Do I need a three way?

[R-Carpenter]

TYVM for your thoughts. I believe I understand the gist of what you are saying, and thanks for keeping it KISS, because I'm sure it otherwise would get very long and technical, very quickly.

As I pretty much know nothing about speaker design, at least compared to an expert like you, I do not even know what you exactly mean when Don's drivers are "only 90 degrees apart". In phase if I had to guess, but, I wouldn't think any amount of degrees are good? I also do not know how small these angles can typically be in a speaker, nor how large. I, of course, do not have the slightest inkling on why certain angles provide better transient response than another.

Ok, looking at the graphs, you must mean the amplitude response?

It's fine with me if you don't explain, if it's the case that your time would be wasted on a neophyte. I'll let you discriminate where typing might benefit a neophyte.

I understand your thoughts about how I was thinking about this backwards. I suppose I meant that if one had free access to any specific drivers, if one would choose a certain set if only due to preference of xover slope necessitated. I'm sure that's still backwards, as drivers should be picked firstly based on their performance for the money. I was being hypothetical.

IIRC, persons that prefer steeper slopes might've pointed out off-axis response as the main reason.

Anyways, thanks.

I think one should choose the drivers based on their performance, coloration and budget. Look at the crossover as a tool to alter complex driver behavior.
I don't see a clear advantage between first order crossover over 4th order electrical as an absolute statement. Either crossover will work with some drivers and will be terrible with other. It all depends on what you trying to achieve in the end.
As far as 3 way VS 2.5, I would prefer 3 way speaker. True, it's significantly more complicated to design but we are not talking about designing a loudspeaker. The benefit of a steeper slope is the ability to use the driver with narrower low distortion bandwidth in a desired configuration.

 

[jostenmeat]

TLS, Thanks again for your very educational and interesting replies. More questions, naturally.

Now as you add orders, you are really cascading filters, so you add 90 degrees of shift per order.

Wouldn't this by itself imply a preference for 1st order, assuming one has free access to any drivers? (side question, for bonus points: if a sub is using a LPF of high order, does the phase adjustment on any unit essentially solve, say, a 360 degree shift from a 4th order pass?)

There have been attempts to set the tweeter back. However the awkward cabinetry causes reflections and on the whole does more harm than good.

For some reason, the first speakers I think of are Thiel. I've not heard then, only seen them. So that was the reasoning, eh? Is the slope backwards essentially causing (I'm pulling from thin air), some sort of unwanted direction of the drivers' diffraction?

The up shot is, that harmonics get physically separated from their fundamental in time and space.

Ok, here I am pretty lost. OK. I just looked up the definition of upshot, and for some reason I mistakenly thought it implied something positive. I had to look up the definition, since in your previous post, this is stated:

So where possible, I try and cause the least separation of harmonics from their fundamentals in my crossover design. If you choose the right source and are sensible with spl, good full range drivers like the Jordan Watts modules I have in my possession, are a revelation. I may be more sensitive to this time smear than average, as I listened only to those full range drivers, for a great many years, and still keep them as reference, for these sort of issues. I could not tolerate speakers with crossovers, until crossover design was better understood. I was a very early adopter of computer aided design.

OK, making more sense. Separating harmonics from the fundamental can't be a good thing, though I'm sure the effect may only be subtle at times. I would also presume this matters much more for acoustical intstrumentation and vocals, where harmonics define the color of any instrument for us, those of which we do happen to be familiar with in real life.

When Peter Walker launched his Quad electrostatic loudspeaker at the Audio Fair at the Hotel Russel in 1957, other manufacturers were shaken.

The management of Goodmans loudspeakers charged Ted with coming up with a competitive product. He went to work on a full range loudspeaker.

That must've been a most exciting and interesting time for you.


EDIT: forgot to ask about full range drivers. Do I presume the main drawback to such a design to be compression at higher SPL? Perhaps another would be extremely high cost for a good one? For why else would we not use them more often? A xover-less design seems to be a holy grail of sorts, no? Zero phase issues.

