Calibrating subwoofer in a 2.1 studio nearfiled environment

[Drumsix]

Hi guys,

is there any rule or lecture how to calibrate a subwoofer in a 2.1 studio
nearfield environment.
How do you setup up the fase switch (0, 180), crossover frequency and volume
of the subwoofer?
Is the only good way with a spectrum analyzer or can it be done by ears?

TIA.

Drumsix

[Mike Rivers]

Drumsix wrote:

> is there any rule or lecture how to calibrate a subwoofer in a 2.1 studio
> nearfield environment.

About the only "trick" I've run across is to put the subwoofer
temporarily in the position where you normally listen, play some music
through it, and walk around the room listening for where it's the
loudest. This isn't as simple as it sounds because it may be difficult
to get the subwoofer up at head height (most say just put it on a chair
- assuming you hear bass with your butt) and there may be some places
where you can't get your head where you could put the speaker. But it's
a start.

> How do you setup up the fase switch (0, 180), crossover frequency and volume
> of the subwoofer?

So that it sounds best.

> Is the only good way with a spectrum analyzer or can it be done by ears?

Most spectrum analyzers aren't very accurate at low frequencies, so
it's best to do it by listening. A spectrum analyzer might help you to
tell if you've created a "hole" in the frequency response by having the
crossover frequency set incorrectly, but generally the manufacturer of
the speaker will recommend a crossover frequency. Start with that and
listen for anything missing.

Bear in mind that a truly accurate subwoofer is quite expensive and is
worth getting some professional help in setting it up. If you have a
department store subwoofer, chances are it's only going to reproduce a
narrow range of frequencies, mostly giving more thump to your bass drum
sounds. They're placement is less critical because they do less for the
total sound, and pretty much just require your judgment in how much
thump you like.

[Drumsix]

Mike,

thanks for your advice. I'm from holland, and my english is not fluent so I
don't really know what you mean by "department store" subwoofer.

When I read your reply the only best thing for me to do is listen how the
sub sounds best, do a mix ( usualy 24 track) and listen out on it on
differnt audio systems (car, home set, etc) and see if the sound is what I
expected it to be. (talking about a long sentence).

I bought it because my nearfield monitors where a bit thin on the low end.
I only put a bit of sub volume know to my 2.1 system and the overall sound
on other systems is allready better.

Greetz,

Drumsix

"Mike Rivers" > schreef in bericht
oups.com...
>
> Drumsix wrote:
>
>> is there any rule or lecture how to calibrate a subwoofer in a 2.1 studio
>> nearfield environment.
>
> About the only "trick" I've run across is to put the subwoofer
> temporarily in the position where you normally listen, play some music
> through it, and walk around the room listening for where it's the
> loudest. This isn't as simple as it sounds because it may be difficult
> to get the subwoofer up at head height (most say just put it on a chair
> - assuming you hear bass with your butt) and there may be some places
> where you can't get your head where you could put the speaker. But it's
> a start.
>
>> How do you setup up the fase switch (0, 180), crossover frequency and
>> volume
>> of the subwoofer?
>
> So that it sounds best.
>
>> Is the only good way with a spectrum analyzer or can it be done by ears?
>
> Most spectrum analyzers aren't very accurate at low frequencies, so
> it's best to do it by listening. A spectrum analyzer might help you to
> tell if you've created a "hole" in the frequency response by having the
> crossover frequency set incorrectly, but generally the manufacturer of
> the speaker will recommend a crossover frequency. Start with that and
> listen for anything missing.
>
> Bear in mind that a truly accurate subwoofer is quite expensive and is
> worth getting some professional help in setting it up. If you have a
> department store subwoofer, chances are it's only going to reproduce a
> narrow range of frequencies, mostly giving more thump to your bass drum
> sounds. They're placement is less critical because they do less for the
> total sound, and pretty much just require your judgment in how much
> thump you like.
>

[Ethan Winer]

> is there any rule or lecture how to calibrate a subwoofer in a 2.1 studio
nearfield environment. <

