Indeed!
Way back when I asked Altec how they QC'd their drivers and they only measured efficiency [n0] with a +/- 0.1% QC tolerance since it quickly 'covered all the bases', so individual specs can be pretty far off and still match up 'close enough' WRT speaker system design, replacing bad drivers, etc., and of the few driver designers I've polled over the years is still in use.
[n0] = [[9.7822 * 10^-10 * Vas * Fs^3] / Qes]
What none told me was how they measured it in a manufacturing plant's noisy environment and once shipped to my locale's distributor they only checked Fs, polarity the times I got to watch.
SPL @ 1W/1m = [112.2 + 10 * log [n0]]
GM
Depends on the compression driver's design, i.e. all the vintage ones I've experience with are reactance annulled, so has the same response regardless of whether it's sealed or not except for all the dipole comb filtering notches in its response.
Known only one pro 'hornie' experimenting with it and ultimately added a second identical horn behind it to create a very HE dipole.
If DIYed using a cone driver, then its tuning will drop to Fs or lower depending on amount of horn loading with a dipole's power handling below horn Fc, i.e. fractional in comparison IME.
GM
Known only one pro 'hornie' experimenting with it and ultimately added a second identical horn behind it to create a very HE dipole.
If DIYed using a cone driver, then its tuning will drop to Fs or lower depending on amount of horn loading with a dipole's power handling below horn Fc, i.e. fractional in comparison IME.
GM
By playing around, I've found around 2kHz is a good range to start widening the highs with my speakers and in my room. But that's a sample size of one, there hasn't exactly been research on this that I know of.
I wouldn't get too concerned about having what radiates the highs to the outsides being phase coherent with the direct wave since you're going to be hearing them reflected from multiple places anyway. Being from different drivers or driver types shouldn't be a big deal. It does seem that having the stuff radiated to the back and walls be delayed works better, but even without the delay it seems to be pretty good (the reflection distances also add delay). The problem there without delay would be avoiding spoiling the direct signal with coherent interference. Like it would be nice to have the ambience drivers radiate everywhere BUT toward the listening position!
sounds like you need the tweeter pods of a classic disco system. They are controlled as an additional DJ effect where the main mix is high passed and then the DJ can control the level of the pods as an addition to the sound coming from the main stacks. Notice in the traditional design the tweeters are not pointed directly at the dance floor but are instead above the heads of the dancers firing at the walls.
While this discussion is on pros & cons of speakers directivity, my take is finding the correct speaker that works in our listening space first. A case in point my room, my ML Odyssey sound wonderful with wall to wall sound etc, one day out of curiosity I hook up
a Duevel Planets just for a listen, no matter where I move the speakers I will always be looking down as sound is not being projected above which is strange as it's an Omni.
My room is 6 X 7 metres side walls far far away.
a Duevel Planets just for a listen, no matter where I move the speakers I will always be looking down as sound is not being projected above which is strange as it's an Omni.
My room is 6 X 7 metres side walls far far away.
Indeed!
Way back when I asked Altec how they QC'd their drivers and they only measured efficiency [n0] with a +/- 0.1% QC tolerance since it quickly 'covered all the bases', so individual specs can be pretty far off and still match up 'close enough' WRT speaker system design, replacing bad drivers, etc., and of the few driver designers I've polled over the years is still in use.
[n0] = [[9.7822 * 10^-10 * Vas * Fs^3] / Qes]
What none told me was how they measured it in a manufacturing plant's noisy environment and once shipped to my locale's distributor they only checked Fs, polarity the times I got to watch.
SPL @ 1W/1m = [112.2 + 10 * log [n0]]
GM
Hey look at this. As soon as I saw this video I thought about your comment regarding how a manufacturing plant measures a driver. In this video, it's the whole speaker. They measure it at 3:48 in the video.
Dali Mentor Menuet | Montaje de los altavoces en la Fabrica en Dinamarca - YouTube
The best mod for those speakers would be to make a digital input to bypass the A/D convertion which is full of noise.
