Drilling hole in Subwoofer

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AgaBoogaBoo

Lifer
Feb 16, 2003
26,108
5
81
Originally posted by: Excelsior
Originally posted by: AgaBoogaBoo
Originally posted by: Excelsior
Ok, this whole 'sealed = tight, responsive, clean' and 'ported =boomy, slow' bit is ridiculous. At best it is some gross oversimplification based off peoples experiences with cheap equipment.

Fact is, a good sub is a good sub no matter the alignment. This sub is just crap.
It may be a bit of a simplification, but I still think that it's a good general rule. Look at ML's Summit/Vantage/Vista, AV123's Strata Mini's, etc. and you'll see that a sealed subwoofer is pretty common among these options.

Sealed subwoofers generally do give the tight and clean response that some audiophiles look for in their music. Personally, I'll find a middle ground, a sealed 10" subwoofer isn't going to fulfill my needs.

No it isn't a good general rule.

I don't look at any commercial products in order to justify my point of view, because that would not be wise. There are various reasons that commercial entities go with sealed subs, none of which include total performance. Also, your examples are nothing more than bass bins for main loudspeakers. We're talking about true sub woofers here.

The real reason so many have this 'boomy' opinion of ported subs is A) The quality of ported sub they heard B) The affect of the room on the sub causing a specific frequency range to be overly accentuated (i.e. one note bass)

Not just because the sub was ported.

Again, a good design is a good design. A sealed sub can sound like crap, and a ported sub can sound extremely clean and tight. You just have to look at the facts and open up your eyes....
Makes sense, the last part is what made it make sense to me. I guess you can make either good or bad depending on design and construction. I think I was thinking simply about choices at the higher end and not worried about getting any "bad" designs.
 

Excelsior

Lifer
May 30, 2002
19,047
18
81
Makes sense, the last part is what made it make sense to me. I guess you can make either good or bad depending on design and construction. I think I was thinking simply about choices at the higher end and not worried about getting any "bad" designs.

But this is where misinformation still lives. And I still don't like discussing this topic with reference to commercial products, as they are so severely limited. They are not a good representation.

Most commercial subs have so many limitations. With ported subs, it is generally size that limits them. Shipping a bunch of massive ported enclosures is not exactly viable (don't bring up SVS, those are not what I call massive). Sealed subs are obviously generally smaller, and pleasing to the masses because they usually don't mate with the room to create a single range of the FR that is over accentuated because room gain works with the roll-off.

So many ported subs though, are designed to be flat in an anechoic chamber. Put these in a room, and the gain throws that pretty FR out the window. But, if you design the ported sub to have a rolloff above the tuning frequency, it has a much better chance to have a flatter FR in-room. That, combined with a low-tuning, will make a good ported sub sound very nice.
 

Howard

Lifer
Oct 14, 1999
47,982
11
81
Excelsior knows what's up. A well-designed ported sub can be extremely pleasing to the experienced ear.
 

AgaBoogaBoo

Lifer
Feb 16, 2003
26,108
5
81
Damn, I stand corrected entirely, don't say this often, but thank you for posting that.

Edit: I avoided bringing up SVS because I've been realizing this limitation of size myself, Howard's been guiding me on some DIY options I have and I sincerely appreciate his help.
 

Gamingphreek

Lifer
Mar 31, 2003
11,679
0
81
Thanks so much for all the help guys. I MAY look for a new speaker system. I'll check the Audigy's control panel for an equalizer.

I do have 2 of those very very nice Isignia Bookshelf speakers from Best Buy (The ones that are Audiophile speakers if you do some sort of a mod on them) as well as some Pioneer Bookshelf Speakers. Here at College I am using them for the TV (Hooked up to an external receiver) but when I get back home they will be free. Is there any chance I can just buy a somewhat nice sub for ~$100? Is there then a way for me to hook those 4 speakers and a Center channel (Which I would buy) and a sub up to my computer- or would I need an External Receiver (Thereby requiring Dolby Live!)?

-Kevin
 

YOyoYOhowsDAjello

Moderator<br>A/V & Home Theater<br>Elite member
Aug 6, 2001
31,205
45
91
Originally posted by: Gamingphreek
Thanks so much for all the help guys. I MAY look for a new speaker system. I'll check the Audigy's control panel for an equalizer.

