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Horns - Necessary to complete the Audiophile Journey?

Tom C

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I’m a little surprised and disappointed there hasn’t been more discussion of the Altec A7, since it’s my understanding these were used to mix many well known and popular recordings in days of yore. IIRC, Phil Spector used one in the construction of the studio’s (Capitol Records was it?) echo chamber. I saw a genuine vintage pair off to the side when I toured RCA’s Studio B last summer. It was a real treat to stand on the very spot on the floor where Elvis stood to make many of his most successful recordings, and to walk in the steps of giants like Chet Atkins, Charlie Pride, etc..
Since they were used in the studio, listening through a pair should solve some circle of confusion problems, right? I think you can get Great Plains Audio drivers (as close to the real thing as is possible to buy new today) in a well built exact replica cabinet from Gary Fisher for about $3,000. He has the genuine article, too, for a bit more $$.
 

mhardy6647

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I’m a little surprised and disappointed there hasn’t been more discussion of the Altec A7, since it’s my understanding these were used to mix many well known and popular recordings in days of yore. IIRC, Phil Spector used one in the construction of the studio’s (Capitol Records was it?) echo chamber. I saw a genuine vintage pair off to the side when I toured RCA’s Studio B last summer. It was a real treat to stand on the very spot on the floor where Elvis stood to make many of his most successful recordings, and to walk in the steps of giants like Chet Atkins, Charlie Pride, etc..
Since they were used in the studio, listening through a pair should solve some circle of confusion problems, right? I think you can get Great Plains Audio drivers (as close to the real thing as is possible to buy new today) in a well built exact replica cabinet from Gary Fisher for about $3,000. He has the genuine article, too, for a bit more $$.
More Duplexes (mostly 604s, but some 605s, too) than A7s used in studios in the golden age. A7s were really for sound reinforcement (more to the point, for movie theaters) and were hardly the sine qua non of the Voice of the Theater models.
The 811B horns typically found paired with the A7 bins was (is) -- umm -- not great. The 511B horns sometimes found on A7s (and bigger VOT models) are -- even more not great. The Altec multicell horns were far, far better sounding (as perusal of current prices will readily illustrate).
1595728974521.png

The Beatles (and Sir George Martin) heard themselves on Altec 605 Duplexes (in 612 cabinets) in the control room at Abbey Road.

beatlesinstudio 2
by Mark Hardy, on Flickr

And the Beatles do sound good on Duplexes -- I can vouch for that :)

RCA used -- RCA LC-1As :) in their studios. Phenomenal coaxes.
Elvis does sound good on LC-1As. :)

1595728863459.png

http://www.scottymoore.net/RCASpkr.html
 

Duke

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Listening window is defined as "average frequency response within a ±30º horizontal, ±10º vertical window."
Thanks, I had mis-remembered it as "30 degrees inclusive".

The JBL Array 1400 has relatively flat sound power above 1 kHz, similar to the Harman on-axis measurement.
Yes, I saw that in the graphs you posted here. That information is very encouraging to me.

Toole discusses the bipolar Mirage M1 speakers, which appear to be nearly flat from 200-10 kHz. I think it's important to note that Toole wrote that "[the M1" performed well in double-blind listening tests in the small NRCC room, and also in this large one" (referring to his own personal room at the time, for which he bought a pair).
Toole apparently really liked the bipolar M1s: "Over the years, a parade of loudspeakers went through that room, and all disappointed... Then in 1989, a new loudspeaker came on the scene: the almost omnidirectional, bidirectional-in-phase “bipolar” Mirage M1. They performed well in double-blind listening tests in the small NRCC room, and also in this large one. They simply “became” the orchestra.”

That last sentence is so enthusiastic it almost sounds like something an audiophile fanboy might write! And it's one of the reasons I think there might be some mileage left in polydirectional configurations; I think it's unlikely the genre reached it apex thirty years ago with the M1.

Probably helpful to distinguish between ipsilateral and contralateral sidewall interactions.
Good point. I was referring to the first ipsilateral reflections. Imo those are the only lateral reflections likely to arrive too early. Imo contralateral reflections are likely to be psychoacoustically beneficial, as they arrive at the opposite ear and thus contribute to decorrelation in the reverberant field with respect to the initial arrival.

