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Mark_IDT
05-06-2005, 10:07 AM
I've been doing some reading trying to figure out what type of sub I should get. I'm trying to narrow down search to what types would suite my needs best. I'm pretty sure I would like a sealed sub best but would a servo have it's place with the music I listen to? I listen to NIN, Tool, Crystal Medhod, some rap but mostly rock. NIN and Crystal Method use alot of synthesized bass they are the most demanding bass cds in my collection. I know the basics of how a servo works and how they are very accurate but for the music I listen to would a servo have it's place? If I don't go servo I have my eye on Adire's tumult in a sealed box.

kexodusc
05-06-2005, 10:28 AM
Can we first ask a few questions of you to get a better idea of your needs?
How large is the room? How loud do you typically listen (in dB's if possible)? What is your budget?

Mark_IDT
05-06-2005, 10:43 AM
Room size I can't specify I'm 22 and in the last 4 years I've lived 3 different places so I just want to go big and I can always turn it down. I listen to music very loud and it would most likely end up powering some fraternity parties. I want to get a subwoofer to end all desire for a bigger subwoofer so I'm willing to pay $2000 - $3000. I'm not looking for suggestions on subwoofer brands or models at the moment I just want to know what type would suite me best first then I'll go searching for brands.

kexodusc
05-06-2005, 11:08 AM
You can always have more bass.
If you were in a permanent location, or have some savy buddies at college who are handy around a house, I would suggest abandonning servo designs in favor of infinite baffle designs.

Basically you use a big woofer (or multiple woofers) in an adjacent room and turn the room you're in into a giant subwoofer cabinet.

I think servo subs are still generally too expensive for the relative performance, just my opinion, but they do offer high output and low distortion all in a convenient package, maybe if they ever produced in larger quantities we'd see them become a bit more affordable.

That being said, I'd expect two 15" Tumults with two 500 watt plate amps to lay a serious thumping to any $2000-$3000 servo sub. Perhaps not always in terms of max SPL, but in overall sound quality and performance.
The Tumults would put you at about $1900 plus shipping. Throw in an extra $150 for MDF, polyfill, and a nice vinyl, paint, or even veneer for finishing and you're set for under $2200. I see no reason to go bigger. If you can't build your own cabinets, you can buy decent black ones for $150 to $200 each from a few places.


Lots of big, loud, good sounding woofer options out there, many of them less money than the Tumults...some might not have the same sound quality, but they might be better values...I don't know I just threw this at you to get you started.

Two Tumults would have no problem getting you arrested for disturbing the peace. Want to spend the rest of your money? Upgrade to two 1000 watt plate amps and two 18" Tumults for $300 more and you're into thunderclap/sonic boom levels of output.

#@*% YEAH!!!

Mark_IDT
05-06-2005, 11:25 AM
I am that savvy buddy who's handy around the house :-) I'm a student of industrial design so building stuff is basically my degree were taught to be able to basically build anything out of anything. Tell me more about this infinite baffle design.



That being said, I'd expect two 15" Tumults with two 500 watt plate amps to lay a serious thumping to any $2000-$3000 servo sub. Perhaps not always in terms of max SPL, but in overall sound quality and performance.



I thought servos traded SPL for sound quality?

Geoffcin
05-06-2005, 02:56 PM
I am that savvy buddy who's handy around the house :-) I'm a student of industrial design so building stuff is basically my degree were taught to be able to basically build anything out of anything. Tell me more about this infinite baffle design.




I thought servos traded SPL for sound quality?

A 15" Servo sub will play just as loud as a non servo sub. The difference will only be in the distortion levels. If your planning on blasting to deafining levels then the extra money spent for a servo sub might be better spent on larger subs that have a higher absolute SPL. Of courese you could also try the used market too. A Forum member just posted that he found an 18" servo sub for $750.

kexodusc
05-06-2005, 05:15 PM
Geoffcin brings up a good point - used servo's are cheap.

Yeah, as far as I know (which admittedly isn't a whole lot when it comes to servo motors), they just cut down on the distortion during high output. The jury is out whether it's a real-world benefit, since our ears are not terribly good at reading distortion.
I dunno, but less distortion can never be a bad thing, so why not? I've never seen any low power, low output servo subs...they're all pretty beefy as far as I know.
Doesn't mean they're better, but they certainly aren't compromised in any way.

Geoffcin
05-06-2005, 05:26 PM
Geoffcin brings up a good point - used servo's are cheap.