I do have 2 of those very very nice Isignia Bookshelf speakers from Best Buy (The ones that are Audiophile speakers if you do some sort of a mod on them) as well as some Pioneer Bookshelf Speakers. Here at College I am using them for the TV (Hooked up to an external receiver) but when I get back home they will be free. Is there any chance I can just buy a somewhat nice sub for ~$100? Is there then a way for me to hook those 4 speakers and a Center channel (Which I would buy) and a sub up to my computer- or would I need an External Receiver (Thereby requiring Dolby Live!)?

-Kevin

I don't know about "audiophile", but you can mod them to be as good as $200-$250 speakers

Do you have a receiver already then? Does it have a multichannel analog input?

Yeah, you could get another speakers and a sub and complete your 5.1 system. You might want to just get another pair of the insignias and make a 6.1 system so the front three speakers match.

If you have a receiver that does not have a multichannel analog input and need to do games, then yeah... you could get a card that encodes DD/DTS or you could get a new receiver.
 

grrl

Diamond Member
Jun 21, 2001
6,204
1
0
Originally posted by: davestar
Originally posted by: Gamingphreek
Originally posted by: davestar
a sealed sub enclosure typically produces the tightest bass of any enclosure configuration. definitely DO NOT drill a hole.

Then why in the world do Klipsch and Mackie and high end models have ventilated subs. It was my impression, that a closed unit with no exhaust produces deep boomy overwhelming bass, not a sharp clear bass like it is supposed to.

-Kevin

Some research material

from the above link: "[Sealed enclosures] are usually the subwoofer system of choice for audiophiles because of their excellent transient response (i.e. no boomy sound) characteristics when designed and built properly."


ported enclosures are designed in such a way that the port is tuned to a certain frequency. you get a response bump at that frequency and steep rolloff and distortion below that frequency.

decent sub manufacturers are careful to mate their driver (the speaker itself) with the proper enclosure. altering the enclosure is a definite no-no

FTW!
 

Excelsior

Lifer
May 30, 2002
19,047
18
81
Originally posted by: AgaBoogaBoo
Damn, I stand corrected entirely, don't say this often, but thank you for posting that.

Edit: I avoided bringing up SVS because I've been realizing this limitation of size myself, Howard's been guiding me on some DIY options I have and I sincerely appreciate his help.

No problem.

And although I was quoting you, I wasn't necessarily speaking to you directly about not bringing up SVS. Its just that so many folks thing 'omg, SVS subs are gigantic!". They really aren't, but I suppose it is all relative. If the new SVS owner previously had some cheapo HTIB sub, he'd obviously think the SVS sub is large.

Whereas my sub is ~2.5x the size of a 16-46. Then there are subs ~4.5x the size of a 16-46. It simply isn't viable shipping subs that large all over the country to ID customers, even if they offer substantially better performance. This is just one reason why I think most ID (even B&M) companies stick with the smaller drivers and enclosures. They can use less materials, charge the same price, and transport many more for the same price.

Howard definitely knows what he is talking about. I am sure he'll guide you well. ;)
 

Excelsior

Lifer
May 30, 2002
19,047
18
81
Originally posted by: grrl
Originally posted by: davestar
Originally posted by: Gamingphreek
Originally posted by: davestar
a sealed sub enclosure typically produces the tightest bass of any enclosure configuration. definitely DO NOT drill a hole.

Then why in the world do Klipsch and Mackie and high end models have ventilated subs. It was my impression, that a closed unit with no exhaust produces deep boomy overwhelming bass, not a sharp clear bass like it is supposed to.

-Kevin

Some research material

from the above link: "[Sealed enclosures] are usually the subwoofer system of choice for audiophiles because of their excellent transient response (i.e. no boomy sound) characteristics when designed and built properly."


ported enclosures are designed in such a way that the port is tuned to a certain frequency. you get a response bump at that frequency and steep rolloff and distortion below that frequency.

decent sub manufacturers are careful to mate their driver (the speaker itself) with the proper enclosure. altering the enclosure is a definite no-no

FTW!

