jonathanengr1 10+ year member
Member
Okay... everyone be patient with me here. It's been a while since I was dabbling in car audio and subs!
I wanted to add some low end to a boat stereo, and wanted to keep my purchases local. Now--back in my day about the only options were MTX, Rockford Fosgate and a few others, but now there seems to be hundreds to choose from. I went to a local car stereo shop, told them what I wanted to do and asked them for the best sub for the job. They all agreed that the entry-level digital design 500-series subs would do well (good bass, relatively inexpensive, and not ear-splitting loud), so I bought two 10" subs in an enclosure they built to fit in an area in my boat. They are driven by the sub channel of a Kicker ZXM 700.5 marine amp at a 2 ohm load (420w).
Well, they certainly added low end. These things are extremely potent--almost too much. However, the one thing I really don't care for is the way the subs sound... especially with songs that are bass-heavy. The bass sounds great for my 80's collection of songs, but any of the newer songs I like make the bass go haywire. It. Sounds. Horrible. It vibrates and sounds like an incredibly fast, deep machine gun rat-a-tat-tatting. Sort-of like the vibratory sound you hear of someone showing off their subs on youtube (a staccato hum instead of a smooth, deep tone).
Now--the box is ported--and I've never owned a ported box before. I always owned sealed enclosures and *loved* the way they sound (was a big RF fan back in the day), but then-again, that was during the 80's, and my 80's music sounded just fine on these subs. Anyway, here's my predicament.
First and foremost, I own these subs... they both got scratched when I put the box into the area on my boat, so no returns. Thus, although I'm sure there are lots of suggestions on other subs out there (I can imagine how lively a conversation that would be these days with all of the choices!), for now let's consider only the DD subs I own.
Okay... so I called the DD factory to ask about possibly separating the subs and putting them into two separate sealed enclosures, and asked what size sealed box I'd need. I couldn't see the guy on the other end of the phone, but I'm sure his expression was one of shock and horror. You'd think I was the only human being on earth to have ever asked this question (and maybe I am). He was very polite while he stuttered and stumbled the words "the same size box as the ported enclosure--1.5 cf per sub". He then added "we really don't endorse sealed boxes with our subs". I then went on to ask about the box I had... basically, the guys I bought this from had a ported box made for a single DD 10" sub (1.5 cf with a 24 square-inch port) and they said they could simply cut a hole for a second sub. Sounded good to me. However, DD recommends 1.5 cf PER 10" sub. So... here are my questions:
1) I know that DD subs are designed from the ground up for ported enclosures, but would they still sound good and/or pound in a sealed enclosure? Based on a Qts of 0.405 they seem to be in the realm of sealed boxes (I found this info in a forum post I Googled... still have no idea what Qts means... just that 0.4 or under tends to be good for ported, 0.4 to 0.7 is good for sealed and above 0.7 is free-air.... does this sound right?) Any idea of the size of the sealed enclosure I should build? When the guy said "the same size as ported" that threw me for a loop. Usually speakers that can be used in either a sealed or ported application require a much smaller sealed enclosure, and some subs have a very narrow recommended range of box sizes. I don't want to make a sealed box that will sound terrible or have no bass.
2) If everyone thinks I should go ported, was the box design sold to me inadequate? I mean--I really need 3 cf based on DD's specs, so could this bad sound be due to the too-small box? I've been researching the internet (dangerous, I know!) on tuning ported boxes, and many people recommend tuning low (30 hz ideally but no higher than 35 hz) if you want a more flat bass response like a sealed box. I stumbled onto a website to help tune a sub based on box size, etc., and have been tinkering with calcs for rectangular and round ports to tune the box down to 30 hz (looks like for a 1.5 cf box I'll need a 21-inch long 1.75 inch by 10 inch rectangular port or a 5 inch long 2" diameter round port... can anyone verify this? Any preference on port type? I know round ports can make more noise, but their easier to tune and are more compact. I assume flared is best to reduce noise). Again--should I do 1.5 cf per sub (I'd have to separate them to do this). I could still wire them in parallel to get the 2-ohm load.
Anyway, I know everyone has their own tastes, but I'm just not okay with my subs sounding like a really deep buzzer (again--this only happens on the really heavy, deep-bass songs). I want a good, distinct tone to each note that is a constant sound--nothing staccato. I would really, really appreciate any input you guys could give me. I'm a pretty handy finishing carpenter, so I can build whatever might be needed enclosure-wise.