The only way to know which sub location is best, and what sub volume level
and phase setting is best, is to measure as accurately as possible. You
cannot use a typical third octave analyzer for this because the peaks and
nulls in small rooms are very narrow at low frequencies. Look at this graph,
measured in a 16 by 10 room - note the peak/dip pair at 110 and 122 Hz where
the response varies a staggering 32 dB across a range smaller than one
musical whole step:

www.realtraps.com/art_response.gif

This is what you're up against, and the only way to set up a subwoofer to
make the most of this VERY TYPICAL situation is to measure at 1 Hz or
finer resolution. This graph was plotted using 1 Hz tones (which took a
while), but now I use the ETF and R+D software from these guys (which
takes only a few seconds):

www.acoustisoft.com

You'll never get the response even close to flat unless you also treat the
room (bass traps). But you can at least make it better with careful
positioning and setup, and that requires being able to measure accurately.

--Ethan

[Mike Rivers]

Drumsix wrote:

> thanks for your advice. I'm from holland, and my english is not fluent so I
> don't really know what you mean by "department store" subwoofer.

It's not a matter of English, it's a colloquialism. What I was
referring to was an inexpensive subwoofer designed to use with a cheap
home stereo system or computer speakers. Over here, those generally
sell for $50-100, then there's a pretty big price gap before you get to
speakers that have reasonably flat frequency response in the 20 to 80
Hz range.

> When I read your reply the only best thing for me to do is listen how the
> sub sounds best, do a mix ( usualy 24 track) and listen out on it on
> differnt audio systems (car, home set, etc) and see if the sound is what I
> expected it to be. (talking about a long sentence).

That's secondary. First, just listen to some CDs that you're familair
with, both with the subwoofer and with the subwoofer switched off. That
way you can tell what it's doing, and whether it's enhancing the sound
in a good way or a bad way.

> I bought it because my nearfield monitors where a bit thin on the low end.
> I only put a bit of sub volume know to my 2.1 system and the overall sound
> on other systems is allready better.

If it lets you hear a range that you can't hear without the subwoofer,
and that if, by making adjustments that affect that range (or the
balance with it) you can make better mixes, then it's doing its job.
With some subwoofers that have a large reonance peak, there isn't much
you can do in the mix to change what you hear coming out of it. No
matter what goes in on the low end, pretty much the same thing always
comes out. That's not accurate, but it annoys the neighbors and people
in adjacent cars. <g>

[Drumsix]

Mike,

With your sentence, "It's not a matter of English, it's a colloquialism", it
becomes a matter of English (haha). I haven't got a clue what the collo...
word means?

I use Alesis Monitor One nearfields an a Samson Sub88, attached to a tascam
Dm24 Digital mixer and a Nuendo recording setup with RME soundcards.
I'm well aware of the fact that I don't own a Preffesional Studio. I use it
for mixing my own bands and for mixing some other bands. Mostly live gigs.

The track that Ethan Winner suggest in an other reply on this subject is
obviously a good one, but is more for a proffesional studio (I think).
I'm mostly on the road an when I have the time for some mixing, I want it to
be as good as my equipment and time let it to.

As you suggested I played some tracks that in my opinion sounds great (from
classical and bigbands to rock (sacd)) and from there on I tweaked the sub
for what I thought is the best sound. But with all self adjustments you
never know if its the right way as a standard. That's why I posted this
question.

When I switch the sub on I hear and feel some more air to my mixes. It's
not that I use it for more bass, but the lower end doesn't sound as thin and
packed anymore. So in that opinion I think the sub is doing his work. (or
her work, bass for me is something as a gracious female, but let's stay on
topic).
The main thing (among others) for me is that my base drum and the bass
guitar sound more like a pair to me than two different instruments.

