Big Velodyne subs. Thinking of going with another line cause I'm not happy

[DrWho]

an SPL meter is very inaccurate at the lower frequencies (+-10dB) but

with pink noise gives a good relative volume to the mains (for when

setting levels).

An RTA is the next best thing and requires a calibrated microphone (the

behringer ECM 8000 i believe is the model costs $50). Keep in mind that

a condensor mic needs a phantom power source (so you need to connect it

up through a mixer of some sort....behringer has one of those for $50

too). And then you will need the RTA unit itself....stand alone ones

cost a lot - like in the hundreds to thousands. However you can get PC

based ones for free - or you can spend a bit of money ($100-$300) to

get some really cool software.

Which bleeds over into the second category...TEF and all that shnazz

that takes into account the time domain (takes a bunch of measurements

over time). These are nice for determining specific annoying room

issues and going from there. This software however is still in its baby

stages (rather new) and costs a lot of money.

Btw, I still think an infinite baffle subwoofer system is the way to go

for you...perhaps you should build a new house just to support this

[] (I know my future home is going to be built around it)

[dragonfyr]

After a quick perusal I still have no idea amidst all the '(ir)rationale' of exactly what is being done, but suffice it to say - if you haven't done it already, set the speakers to "small"!

And regarding the inordinate desire to get another 18" sub to reproduce the lowest octave, please pray tell, tell us what you are listening too that actually has consistent meaningful content between 15-30Hz requiring a dedicated sub in addition to the Velodyne!?!?!?!?!? Explosions!?!?!?[]

Yep you definitely need at least one more! Maybe two, as then you can make sure that both the 15-20Hz and the 20-30Hz bandpass are adequately and individually represented![]

And as far as software goes - wow, this is definitely a case where more analysis would have benefited us (Warning!! Danger Will Robinson!!) - as if any more illogic might have indeed resulted in some type of explosion and personal injury!! (was that put sarcastically enough???), After all, it doesn't matter WHAT tools you have if the initial questions are not framed correctly!

But hey, trust me, you haven't encountered sarcasm yet!

But who in the heck needs an expensive RTA????????????

And who in the right mind, or wrong mind for that matter!, needs to buy a TEF for casual measurements!? The TEF software is VERY mature. And Far more advanced then most thinking!!!![]

For less then what many are paying for interconnects, you can get ETF software and a mic that provide time based MLS measurements, complete with 3D waterfalls, and more measurements then a wimpy RTA could ever provide! And for less money then an RTA!

Of course then some might feel compelled to discover just what measurements can be obtained, and then of course what all the measurements mean (did those words just come from ME!?), which might then lead to some asking what or why would someone find such measurements valuable and what does that say about the nature of sound. Now I realize that this is a completely @ss-backwards way of inadvertently backing into an increased understanding of some of the 'acoustics' that seem to be happening...and we should all be very afraid of that!...

But isn't it about time that we get past the 'let's spend the big bucks on a fancier SPL meter' phase and at least pretend that we have a greater understanding of acoustics then what was state of the art in 1940 when the 'science' (now there is a misused word!) was all of almost 70 years old!

http://www.etfacoustic.com/

So check it out! For just $150 plus a cheap mic (you don't need the B&K or an Earthworks M30!!! NOR even the IMP mic they sell!), and for less then a mediocre RTA, you can confuse yourself royally with time based measurements! And think of the fun and confusion that can result from the misapplication of THESE measurements! Just that possibility alone should have folks running to order this stuff as the contributions on this site will assume an even more festive flavor of insanity!

Thanks Doc for taking the time to try to wade though this grand example of why a license should perhaps be required for the purchase of a subwoofer!

[][][6] LMAO!

[Fast1]

Actually DrWho, my plan is to build a home around my system. My plan is top secret as to the design because of friends that like to duplicate my work. I am just stockpiling my components and once I find the combo I like, I will not change for many years, maybe! I may sacrifice some acoustics to get what I want so I am real sure I won't have a bunch of these acoustic cylinders sitting around everywhere or something like that. Who knows where I will go from here with the design but plan for now will include all walls and ceiling to be concrete except the entrance wall. This is purely for sound insulation for the rest of the house and wil double as a saferoom for bad weather. This way my system and family will be safe!!