If you're referring to the Harman single-speaker audition tests, I don't know that the relative strength of these reflections is likely to be meaningful. See my post above about Revel Salon 2 versus JBL Array 1400 listening tests.
In the single-speaker audition tests, the sidewall reflections are probably above the target threshold in time and/or below the target threshold in intensity. But my impression is that reflections which are "not an issue" based on these thresholds are still audible and still making a significant perceptual contribution... in other words, the room is far from anechoic. Or did I misunderstand you?

I think that it will probably be helpful to eventually make some distinctions, even if broad, about preferences, like Toole does regarding lateral reflections or perhaps like Tapio Lokki does for classical music: https://users.aalto.fi/~ktlokki/Publs/JASMAN_vol_140_iss_1_551_1.pdf.
Good point! My understanding is that early lateral reflections can have beneficial as well as detrimental characteristics. Image broadening is generally perceived as beneficial.

Thank you for the link to Tapio Lokki's paper. I have heard David Griesinger refer to him often, so it's about time I read his work for myself.
 
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tuga

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According to Toole, the Revel Salon 2 and JBL Array 1400 tested extremely similarly in Harman's listening tests, despite very different directivity:
https://www.audiosciencereview.com/...review-measurements.14310/page-17#post-442549
And despite a rather different (on-axis and listening window) tonal balance.
I'm afraid I don't think Harman listening tests are very effective or accurate; I question the methodology, the music selection and the use of non-trained listeners...
 

tuga

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Since they were used in the studio, listening through a pair should solve some circle of confusion problems, right?
Only on recordings monitored/mixed/produced with those speakers. But the inherent shortcomings may prove too taxing anyway.

If you are that meticulous then it might be wiser to used higher performance modern speakers and together with an EQ curve that mimics the A7's tonal balance.
 
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Yes, I saw that in the graphs you posted here. That information is very encouraging to me.
Great, I was responding to "My understanding is that Harman finds listeners prefer an approximately flat listening window response and then a smooth but downward-sloping off-axis response, and from that conclude this to be the ideal."

That last sentence is so enthusiastic it almost sounds like something an audiophile fanboy might write! And it's one of the reasons I think there might be some mileage left in polydirectional configurations; I think it's unlikely the genre reached it apex thirty years ago with the M1.
I agree, but I think it's a matter of both individual preference and selection of musical content.

In the single-speaker audition tests, the sidewall reflections are probably above the target threshold in time and/or below the target threshold in intensity. But my impression is that reflections which are "not an issue" based on these thresholds are still audible and still making a significant perceptual contribution... in other words, the room is far from anechoic. Or did I misunderstand you?
No, not anechoic, but first-order lateral reflections were >15 msec. I find it difficult to look at the description of preference testing like this and make any generalization about wider directivity or downward-sloping off-axis response being preferred or "more pleasing" in this setting. I suspect that the bass extension of the Array 1400 may have compensated for the less even on-axis and listening window response.

Good point! My understanding is that early lateral reflections can have beneficial as well as detrimental characteristics. Image broadening is generally perceived as beneficial. Thank you for the link to Tapio Lokki's paper. I have heard David Griesinger refer to him often, so it's about time I read his work for myself.
I thought it was interesting that this study suggested "that listeners can be categorized into two different preference classes. Some listeners prefer clarity over reverberance and the others love strong, reverberant and wide sound," also that they assessed three classes of attributes grouped into "reverberance, loudness and width;" "timbre"; "definition and clarity" but that "the individually collected attributes were also different depending on the choice of music." My feeling is that when it comes to speakers, probably there is a third, much smaller listener preference class related to timbre, for which the tonality of the speaker and its ability to reproduce the "correct" sound of an orchestra and specific instruments like violin or piano is paramount (REG comes to my mind here), hence issues like floor dip may become extremely undesirable and off-axis BBC dip might seem to compensate for microphone proximity.

Here is Lokki's list of publications: https://users.aalto.fi/~ktlokki/publications.html

Anyway, I don't think I have much else to say.

Young-Ho
 

Frank Dernie

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My feeling is that when it comes to speakers, probably there is a third, much smaller listener preference class related to timbre, for which the tonality of the speaker and its ability to reproduce the "correct" sound of an orchestra and specific instruments like violin or piano is paramount
That’s me, I think.
 

