Yes.
And this in phase back pressure that keeps the other driver from moving half as much is out of phase with the mid range frequencies.<<<
That would still apply, good sound or distorted.
Although this is more of a passive problem rather then active.
Again, a different issue or topic here, what that little bit of midrange does to the bass pales in comparison to what the bass will do to the midrange sharing the same enclosure.
Hi,
Its all still pretty much nonsense.There is no excess of bass to modulate
anything, in theory or in practice, it makes no significant difference. But
you are free to use separate enclosures if you like, but you will have
less airspace to damp the midrange rear wave, maybe a factor,
maybe not, also will effect possible MLTL effects in tall thin boxes.
No real distortion differences : Zaph|Audio
rgds, sreten.
*"simple linear theory" is just that. It does not even brush the compounding of evanescent acoustic waves.*
Pretentious ? Moi ? Pray tell what theory that isn't linear "compounds evanescent acoustic waves" .......
Its all still pretty much nonsense.There is no excess of bass to modulate
anything, in theory or in practice, it makes no significant difference. But
you are free to use separate enclosures if you like, but you will have
less airspace to damp the midrange rear wave, maybe a factor,
maybe not, also will effect possible MLTL effects in tall thin boxes.
No real distortion differences : Zaph|Audio
rgds, sreten.
*"simple linear theory" is just that. It does not even brush the compounding of evanescent acoustic waves.*
Pretentious ? Moi ? Pray tell what theory that isn't linear "compounds evanescent acoustic waves" .......
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Alvis, there are many x.5 way speakers where the drivers share a single enclosure, including the JBL Everest I referenced above. "Muddy" and "distorted" are not adjectives one normally uses referring to the Everest. There are many other fine-sounding speakers that might be exampled. Your theory simply does not agree with reality.
You've taken my comment out of context to support your side of the argument, but in fact it doesn't.
The fact that the two drivers are pushing equally against each other in the bass frequencies is why they do NOT modulate each other. The cone excursion of each driver is virtually identical to what it would be if there was a partition dividing the enclosure in half.
Case closed.
Huh ? How can bass be "out of phase with the mid range frequencies". That is a non sensical statement in the context of what is being discussed.
But the original posters question is whether the two drivers should be in the same enclosure or not, so I think my point is relevant. There may be more midrange leakage through the woofer cone in the shared cavity approach, but its a minor point.
Excess bass SPL relative to the mid range for a desired flat response.
It's completely different. In a regular 2 way the tweeter would be isolated.
So s single driver in a single box is free to do as it may, it always has a STATIC SUSPENSION. The single driver is controlled by a single electrical signal, it does not have it's cabinet pressure enhanced or augmented by another driver playing an unequal frequency.
Complete nonsense.The cabinet back pressure from the second driver will cause the driver producing both midrange and bass to have half the excursion that it would otherwise need if it was the only driver in the box producing bass.
So basically your saying the mid range will work in two different environments depending on weather or not the <200Hz bass is playing, Thank you.
Maybe if it was even close to a linear reduction.
It's called a "sine wave".
Read post number 4 on mixing sine waves.
http://www.unikanihitode.net/archive/justnet/phonetics/sin.html
Whats with the bass, it's been stated many times that the bass is in balance.
The mid range is not. The "bass only" driver is viewed as an outside influence to the mid range frequencies of the other driver.
Not to be picky, but the article you linked to does not actually support your position or even address the issue at all. Zaph is not comparing a 2.5 way with a partition to a 2.5 way without a partition.
In both cases the woofers share the complete enclosure. He's comparing wiring the drivers in parallel and applying conventional baffle step correction, (not 2.5 way) versus running one driver full range and the other with a low cut-off frequency, eg a 2.5 (well, 1.5) way approach.
So I don't really see the relevance of this article to the discussion...
Hi,
FWIW Alvis's Avator is a character from a UK radio show, Karl Pilkington.
though the radio show is known as the "The Ricky Gervias Show".
The Ricky Gervais Show - Wikipedia, the free encyclopedia
"over the years Karl's role on the show became more prominent as Ricky
and Steve were finding more amusement with his views and personal life."
If there is some intentional irony here its not very funny. Personal intransigent
opinions on technical subjects never are, they never explore the real subject.
rgds, sreten.
FWIW Alvis's Avator is a character from a UK radio show, Karl Pilkington.
though the radio show is known as the "The Ricky Gervias Show".
The Ricky Gervais Show - Wikipedia, the free encyclopedia
"over the years Karl's role on the show became more prominent as Ricky
and Steve were finding more amusement with his views and personal life."
If there is some intentional irony here its not very funny. Personal intransigent
opinions on technical subjects never are, they never explore the real subject.
rgds, sreten.
