Frequency Response

**TJVV** · 10-18-2005 05:54 PM

Polk Staff:

I'm setting up a lab system and am interested in employing numerous RM6751 satelite speakers. Before I can puchase I need to get a picture of thier frequency response (db as a function of frequency) characteristics. I have not been able to locate this material online. Could you let me know where to find it, or reply with an image of such documentation?

I need a frequency response profile for the RM6751 satelite speakers.

Thanks for your time,
TJVV

**AsSiMiLaTeD** · 10-18-2005 06:21 PM

If I understand correctly, you're wanting a plotline of db readout at varying frequencies, correct?

I don't know if Polk is going to publish something like that. The main issue that you'll run into is those numbers can vary quite a bit based on things like placement, room acoustics, equalization, and even the equipment you have pushing them.

Now if you're just looking for a frequency range, that's easier...but the frequency curve is what it sound to me that you're looking for...

**mldennison** · 10-18-2005 06:44 PM

you might want to try the archives of some magizines, something like home theater or sound and vision, they ussually publish frequency responses of the speakers they review. dont think i have ever seen the RM6751 satelite's reviewd though.

**Dennis Gardner** · 10-18-2005 07:43 PM

Strange request, I never thought of decorating with frequency plots. What a novel idea. :D

**F1nut** · 10-18-2005 07:59 PM

Originally Posted by TJVV

I need a frequency response profile for the RM6751 satelite speakers.

That isn't going to happen.

**TJVV** · 10-18-2005 09:05 PM

Polkmaniac:
“If I understand correctly, you're wanting a plotline of db readout at varying frequencies, correct?”
YES, you are correct.

( F1nut ) Why would a reputable manufacturer not make this available. I understand that a speaker might “sound good”, but the proof is in the plot. Yes, that plot may be modified by the driver and environment, but I’m simply concerned with a ‘neutral’ environment baseline. (Acoustic tech’s often acquire baseline measures in an anechoic chamber.) One does not engineer and develop a sound source without taking into account the designs frequency response profile. In fact, one might presume that sound sources are engineered to produce a specifically desired frequency response, based on relevant psychoacoustics and their intended environment of employment. We know that Polk Audio has the numbers and the plots. The question becomes “is the plot respectable enough that they’re willing to share it?” I’m hoping that it is, and I’m hoping that they will.

Worst case scenario, I can always buy a set, plot the curve myself and return them if they’re not suitable for my purpose. I’d rather not have to go through that bother on the front end. Rather, I’m hoping that Polk will assist me as I go about selecting the product best suited to my needs. We’ll see.

Cheers,
TJVV

**Tritonman** · 10-18-2005 09:17 PM

I'm having deja vu.

**F1nut** · 10-18-2005 10:11 PM

Originally Posted by TJVV

Why would a reputable manufacturer not make this available.

Gee I don't know, trade secret maybe? Why don't you try asking GM for a copy of their engine mapping for the Corvette!?!

**TroyD** · 10-18-2005 10:18 PM

One, it's proprietary information. I doubt there are any companies that will give out this info.

Two, it's basically worthless.

Three, what's with all the Inspector Gadget types of late?

BDT

**Dennis Gardner** · 10-18-2005 10:24 PM

I simply don't understand the request.......maybe I'm dense. The 6750 is a sub/sat system that can't have an accurate frequency graph unless the placement is extrememly controlled. A powered sub placement and balance with sats has everything to do with how "flat" the curve is, let alone room acoustics.

I'm not trying to be smart assed, but I may be missing your concern. I do understand trying to get a set of speakers that are known to be "accurate" across the frequency range, if that is what you are trying to achieve, but unless your "lab system" is anechoic itself, what good is it?

Help me by clarifying yourself, if we missed your point.

**Dennis Gardner** · 10-18-2005 10:27 PM

Originally Posted by TroyD

what's with all the Inspector Gadget types of late?

BDT

My guess is college is back in session and all the cute girls haven't gotten tired of the football team yet.

Second semester is alot more settled.

**TJVV** · 10-19-2005 02:17 PM

Sorry guys, I thought I was posting a question to an advanced technical forum on speakers.
Thank you Polk Maniac and Dennis Gardner for your thoughtful responses.

For those contributing to the discussion that appear to know decidedly little about frequency response profiles, a ‘little’ research on your part would reveal that many manufacturers do in fact make them available. Some do not provide a graphic representation of such, but choose rather to express that the frequency response is, for example, 30 Hz - 24 kHz [range] +/-3 dB [variance within that range]. This is meaningful information (if you understand it) and is clearly not a proprietary secret, as any body with a spectrum analyzer can get it.