Purité Audio

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The speakers can only accurately reproduce the particular recording of that instrument.
Keith
 

Duke

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No, not anechoic, but first-order lateral reflections were >15 msec. I find it difficult to look at the description of preference testing like this and make any generalization about wider directivity or downward-sloping off-axis response being preferred or "more pleasing" in this setting. I suspect that the bass extension of the Array 1400 may have compensated for the less even on-axis and listening window response.
I was coming up with about 12 milliseconds for the first sidewall reflections (single speaker in the middle of a 21 foot wide room, ten feet listening distance), which is imo enough time delay to make it benign (assuming it's spectrally correct). It might still impart some image widening, since spatial attributes are discernible in Harman's single-speaker tests. But it's very encouraging to me that the narrow-horizontal-pattern Array 1400 is a solid contender.

I presume that the Array 1400's pattern is wider in the vertical than in the horizontal based on eyeballing the horn. Some researchers find that early reflections in the vertical are more benign than early reflections in the horizontal because they arrive at both ears simultaneously, and then (if not absorbed) that wide vertical energy comes back as beneficial later-arriving reflections. So I speculate that the unorthodox configuration of the Array 1400 might minimize early sidewall reflections while still sneaking a fair amount of energy in the later reflections.

In other words, the Array 1400's unorthodox configuration MIGHT actually be an improvement over a more conventional configuration which pattern-matches in the horizontal plane. Up until now the Array 1400 has looked ridiculous to me, but now I'm seeing it through a different lense.

I thought it was interesting that this study suggested "that listeners can be categorized into two different preference classes. Some listeners prefer clarity over reverberance and the others love strong, reverberant and wide sound," also that they assessed three classes of attributes grouped into "reverberance, loudness and width;" "timbre"; "definition and clarity" but that "the individually collected attributes were also different depending on the choice of music."
One of the things which can be adjusted with the system I'm doing is the direct-to-reverberant sound ratio. There is a threshold below which the additional reverberant energy does not degrade clarity, and for the "clarity" group, that would be the "sweet spot". The "reverberance" group may prefer to cross that threshold and trade off some clarity for more envelopment.

My feeling is that when it comes to speakers, probably there is a third, much smaller listener preference class related to timbre, for which the tonality of the speaker and its ability to reproduce the "correct" sound of an orchestra and specific instruments like violin or piano is paramount (REG comes to my mind here), hence issues like floor dip may become extremely undesirable and off-axis BBC dip might seem to compensate for microphone proximity.
I'm guessing that Tapio Lokki (what a cool name!!) did not include "timbre" as a third preference category because it is assumed to be correct since the source in a concert hall is live, unamplified instruments. On the other hand in home audio, timbre depends heavily on the quality of the source, which in this context is the loudspeaker system (ignoring for now Toole's "circle of confusion"). My foray into polydirectional speakers started out as a pursuit of more natural timbre, and it was only later that I became aware of possible spatial benefits. But too much of a good thing ceases to be a good thing if clarity is a top priority.

So I'm doomed to never build a "best" speaker, as it seems I'm always juggling tradeoffs. Maybe what I really need is a better marketing department.
 
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Duke

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The speakers can only accurately reproduce the particular recording of that instrument.
Keith
Which speakers, which recording, which instrument? I must be missing some context.
 

mhardy6647

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Frank Dernie

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The speakers can only accurately reproduce the particular recording of that instrument.
Keith
Very true Keith but I have been surprised how many speakers fall down on timbre in a way that doesn't seem to bother a lot of people.
My first demo of a high end surround sound system was so awful on music it put me off for years. It was fully THX M&K system and it sounded nothing like muical instruments at all.
The same dealer had a Steinway-Lyngdorf Model D system set up and it was super, in a completely different league. The difference in price was small, the difference on instrumental timbre vast.
 

Tom C

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Nope. No front horn loading on the woofer. It is a simple vented cabinet.
Read all about 'em (and you'll also see why they're now Frankenaltecs) -- they did start out to be what they were supposed to be. :)
http://www.wardsweb.org/Billfort/
Also see https://hifihaven.org/index.php?threads/billforts-altec-604-ramblings.47/

DSC_5735
by Mark Hardy, on Flickr

604E
by Mark Hardy, on Flickr
I had a chance to hear Troy Audio Achilles speakers at RMSF 2018. They were outstanding, really beautiful sound. They cost $40,000 a pair and had duplex drivers from Great Plains Audio. Downstairs, Bill H. from GPA had a desk set up with a few of his drivers that you could see and handle but weren’t set up to hear. When he told me he sold the drivers for about $1,000 retail each, I wondered how those cabinets could possibly be worth $38,000. They were nice, but not that nice, to be worth many multiples of the main system component.
 
