The Link is to a Article that the forums Speaker Builders with 'time to kill' might like to look into.
I hope there is info available that makes posting it worthwhile.
http://benchmarkmedia.com/blogs/applica ... e=omnisend
Damping Factor Article
#2 Re: Damping Factor Article
Good to see someone run the numbers.
I do recall some people saying that a Zobel filter robs the speaker of "life", and I'm wondering if that's because there would be less output in the high frequencies due to the driver's rising impedance being flattened. A few dB here and there can make quite the difference.
Chris
I do recall some people saying that a Zobel filter robs the speaker of "life", and I'm wondering if that's because there would be less output in the high frequencies due to the driver's rising impedance being flattened. A few dB here and there can make quite the difference.
Chris
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#3 Re: Damping Factor Article
I had a quick run through the article but it didn't look very sophisticated, and it could be accused of being a sales blurb for their cables.
It seems to miss the point that speaker units and their alignments can be under-damped or over-damped. If the amp ( eg. valve amp ) is going to be relatively high output impedance, say 2 ohms, this just adds to the Qes of the speaker parameters. The point being, the choice of drive unit, and loading ( box size, porting, etc ) can be adapted to the output impedance of the amp - it just needs to be included in the software calcs at the start.
It seems to miss the point that speaker units and their alignments can be under-damped or over-damped. If the amp ( eg. valve amp ) is going to be relatively high output impedance, say 2 ohms, this just adds to the Qes of the speaker parameters. The point being, the choice of drive unit, and loading ( box size, porting, etc ) can be adapted to the output impedance of the amp - it just needs to be included in the software calcs at the start.
"Once you find out ... the Circumstances ; then you can go out"
#4 Re: Damping Factor Article
I wrote a response and deleted it as being too harsh - it started as stating the article was "self serving twaddle" and went on from there
Its marketing masquerading as technical and it makes as many specific assumptions that it doesn't detail as the myths it purports to debunk...
Its particularly inappropriate here as the assumption made in the article of ideal voltage source behaviour for the amplifier output impedance and the speaker expected signal source impedance do not apply to 90% of the amplifiers we design and discuss in that these are no global feedback tube designs and particularly the SE ones are better modeled as a current source with finite output impedance... something Scott as speaker designer always takes into account and has mentioned here many times.
This is not meant in any way to be criticism of John for posting it as it lets us raise the issue here and discuss it for all our benefit.
James
Its marketing masquerading as technical and it makes as many specific assumptions that it doesn't detail as the myths it purports to debunk...
Its particularly inappropriate here as the assumption made in the article of ideal voltage source behaviour for the amplifier output impedance and the speaker expected signal source impedance do not apply to 90% of the amplifiers we design and discuss in that these are no global feedback tube designs and particularly the SE ones are better modeled as a current source with finite output impedance... something Scott as speaker designer always takes into account and has mentioned here many times.
This is not meant in any way to be criticism of John for posting it as it lets us raise the issue here and discuss it for all our benefit.
James
#5 Re: Damping Factor Article
+1 to Mark and James....
I went some way to explore this in regard to speaker alignment and loading and demo'd some findings at Owston some time back. The main enlightenment came with the F2 which has v.high o/p impedance which can produce some very bloated bass. I demo'd with a few speakers of increasing loading and the change in bass response was marked...
I'm not sure the results proved anything concrete regarding d/f being good or bad because despite the f2 having high output impedance it can sound superb when coupled with the right speakers....
I went some way to explore this in regard to speaker alignment and loading and demo'd some findings at Owston some time back. The main enlightenment came with the F2 which has v.high o/p impedance which can produce some very bloated bass. I demo'd with a few speakers of increasing loading and the change in bass response was marked...
I'm not sure the results proved anything concrete regarding d/f being good or bad because despite the f2 having high output impedance it can sound superb when coupled with the right speakers....
There's nowhere you can be that isn't where you're meant to be
#6 Re: Damping Factor Article
I'm a Crocodile when it comes to Skin Thickness, I'm not feeling any upset by the Replies .
I'm Glad the Article was shown to be Questionable as to the content, if the Intention of the author was to angle for cable sales, he has not escaped this being revealed on Audio Talk.
I'm Glad the Article was shown to be Questionable as to the content, if the Intention of the author was to angle for cable sales, he has not escaped this being revealed on Audio Talk.
#7 Re: Damping Factor Article
True, but there are effects outside of the Thiele-Small range, which I think this article covers fairly well.
I think we should give the writer more credit - it's a much better piece of work than most HiFi manufacturers would put out.
Chris