Yeah, as far as I know (which admittedly isn't a whole lot when it comes to servo motors), they just cut down on the distortion during high output. The jury is out whether it's a real-world benefit, since our ears are not terribly good at reading distortion.
I dunno, but less distortion can never be a bad thing, so why not? I've never seen any low power, low output servo subs...they're all pretty beefy as far as I know.
Doesn't mean they're better, but they certainly aren't compromised in any way.

Although non-servo subs have come a long way in the last few years. IT used to be that it was easy to get a sub to distort past 10%, some even to 30%. Now I see subs that claim much lower levels. Servo subs have been getting better too, although I don't see the point of having to sample a 20hz tone 8000 times a second.

Mark_IDT
05-06-2005, 06:01 PM
I didn't mean to say servo subs aren't loud but rather that there are non servo subs that have higher spl's from the same sized speaker. Is this true? Also anyone know how much distortion the tumult would have in a sealed enclosure? I'm not afraid of used equipment but it can be a hassle to find what your looking for sometimes.

Woochifer
05-06-2005, 06:18 PM
Might want to contact Acoustic Visions and see what they can build for you. Their Everest sub uses two 15" Adire Tumult drivers plus four 15" passive radiators. The thing weighs 400 lbs. without the amplifier. But, they also sell scaled down subs built around the Tumult driver, either as kits or as prefinished subs.

I'm not as well versed on the principles of a servo-based sub as the others, but I believe that Adire's drivers are dual coil designs, so they can be used with one of the coils serving as an electromagnetic brake of sorts. Not sure if this function is similar to what a servo does, but it's another option to look into when configuring the sub.

http://www.acoustic-visions.com

kexodusc
05-07-2005, 03:32 AM
Although non-servo subs have come a long way in the last few years. IT used to be that it was easy to get a sub to distort past 10%, some even to 30%. Now I see subs that claim much lower levels. Servo subs have been getting better too, although I don't see the point of having to sample a 20hz tone 8000 times a second.

This is true, though 10% distortion below 80Hz is pretty much impossible for the human ear to read. I remember 5 years ago even it was common to see 10% as a standard distortion figure, now it's below 1% often...remarkable how far we've come.

Hard to say, but I think the breakthroughs in motor/cone control and improved efficiency in drivers might have made servo tech obsolete. I don't doubt it's potential to sound better, but there isn't enough production probably due to the much higher costs. Safe to say servo tech hasn't had as much attention paid to it yet.

I've only heard a few servo models because they're hard to find in smaller towns, most of those I heard when I lived in Atlanta a few years back, so maybe they've improved drastically. I've heard non-servo subs that sounded better.

I've read more than a few DIYers out there who've gone that route and never looked back. These guys are 15 years ahead of my abilities and most I've read about claim it was their most difficult project, but well worth it. Maybe someday...

I wonder if it's a planar/stat thing were they become loyal to the point of cult-like worship?

kexodusc
05-07-2005, 04:11 AM
I didn't mean to say servo subs aren't loud but rather that there are non servo subs that have higher spl's from the same sized speaker. Is this true? Also anyone know how much distortion the tumult would have in a sealed enclosure? I'm not afraid of used equipment but it can be a hassle to find what your looking for sometimes.
Distortion in most subs today isn't going to be a problem provided you match the power input to the woofers specs and don't feed signals to the woofer to far below it's frequency of resonance.
Soft clipping circuitry in a plate amp is a godsend and pretty much elimanates this, but hard to find on bigger amps.
If you want to learn more about Infinite Baffle setups, a great page to start can be found here:
http://home.comcast.net/~infinitelybaffled/
I've only ever heard two setups...it takes spousal approval that I doubt I'll be getting anytime soon, but the results are so worth it....the woofers in these weren't overly spectacular either, 2 under $200 each, the others I don't know for sure, but they probably weren't $200 each either.. In my opinion all subs should be built this way.
Part of the theory is to separate the front bass wave from the rear bass waves (not to be confused with transmission line speakers) so that there is no cancellation going on, but it's much more complicated than that.
Not difficult to do though. The guys at this site are great and would love to convert anyone.
Someday I hope to re-do my room with this in mind, but that's years away.

This Guy
05-07-2005, 09:35 AM
If he wants loud music why not go with a horn sub (s) like the Lab 12? Since hes good at making stuff, i think these would be perfect. Make a couple of them and stack them in a corner. The total would be about $1000 i think.

Mark_IDT
05-09-2005, 05:50 PM
Sounds like I'll be making one of the first newly updated Tumult subs this summer. I'll probably get one first and a second when I have more money. Thanks for the help guys.