Thanks so much!!
I wanted to add some low end to a boat stereo, and wanted to keep my purchases local. Now--back in my day about the only options were MTX, Rockford Fosgate and a few others, but now there seems to be hundreds to choose from. I went to a local car stereo shop, told them what I wanted to do and asked them for the best sub for the job. They all agreed that the entry-level digital design 500-series subs would do well (good bass, relatively inexpensive, and not ear-splitting loud), so I bought two 10" subs in an enclosure they built to fit in an area in my boat. They are driven by the sub channel of a Kicker ZXM 700.5 marine amp at a 2 ohm load (420w).
Well, they certainly added low end. These things are extremely potent--almost too much. However, the one thing I really don't care for is the way the subs sound... especially with songs that are bass-heavy. The bass sounds great for my 80's collection of songs, but any of the newer songs I like make the bass go haywire. It. Sounds. Horrible. It vibrates and sounds like an incredibly fast, deep machine gun rat-a-tat-tatting. Sort-of like the vibratory sound you hear of someone showing off their subs on youtube (a staccato hum instead of a smooth, deep tone).
Now--the box is ported--and I've never owned a ported box before. I always owned sealed enclosures and *loved* the way they sound (was a big RF fan back in the day), but then-again, that was during the 80's, and my 80's music sounded just fine on these subs. Anyway, here's my predicament.
First and foremost, I own these subs... they both got scratched when I put the box into the area on my boat, so no returns. Thus, although I'm sure there are lots of suggestions on other subs out there (I can imagine how lively a conversation that would be these days with all of the choices!), for now let's consider only the DD subs I own.
Okay... so I called the DD factory to ask about possibly separating the subs and putting them into two separate sealed enclosures, and asked what size sealed box I'd need. I couldn't see the guy on the other end of the phone, but I'm sure his expression was one of shock and horror. You'd think I was the only human being on earth to have ever asked this question (and maybe I am). He was very polite while he stuttered and stumbled the words "the same size box as the ported enclosure--1.5 cf per sub". He then added "we really don't endorse sealed boxes with our subs". I then went on to ask about the box I had... basically, the guys I bought this from had a ported box made for a single DD 10" sub (1.5 cf with a 24 square-inch port) and they said they could simply cut a hole for a second sub. Sounded good to me. However, DD recommends 1.5 cf PER 10" sub. So... here are my questions:
1) I know that DD subs are designed from the ground up for ported enclosures, but would they still sound good and/or pound in a sealed enclosure? Based on a Qts of 0.405 they seem to be in the realm of sealed boxes (I found this info in a forum post I Googled... still have no idea what Qts means... just that 0.4 or under tends to be good for ported, 0.4 to 0.7 is good for sealed and above 0.7 is free-air.... does this sound right?) Any idea of the size of the sealed enclosure I should build? When the guy said "the same size as ported" that threw me for a loop. Usually speakers that can be used in either a sealed or ported application require a much smaller sealed enclosure, and some subs have a very narrow recommended range of box sizes. I don't want to make a sealed box that will sound terrible or have no bass.
2) If everyone thinks I should go ported, was the box design sold to me inadequate? I mean--I really need 3 cf based on DD's specs, so could this bad sound be due to the too-small box? I've been researching the internet (dangerous, I know!) on tuning ported boxes, and many people recommend tuning low (30 hz ideally but no higher than 35 hz) if you want a more flat bass response like a sealed box. I stumbled onto a website to help tune a sub based on box size, etc., and have been tinkering with calcs for rectangular and round ports to tune the box down to 30 hz (looks like for a 1.5 cf box I'll need a 21-inch long 1.75 inch by 10 inch rectangular port or a 5 inch long 2" diameter round port... can anyone verify this? Any preference on port type? I know round ports can make more noise, but their easier to tune and are more compact. I assume flared is best to reduce noise). Again--should I do 1.5 cf per sub (I'd have to separate them to do this). I could still wire them in parallel to get the 2-ohm load.
Anyway, I know everyone has their own tastes, but I'm just not okay with my subs sounding like a really deep buzzer (again--this only happens on the really heavy, deep-bass songs). I want a good, distinct tone to each note that is a constant sound--nothing staccato. I would really, really appreciate any input you guys could give me. I'm a pretty handy finishing carpenter, so I can build whatever might be needed enclosure-wise.
Thanks so much!!