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I've never owned horn speakers (unless one counts JBL 305 waveguides) in my life.


...but I've never owned a pair of horn speakers of any type, either partially or fully horned.

I'm wondering:

Is it finally time?


But I'm curious about their vaunted dynamic capabilities and if their other flaws are other accepting for that quality.

Will my audiophile journey be incomplete if I don't try them for a while?
Is it time to try horn type speakers? Sure, but Audition, audition, audition. Just like you wouldn't judge every traditional speaker the same, hold off judging every horned system from just one or two examples.

What I enjoy about many 2 channel horn systems is the lack of distortion, effortless micro/macro dynamics and the tone. Throughout the years I put on an unbelievable amount of miles in search of listening to new audio gear. Once I was exposed to decent horn systems I knew where my preferences were focused. My brother initially had a pair of DIY Altec speakers, now he's got Titans. I've got DIY Edgarhorn based speakers. The differences between our DIY speakers would be that my speakers gave you the impression of being at a live venue sitting at the soundboard, while his gave the impression of that same live event sitting in the first three rows. I would say take your time and listen to as many different systems as you can. Enjoy the ride!

hifiedgardiy.jpg
hifititan.jpg
hifi altec.jpg
 

MakeMineVinyl

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I’m a little surprised and disappointed there hasn’t been more discussion of the Altec A7, since it’s my understanding these were used to mix many well known and popular recordings in days of yore. IIRC, Phil Spector used one in the construction of the studio’s (Capitol Records was it?) echo chamber. I saw a genuine vintage pair off to the side when I toured RCA’s Studio B last summer. It was a real treat to stand on the very spot on the floor where Elvis stood to make many of his most successful recordings, and to walk in the steps of giants like Chet Atkins, Charlie Pride, etc..
Since they were used in the studio, listening through a pair should solve some circle of confusion problems, right? I think you can get Great Plains Audio drivers (as close to the real thing as is possible to buy new today) in a well built exact replica cabinet from Gary Fisher for about $3,000. He has the genuine article, too, for a bit more $$.
I use Altec A7-500s as my main speakers. They can sound outstanding because they have qualities which no other speakers made today have. BUT, it takes a hell of a lot of work to modify them to dampen resonances of both the HF and LF horns, along with active crossovers, voicing, and preferably tube amplification. Also, they need a large room (mine is 6000 cubic feet). The LF cabinets do not have any real bass extension below about 60Hz. You'll need to use subwoofers for that. A 60Hz lower frequency limit was standard in motion picture exhibition during this era.

The A-7 speakers were rarely used as monitoring speakers in the control room. In the control room they usually used the 604 duplex speakers. What they were used for was out in the actual studio to play back the master tapes so the musicians could hear the recordings.

By the way, contrary to folk lore, these speakers were NEVER intended for PA use. They were for use as their name suggests for motion picture theaters. The primary reason these speakers have gotten a bad rap is precisely because they were used in PA systems when they had no business being placed into that role.
 
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tuga

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When he told me he sold the drivers for about $1,000 retail each, I wondered how those cabinets could possibly be worth $38,000.
Intelectual property and a market.
 

Tom C

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I use Altec A7-500s as my main speakers. They can sound outstanding because they have qualities which no other speakers made today have. BUT, it takes a hell of a lot of work to modify them to dampen resonances of both the HF and LF horns, along with active crossovers, voicing, and preferably tube amplification. Also, they need a large room (mine is 6000 cubic feet). The LF cabinets do not have any real bass extension below about 60Hz. You'll need to use subwoofers for that. A 60Hz lower frequency limit was standard in motion picture exhibition during this era.

The A-7 speakers were rarely used as monitoring speakers in the control room. In the control room they usually used the 604 duplex speakers. What they were used for was out in the actual studio to play back the master tapes so the musicians could hear the recordings.

By the way, contrary to folk lore, these speakers were NEVER intended for PA use. They were for use as their name suggests for motion picture theaters. The primary reason these speakers have gotten a bad rap is precisely because they were used in PA systems when they had no business being placed into that role.
Thank you. That makes sense.
 

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