Calling it a bump is so naughty (and wrong). It just augments the FR like outboard EQ does, but a 'bump' is never the intention.

Still, even though a ported sub has higher distortion, steeper rolloff, and begins unloading below Fb...it has significantly lower distortion and output capability at and above Fb (to a certain point). All the while the sealed sub has rapidly rising distortion from the start...

I'll let you two digest a couple of interesting tests. In one corner, we have well respected very expensive sealed servo unit, the Velo DD15. I am sure many of you are familiar with it.

http://www.avtalk.co.uk/forum/index.php?t=msg&th=14733&start=0&rid=0&SQ=0

And a relatively inexpensive SVS 20-39 PC Plus tuned to 12Hz.

Check out the distortion measurements, the group delay, the energy time frequency spectrum.

You might find the results somewhat surprising. Now imagine how the results would look if you took a custom ported design that was intended from the start for a low tune, with a much more capable driver.

http://www.avtalk.co.uk/forum/index.php?t=msg&th=13935&start=0&rid=0&SQ=0
 

Rubycon

Madame President
Aug 10, 2005
17,768
485
126
Originally posted by: Howard
Excelsior knows what's up. A well-designed ported sub can be extremely pleasing to the experienced ear.

The problem with reflex systems is their drivers (and output) will get out of control quickly when the inexperienced user/listener tries to make the speaker do something it isn't supposed to do. A good driver can compensate for this but many will slap which must be avoided always. :Q

SVS has taken an old idea that a lot of curious users would do - change the port tuning with a plug. Of course the DIY can go much further with differing sizes of tubing, length, etc. Passive radiators can have weight added or removed (VMPS cabs touted this feature). A sealed enclosure can have its response extended with a hefty EQ - providing amp power, thermal, and mechanical limits of the driver are carefully considered.

I just wish they would stop calling those little boxies on computer speaker systems subwoofers. :|

The velo and SVS systems have impressive responses but would be considered rather quiet systems. They seem to have fairly high outputs in the very audible ranges above 20 Hz, but touting "12Hz" extension is a gimmick because the human ear needs lots of SPL to realistically hear these frequencies and you're on the onset of driver mechanical limitations (as well as amp limitations) and into the onset of the dreaded C word (compression) so they really lose punch quickly.

The Eminence TRW17 just scrapes on the tip of the iceberg of what can be realized in the infrasonic region and other designs are on the horizon (one a totally solid state one!) that will follow that's been tested in an airlock - DC capable! :Q but these avant-garde solutions are hardly mainstream and will only be realized by the hardcore bassophile that has to get every possible frequency in the air and out of the playback medium. The laws of diminishing returns quickly follow here but a system that can sustain 120dB SPL at 20Hz minimum continuous output (at the listening position) with low distortion is usually considered "decent" by the majority. ;)

You will NEVER realize that with ANY PC speaker "subwoofer" module on the market. Perhaps if the voice coil was wired to a little Jack Russell puppy that humped your leg at 20 cps you would FEEL that but we'll leave the kinky stuff out of the audio scene. (even though some may feel audio reproduction is somehow related to other fetishes. ;) )

 

Howard

Lifer
Oct 14, 1999
47,982
11
81
Originally posted by: Rubycon
Originally posted by: Howard
Excelsior knows what's up. A well-designed ported sub can be extremely pleasing to the experienced ear.
I just wish they would stop calling those little boxies on computer speaker systems subwoofers. :|
Bass modules :D
 

Gamingphreek

Lifer
Mar 31, 2003
11,679
0
81
Originally posted by: YOyoYOhowsDAjello
Originally posted by: Gamingphreek
Thanks so much for all the help guys. I MAY look for a new speaker system. I'll check the Audigy's control panel for an equalizer.

I do have 2 of those very very nice Isignia Bookshelf speakers from Best Buy (The ones that are Audiophile speakers if you do some sort of a mod on them) as well as some Pioneer Bookshelf Speakers. Here at College I am using them for the TV (Hooked up to an external receiver) but when I get back home they will be free. Is there any chance I can just buy a somewhat nice sub for ~$100? Is there then a way for me to hook those 4 speakers and a Center channel (Which I would buy) and a sub up to my computer- or would I need an External Receiver (Thereby requiring Dolby Live!)?

