SMS-1 EQ pic

[mike c]

holy crap!

denon pre-pro and amp
dual fathoms
focal be's!

very nice!

 

[Warpdrv]

Very nice room and equipment you have there Frank.....

Take a moment to hook them up as master and slave and run ARO, and see if you notice any changes by ear.... seeing where you have the subs placed, I'm sure the installer probably just set phase on both to 0.... Otherwise take notes of the settings for future benefit. So little should change with running the ARO as Master/Slave.

Thankfully the ARO only takes a minute or so to run, which makes it very easy to experiment... I assume that you have a SPL meter.

 

[Franin]

Thanks guys, No he has them both at 45 degrees. Thats where he forund them to match. Have to say thats where they worked well. Mind you looking forward in looking at the room graph to see how it looks.

 

[Franin]

Could someone please explain to me like you will explain to a 2 year old on what Q is and how to avoid stacking. Im trying to get a good understanding of it. Im dumber than a caveman at the moment.

 

[Warpdrv]

Frank, If you look at the picture above, you can see where I have the 2 EQ sliders between 40 and 50hz pretty close together... this is what they are referring to as "Stacking". With the manual setup, you have the ability to not only adjust the EQ up and down, but you can also place/move the slider anywhere you want throughout the Freq. Range. to increase or decrease and isolate a particular freq..

Stacking will help you tame or bump that certain freq with a little more gusto if you will by using 2 or more sliders at a specific Freq. Please remember that it is much better to decrease or cut freq.'s to attain a flat response rather then boost them, as boosting will start to introduce unwanted distortion into the chain. I know that is spelled out in that Outlaw guide that I linked for you..

What my response is showing is that I am boosting to get a flat response far more then I should have been, which is not the proper way to do it, and is not how I have mine set now, but sometimes it is required. Boosting is OK, but as the manual suggests, don't add too much.

 

[Franin]

Warp,

Good show! Add me to the list of drooling jealous-ites.

Frank, If you look at the picture above, you can see where I have the 2 EQ sliders between 40 and 50hz pretty close together... this is what they are referring to as "Stacking". With the manual setup, you have the ability to not only adjust the EQ up and down, but you can also place/move the slider anywhere you want throughout the Freq. Range. to increase or decrease and isolate a particular freq..

Stacking will help you tame or bump that certain freq with a little more gusto if you will by using 2 or more sliders at a specific Freq. Please remember that it is much better to decrease or cut freq.'s to attain a flat response rather then boost them, as boosting will start to introduce unwanted distortion into the chain. I know that is spelled out in that Outlaw guide that I linked for you..

What my response is showing is that I am boosting to get a flat response far more then I should have been, which is not the proper way to do it, and is not how I have mine set now, but sometimes it is required. Boosting is OK, but as the manual suggests, don't add too much.

Thankyou so much for that. I can't believe you can actually move the slider, thats what they were talking about having the Hz closer together I could not under stand how was that possible. What is Q?

How Do you subs go with that boost? Are they handling it well? Sorry for the questions but I really want to get a good understanding before i dive in and make a mess of things.

 

[Warpdrv]

Thankyou so much for that. I can't believe you can actually move the slider, thats what they were talking about having the Hz closer together I could not under stand how was that possible. What is Q?

How Do you subs go with that boost? Are they handling it well? Sorry for the questions but I really want to get a good understanding before i dive in and make a mess of things.

As I have said before, those were old measurements and I have changed things in my equipment list since then as well as having a better understanding of the do's and don'ts of this hobby, I no longer have boosts like those that high in my config.

What is Q?

Remember that Q is based on how the speaker is designed, with driver parameters, box size and design construction. This is unchangeable for the JL F112, as the box is already built. These are all the things JL had to consider when building the Sub.
It it basically a measurement of how the driver responds in different design box parameters.

Please excuse me, I am not very well versed with defining Q as others that are better educated in this department... but I will link you to a site that is better at explaining all that. Cut and pasted from here.... http://www.bcae1.com/spboxad2.htm I just searched google for "what is speaker Q" plenty of hits

Vas
Vas is the volume of air that has the same compliance as the speaker's suspension. Stiff speakers have lower Vas and tend to use small enclosures. Speakers with loose suspension have a higher Vas and use larger enclosures.

Qes
Qes is the electrical Q of the speaker and only takes the electrical properties into consideration.

Qms
Qms is the mechanical Q of the speaker and only takes the speaker's mechanical properties into consideration.

Qts
Qts is the total Q of the speaker. It is defined as 1/Qts = 1/Qes + 1/Qms.

Qtc
Qtc is the total Q of the speaker in an enclosure including all system resistances. A Qtc of .707 is the most common and generally produces the flattest frequency response with approximately a 6dB/octave rolloff. Higher values of Qtc will give a peak in the output with a sharper rolloff. A lower Qtc will start to roll off earlier and will roll off at a slower rate. If you don't know what Qtc you need, start with a Qtc of .707.