 

[TLS Guy]

TLS, Thanks again for your very educational and interesting replies. More questions, naturally.

Wouldn't this by itself imply a preference for 1st order, assuming one has free access to any drivers? (side question, for bonus points: if a sub is using a LPF of high order, does the phase adjustment on any unit essentially solve, say, a 360 degree shift from a 4th order pass?)[/QUOTE]

On the face of it yes, as you can construct a transient perfect crossover, with excellent pulse response. These are the most difficult designs to bring off. One took me 10 years. The problem is that it is seldom practical and handling driver interference remains a limiting factor. For woofers, I think the phase control is only 180 degrees, i don't know because I don't own one. If so it would not correct 180 degrees. However subs are seldom aligned with the mains, so the issue is mute.



For some reason, the first speakers I think of are Thiel. I've not heard them, only seen them. So that was the reasoning, eh? Is the slope backwards essentially causing (I'm pulling from thin air), some sort of unwanted direction of the drivers' diffraction?[/QUOTE]

Thiel really believes in first order filters. Yes, the slope backwards is important. Odd order crossovers have 15 degrees of tilt to their lobing pattern, which with tweeter on top is downwards. The backward slope corrects for the 15 degree tilt, so the acoustic axis is towards the listener, and it corrects for the 1/4 wave length time advancement in the crossover.



Ok, here I am pretty lost. OK. I just looked up the definition of upshot, and for some reason I mistakenly thought it implied something positive. I had to look up the definition, since in your previous post, this is stated:[/QUOTE]

Sorry! English vernacular.



OK, making more sense. Separating harmonics from the fundamental can't be a good thing, though I'm sure the effect may only be subtle at times. I would also presume this matters much more for acoustical intstrumentation and vocals, where harmonics define the color of any instrument for us, those of which we do happen to be familiar with in real life.[/QUOTE]

Yes, when you see what is happening, it is truly astounding that loudspeakers are as good as they are.



That must've been a most exciting and interesting time for you.


EDIT: forgot to ask about full range drivers. Do I presume the main drawback to such a design to be compression at higher SPL? Perhaps another would be extremely high cost for a good one? For why else would we not use them more often? A xover-less design seems to be a holy grail of sorts, no? Zero phase issues.[/QUOTE]

The problem is that the cones have to be relatively small and light, which means the suspension has to be unique to get any bass response. The JW has a four inch tractrix aluminum cone and weighs 6 GM. The suspension is three beryllium cantilevers, two of which feed the signal to the voice coil. Power is 15 Watts. However a pair of those drivers do achieve an spl comparable to the Quad 57 ESL. So the problems are limited power handling and a relatively fragile driver. However the panels in the Quad 57 are easily blown also, in fact I think more easily. So I think Ted really did come up with a comparable product!

The driver had a good solid niche market in Europe and especially Asia, where it still enjoys cult status. North America was a different story, where owners regularly achieved cone voice coil separation, and or oil canning of the cones. Owners could, and did, turn the cones into "cocked hats".

I made a pair of small labyrinth speakers with with those modules when I was a teenager. Those speakers are still in use and have never been touched, and they sound very good.

 

[R-Carpenter]

Man I do dislike J drivers. I had 6 drivers in my possession and most of them needed to be repaired from the start (used drivers, not new). Dust cones were getting unglued from diaphragm.

Full range drivers as any other drivers have their own advantages and disadvantages. Zero phase shift is one of the advantages. Ragged Frequency response, limited dynamic range and low power are disadvantages. Due to the physical cone radiation properties, off axis response goes to hell and back (One for J drivers, way better then Fostex or Dayton in off axiss response region). Full range drivers can benefit from the crossovers as well as regular drivers. It all depends on the design and purpose of a loudspeaker. I have a commercial line of speaker to be lunched in a couple of month, based on the new Dayton Full range drivers and if you use them correctly within their limitations, it's great but as well as other drivers they will not do everything correctly.
Theil makes some great sounding loudspeakers. Great attention to details, especially in the crossover region. I am not sure if time-aliened loudspeakers have been proven to sound better or at list audibly different in independent test?