-Kevin

I don't know about "audiophile", but you can mod them to be as good as $200-$250 speakers

Do you have a receiver already then? Does it have a multichannel analog input?

Yeah, you could get another speakers and a sub and complete your 5.1 system. You might want to just get another pair of the insignias and make a 6.1 system so the front three speakers match.

If you have a receiver that does not have a multichannel analog input and need to do games, then yeah... you could get a card that encodes DD/DTS or you could get a new receiver.

They sounds great to me, but just out of curiosity, how good are they after the mod?

Well I have an old Sony receiver. Does not have DD/DTS support, has rudimentary surround support- but the surround channels I believe are partially screwed up. The Pioneer speakers aren't bad, but I doubt they would be on the same level as the Insignias after the mod.

How much would it be for me to get a good sub and receiver? Perhaps I can convince my Dad to give me his entry level Sony 5.1 system and I can get him set up with a proper system.

-Kevin
 

sdifox

No Lifer
Sep 30, 2005
100,237
17,895
126
Originally posted by: Gamingphreek
Originally posted by: davestar
a sealed sub enclosure typically produces the tightest bass of any enclosure configuration. definitely DO NOT drill a hole.

Then why in the world do Klipsch and Mackie and high end models have ventilated subs. It was my impression, that a closed unit with no exhaust produces deep boomy overwhelming bass, not a sharp clear bass like it is supposed to.

-Kevin

They are designed differently. Different pros and cons of course. DO NOT DRILL HOLES!
 

YOyoYOhowsDAjello

Moderator<br>A/V & Home Theater<br>Elite member
Aug 6, 2001
31,205
45
91
Originally posted by: Gamingphreek
Originally posted by: YOyoYOhowsDAjello
Originally posted by: Gamingphreek
Thanks so much for all the help guys. I MAY look for a new speaker system. I'll check the Audigy's control panel for an equalizer.

I do have 2 of those very very nice Isignia Bookshelf speakers from Best Buy (The ones that are Audiophile speakers if you do some sort of a mod on them) as well as some Pioneer Bookshelf Speakers. Here at College I am using them for the TV (Hooked up to an external receiver) but when I get back home they will be free. Is there any chance I can just buy a somewhat nice sub for ~$100? Is there then a way for me to hook those 4 speakers and a Center channel (Which I would buy) and a sub up to my computer- or would I need an External Receiver (Thereby requiring Dolby Live!)?

-Kevin

I don't know about "audiophile", but you can mod them to be as good as $200-$250 speakers

Do you have a receiver already then? Does it have a multichannel analog input?

Yeah, you could get another speakers and a sub and complete your 5.1 system. You might want to just get another pair of the insignias and make a 6.1 system so the front three speakers match.

If you have a receiver that does not have a multichannel analog input and need to do games, then yeah... you could get a card that encodes DD/DTS or you could get a new receiver.

They sounds great to me, but just out of curiosity, how good are they after the mod?

Well I have an old Sony receiver. Does not have DD/DTS support, has rudimentary surround support- but the surround channels I believe are partially screwed up. The Pioneer speakers aren't bad, but I doubt they would be on the same level as the Insignias after the mod.

How much would it be for me to get a good sub and receiver? Perhaps I can convince my Dad to give me his entry level Sony 5.1 system and I can get him set up with a proper system.

-Kevin

I have not heard the insignias before or after the mod.
http://www.gr-research.com/insignia.htm

Not sure what you mean about he surround being messed up. So it's a Dolby Prologic receiver?

A new receiver should be on your list of things to get then if you're hoping for a decent 5.1 system. The Onkyo 504 was on sale for $170 earlier this week which was a good deal on a budget receiver.

A very basic sub would run about $125 or so
Example http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=300-633

You asked about a "good" receiver and sub. Well, depends on what you mean by "good" ;)
 

Excelsior

Lifer
May 30, 2002
19,047
18
81
I've heard those Insignias in my room, and they are not bad at all for $40 on sale (or however much they are).