After giving the R162 a solid two weeks in my system I can unequivocally say that I prefer large woofer / waveguide speakers.
The R162 is an excellent small bookshelf speaker, no doubt about it. I had them 8 feet from listening position, 30 degrees out and toed in 45 degrees, practically nothing but a small entertainment stand between them and the captain's chair. But there is one distinguishing factor that cannot be overcome with any combination of exotic materials or EQ, It's the wide dispersion / backwall and sidewall reflections of the smaller speaker that makes it sound like there is more 'noise' in the system. Vocals are less intimate.
That's the best way I can put it, anything less than a large woofer/waveguide just sounds like added noise in the system, it's likely those reflections.
For what it's worth, I also did quick A/B testing with a multichannel amp and an RCA selector.
This little experiment has brought me some peace of mind. I can stop searching for something better. The only worthwhile upgrade that I can see above a pair of SEOS may be the waveguide that Mabat is working on in the ATH4 thread. That or when beam control, a la Lexicon or B&O, trickles down to DIYers.
One last comment: It never ceased to impress me that Geddes was right, again.
The R162 is an excellent small bookshelf speaker, no doubt about it. I had them 8 feet from listening position, 30 degrees out and toed in 45 degrees, practically nothing but a small entertainment stand between them and the captain's chair. But there is one distinguishing factor that cannot be overcome with any combination of exotic materials or EQ, It's the wide dispersion / backwall and sidewall reflections of the smaller speaker that makes it sound like there is more 'noise' in the system. Vocals are less intimate.
That's the best way I can put it, anything less than a large woofer/waveguide just sounds like added noise in the system, it's likely those reflections.
For what it's worth, I also did quick A/B testing with a multichannel amp and an RCA selector.
This little experiment has brought me some peace of mind. I can stop searching for something better. The only worthwhile upgrade that I can see above a pair of SEOS may be the waveguide that Mabat is working on in the ATH4 thread. That or when beam control, a la Lexicon or B&O, trickles down to DIYers.
One last comment: It never ceased to impress me that Geddes was right, again.
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I suspect sound field control will come from Amazon Echo speakers. Amazon could buy Harman with pocket change; $1.5 trillion in market cap vs $7.5 billion. The global voice assistant market is around $6 billion right now (?) and will grow to dwarf the historical home audio market.
The engineer (forgot his name) who designed JBL Pro's CBTs went to work for Sonos. I was surprised he left Harman then I realized Sonos is sound field control plus wireless. He understood the future of audio and I didn't.
Lexicon, Kii, D&D, and Beolab are the baby versions of what what Amazon will wind up developing. In fact, we may not even be able to DIY a speaker equivalent to an Echo because we won't have the cloud computing resources to do DSP on the fly. Unless Amazon web services make that kind of stuff available to the public. Which I guess they might for reasons other than home audio.
I'd bet very inexpensive speakers (supported by low latency wireless cloud services automatically adjusting beam control using computer vision to see you and your room) will match the Beolab performance by 2030. So, $500-$1,000 in 2030 will match the performance of an $80K Beolab from today.
The engineer (forgot his name) who designed JBL Pro's CBTs went to work for Sonos. I was surprised he left Harman then I realized Sonos is sound field control plus wireless. He understood the future of audio and I didn't.
Lexicon, Kii, D&D, and Beolab are the baby versions of what what Amazon will wind up developing. In fact, we may not even be able to DIY a speaker equivalent to an Echo because we won't have the cloud computing resources to do DSP on the fly. Unless Amazon web services make that kind of stuff available to the public. Which I guess they might for reasons other than home audio.
I'd bet very inexpensive speakers (supported by low latency wireless cloud services automatically adjusting beam control using computer vision to see you and your room) will match the Beolab performance by 2030. So, $500-$1,000 in 2030 will match the performance of an $80K Beolab from today.
It is always good to know what you prefer. That was the thought that started this thread.