Greetz,

drumsix


"Mike Rivers" > schreef in bericht
oups.com...
>
> Drumsix wrote:
>
>> thanks for your advice. I'm from holland, and my english is not fluent so
>> I
>> don't really know what you mean by "department store" subwoofer.
>
> It's not a matter of English, it's a colloquialism. What I was
> referring to was an inexpensive subwoofer designed to use with a cheap
> home stereo system or computer speakers. Over here, those generally
> sell for $50-100, then there's a pretty big price gap before you get to
> speakers that have reasonably flat frequency response in the 20 to 80
> Hz range.
>
>> When I read your reply the only best thing for me to do is listen how the
>> sub sounds best, do a mix ( usualy 24 track) and listen out on it on
>> differnt audio systems (car, home set, etc) and see if the sound is what
>> I
>> expected it to be. (talking about a long sentence).
>
> That's secondary. First, just listen to some CDs that you're familair
> with, both with the subwoofer and with the subwoofer switched off. That
> way you can tell what it's doing, and whether it's enhancing the sound
> in a good way or a bad way.
>
>> I bought it because my nearfield monitors where a bit thin on the low
>> end.
>> I only put a bit of sub volume know to my 2.1 system and the overall
>> sound
>> on other systems is allready better.
>
> If it lets you hear a range that you can't hear without the subwoofer,
> and that if, by making adjustments that affect that range (or the
> balance with it) you can make better mixes, then it's doing its job.
> With some subwoofers that have a large reonance peak, there isn't much
> you can do in the mix to change what you hear coming out of it. No
> matter what goes in on the low end, pretty much the same thing always
> comes out. That's not accurate, but it annoys the neighbors and people
> in adjacent cars. <g>
>

[Mike Rivers]

Drumsix wrote:

> With your sentence, "It's not a matter of English, it's a colloquialism", it
> becomes a matter of English (haha). I haven't got a clue what the collo...
> word means?

>From some dictionary web site or other:

An informal words, or phrase of conversational language that brings
color to everyday speech and a friendly, conversational tone to
writing; many are figures of speech that are not meant to be taken
literally, such as fly off the handle, foot the bill

> As you suggested I played some tracks that in my opinion sounds great (from
> classical and bigbands to rock (sacd)) and from there on I tweaked the sub
> for what I thought is the best sound. But with all self adjustments you
> never know if its the right way as a standard. That's why I posted this
> question.

There are no standards, but there are some limits. You don't want to
drive the subwoofer with enough signal so that its amplifier clips. I
couldn't find a manual for your subwoofer on the Samson web site, but I
assume it works like most other subs in this class - you feed the left
and right signal into the subwoofer and that goes through the
crossover, feeding everything above the crossover out to a pair of
jacks that go to the main speakers. So you want to set the crossover
frequency somewhere above the lowest frequency that the main speakers
can handle, but not so high that the subwoofer can't reproduce
everything that's sent to it. Anywhere in that range, you'll get all
the lows, but the'll move from the main speakers to the subwoofer as
you lower the crossover frequency. So you have to pick a frequency high
enough so that the main speakers don't poop out before the sub takes
over, and the best way to tell that is by listening.

> When I switch the sub on I hear and feel some more air to my mixes. It's
> not that I use it for more bass, but the lower end doesn't sound as thin and
> packed anymore.

Usually, we use "air" to describe an open sounding high end, but you
might be thinking that you feel more air moving, which would be the
case with the subwoofer turned on. I think you're hearing some bass
that you didn't really know was there. That's a good thing, because
after the initial excitement wears off, you might decide that you want
to tame that so as not to rely on it when your mixes are played on a
system that doesn't reproduce those frequencies. Not that they
shouldn't be there, but that without the subwoofer, you should still
get the sense that they ARE there. Remember that some people listen to
music on little speakers attached ot their computer, or even littler
speakers attached to their ears.

> The main thing (among others) for me is that my base drum and the bass
> guitar sound more like a pair to me than two different instruments.

I'm not sure if that's good or bad, but if you think it sounds good,
then it IS good.

I suspect that you don't have any problems.

[Drumsix]

Indeed, I don't have any problems.
I couldn't find the word on my dictonary website, so thanks (learning all
the time).

I understand that the "air" is more for a open sounding high. Maybe a wrong
chosen word. I meant that there's more space in my mixes. Sound is still a
personal choice, so some things are difficult to put in words.

