[MartinV56]

Hi People, my second post


http://img542.imageshack.us/img542/1651/s4010297ed.jpg

My Horns

Bass: Back Load Horn
Mids: Edgar Tractrix Horn with JBL LE5-2
Hi: Bi-radial horn

Greatings and thanks

More Horns:

http://www.hifichile.cl/index.php?/topic/921-horns/page__pid__110447__st__480#entry110447

[JBLMVBC]

Horns are good! And dynamic...

[doug s.]

welcome, martin!  yes, horns are good!   

doug s.

[Gothover]

I love your Tractrix mid horns, very nice.

Dave

[Russell Dawkins]

Greatings and thanks

More Horns:

http://www.hifichile.cl/index.php?/topic/921-horns/page__pid__110447__st__480#entry110447

That is an amazing link. I have been going through this thread on HiFi Chile with fascination. It will take days to devour. Just the first link on the first post on the first page of this thread (the link sends you to page 17) alone will make your head spin!

Welcome to AudioCircle, MartinV56, and thank you!

Russell

[Rclark]

 Ok, Russel, Doug, perfect. You guys are here.

 Why do people bag on horns and why are they wrong? Discuss.

[Russell Dawkins]

Why do people bag on horns and why are they wrong? Discuss.

I think when horns systems are done cheaply and carelessly, they can sound really nasty. Direct radiator systems done cheaply and carelessly can also sound nasty, but they are typically quieter.

Nasty and loud sounds worse than nasty and quiet.

A compounding issue is that inferior - that is, most - amplifiers tend to really mess up "the first watt". I understand this is mainly due to the zero-crossing distortion of a class AB amplifier remaining constant as the output diminishes.

This doesn't matter so much when it is driving an insensitive direct radiator speaker, since it is running typically 0.1 - 10 watts. However, when the same amp is driving a 100dB/W/M horn speaker it may be operating between 0.005W and .5 watts for the same acoustic output (allowing for a sensitivity of 87dB/W for the direct radiator). Most class AB amps don't do well at those power levels, and perhaps for this reason you seldom see THD distortion specs for anything under 0.1 watt. For high sensitivity speakers what is going on between .0001 watt and 1 watt is all of interest.

This, incidentally, was specifically addressed by Bruno Putzys in discussing his Ncore design, and may be an important part of the formula contributing to the superior sound being reported. The distortion graph on his NC400 data sheet shows 10mW (0.01W) - at 0.015%.

[playntheblues]

Martin, thanks for the link.  I have always had a soft spot for horns and their dynamics.  A fellow member Ka, has his horns on that thread, very cool.

[Letitroll98]

A compounding issue is that inferior - that is, most - amplifiers tend to really mess up "the first watt". I understand this is mainly due to the zero-crossing distortion of a class AB amplifier remaining constant as the output diminishes.

This, incidentally, was specifically addressed by Bruno Putzys in discussing his Ncore design, and may be an important part of the formula contributing to the superior sound being reported. The distortion graph on his NC400 data sheet shows 10mW (0.01W) - at 0.015%.

Also discussed in some detail by Dr. Earl Geddes when giving reasons why he chose a cheap Pioneer receiver to drive his speakers at a big audio show.  Vanishingly low crossover distortion.  Also a reason why Class A amps are often preferred.

(Thanks to Anand for correcting a senior moment, inside joke)

[doug s.]

the reasons why folks like horns is because the realism of dynamics of highly efficient speakers is something to behold.  many true horns are wery efficient.  also, many horn designs use relatively full-range drivers, which leave x-overs outside critical frequencies.  my triamped horn system has x-overs at 80hz and 300hz.  and, w/the adwent of quality dsp, such as the deqx, some of the anomalies of full-range drivers, which are offensive to some folks, can be effectively tuned out...

doug s.

[JoshK]

I have some slightly different opinions on why horns are superior.  You can read "why horns?" by Dr. Edgar if you want it said better than I, but here is my take.

1) Horns are significantly lower distortion.  Now on the surface, that isn't 100% true, as compression drivers have somewhat measurable 2nd order distortion due to the non-linearity of the compression of air in front of the diaphragm.  However, that is more or less where the distortion ends and our ear is very insensitive to 2nd order distortion.
At moderate output, horn systems, ex the 2nd have an order of magnitude lower distortion.  This aids in realism, immediacy and electrostatic like qualities.  The diaphragms/cones are moving an order of magnitude less, so the non-linearities of the driver are almost moot.
Power compression:  for home use, there isn't any.  This is a stark contrast from the typical 6" two way box speaker. Anything more than a handful of watts just heats the voicecoil and creates compression, but with high efficiency speakers, that area is never met.
2)  Controlled directivity is FAR too often ignored by audiophiles, but is probably one of the most important aspects of reproduction.  There are two solutions to the problem, you either make the forward power response smooth and even or you go omni-direction, anything else is *suboptimal*.  Acoustic treatments can only provide a bandaid to a poorly designed problem.  Audiophiles seem to think the on-axis sound is the only thing that matters, but they are dead wrong.

The fact that horns are efficient and allow for simple low powered amps is almost a side benefit, but simple amps sound better than complex amps. 

The downside, and there are significant downsides, are they are big, especially if you do it right.  They are *really* hard to design correctly.  Virtually all commercial horn speakers have significant compromises to make them practical.  Nothing wrong with compromise, but it may not be the compromise *you* would wish to make, but its the one that makes it economical for the manufacturer.