[dragonfyr]

Now that IS a disaster plan![][6]

[TheEAR]

Velodyne HGS and SPL subwoofers cannot bottom out,the limiters will kick in before any bottoming out or amp clipping gets the better of it.In fact most known well designed powered subwoofers have limiters and will not bottom outsave for some extreme tests and extreme rare cases.

Like was said set your mains to small and let the subwoofer do the work down low.You speakers may be fighting a never ending battle with your sub even when phas and crossover appear ok.Set mains,center and sourrounds to small.

There is no way you should be bass deprived after the corrections are done.

[boomer9911]

I own a Velodyne FSR-18 to go with my Heritage HT(Khorns, Hersy II's, LaScala's, KLFC7) with main components being Marantz Reference for the last couple of years.....can't say I have much to complain about that brute...except..."down boy"....[mo]

[Fast1]

Ok my next question is if anyone can give an opinion of quality bass from the Velodyne vs other comp lines? I hear about the svs and sunfire. I guess my thing with Velodyne has been that servo to control distortion and I know they sound pretty clean on the bottom. My room is I think 14x35 or so. I am already sure that I will need another 18" or so for the type of output I want. I hear about the infinite baffle units, who has them? Are they for me? Size is no biggy for me. Thanks.

[DrWho]

IB is completely DIY, but is really easy to build (so you're not going

to find an "IB Subwoofer", but you will find drivers with the right T/S

parameters). All you need is an adjoining room (attic, basement,

garage, etc...) that houses the rear end of your subwoofers. Basically

all you need to do is keep the sound from the back of the driver away

from the sound in front of it, thus the term "infinite baffle" (which

is the entire concept behind a subwoofer cabinet actually). if you do a

search online you will find all sorts of pictures and measurements. I

know there's a few good main sites, but I don't have any of them in my

favorites list. When I find a few I will post them, but I'm sure the

others will beat me to it.

[travisc]

http://forums.klipsch.com/forums/573183/ShowPost.aspx

great stuff dr who I am loving your advice in this thread thanks

[DrWho]

lol, you just had to post that thread []

[dragonfyr]

Ok my next question is if anyone can give an opinion of quality bass from the Velodyne vs other comp lines? I hear about the svs and sunfire. I guess my thing with Velodyne has been that servo to control distortion and I know they sound pretty clean on the bottom. My room is I think 14x35 or so. I am already sure that I will need another 18" or so for the type of output I want. I hear about the infinite baffle units, who has them? Are they for me? Size is no biggy for me. Thanks.

Brandon, only because you have the audacity to ask such a pointed question...

Are they for YOU!?

You, my friend, just may be the cause of the government requiring warning labels on subs!

Or, perhaps having them taken away from you (or us!) entirely!

But since I believe that its each individual's responsibility to make informed decisions, I am only too glad to provide you with a source for the scissors! Run with them!

http://home.comcast.net/~infinitelybaffled/

http://home.comcast.net/~infinitelybaffled/page2IB-IBmanifold.html

Everyone else...Stand back! You've been warned![]

[travisc]

thats what came to mind reading this thread. Overkill think overkill

[Olorin]

Overkill? You mean "headroom," right? []

[Fast1]

Well in my area of expertise, there is no replacement for displacement. I guess since the human ear (and other senses) are not as sensitive to very low frequencies, I want to add more in the 15-25hz area. As I educate others with my high output motors, some times we must use throttle restraint or in this case volume restraint. I want the extra headroom and will more than likely enjoy just trying to rattle my roof trusses for fun from time to time. Never the less I think everyone is so concerned about why. One must realize that if I obtain an overwhelming amount of sub bass, I can just --turn it down--

[dragonfyr]

Well in my area of expertise, there is no replacement for displacement. I guess since the human ear (and other senses) are not as sensitive to very low frequencies, I want to add more in the 15-25hz area. As I educate others with my high output motors, some times we must use throttle restraint or in this case volume restraint. I want the extra headroom and will more than likely enjoy just trying to rattle my roof trusses for fun from time to time. Never the less I think everyone is so concerned about why. One must realize that if I obtain an overwhelming amount of sub bass, I can just --turn it down--

ROFLMAO

I am sure you will educate many with the abundance of information available in the 15-25Hz range! By the way, just how DO you determine if the sound of a planet exploding is accurate. Should we be expecting a new episode of NOVA to result from this project?