**PolkThug** · 10-19-2005 02:26 PM

Hi TJVV,

The 6750's (which I assume is like the 6751)lower -3dB limit is 45Hz and the upper -3db limit is 20khz.

If you want a flatter freq response you'll probably need to spend more $.

Hope this helps,
PT

**Willow** · 10-19-2005 02:27 PM

http://www.polkaudio.com/homeaudio/s...creens/rm6750/

**madmax** · 10-19-2005 02:28 PM

Originally Posted by TJVV

Sorry guys, I thought I was posting a question to an advanced technical forum on speakers.

Oh, well that's the problem, Duh. The forum you are posting on is the Polk audio forum.

madmax

**TroyD** · 10-19-2005 02:41 PM

Yup, you are definately a putz. My magic 8-ball says that your stay will be short lived.

I was under the impression he was looking for a graph with the performance over the entire frequency band as opposed to just overall FR limits. My fault for not consulting my Gadget Decoder Ring.

BDT

**jdhdiggs** · 10-19-2005 02:42 PM

To be helpful: Those are some of the lowest, if not the lowest, end speakers polk makes. Without the sub, you'll be lucky if they dig down to 120Hz with any volume. If you are really looking for flat speakers for a lab environement, look elsewhere (or up the product line) From your attitude, I would care to guess that the LSi15 would be the least expensive speaker in the Polk lineup.

Also, those graphs change with the power supplied. Typically they are graphed at near 1W, but for dynamic response the graphs can shift an move. For a cabinet as small as the one you are looking at, these fluctuations will be very significant.

If you want to get more info, I would suggest losing the attitude. After all, you are the one asking for the frequency responses on a satellite system which just seems

**Tritonman** · 10-19-2005 02:58 PM

hrmm..this question reminds me of this particular post...

http://www.polkaudio.com/forums/showthread.php?t=32598

**F1nut** · 10-19-2005 06:33 PM

I gave you two very thoughtful responses, you just didn't like the answers.

Well, seeing as I'm such a great guy I looked around and found this "graph" for you, which I know will answer all your questions.

**bknauss** · 10-19-2005 09:40 PM

What kind of response do you want? 1M? Ground plane? Infinite baffle?

**Kenneth Swauger** · 10-20-2005 01:43 PM

Hello TJVV,
I have the information you have requested, via email, however my responses have been sent back as "undeliverable". Can you provide another email address?
Regards, Ken

**ND13** · 10-20-2005 01:46 PM

Ken is"DA MAN"

**scottnbnj** · 10-20-2005 02:02 PM

anyone notice the temperature is dropping? it's like a thousand degrees colder than when i went out to get the paper this morning.

)

**ND13** · 10-20-2005 02:10 PM

Uh oh, it's gonna be like that move....."The Day After Tommorrow" :D

**steveinaz** · 10-20-2005 02:19 PM

Some of you need to get laid. The guy just asked for a frequency plot of a speaker and now he's a troll.

sheesh....give it a frickin break. This unrelenting "pounding" of new people lately is out of control.

**jdhdiggs** · 10-20-2005 02:40 PM

Originally Posted by TJVV

Sorry guys, I thought I was posting a question to an advanced technical forum on speakers.

Steve, I think this is what riled up the masses the most. Most people were giving him good info until then.

And yes, I think some telling someone else that a freq-response graph is usually worthless is good info.

**AsSiMiLaTeD** · 10-20-2005 02:41 PM

Originally Posted by steveinaz

Some of you need to get laid. The guy just asked for a frequency plot of a speaker and now he's a troll.

sheesh....give it a frickin break. This unrelenting "pounding" of new people lately is out of control.

I agree, looks like Ken is gonna hook him up anyway, so all is well...

**F1nut** · 10-20-2005 04:30 PM

Ken, don't feed the troll.

**AsSiMiLaTeD** · 10-20-2005 04:44 PM

Jesse, do you have some insight or inside information you'd like to share with the rest of us?

To me, this is just a guy wanting some information on Polk speakers, but I'm naive that way, so if you know something to the contrary, let us know...

Cheers,

**F1nut** · 10-20-2005 07:51 PM

PM,

You just have to read between the lines. The very first clue are the speakers in question. Nobody buying those speakers (Polk's BOTL) is going to give a rat's south end about a frequency graph.

ATB,
The Grumpy Troll Hunter

Thread: Frequency Response

Thread Tools

Frequency Response

Thread Information

Users Browsing this Thread

Posting Permissions