There is no manual on the net for the samson, but you're right about the
connections. However XLR inputs for my output from the mixer and XLR
outputs to my amplifier for the alesis nearfields.

It's not that i hear more or other bass sounds with the sub on, the low end
is more in the right place in the mix.

I'm in the music business for 20 years but mixing and recording is a new
step for me so I'm glad to learn from you and this newsgroup.

Thanks for your time.

Drumsix

"Mike Rivers" > schreef in bericht
oups.com...
>
> Drumsix wrote:
>
>> With your sentence, "It's not a matter of English, it's a colloquialism",
>> it
>> becomes a matter of English (haha). I haven't got a clue what the
>> collo...
>> word means?
>
>>From some dictionary web site or other:
>
> An informal words, or phrase of conversational language that brings
> color to everyday speech and a friendly, conversational tone to
> writing; many are figures of speech that are not meant to be taken
> literally, such as fly off the handle, foot the bill
>
>> As you suggested I played some tracks that in my opinion sounds great
>> (from
>> classical and bigbands to rock (sacd)) and from there on I tweaked the
>> sub
>> for what I thought is the best sound. But with all self adjustments you
>> never know if its the right way as a standard. That's why I posted this
>> question.
>
> There are no standards, but there are some limits. You don't want to
> drive the subwoofer with enough signal so that its amplifier clips. I
> couldn't find a manual for your subwoofer on the Samson web site, but I
> assume it works like most other subs in this class - you feed the left
> and right signal into the subwoofer and that goes through the
> crossover, feeding everything above the crossover out to a pair of
> jacks that go to the main speakers. So you want to set the crossover
> frequency somewhere above the lowest frequency that the main speakers
> can handle, but not so high that the subwoofer can't reproduce
> everything that's sent to it. Anywhere in that range, you'll get all
> the lows, but the'll move from the main speakers to the subwoofer as
> you lower the crossover frequency. So you have to pick a frequency high
> enough so that the main speakers don't poop out before the sub takes
> over, and the best way to tell that is by listening.
>
>> When I switch the sub on I hear and feel some more air to my mixes. It's
>> not that I use it for more bass, but the lower end doesn't sound as thin
>> and
>> packed anymore.
>
> Usually, we use "air" to describe an open sounding high end, but you
> might be thinking that you feel more air moving, which would be the
> case with the subwoofer turned on. I think you're hearing some bass
> that you didn't really know was there. That's a good thing, because
> after the initial excitement wears off, you might decide that you want
> to tame that so as not to rely on it when your mixes are played on a
> system that doesn't reproduce those frequencies. Not that they
> shouldn't be there, but that without the subwoofer, you should still
> get the sense that they ARE there. Remember that some people listen to
> music on little speakers attached ot their computer, or even littler
> speakers attached to their ears.
>
>> The main thing (among others) for me is that my base drum and the bass
>> guitar sound more like a pair to me than two different instruments.
>
> I'm not sure if that's good or bad, but if you think it sounds good,
> then it IS good.
>
> I suspect that you don't have any problems.
>

[Ethan Winer]

six,

> The track that Ethan Winner suggest in an other reply on this subject is
obviously a good one, but is more for a proffesional studio (I think). <

If you're going to the trouble and expense to get a subwoofer in the first
place, it makes sense to also set it up as well as possible! :->) Otherwise,
why even bother with a sub at all?

--Ethan

[Scott Dorsey]

Mike Rivers > wrote:
>Drumsix wrote:
>
>> thanks for your advice. I'm from holland, and my english is not fluent so I
>> don't really know what you mean by "department store" subwoofer.
>
>It's not a matter of English, it's a colloquialism. What I was
>referring to was an inexpensive subwoofer designed to use with a cheap
>home stereo system or computer speakers. Over here, those generally
>sell for $50-100, then there's a pretty big price gap before you get to
>speakers that have reasonably flat frequency response in the 20 to 80
>Hz range.

