Why not horns?

Thanks Ralph, that makes sense but I wonder how it affects the sound? I have the high impedance drivers so the mid and tweet in parallel won't go below about 8-9 ohms at the high end assuming a resistive load. So it seems to me all my amp has to be able to do is maintain the output voltage into 8 ohms. That seems easy enough.

Getting ready to spin my copy of the Dukes of Dixieland "Barn Burner" since I now know it is the only thing that sounds good on my system.

Glad I don't have planar speakers. I guess the only thing that sounds good on them are flat instruments like the washboard and the gong.

.

.............................. bookmark

"too large footprint" is relative. I have plenty of room.

"poor bass" is just plain wrong. I bet you a donut I'm getting better bass from my horns than you are from those tiny Thiels.

.

"severely delayed"

How so? Of course I have made many compromises but that's not one of them. My mid-tweets are delayed so I am time aligned.

I've heard many Thiels and countless other box speakers. The bass is not as good and you can't dispute that unless you have heard the alternative.. I bet there aren't a handful of people here who have actually heard a front loaded bass horn of sufficient length and size like mine to properly produce a bass note.. Raise your hands....I'm not talking about rear loaded horns like the folded horns that most Lowthers are mounted in.. Sorry, there is a difference.

Of course there are those who are convinced every bass note will sound like it is coming from a sousaphone. I find that very amusing.

.

You are correct sir !!

However, if you dismiss all horns because you believe they have similar qualities that make them all sound bad then you must believe all box speakers produce sound with similar qualities. Not the that they all sound the same, but a driver in a box is a driver in a box and there is only so much you can do to mitigate that.

HONK !!!

HONK !!!

.

A Thiel is time coherent, which makes it unique in this regard.

Prez, what Thiel calls Time Coherence is time alignment, it is certainly not unique to Thiel. Google "time coherent speakers" and you will find many who make that claim including NSM, Green Mountain, Vandersteen, Meadowlark, and others including mine. I do not care to debate you on this, you are as wrong about this as you were about the last issue.

My physical crossover consists of a single capacitor in line with the tweeter. It is physically aligned with the mids and electronically aligned with the woofer through an electronic delay. All other crossover functions are done digitally with no phase shifts or timing issues. The next step is to get rid of that single cap and triamp completely eliminating any passive components between my amps and drivers.

You can question my methods but my speakers are most definitely time coherent.

.

Prez, you just said "I never said that Thiel was the only time coherent speaker out there"

but in an earlier post you said "A Thiel is time coherent, which makes it unique in this regard."

How can it be unique to Thiel if others do it?

And time alignment is not the same as time coherent.

OK, I read Thiel's description of time coherence, it looks the same as every description of time alignment I've read. I'm willing to be educated. What is the difference?

I have Duo Omegas on top. It is a first order crossover on the tweeter, a single cap in series with the driver.. The mid horn has no passive components. Details on their web site.

My woofer has no passive crossover, it is hooked directly to it's amp just like the mid horn is to it's amp. They are no order, no crossover.

Digital EQ/crossover can be non phase shifting

.

Prez, I hear what you are saying but I think the manufacturers are using terminology to confuse the layman in an attempt to carve out a unique slot in the marketplace. In other words, marketing BS. A change in arrival time is a change in phase no matter how it is done. They are synonymous. If you read Thiels papers they admit as much.

Either the different frequencies arrive at the ear with the same timing relationship they had when they were put on the recording or they do not. If not it could be that the drivers aren't aligned, That a digital or electronic delay was employed, or there is a phase shift through some reactive device like a crossover.

If they want to distinguish phase shifts caused by crossovers as phase coherency since they are frequency dependent and those caused by driver alignment as time coherency since they are not frequency dependent I'm on board with that, but time alignment and time coherency are the same thing.

By eliminating all reactive components after my amps (no crossover what so ever) and implementing the crossovers digitally before the amps I should only have phase shifts caused by the reactance in the drivers and hopefully the bulk of that is outside the band of frequencies they will be fed.. Each band can also be digitally shifted in time so they should be close to being time and phase coherent to use Thiel's terminology. The purists cringe when you talk about digital processing but so far so good.

One point of clarification, Even first order filters cause phase shift as you approach the cutoff frequency. Thiel claims that they have achieved equal but opposite shifts from the drivers above and below the cutoff so they cancel.

The phase shift is kept low by using very gradual (6 dB/octave) roll-off slopes which produce a phase lag of 45° for the low frequency driver and a phase lead of 45° for the high frequency driver at the crossover point. Because the phase shift of each driver is much less than 90° and is equal and opposite, their outputs combine to produce a system output with no phase shift and perfect transient response.

I'm still trying to wrap my head around that one. If one driver produces a sound shifted in time so it occurs slightly earlier than those in the passband and another produces the same sound slightly later how can that add up to no time change?

.

The difference is that some frequencies started before others. The delayed ones are a full cycle behind. They are still phase coherent but not time coherent.

It's not that simple. What you describe can only apply to steady state sine waves. Music is a complex wave with many frequencies starting and stopping and varying in amplitude. Different frequencies get shifted different amounts as they get rolled off so they don't line up like the original. They are not phase coherent.

I still say time alignment = time coherent. I've seen no evidence to the contrary.

.

Macro, you seem to be all shot in the butt with "experts." Why should I believe Bill Woods web site any more than I believe other horn maker's web sites. He says his way is best. DUH! What would you expect him to say. If you visit other horn maker's sites they will say their way is best. Go to a planar web site and find out why that approach is the best. Go to a box maker's site and find out why that approach is the best. You aren't going to convince anybody by posting over and over that if we would just visit his site we would find the truth about the holy grail.

Bill Woods web site is nothing more than a big advertisement for his products which is as it should be. That's not a bad thing but accepting his hyperbole as fact just because he is an "expert" and tells us how wonderful his products are is rather silly.

.

Wes, I would if I could. The physics of why is beyond me. I just know I like how mine sound. If you go to the AG web site they have a technical paper on why they are the best but what else would they say?

As for conicals; the reason I get from proponents of other designs for not using them is they require some EQ which reduces the overall efficiency of the speaker. Curious that Mr. Woods doesn't mention this on his web site, or perhaps I missed it.

,

Mapman, without saying anything bad about the Heresey, getting a pair to get a taste of what horns are all about will leave you with a very wrong impression of what horns like Macro's, JohnK's, and other cutting edge designs are currently capable of. There is simply no comparison so don't draw any conclusions about horns from the Heresey.

.

http://www.jeffreywjackson.com/

Go Orange