 Hz., range and lower. That means a larger cone area and or long throw coils.
FYI: Long throw coils are hard to work with as they give linearity problems if the motor structure is not potent enough to keep distortion to a minimum. In a sealed box, we have the "air spring" working in our favor.
Comments?
Swez
Ash on 01/26/2006 21:41:00
Very interesting point Swez. I did some calculations and the 12" Dayton will move the most air of all options by a good margin (no "air robbing" double wide surround) and with the lowest f3. Though I like the sound of 10's, in a low Q setup, the Bostwick's small xmax could be a problem with that amp. 250 wrms each on those (not bad).
I always figured that around a 50hz F3 was ideal for most sealed enclosures. The vehicle would do the rest. The lower the F3, the more exaggerated the low end peak. Not sure about this truck though. As long as the 12" is not "sluggish", I would be willing to try it, for I had my eye on it for quite some time. For $90 and 5 year warranty I think it will be hard to beat. Check it out.....
http://www.partsexpress.com/pdf/295-185s.pdf
I read some pretty good reviews on it and found some interesting manufacture info, but that's another story....
swez on 01/26/2006 22:38:02
Well, the only drawback I can see on that sub is the high Vas number. That typically indicates a large box, but will get low with an Fs of 21.7 Hz. Efficiency is not bad either, depending on the frequency they peaked at. (~89dB SPL @1w/1m)
Also noted the .pdf shows a 2.5 cf ported and F3 at 25 Hz. That means a boomy low end in my readings. (Especially when we add cabin gain factors below 50 Hz., and maybe 8-10dB of bass near PTF.
I would say model this one with a sealed box of 0.9 - 1.50 would be a good place to plot this one. It will go lower at 1.25 cf/sub, but may wind up getting a bit sloppy above 1.25 cf?
Comments?
Swez
Ash on 01/27/2006 21:26:10
That's what kept me from jumping on it. The last thing I need is overbearing low end. Just not my style. I modeled it at about Qtc .8 and got decent numbers. Just not sure how much power handling and definitive loss it will be.
On the other hand, the Bostwicks have a excursion limited rating of 250 wrms each in .5cft. In that size enclosure Qtc is .8 with a f3 of 52. Pretty decent match for the USB-2150 as well. Fs for these is pretty good also, 25hz. Vas is okay 2.377cft but, the low .34 Qts keeps box volume down a lot. What catches me most is the unusually high BL of 17.50 compared to the 12's 12.51.......
Though the 12" certainly can move more air, the Bostwicks are not far behind when used as a pair. The musicality is where I'm most concerned. Like you I prefer the sound of 10's, just the 12" makes me curious. I don't want to "boom", however! A hard toss up!
Ash on 01/28/2006 11:16:49
Okay! It's a done deal. I have just ordered the Dayton over the other products. I can live with the 1-1.25cft sealed box. That's relatively small compared to other subs that can reach down to that low of a F3. In the meantime I'll work on a heavy duty enclosure to house the beast.
Thanks for your input Swez........
swez on 01/28/2006 13:55:02
Good deal... am sure you have the skill and such to get what you want with even a pair of plastic trashcan lids for woofers... hehe
May I suggest that when you build your box, use a floating panel(s) that can be adjusted between 1.25 - 0.9 cf/sub chamber. I suspect the 1.25 will be a bit too boomy and sloppy for your tastes. But, as you change internal dimensions with a floating panel(s) system, you can determine what sounds the best for these subs in your vehicle.
Does that compute in your mind's eye?
Swez
Ash on 01/29/2006 07:57:54
I'm gonna shoot right at 1.0 cft+ driver displacement. That's should put it right a Qtc .85, which I think will be a good middle of the road between SQ and SPL. The F3 will be at 43hz, F6 at 34,a minor .43db lift around 90hz should be still definitive with plenty depth. That should definitely be close to the sound that I'm looking for. I never really like .7 Q's unless running heavy mids.
swez on 01/29/2006 11:14:09
Sounds like a plan to me. I too, am leaning away from a Qtc of less than 0.8. Only the very stiff and very robust of subs can do that one well and intuitively, are best under 60 Hz as well. That means, as you said, strong MR/MB extension is needed to fill that gap.