We call these things "thump boxes." It's usually VERY obvious when you
play a Jaco Pastorius record on the system which you have; if all of the
bass notes sound the same, you don't have a real broadband sub in place.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Drumsix]

"Ethan Winer" <ethanw at ethanwiner dot com> schreef in bericht
...
> six,
>
>> The track that Ethan Winner suggest in an other reply on this subject is
> obviously a good one, but is more for a proffesional studio (I think). <
>
> If you're going to the trouble and expense to get a subwoofer in the first
> place, it makes sense to also set it up as well as possible! :->)
> Otherwise,
> why even bother with a sub at all?
>
> --Ethan
>
>
Ethan,

I fully agree with your statement. That's why I posted the question here.
The spectrum analyzer that I use is a simple one that came with my RME card,
digicheck. As wirtten in your earlier reply it's not of any use for
measuring my room acoustics.
The question is what the use for me in an semi-preffseional evnironment? I
don't have the means to buy an 1Hz spectrum analyzer.
What could you recommend to do the job "as good as its gets?

TIA

Drumsix

[Drumsix]

I understand that Scott,

but we dot not all have the means to buy a studio for instance like Peter
Gabriel.
So you do your best to setup a "home" studio by the means you currently
have.
And with these means you want to sound is as good as possible. And for that
I need some assitance with calibarting the sub.
So any help is welcome.

Dumsix
"Scott Dorsey" > schreef in bericht
...
> Mike Rivers > wrote:
>>Drumsix wrote:
>>
>>> thanks for your advice. I'm from holland, and my english is not fluent
>>> so I
>>> don't really know what you mean by "department store" subwoofer.
>>
>>It's not a matter of English, it's a colloquialism. What I was
>>referring to was an inexpensive subwoofer designed to use with a cheap
>>home stereo system or computer speakers. Over here, those generally
>>sell for $50-100, then there's a pretty big price gap before you get to
>>speakers that have reasonably flat frequency response in the 20 to 80
>>Hz range.
>
> We call these things "thump boxes." It's usually VERY obvious when you
> play a Jaco Pastorius record on the system which you have; if all of the
> bass notes sound the same, you don't have a real broadband sub in place.
> --scott
>
> --
> "C'est un Nagra. C'est suisse, et tres, tres precis."

[Laurence Payne]

On Thu, 31 Aug 2006 11:48:54 +0200, "Drumsix" >
wrote:

>I fully agree with your statement. That's why I posted the question here.
>The spectrum analyzer that I use is a simple one that came with my RME card,
>digicheck. As wirtten in your earlier reply it's not of any use for
>measuring my room acoustics.
>The question is what the use for me in an semi-preffseional evnironment? I
>don't have the means to buy an 1Hz spectrum analyzer.
>What could you recommend to do the job "as good as its gets?

Turn it up until you can hear it. Then turn it down a bit.

[Mike Rivers]

Drumsix wrote:

> And with these means you want to sound is as good as possible. And for that
> I need some assitance with calibarting the sub.
> So any help is welcome.

The way to adjust it so that it sounds as good as possible is to simply
adjust it so that it sounds as good as possible to you with the music
you work with, and in the place where you normally work. There aren't
that many adjustments other than the actual position of the subwoofer
in the room, and that's at least somewhat constrained by the physical
arrangement of the room. You probalby aren't about to rearrange your
whole room to get optimum performance from a $200 subwoofer.

I suspect that what's behind your question is that you don't really
KNOW what sounds good, and you're looking for a tool to tell you how
good it sounds. Unfortunately, there is no such tool that you don't
already have - your own ears, or perhaps the ears of a few friends. It
doesn't hurt to have a couple of other people listen while you move
things around or make adjustments, and take an average of their
comments.

[Scott Dorsey]

Drumsix > wrote:
>I understand that Scott,
>
>but we dot not all have the means to buy a studio for instance like Peter
>Gabriel.
>So you do your best to setup a "home" studio by the means you currently
>have.
>And with these means you want to sound is as good as possible. And for that
>I need some assitance with calibarting the sub.

