horn loudspeakers, are there any disadvantages?

Yes, it did. Thanks!

If you or anybody else has the time for another horn question: any idea why some horns are mounted in a vertical orientation, like those on JBL's Project Array series (man I look like a schill in this thread don't I )? I would think this would limit horizontal dispersion.......or maybe that is what the designer wanted?

 

I can't say from actual experience with the Array series because I haven't heard them. I have read some opinions about them and the lack of horizontal dispersion was common to all of them. There seems to be a definate sweet spot, luckily, that's where I sit anyways . I use JBL 2397 Smithhorns and they are touchy vertically, absolutely DREAMY horizontally.

 

I have been under the impression that all models in the Klipsch Heritage line have reasonably deep bass?

 

Well, it's according to your definition of "reasonably deep bass" .

I believe the LaScala to be a bit bass shy with some recordings and excellent with others. I've heard some say the LaScala delivers all the bass that is fit to hear. I would prefer it to go a little deeper but my listening space just does not allow it. Cornwalls and Khorns go down the deepest. But in a particular space or system, Heresy's may be all you need.

It's all in the ears of the beholder, their equipment, and their room.

Here are some specs on each.

Heresy
Cornwall
Belle
LaScala
Klipschorn

 

'.....all the bass that's fit to hear.' That comment is very true. Too often the recordings that I listen to most, nowdays seem to have nothing good down below my 8" driver's capabilities. Listening to a lot of pre-'70s jazz I don't miss deep performance, at all.

I've never owned La Scallas, but I've auditioned them in-store every chance I get and I don't hear any lack of bass. A slight lack of sub-bass would annoy some people who enjoy pipe organ music or special effects bass, but not a problem with most music.

 

I like the dynamic capability of horns but I find them lacking in resolution and the amount of air around the instruments. I like some of the Klipsch products but the Avantgarde Audio I have never heard sound good despite many shows and listening sessions.

I find planars to offer more presence and overall midrange purity.

 

Somewhat agree on the Avantgardes. But Acapella are pretty special - I thought the Acapella Violon High Sub was extremely good at both the points you noted. They seemed to have excellent resolution and air around instruments. One of the nicest speakers I've ever heard.

 

JBL

It is tough to find a horn system that has everything going for it. Most current models are usually priced out of the reach of most people's budget too. Just like any other type of speaker, the design and quality are what makes or breaks them. I've been suprized to open up some speakers, only to find some puny little 'thing' they call a compression driver. I've done a lot of searching over the years and found a great combo, that while not cheap, a second mortgage is not needed either. Great dynamics, airey presence, very high resolution and project a wide soundstage. It is the JBL 2397 Smithhorn with JBL 2441 2" exit, large format compression driver. The 2441 uses a 4" aluminum diaphragm with a 4" edgewound voicecoil. It is a massive driver that weighs between 25-30lbs. I use a vintage VTL EL34 based Model Stereo 45 amplifier to drive them and cross them over electronically. I wish that these were a current, easy to find, item. I believe they would change some opinions about horns. If you ever get a chance to audition some, take it. It's all about the music with me, I am past the point where it becomes an argument between speaker types. Just for the record, my feeling is: whatever suits you and makes you happy, enjoy it.

 

Many of the custom JBL monitors in studios that I saw, by both Westlake and George Augspurger used the 2397 Smith horns with 2440 drivers. Usually they were mated with dual 15" woofers (JBL 2220's or 2230's IIRC) and a 2405 spitter or two. What is not so clear from your photo is that the horns are made of wood.

If you can believe it, we had 4 of those monsters at Dawnbreaker. We never did anything in quad though the Helios did have a few quad panners installed. Instead they would be used to demo mixes at 130db levels. How anybody could hear anything intelligible that way is beyond my understanding. We would often have listening parties in the main studio when an album was done, and I'd usually put some 4320's in there with a decent amp. That usually sounded much better than the control room to me.

Btw, we drove the custom monitors with GAS Ampzilla amplifiers. Those suckers sounded great but were a nightmare to keep running due to excessive heat. Fortunately GAS was not far from the studio. I can't remember if they were bi-amped or tri-amped. I did get to work with Jim Bongiorno quite often as a result, who was responsible for designing many classic amps.

 

Yes they are original wood 2397's. They were in sad cosmetic shape so I painted them.

 

2405 spitter

JBL ring radiators sound and perform much better if they are electronically crossed over and driven by a small, high quality amp. I just learned this and tried it. It is true, they sound quite good to my ears

 

Very Cool!!!. I had an SAE P250 for a while, I believe James was responsible for it's design too. My system is tri-amped. I use a Yamaha MX-1000u on the bottom, VTL tube for the mid and a Yamaha M-35 on top. Great sound.

 

When I started doing pro sound we built some of the best floor monitors I've ever heard. They had (2) 12" 2130's, a 2470 2" compression driver on a 2305 'potato masher' horn, and a 2405. The trick to this monitor though was the amplification. We used Spectra Sonics amplifier cards. Each woofer got a bridged pair (120 watts). The horn also got a bridged pair, and the 2405 got a single 60 watt amplifier card.

