Extraordinary claims made about Rythmik Subwoofer !!

[pjpoes]

Hey don't take it personally, I don't like what Snoopy has been doing here, I'm just saying, I think this was a servo sub. The person who tested it appears to have owned it, he claims it was a servo sub, and there is nothing about its features that suggest otherwise. The only mention of an eq feature I saw was the dampening extension switches, which are available on both the LT and Servo units.

[Cloth Ears]

Originally posted by snoopy
Where in the original papers by Thiele and Small is there any emphasis on the analysis of a loudspeaker enclosure by listening to it ?? Can you explain how Theile or Small derived the small signal electro acoustical system response function by listening to various different speaker systems ??

To really understand the details in Thiele or Small's papers requires understanding of engineering circuit analysis and the dynamics of mechanical and acoustical systems. To say otherwise is just displaying your ignorance.

Where in my post did I say that they listened to the speaker drivers for the purposes of writing their various papers? They "listened" to their lecturers and teachers and to the wisdom of those who came before them (Rice, Kellogg, Thuras, Beranek and especially Novak in the case of Theile, and all of these plus Benson in the case of Small). They learned from these people and their papers.

You deliberately misunderstand any post that doesn't agree with your stated position and then attempt to denigrate that person from an incorrect position.

In answer to your post:

Originally posted by snoopy
No the question should be "Is it fair to use highly exaggerated or false claims to disadvantage the competition in order to sell your own products ??"

No. It is not fair to use claims of this type in order to sell your products. And, if you read the Rythmik site with an unbiased eye you will see that this is not the case. Almost every seller of parts for speakers does not benefit from this type of advertising hyperbole, as the people who buy their products use them to make real products (see also PHL, SEAS, Scanspeak, etc).

The hyperbole comes from end-product manufacturers (see anyone selling a pair of speaker cables or interconnects for over $5000 per pair). A person selling the parts for a subwoofer for under $500 is not in this category at all.

[mbutzkies]

pjpoes, Infinia

It is my impression that Ikkla tested the servo system.

Ikkla seems technically competent, and he claims it was the servo version. F3 and damping options are available to both the servo and LT system.

I believe the Rythmik system uses both a sensing coil and a resistor for the servo. Since it is a diy kit, he needed to attach wiring to the sensing coil.

I would have liked to seen Ikkla test the system with and without the servo though.

[snoopy]

Originally posted by infinia
Hi
The sub as tested Did Not use the servo feedback loop to reduce distortion. The one he tested used the Linkwitz Transform circuit only.
Quote from the Rythmic web site
"The kit consists of a 370w amp (A370 SE) with a Linkwitz transform circuit a board, and a DS12 driver without servo feedback. With the Linkwitz Transform circuit we can get a better bass extension than what natural physics gives us. "


The LT circuit places great demands on excursion and amplifier power (ie potentially higher IMD) and trading this for a limited amount of frequency extension.


Besides it's normal for marketing to make broad sweeping statements or puffery of their products. You cannot use these statements in a technical argument unless lawyers are involved.

Cease fire now folks, hahaha.

That is totally absurd !! What would a lawyer know about technical issues anyway This issue could have easily been resolved by the manufacturer right from the start

Why use a Linkwitz transform when a properly designed servo could be use to extend the frequency response and to reduce distortion as well !!

Also it's not normal for marketing to make false and exaggerated claims about a product unless they are trying to profit out of peoples ignorance

[snoopy]

Originally posted by Cloth Ears


The hyperbole comes from end-product manufacturers (see anyone selling a pair of speaker cables or interconnects for over $5000 per pair). A person selling the parts for a subwoofer for under $500 is not in this category at all.

It doesn't make any difference what price something is. There are many people that have been scammed by low cost items which weren't fit for their intended purpose or didn't meet the advertisers claims.

Like I said before there has been an exaggerated claim made for this subwoofer which has been contradicted by the test results from an independent tester.

Now either back up this claim or have it removed from the website !!

Alternatively if you don't agree with these test results then please provide alternative test results and state the conditions under which they were made.

[barfind]

Go here if you really want to get more info on this sub. Engage here, and you will get the owner involved, and his uses, and his distributors



http://www.audiocircle.com/circles/i...?topic=47310.0

[snoopy]

Originally posted by mbutzkies
pjpoes, Infinia

It is my impression that Ikkla tested the servo system.

Ikkla seems technically competent, and he claims it was the servo version. F3 and damping options are available to both the servo and LT system.

I believe the Rythmik system uses both a sensing coil and a resistor for the servo. Since it is a diy kit, he needed to attach wiring to the sensing coil.

I would have liked to seen Ikkla test the system with and without the servo though.

Yes that would have been very interesting

[snoopy]

Originally posted by barfind
Go here if you really want to get more info on this sub. Engage here, and you will get the owner involved, and his uses, and his distributors

http://www.audiocircle.com/circles/i...?topic=47310.0

These new subs will be utilizing Brian's patented Direct Servo technology.

Does anyone know the actual patent number ??

That's if one actually exists

[barfind]

Again go to the AC thread if you really want more info. Why dont you ask all your questions there. You WILL get a response from the owner of Rythmik

[snoopy]

Originally posted by barfind
Again go to the AC thread if you really want more info. Why dont you ask all your questions there. You WILL get a response from the owner of Rythmik

I've got a better idea, since you are a member of that forum why don't you ask on our behalf Alternatively ask him to come here and to kindly resolve the issue as I believe he is already a member of this forum. That would save having to re-register on another forum just to ask a simple question

Aren't you interested in finding out as well ??