The problem is that I think the sub you have is a narrowband box, and so
it _cannot_ be calibrated to be flat because that's not what it's designed
to do.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[[email protected]]

Well, what's a good way to choose a sub to purchase?
Just find some quality 2.0 monitors and then get the matching
sub? Do you normally want to stay with the same brand
as the 2.0s?

[Scott Dorsey]

> wrote:
>Well, what's a good way to choose a sub to purchase?
>Just find some quality 2.0 monitors and then get the matching
>sub? Do you normally want to stay with the same brand
>as the 2.0s?

You could do that.

Or you could buy some full range speakers that don't need a sub.

Buy speakers that you like the sound of. If you don't have enough bass
extension with the speakers you like in the room you like, look into various
fixes for that. A subwoofer is one of the possible fixes.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Ethan Winer]

> The question is what the use for me in an semi-preffseional evnironment? I
don't have the means to buy an 1Hz spectrum analyzer. <

You don't have to buy anything. There's a "CD" you can download for free
from my company's web site that plays tones in 1 Hz increments. It takes a
while to run and plot manually! But it's free and is very accurate. Look
here:

www.realtraps.com/test-cd.htm

If you have a computer connected to your system you don't even have to burn
a CD. Just play the MP3 files directly.

--Ethan

[[email protected]]

Scott Dorsey wrote:
> > wrote:
> >Well, what's a good way to choose a sub to purchase?
> >Just find some quality 2.0 monitors and then get the matching
> >sub? Do you normally want to stay with the same brand
> >as the 2.0s?
>
> You could do that.
>
> Or you could buy some full range speakers that don't need a sub.


For nearfield monitors, if you just want to go with 2.0s
(not needing a sub) should a person be looking
at a minimum of 8" woofers?

[Drumsix]

Ethan,

that 's great.
Thanks for the tip.

"Ethan Winer" <ethanw at ethanwiner dot com> schreef in bericht
...
>> The question is what the use for me in an semi-preffseional evnironment?
>> I
> don't have the means to buy an 1Hz spectrum analyzer. <
>
> You don't have to buy anything. There's a "CD" you can download for free
> from my company's web site that plays tones in 1 Hz increments. It takes a
> while to run and plot manually! But it's free and is very accurate. Look
> here:
>
> www.realtraps.com/test-cd.htm
>
> If you have a computer connected to your system you don't even have to
> burn
> a CD. Just play the MP3 files directly.
>
> --Ethan
>
>

[Scott Dorsey]

> wrote:
>Scott Dorsey wrote:
>> > wrote:
>> >Well, what's a good way to choose a sub to purchase?
>> >Just find some quality 2.0 monitors and then get the matching
>> >sub? Do you normally want to stay with the same brand
>> >as the 2.0s?
>>
>> You could do that.
>>
>> Or you could buy some full range speakers that don't need a sub.
>
>For nearfield monitors, if you just want to go with 2.0s
>(not needing a sub) should a person be looking
> at a minimum of 8" woofers?

The size of the woofer doesn't really tell you anything useful. Two speakers
with the same physical woofers but with different cabinet voicing may have
completely different low end.

Also, be aware that even if you're in the near field, room effects are
still very significant on the low end, and the speaker radiation pattern
is still pretty much omnidirectional at low frequencies. So the amount of
actual output you need is going to depend on the size of the room.
---scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Les Cargill]

wrote:

> Scott Dorsey wrote:
>
> wrote:
>>
>>>Well, what's a good way to choose a sub to purchase?
>>>Just find some quality 2.0 monitors and then get the matching
>>>sub? Do you normally want to stay with the same brand
>>>as the 2.0s?
>>
>>You could do that.
>>
>>Or you could buy some full range speakers that don't need a sub.
>
>
>
> For nearfield monitors, if you just want to go with 2.0s
> (not needing a sub) should a person be looking
> at a minimum of 8" woofers?
>


There's no telling what size woofers are best. Really. See
if you can get Thiele-Small parameters for the driver, and
dimensions for the expected cabinet, then use WinISD to estimate
the response.

--
Les Cargill