For those of you not farmiliar with Spectra Sonics, they had a modular amplifier card system and a 3 1/2" rack that could take 8 cards plus a 2 or 3 way crossover. It had a mother board which allowed any configuration to be selected by soldering in jumpers. So one full rack could power each monitor. These things were so loud and had so much headroom that I could just about blow people's heads off. In fact many acts I mixed loved them so much that they offered me positions touring with them. Of course, I gave most of the credit to the monitors, but the knobs did have to be turned right to make them work their best. I was very fortunate to have such kick *** monitors to work with.

 

Yes I think he was. He also designed for Marantz, and Dynaco after David Hafler left. From there he went to SAE and then GAS. I belive he also designed some Sumo Class A stuff.

 

OMG!!, I've hadn't heard anyone ever mention Spectra Sonics, at least not in the last 25 years. Yes, I am aware of those wonderful SS amps. My first real experience was listening to 4 JBL 4311's powered by a Spectra Sonics amp. Super clean, robust amps. Wow, you really brought back some good memories there

 

Do you know Jack Sproul aka JackmanWolf?

 

I actually used a Spectra rack for my home stereo around this time. Of course I could never let anything be. I was constantly trying to mod the amp to make it sound better. I found two problems with them that I was able to improve on, much to the chagrin of Mr Dilly, the original designer from Ogden Utah. They had a choke in the output to insure stability which when bypassed made the amp sound much better and go much higher in response. Of course it was more likely to pick up any stray rf without the choke. Also the method that they bridged the amps was to take a feed off the first amp and send it to the inverting input of the second. This method was safe but had a slight propogational lag. I used an external phase splitter to drive each card separately.

These amps were really quite practical. Their biggest problem was in their power supplies. In complex installations one could tie all the power supplies feeding many racks in parallel for redundancy. That way if one went down (and it would) all of the amps kept working.
Another problem was that the amplifier output devices would loosen up from the awkward heat sink arrangement and that could lead to failure. Folks would often grab the sinks to pull cards out and that was usually the reason for the loosening.

Btw, Spectra Sonics also made wonderful sounding consoles. The were all modular using various cards for mic pres, line amps, summing amps, compressors, etc. IIRC Mama Jo's Studio had one and Ambrosia cut much of 'Somewhere I've Never Traveled' on it. We had a live console full of SS 101 mic amps. At first our rep in LA was Al Siniscal, but soon after that Ray Kimber took over. Of course this was long before he started playing with cables.

Oh well, back to the horn thread. Sorry for the partial derailment.

 

This is from the JBL 4320 data sheet.

The compression driver is coupled to a heavy cast aluminum exponential horn and slant-plate acoustic lens. The lens is designed according to advanced sound wave propagation theory and acts exactly as a divergent optical lens. Basic parameters of the device were derived using the formula for hyperbolic cylindrical lens. It employs 11 plates set at an angle of 30 degrees spaced 0.25 inches center to center. The precisely calculated hyperbolic curvature of the projecting surface spreads sound evenly through a 120 degree lateral angle, restricting dispersion to approximately 40 degrees in the vertical plane.

Btw, I still have all the original data sheets for most of the JBL products of the 70's if anybody has any interest or questions. I haven't been able to find them on the web.

 

I found more on the lenses from the JBL Professional Series Acoustic Lens Family data sheet.

The JBL family of acoustical lenses was originally designed for stereophonic audio systems for motion picture theater applications. They were first presented to the industry in 1954. The acoustic lens, which had been described by Bell Laboratory scientist Kock and Harvey in 1949, had not previously been applied to commercial sound reproduction. The acoustic lens, as engineered by JBL, was the first real innovation in high frequency sound reproduction since the early 1930's.

Within certain limits, the acoustical lens can be made to function as an optical lens to achieve any desired high frequency distribution pattern. In JBL lens systems, the lens is attached to a short horn device so that the wavefront approaching the lens is a properly constituted plane wave.

The 'slant-plate' acoustical lenses utilize a series of plates with carefully calculated hyperbolic shapes which results in a horizontal response pattern that does not converge with increasing frequency. The plates are spaced to allow the lens diffraction effect to be maintained at high frequencies. The vertical response is determined by the horn shape behind the lens.

The 'perforated plate' lens assembly consists of a collection of perforated barriers at the horn mouth. These perforated screens are actually ring shaped with varying sizes of center cut-outs. Thus, the profile of the assembled plate openings describes a hyperbolic shape in all planes resulting in a conical pattern. The lens diffraction is determined by both plate spacing and the size of the holes of the screens.

The 'soft-edge- pattern of these acoustical lenses is well suited to high quality music reproductions systems and short-throw reinforcement applications.

 

And he was a snappy dresser as well!

 

So I'm assuming all those other lower priced speakers back then that used these types of lenses mounted directly on top of a cone tweeter was just something their marketing department thought would make them look more "hi-tech"?

 

I'm not sure which brand or model you're talking about. There are some benefits to to the practice and I'm sure some are gimmics.