Author Topic: Hafler circuit used in SDA Crossover  (Read 12409 times)

SunnyDaze

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Re: Hafler circuit used in SDA Crossover
« Reply #15 on: August 02, 2014, 02:09:11 AM »
Here's some reading for you.

http://www.polkaudio.com/downloads/whitepapers/SDA_WhitePaper.pdf


The link is dead. I found this link on the bottom of the vr3 website and it didn't work from there either.

This thread is making me want to get over to Carl's and check out his Polkage. 

Offline F1nut

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Re: Hafler circuit used in SDA Crossover
« Reply #16 on: August 02, 2014, 02:41:45 AM »
Ah thanks, I didn't realize it was dead.

Try this one, all the white paper info is in there.

http://www.vr3mods.com/uploads/SDA_Handbook_2011_Rev3.pdf

  'Political Correctness'.........defined

"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end."
 

Offline GraphicFX

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Main system
Pre-amp: Adcom GTP-350
Main Amplification: Crown PS-400
Surround Amplification: Crown PS-400
Mains: Polk SDA-2B Studio
Rear fill: Polk RTA-12
Subs: (3) Velodyne F1200b

Offline GraphicFX

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Re: Hafler circuit used in SDA Crossover
« Reply #18 on: August 02, 2014, 07:52:26 AM »
http://www.hifiwigwam.com/showthread.php?18855-quot-Hafler-Surround-Sound-quot-does-it-work-If-so-why-!

Just to clarify things a bit, My Hafler setup is powered by it's own dedicated amp, (Crown PS-400) It works well due to good sound and front mounted pots allowing me to dial in just the right amount of surround volume or none at all. which now is usually the case.

But I'll say it again; Cranking up the surround yeilds very little difference, which is why I started this thread in the first place.

That being said, and this being my thread, how about coming over here and checking out My Polkage
Main system
Pre-amp: Adcom GTP-350
Main Amplification: Crown PS-400
Surround Amplification: Crown PS-400
Mains: Polk SDA-2B Studio
Rear fill: Polk RTA-12
Subs: (3) Velodyne F1200b

Offline GraphicFX

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Re: Hafler circuit used in SDA Crossover
« Reply #19 on: August 02, 2014, 08:00:05 AM »

That being said, and this being my thread, how about coming over here and checking out My Polkage

My Polkage includes Weedage and Beerage
Main system
Pre-amp: Adcom GTP-350
Main Amplification: Crown PS-400
Surround Amplification: Crown PS-400
Mains: Polk SDA-2B Studio
Rear fill: Polk RTA-12
Subs: (3) Velodyne F1200b

SunnyDaze

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Re: Hafler circuit used in SDA Crossover
« Reply #20 on: August 02, 2014, 09:34:27 AM »

That being said, and this being my thread, how about coming over here and checking out My Polkage

My Polkage includes Weedage and Beerage

And minimal discressionage.  :police:

Offline vstarkwell

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Re: Hafler circuit used in SDA Crossover
« Reply #21 on: August 02, 2014, 11:06:11 AM »
Here's some reading for you.

http://www.polkaudio.com/downloads/whitepapers/SDA_WhitePaper.pdf


The link is dead. I found this link on the bottom of the vr3 website and it didn't work from there either.

This thread is making me want to get over to Carl's and check out his Polkage.

Carl's Polks SUCK!!!! as does all his other equipment.  :laugh:

Offline AdamG

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Re: Hafler circuit used in SDA Crossover
« Reply #22 on: August 02, 2014, 11:13:29 AM »
The polks have a very low impedance, so it may be sending less signal to the rears than a standard load.

Offline schwarcw

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Re: Hafler circuit used in SDA Crossover
« Reply #23 on: August 02, 2014, 11:41:50 AM »

Carl's Polks SUCK!!!! as does all his other equipment.  :laugh:

I know, I am tone deaf to knowing what is good and bad sound!
Carl

SunnyDaze

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Re: Hafler circuit used in SDA Crossover
« Reply #24 on: August 02, 2014, 11:48:32 AM »

Carl's Polks SUCK!!!! as does all his other equipment.  :laugh:

I know, I am tone deaf to knowing what is good and bad sound!

I think you're confusing yourself with me, Carl.

Offline GraphicFX

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Re: Hafler circuit used in SDA Crossover
« Reply #25 on: August 02, 2014, 12:49:41 PM »
The polks have a very low impedance, so it may be sending less signal to the rears than a standard load.

Nothing is sent to the rears except for the original source material. They are on their own dedicated amp.
Main system
Pre-amp: Adcom GTP-350
Main Amplification: Crown PS-400
Surround Amplification: Crown PS-400
Mains: Polk SDA-2B Studio
Rear fill: Polk RTA-12
Subs: (3) Velodyne F1200b

Offline GraphicFX

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Re: Hafler circuit used in SDA Crossover
« Reply #26 on: August 03, 2014, 09:16:53 AM »
I have still not gotten a definitive answer. so I will ask the question again.

My surrounds (on it's own dedicated amp) running through a Hafler Circuit, even at high volumes barely change the overall sound of music especially during passages where there is a large stereo effect ie; Old stereo beatles recordings, leads me to believe that the hafler surround Information is very similar to the SDA information coming from the mains.

Is Polk using some variation of the Hafler Principle?
Main system
Pre-amp: Adcom GTP-350
Main Amplification: Crown PS-400
Surround Amplification: Crown PS-400
Mains: Polk SDA-2B Studio
Rear fill: Polk RTA-12
Subs: (3) Velodyne F1200b

Offline F1nut

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Re: Hafler circuit used in SDA Crossover
« Reply #27 on: August 03, 2014, 01:34:41 PM »
Quote
  I have still not gotten a definitive answer   

Yes, you did.
  'Political Correctness'.........defined

"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end."
 

Offline schwarcw

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Re: Hafler circuit used in SDA Crossover
« Reply #28 on: August 03, 2014, 02:26:19 PM »
I have still not gotten a definitive answer. so I will ask the question again.

Is Polk using some variation of the Hafler Principle?

GFX,

Jesse's reference to the SDA white paper should explain it in detail.  In short, NO.  Matthew Polk patented his SDA technology which is intranural crosstalk cancellation.  Forget anything Hafler when it comes to the Polk SDA.  No common denominator at all.

Enjoy your SDAs.  They are a wonderful speaker that have a signature sound all their own.

Regards,
Carl

Offline polkman

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Re: Hafler circuit used in SDA Crossover
« Reply #29 on: October 27, 2018, 08:55:01 PM »
What do you mean, "surround info"?

I have surround channels which use a hafler circuit.  My question is the following:
does polk use some sort of version of the Hafler Circuit via the IC and the SDA drivers?

Yes it is pretty much the same as the hafler circuit in that is uses the "Difference signal" culled from the positive terminals of both channels, (through the IC wire) but differs in that it places the surround speakers (SDA effect speakers in Polks case) a designated spacing from the main drivers, and employs a low pass filter of approximately 150 Hz, to allow the SDA effect speakers to reproduce bass in addition to the Primary drivers.

Therefore it is very similar but merely different in implementation.
Instead of rear "Surround" speakers, the polks place them next to the main drivers to create a wider pseudo soundstage, as where the Hafler circuit creates a pseudo surround sound and a larger overall room image to the rear mostly.