 

[TLS Guy]

Man I do dislike J drivers. I had 6 drivers in my possession and most of them needed to be repaired from the start (used drivers, not new). Dust cones were getting unglued from diaphragm.

Full range drivers as any other drivers have their own advantages and disadvantages. Zero phase shift is one of the advantages. Ragged Frequency response, limited dynamic range and low power are disadvantages. Due to the physical cone radiation properties, off axis response goes to hell and back (One for J drivers, way better then Fostex or Dayton in off axiss response region). Full range drivers can benefit from the crossovers as well as regular drivers. It all depends on the design and purpose of a loudspeaker. I have a commercial line of speaker to be lunched in a couple of month, based on the new Dayton Full range drivers and if you use them correctly within their limitations, it's great but as well as other drivers they will not do everything correctly.
Theil makes some great sounding loudspeakers. Great attention to details, especially in the crossover region. I am not sure if time-aliened loudspeakers have been proven to sound better or at list audibly different in independent test?

Did you have Jordan drivers, or the original Jordan Watts module. There is a big difference.

The Jordan Watts units are actually very smooth, with slight roll off above 6 kHz. They are not spiky at all. Other full range drivers I have had are.
Did your drivers look like this?

Ted Jordan left Jordan Watts after the failure of the MkI. I doubt there is a MK I in existence. The MK II was right from the start. The one shown in the brochure is a MK II, and the bulk of the production were MK IIs. The last years of production, prior to Jordan Watts being sold to Volt loudspeakers, were the MK III, in which I was involved. The MK IIIs had a rolled rubber surround. One strange think, I have never had a foam surround of a MK II rot out.

The Jordan Watts drivers were made at Benlow works. The enclosures were at the Hackney cabinet works. They were the coach builders for Rolls Royce, and made their wood work.

 

[R-Carpenter]

Did you have Jordan drivers, or the original Jordan Watts module. There is a big difference.

The Jordan Watts units are actually very smooth, with slight roll off above 6 kHz. They are not spiky at all. Other full range drivers I have had are.
Did your drivers look like this?

Ted Jordan left Jordan Watts after the failure of the MkI. I doubt there is a MK I in existence. The MK II was right from the start. The one shown in the brochure is a MK II, and the bulk of the production were MK IIs. The last years of production, prior to Jordan Watts being sold to Volt loudspeakers, were the MK III, in which I was involved. The MK IIIs had a rolled rubber surround. One strange think, I have never had a foam surround of a MK II rot out.

The Jordan Watts drivers were made at Benlow works. The enclosures were at the Hackney cabinet works. They were the coach builders for Rolls Royce, and made their wood work.

No. They looked like modern Jordan and Bandor drivers. I have the data on them somewhere on my work computer. As far as I remember one of them was XJ55? I don't doubt that they have their strong points in sound reproduction, but the price, long wait and inconsistency makes them somewhat difficult.
I wish I did CSD at the time. Somehow Jordan despite being spun aluminum are great on female vocals. And there's a driver for the first order crossover BTW.

 

[TLS Guy]

No. They looked like modern Jordan and Bandor drivers. I have the data on them somewhere on my work computer. As far as I remember one of them was XJ55? I don't doubt that they have their strong points in sound reproduction, but the price, long wait and inconsistency makes them somewhat difficult.
I wish I did CSD at the time. Somehow Jordan despite being spun aluminum are great on female vocals. And there's a driver for the first order crossover BTW.

Yes, your drivers were from E.J. Jordan designs. The Jordan Watts drivers are significantly different. They hold up much better, and sound better.

 

[jostenmeat]

I am not sure if time-aliened loudspeakers have been proven to sound better or at list audibly different in independent test?