A guy I worked with here, did a 2 x 10" (sealed) Alpine SWR sub design with 0.85 + displacement and loves the punch and solid low bass performance as well. He put them in a Lumina, and then tried them in his Expedition. In both cases, solid lows and tight thump as well.
If the Dayton's are similar, you will probably like these results too.
Good luck and keep us updated OK?
Swez
Ash on 02/2/2006 20:37:08
The "Beast" arrived today, and sadly it's a no-go! I got home from work and patiently waited to open the packaging. After unwrapping the normal carefully P.E. box what did I find?!! A beautiful, beefy sub, missing part of the front mounting gasket with the remainder half attached. Boy was I pissed! I know they always take care of any problems immediatley but, I was really hoping to have this sucker installed over the weekend. Now, it will be another four business days before I receive the replacement and another weekend before I even get to audition it.
As I can tell, this is a hands down, no frills monster. Monstrous double stacked magnets, very stiff nonpressed cone ( I always check by prodding underneath right where the surround attaches to the cone), seemingly durable, thick, foam surround (a bit wider than normal, yet not super wide like others), and a attached rear thin foam gasket. Surprisingly, the rear plate isn't bumped, but that could be due to the length the double mags (112oz) already produce. It is vented however. The cone is somewhat thin for what you would think a 600wrms sub should be. Yet, it is very rigid. A fair amount of kevlar must have been used to get that kind of strength to weight ratio. Nice, big tinsel leads are attached to coils through the cone as usual. To the binding posts, metal tabs extend up towards the front. From these, the leads look to be spade plugged and/or soldered.
In general, a possible good bang for the buck sub with less cosmetic frills. The only con so far is the cheapish paper layered, cork-like topped gasket on the front. All other observations will have to wait until one is finally installed.
swez on 02/3/2006 06:30:54
Sounds like a well made sub here. Just a QC inspection problem from the factory is all. I can see why you were ticked off though. We expect it right, fresh out of the box huh? Not today...
Cork gaskets are pretty old school, but I always like them for rear mounting as they compress well to seal out air gaps. They don't look as nice cosmetically to some, but cork is paintable or we can use black markers to blend them in if desired.
Sorry to hear of your delay. Just look at it as an opportunity to build patience and whet your appetite a little longer. lol
Swez
Ash on 02/10/2006 18:54:05
Okay! She's done! I got the replacement sub within the next 5 business days of receiving the defective one and calling (gotta luv that P.E.!). In the mean time while I waited, I slowly cut and assembled a home for it. I only had a hour each day after work before it got dark, so time was of the essence. I built a sloped rectangular 1.18cft box (minus .10cft for mounting) w/.750" mdf. Installed the sub and checked for leaks as usual. She was good to go.
Before tuning and a little break-in, the bass seemed a little robust with a lack of depth somewhat, crossed over around 75hz (24db). After a little fine tuning and continued playing, you could tell she was starting to get loose. Now, the bass is more smoother with great low end detail without any hint of distortion. It still is able to get quite loud, though I don't see the need. At least the headroom is there for lesser recordings. Even at low volumes, all notes are still there with a nice rolloff. The Dayton 12 DVC has a smooth excursion and with the box/sub Q set around .8 it exhibits a excellent medium to play most types of music accurately. Not to mention, the bass isn't overbearing at all, but it is demanding a beefier midbass than the 5.25" to blend with it. That will be the next project and very soon. I'm very happy with the Dayton! $102 shipped with a 5 year warranty was a excellent deal!
Last phase will be a added baffle to recess the driver and then some interior matching carpeting.
Thanks for the input!
swez on 02/10/2006 22:23:54
Well done there Ash. Now we have an aternate to the more expensive subs out there, to add to the mix. (like we needed more) hehe
I read you article as promised. It's good on the overview side, but well above the newbie's comprehension and has some minor gaps for the more experienced DIY.
FYI: Suggest you pick the "audience" to address the topic in details they need most.
Other than that, some very good pointers for the beginner and advanced players. This is one of the hardest parts of writing any DIY'er guide. "What audience am I trying to reach"? Since you have a solid backround in the deeper issues, it's harder to bring it to the bottom shelf for newbie consumption. A Part IIIII follow up might be helpful to new readers and advanced ones as well.
Comments?
Swez
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