And yes, I would agree that the sense of smell is slightly less sensitive to LF then is, say, the sense of sight. Heaven forbid you should discover that most low frequency information is transmitted by conduction, and not via the outer ear. Perhaps you should discover LF shakers.

Actually, I must admit that I have been wondering a few other things...[]

[TheEAR]

Well in my area of expertise, there is no replacement for displacement. I guess since the human ear (and other senses) are not as sensitive to very low frequencies, I want to add more in the 15-25hz area. As I educate others with my high output motors, some times we must use throttle restraint or in this case volume restraint. I want the extra headroom and will more than likely enjoy just trying to rattle my roof trusses for fun from time to time. Never the less I think everyone is so concerned about why. One must realize that if I obtain an overwhelming amount of sub bass, I can just --turn it down--

ROFLMAO

I am sure you will educate many with the abundance of information available in the 15-25Hz range! By the way, just how DO you determine if the sound of a planet exploding is accurate. Should we be expecting a new episode of NOVA to result from this project?

And yes, I would agree that the sense of smell is slightly less sensitive to LF then is, say, the sense of sight. Heaven forbid you should discover that most low frequency information is transmitted by conduction, and not via the outer ear. Perhaps you should discover LF shakers.

Actually, I must admit that I have been wondering a few other things...[]

What is wrong mushroom with legs? Are you not taking your prsescription medication!

If someone here wants a 80" subwoofa mounted on a mini cooper let him have his woofa and go deaf.Do not ask WHY.

I for one have many many ...many subs.WHY? BECAUSE it aint of your damn business buddy.I like overkill and that is that.

How does a planet exploding sound,nobody knows exactly.And no miserable subwoofers made by little humans can even begin to replicate the scale.You want to have a good idea,go to a nuke test site and place your ear on the device and listen for the boom.Then you will be able to tell us all. []

[dragonfyr]

As I said in the post, I don't give a damn why!

Go hump someone else's leg!

Don't you and the language police ('Office of French Language' huu huuaa!) have enough issues dealing with those miscreant McDonald's folks for not having a French name?

[Fast1]

Well I guess you know that you don't actually hear 15hz anyway. The human body responds to this frequency as pressure pulses which also means the simplest things like air movement over the hair on your arms and yes the nose and sinus cavities helps the body to decided whether there is really any frequency or compression wave at all. This is also the reason some people get sick when introduced to LF waves. An upset of in and outer ear equalibrium.

[TheEAR]

What are you blabling about ? What humping has to do with subwoofers? What is wrong little one? Dr THXberg did not give you a stong enough dose! []

And what has McDonald's have to do with subs,and where did you dig up the police? Go see a doctor

your paranoia is out of control [:|]

[formica]

Basically an Infinite Baffle [iB] sub (web site has move BTW to

http://ibsubwoofers.proboards51.com/index.cgi) is a sealed subwoofer

with a very large enclosure. The key here is we aren't talking

about 2ft3 or 8ft3... but more in the 800ft3 range. Obviously no

one can let that much interior volume go to waste... so many builders

use one room as an enclosure and the other as their listening room.

The link http://home.comcast.net/~infinitelybaffled/ Dragonfry posted

contains the FAQ behind the design... which applies Hoffman's law to a

tee. Then the article travisc posted is an infamous IB installed

by Tom Nousaine which spawned ThomasW 's own designs and internet

community.

IB is the design to use if you are looking for a no compromise

subwoofer. I've decided to go this route myself... and will have

16L

of displacement using 6 Acoustic Elegance IB15 and a EP2500 amp.

I still have to complete my basement modifications to house the

backwave...

Rob