I'm sure you meant aliGned, but it's somewhat hard for me to believe that this would not be discernable. I guess it also depends on the extremes of what we were to compare. I would in fact guess that being "time aligned" would be one of the most important characteristics there are in achieving.

 

[R-Carpenter]

I'm sure you meant aliGned, but it's somewhat hard for me to believe that this would not be discernable. I guess it also depends on the extremes of what we were to compare. I would in fact guess that being "time aligned" would be one of the most important characteristics there are in achieving.

Yes, thank you for the correction jostenmeat.
Why do you think that the fact that loudspeaker is 'time aligned' makes such a big audible difference?

Some good info here: http://www.musicanddesign.com/

If you have a link to independent blind test or any other research proving audible differences, I'd be very interested to look at it.
Thanks, Roman.

 

[jostenmeat]

Yes, thank you for the correction jostenmeat.
Why do you think that the fact that loudspeaker is 'time aligned' makes such a big audible difference?

Some good info here: http://www.musicanddesign.com/

If you have a link to independent blind test or any other research proving audible differences, I'd be very interested to look at it.
Thanks, Roman.

Thanks for the link. Roman, I'm talking out of my butt, an unfortunate habit that's hard to kick. Really, I'm just conjecturing. But, thanks, you made me think about it. There must be many ingredients to making something good I suppose. I guess, just to conjecture some more, freq response would be a big deal. I've thought to myself before that a xover was displeasing to me, because of what was happening between (or so I thought) the tweeter and mid of a certain speaker. Now that you've made me think some more, I can't say for sure that it's not something else entirely, perhaps something like very unmatched drivers in freq response, and may have nothing to do with phase (though I feel* that might've been what it was). My noobish guess at the time was that it didn't sound "phase coherent". Then... maybe it was the room acoustics! Or that the room somehow unfortunately exacerbated any funkiness within the xover design.

Oh, I don't know. For instance, a first reflection that occurs too quickly to a listener is supposed to create "smear" since we can't distinguish it from the direct audio. Say my head was two feet away from this reflection. I guess the phase difference even in a poorly designed speaker would not have this much "phase shift". Or, who knows.

I wish I knew more.

 

[annunaki]

In response to the thread title: who doesn't?

One doesn't need it per say, but it would be an experience.

 

[Alex2507]

One doesn't need it per say, but it would be an experience.

I'm so happy to see this thread get back on track.

 

[TLS Guy]

I'm so happy to see this thread get back on track.

I don't think it was ever off track. The crossover issue is front and center of the problem. The whole issue of the three way is the classic advantage/disadvantage issue. There are advantages to three ways, but they add a lot of baggage as well.

 

[Alex2507]

There are advantages to three ways, but they add a lot of baggage as well.

Especially if it's with a dude.

 

[lsiberian]

3-ways just complicate things, but they do make a lot more noise. Hence the -6db calibration for my only 3-way compared to my 2-ways I guess you could say i'm mostly a 2 way man. At least 6/7ths of the time.

 

[annunaki]

I don't think it was ever off track. The crossover issue is front and center of the problem. The whole issue of the three way is the classic advantage/disadvantage issue. There are advantages to three ways, but they add a lot of baggage as well.

Nice post by the Dr.! +1

 

[Nomo]

Especially if it's with a dude.

Bad Monkey.

 

[jostenmeat]

Especially if it's with a dude.

You are incorrigible.

 

[Alex2507]

incorrigible.

I never really knew what that meant until now.

When I was in the 5th grade during lunch, I figured out how to use my spoon as a catapult and shot this pea way to the other side of the cafeteria. It landed in the middle of the teachers' table causing them to accusingly look up at each other.

It was a complete fluke as they were 40'-50' away. The crazy part is that later during the same lunch one of the lunch room mothers storms up to me as I'm eating and hating the rest of my peas and says, "You got an innocent face but I know your type", turns around and marches off. There must have been 300 kids in that caf.

What kind of nut job says $h!t like that to a 10 year old?