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Hi,
FWIW Alvis's Avator is a character from a UK radio show, Karl Pilkington.
though the radio show is known as the "The Ricky Gervias Show".
The Ricky Gervais Show - Wikipedia, the free encyclopedia
"over the years Karl's role on the show became more prominent as Ricky
and Steve were finding more amusement with his views and personal life."
If there is some intentional irony here its not very funny. Personal
intransigent opinions on technical subjects never is, its boring.
rgds, sreten.
After a while, I did consider that we were indeed being trolled.
You asked a question, I answered, that's in context.
They are not pushing equally against each other, the cone excursions are not identical at all.
Use your oscilloscope.
It's impossible for different frequencies to be in phase with each other.
I'm not saying what he should or should not do, I'm just saying there is an effect, do with it what you may.
What's with the personal attacks?
I feel I am being trolled with all these nonsense arguments you guys come up with.
Hi,
FWIW Alvis's Avator is a character from a UK radio show, Karl Pilkington.
though the radio show is known as the "The Ricky Gervias Show".
The Ricky Gervais Show - Wikipedia, the free encyclopedia
"over the years Karl's role on the show became more prominent as Ricky
and Steve were finding more amusement with his views and personal life."
If there is some intentional irony here its not very funny. Personal intransigent
opinions on technical subjects never are, they never explore the real subject.
rgds, sreten.
I don't see what my avatar possibly has to do with conversation.
Can't you gracefully walk away?
You mean your second last post about the Everest speakers?
Here's what 2 seconds of googling came up with.
"They lack finesse, sibilants are emphasised, the high notes can be too sharp, the tempo is too fast and the images are much larger than life."
I kid you not.
If its the bass SPL that's required for a flat response, how is it "excess" ? Baffle step means we need to increase the bass in the near-field to get a flat response in the far field. We can either do that in the network, or we can use a 2.5 way system to do it more simply.
Easy baffle step correction is one of the major plus points for a 2.5 way system.
Tweeters are not relavant to the discussion - 2 ways and 2.5 ways both have isolated tweeters. Focus on the bass and midrange only.
Another unequal frequency ? Where is the unequal frequency coming from ? If you have 100Hz and 1Khz being sent to the speaker at the same time, both drivers are seeing 100Hz but only one driver is seeing 1Khz.
The midrange producing driver is not receiving anything as back pressure from the other driver which it is not also being driven equally with itself.
Nope, I said nothing of the sort.
And what exactly does a "linear" reduction mean ?
Thanks for the lesson on how to add sine-waves together, but my comment apparently flew right over your head - there is no significant phase shift between the woofers at bass frequencies because the box is small enough that its operating in the pressurisation region at frequencies where both drivers are operating.
That means that the sine waves of the two woofers bass always "line up".
It's really quite simple.
Compare one mid-bass driver in a 2 way, with a 2.5 way system where there is a 3rd driver producing only the bass.
The bass excursion of the driver producing midrange is now halved, midrange quality will improve due to less bass/midrange modulation effects, not worsen. (It's not as good as going to a full 3 way though)
It's really basic, simple stuff, you really do need to give it up.
Hi,
Well you'd really have to take up the issue with him not me.
Its very clear he is assuming a partition would make next to no
difference whatsoever when both drivers receive the same signal.
And he's looking for some anomalies which he did not find, when
both drivers don't receive the same signal, both in the same box.
There is no rigour in saying a test is not relevant when it is.
You think partitioning the first case would change anything ?
rgds, sreten.
But if you actually performed the math exercise I linked you would find that a 100Hz + 1KHz sine wave looks completely different then 1KHz.
Apparently what I said flew over your head.
When musical instruments are recorded, the instruments are all out of phase with each other. A drum does not vibrate, nor does it have the same peaks in time as a guitar, they are independent of phase and frequency.
This is not about woofer to woofer phase, it's bandwidths being out of phase.
Thanks yet another helpful and informative post from Srten.
I guess your must have an affinity for getting your way around here. lol.
Alright things are getting nasty, have a good day folks.
Well, I read the article and both the title and his conclusion at the end are inconsistent with the actual testing he performed. He tested one thing and arrived at conclusions on something else. (Not the first time Zaph's conclusions don't seem to connect to the main body of his articles either...)
So I would not have chosen that article to back up my position even though I do agree with the conclusion reached that there is nothing wrong with 2.5 way woofers sharing the same volume.
Yeah, assuming. So why bother doing a test that just assumes what the outcome will be ? Not very scientific.
I would say that if the point of the exercise was to find out whether partitioning a 2.5 way was necessary or not, and what the differences might be, that actually testing a partitioned cabinet vs an un-partitioned one might be necessary. Silly me.
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