At one time I thought that the preference for a wide even dispersion vs narrow even dispersion was correlated with the listening room. I.e, some rooms did better with a narrow pattern, others did better with a wide pattern. Referring to the now famous listening experiment: Some rooms would sound better with a JBL M2, others would sound better with a Revel Salon 2.
But now I think that personal preference plays a bigger role than does the characteristics of the room. Even though the majority of listeners will prefer a wide even dispersion, a significant minority will prefer a narrow dispersion.
It is good for us to know which type we prefer.
Oh, the other thing. Amazon Music knows what it will be sending you before you get it. It could adapt your sound field to the style of music it streams.
Another other thing, computers will reproduce music. They'll take an audio production from the Beatles in 1960-whatever and totally recreate it from the ground up. It won't be John Lennon's actual voice, it will be a computer creation of John Lennon's voice. Each song you play will be a custom performance just for you.
There's a text generator called GPT-3 that's writing impressive on-the-fly paragraphs and short dialog right now. Eventually, it could take the Beatles and inject lyrics into a song, like if McCartney made an off the cuff joke in or between songs.
Today, we deal with imperfect recordings. Tomorrow, we won't even have recordings.
Another other thing, computers will reproduce music. They'll take an audio production from the Beatles in 1960-whatever and totally recreate it from the ground up. It won't be John Lennon's actual voice, it will be a computer creation of John Lennon's voice. Each song you play will be a custom performance just for you.
There's a text generator called GPT-3 that's writing impressive on-the-fly paragraphs and short dialog right now. Eventually, it could take the Beatles and inject lyrics into a song, like if McCartney made an off the cuff joke in or between songs.
Today, we deal with imperfect recordings. Tomorrow, we won't even have recordings.
I agree Jim. It certainly does come down to personal preference. It's too bad I didn't have the chance to get some friends together to see what their thoughts were. But I think to really know best one has to sit with it on their own for an extended bit of time.
I guess something like Rundumstrahler nuPyramide 717 von Nubert , esp in its direct mode (though not sure how wide the mid coverage is)
https://www.nubert.de/downloads/test-2019-08-19-nupyramide-717--lite-magazin.pdf
This has crossover freq info
I think a big part of this is what you listen to.
This is something that bugs me about audio shows; they constantly demo their speakers with music that is very forgiving. Nora Jones songs have no bass and not much in the range of dynamics. The presentation of the songs is euphonic and tends to mask any problems.
In the past two years I've rotated through a set of speakers in my living room, everything from the narrow directivity of Bill Waslo's Cosynes, to the wide directivity of the Infinity IL10.
Even after a couple years of daily listening, I can't easily say which one is my fav. For instance the Cosynes excel with good recordings, but bad recording can sound... bad. The Infinity IL10 isn't remotely as pinpoint as the Cosynes but it's more forgiving of bad recordings.
If I had to pick one, it would probably be my Yamahas. Which, ironically, are neither as narrow in directivity as the Cosynes, or as wides as my IL10s. The Yamahas are waaaaaaaaaaaaay more dynamic than any speaker I've ever owned and that probably plays a part too. (Though my Gedlee Summas were similar in design to the Yamaha, I never used more than 50 watts with them. The Yamahas have a built in amp that's 1100 watts :O )
DXR mkII Series - Powered Loudspeakers - Yamaha
My current speakers are similar to yours. I have Infinity IL10s. A few months before that, I had Waslo Cosynes as my reference, which are much narrower in directivity.
I've heard the Beolab 90s a few times, had the pleasure of talking to their designer when they premiered.
I went down to B&O in La Jolla a few months ago to demo the 50s, but they didn't have them hooked up. They *did* have the 90s.
One of the 'neat' things about the 90s is that you can literally dial in the beamwidth to suit the music. It's really neat. For instance, I played "New York" by Lou Reed, and that's really well recorded, and it's well suited to narrow directivity. Next I played an album by "The The" that *wasn't* well recorded. So I widened the directivity, and *poof*, the album benefited from the additional energy of wider directivity.
It's just surreal that you can basically get two completely different presentations, and you can do all of that from a remote control.