Violet = Qtc: 0.9; Green = Qtc: 0.8; Red = Qtc: 0.7; Yellow = Qtc: 0.6; Cyan = Qtc: 0.5;

 

[avaserfi]

In this context (equalization) Q or quality factor refers to the size of the frequency range effected by a specific band. The larger the Q the more narrow the frequency. This means a Q of 50 will effect a much smaller number of frequencies than a Q of 0.5.

The Q of a band is adjustable on the SMS-1.

Here is an example of modeled equalization:

Gray is no EQ
Blue is Q = 0.5
Yellow is Q = 50

Each equalization is a 6dB increase at 70Hz.

 

[Davemcc]

Or to put what averserfi said in kindergarten terms, Q is how wide or how narrow an adjustment you make. To emphasize, both the yellow and blue lines represent an identical 6 dB adjustment. The only difference is Q. With the SMS-1, you can move the sliders to select the center frequency of your adjustment, in this case 70Hz. Then you can also adjust the Q to either spread out or closely define the range of your adjusment from that slider's center point.

 

[Warpdrv]

Oh for cryin out loud, I totally forgot about they used a measurement of Q regarding the width or how narrow of the freq that you are adjusting that is being effected.......


Darnit, all that info and typing for nothin.... DOH... I am just dumb... Totally ranting about something irrelevant to what you were asking about...

 

[Franin]

Thanks Guys so in my understanding(let me have a go) in that situation it's best to have a Q=50 so you use less freq to bring down that peak. In that case with the SMS-1 you will only have one slider to bring down that peak vs the the blue one which you will require a few sliders to bring that peak down. Being that it's only 8 band you really don't have that much to spare.

Oh for cryin out loud, I totally forgot about they used a measurement of Q regarding the width or how narrow of the freq that you are adjusting that is being effected.......


Darnit, all that info and typing for nothin.... DOH... I am just dumb... Totally ranting about something irrelevant to what you were asking about...

Mate thanks regardless, if you think your dumb look at the questions im asking

 

[mike c]

this might help
http://www.audioholics.com/reviews/acoustics/velodyne-sms-1-subwoofer-parametric-eq-system

then ignore the velodyne manual and use this:
http://pdf.outlawaudio.com/outlaw/docs/sms1guide.pdf

oh and make sure you set the crossover on the SMS-1 to off if you are already using the LFE output on your pre-pro

 

[Franin]

this might help
http://www.audioholics.com/reviews/acoustics/velodyne-sms-1-subwoofer-parametric-eq-system

then ignore the velodyne manual and use this:
http://pdf.outlawaudio.com/outlaw/docs/sms1guide.pdf

oh and make sure you set the crossover on the SMS-1 to off if you are already using the LFE output on your pre-pro

Thanks Mike, I have the outlaw sms1 guide and thanks for the tip regarding the crossover.

BTW guys after using the SMS with your subs how much change have you noticed? Is it a night and day difference?

 

[Davemcc]

BTW guys after using the SMS with your subs how much change have you noticed? Is it a night and day difference?

Before:

After:

It is a very significant improvement.

 

[Franin]

Before:

After:

It is a very significant improvement.

That looks good.

 

[croseiv]

That's pretty flat there!

 

[Alex2507]

That's pretty flat there!

Yes it is and I'm pretty jealous.
He's got a Corvette too!
And an Integra.

Dave's one of my heroes.

 

[tcarcio]

Dave that looks great and with very little boost in freq's anywhere. I also have the sms and I love it but it took me awhile to get everything right so I could get that type of response in my HTR. Alot of moving things around and some acoustic treatments that helped out tremendously. I could get a pretty good response but I had to do alot of boosting of freq's and we know that isn't good and really doesn't make the sound much better. I always say that if your adjustments look more like a smile then a frown you will smile even more, if you get what I mean.......

 

[Davemcc]

Yes it is and I'm pretty jealous.
He's got a Corvette too!
And an Integra.

Dave's one of my heroes.

Thanks for saying that but it's all just a matter of priorities. I've actually got a small, inexpensive house on the wrong side of town with a small mortgage. The actual room I have to use is probably one of the worst rooms you could imagine for HT. It's small (11 x 14), has 4 doorways in inconvenient locations and a picture window. With the Audessey, SMS-1 and some room treatments, I've managed to make it somewhat passable for HT.

But I do loves me my toys.

Dave that looks great and with very little boost in freq's anywhere.

Thanks, but if you look at the before graph you see that my room produces just one large peak for the entirety of the bass frequencies centered around 40Hz. My biggest issue is actually getting enough dB cut. The before pic was taken after the SMS-1's auto-calibration. IIRC, when I measured the system using a hand-held SPL with no calibration with the sub in the other corner of the room, I measured something like a 38dB peak at 40Hz.

 

[Warpdrv]

Sure is nice when it all comes together like that did Dave.... that was a monstrous peak ya had there buddy....


Frank take note.... when you cut a bunch of freq's to level things off in your room you will lower the output of your sub, but intern you can increase the gain on the sub output, or output level of the SMS as well to compensate.

Dual subs will help alot in balancing the bass in your room, which usually makes it easier to work with the EQ.