Midrange dome drivers banned ?

[Brent71]

Did you just stop paying attention to speakers for 30 years?

Nope. I also didn't become a Dunlavy convert until 5 years ago. Show me any speakers built in the past 30 years that have as accurate impulse response, step response, frequency response and phase response as those old Dunlavy speakers. I keep looking at the Stereophile review measurements and every single speaker reviewed pales in comparison to 30 year old Dunlavy designs.

 

[Doodski]

Nope. I also didn't become a Dunlavy convert until 5 years ago. Show me any speakers built in the past 30 years that have as accurate impulse response, step response, frequency response and phase response as those old Dunlavy speakers. I keep looking at the Stereophile review measurements and every single speaker reviewed pales in comparison to 30 year old Dunlavy designs.

Is the test review available online? Can you snap a image of it and post it here so we can see it?

 

[Blumlein 88]

Dunlavy Audio Laboratories SC-IV loudspeaker Measurements

Sidebar 3: Measurements

www.stereophile.com

Dunlavy Audio Labs Signature SC-VI loudspeaker Measurements

Sidebar 4: Measurements As with some other monster speakers—the JMlab Grande Utopia in May '96, for example, and the Jadis Eurythmie II in March—the SC-VI's size and weight precluded measuring it in Stereophile's listening room, where I routinely perform speaker measurements.

www.stereophile.com

 

[Brent71]

Is the test review available online? Can you snap a image of it and post it here so we can see it?

SC-I: https://www.stereophile.com/content/dunlavy-audio-labs-sc-i-loudspeaker-measurements

SC-IV, before it was revised with new tweeters, woofers and tweaked crossovers. After approx pair 215 they were updated: https://www.stereophile.com/content/dunlavy-audio-laboratories-sc-iv-loudspeaker-measurements

SC-IV/A: https://www.stereophile.com/content/dunlavy-audio-labs-sc-iva-loudspeaker-measurements

SC-VI: https://www.stereophile.com/content/dunlavy-audio-labs-signature-sc-vi-loudspeaker-measurements

Unfortunately Stereophile never reviewed the SC-V, which I own, but John Dunlavy claimed it was the most accurate speaker he ever built, and his favorite. So look at those 4 sets of review measurements, and the SC-V is better than all of them.

 

[Penelinfi]

Like what? Their impulse response, step response, frequency response and phase response are about perfect.

Accuracy Paper

Stand up

 

[Doodski]

SC-I: https://www.stereophile.com/content/dunlavy-audio-labs-sc-i-loudspeaker-measurements

SC-IV, before it was revised with new tweeters, woofers and tweaked crossovers. After approx pair 215 they were updated: https://www.stereophile.com/content/dunlavy-audio-laboratories-sc-iv-loudspeaker-measurements

SC-IV/A: https://www.stereophile.com/content/dunlavy-audio-labs-sc-iva-loudspeaker-measurements

SC-VI: https://www.stereophile.com/content/dunlavy-audio-labs-signature-sc-vi-loudspeaker-measurements

Unfortunately Stereophile never reviewed the SC-V, which I own, but John Dunlavy claimed it was the most accurate speaker he ever built, and his favorite. So look at those 4 sets of review measurements, and the SC-V is better than all of them.

I remember these speakers a little bit. Being that they are limited production how are the drivers sourced? They are a serious looking speaker for sure.

 

[Brent71]

I remember these speakers a little bit. Being that they are limited production how are the drivers sourced? They are a serious looking speaker for sure.

Most of the drivers that John used for DAL speakers were Vifa, but there were a few exceptions. The woofers in the early SC-IV were Morel. The woofers in the SC-IV/A and HRCC center were ScanSpeak. The mid-bass in the early SC-VI were Morel, later changed to Vifa; the 15" woofers were custom Eminence. The tweeters were all Vifa, a D27TG-35-06, except for the early SC-IVs that used a D26TG. The 5.5" Vifa mids were the same in the SC-I, SC-III, SC-IV, SC-VI and HRCC center. The 6.5" Vifa drivers used in the SM-I, SC-II, SC-III, SC-V and SC-II.CC center are the same. The 3" upper-mids in the SC-V, Vifa domes in early models, Vifa cones in later models, and the 8" drivers used in the SC-VI, were not used in anything else. Many of the drivers were modified to John's specs; the Vifa tweeters had additional damping material, and the 12" woofers of the SC-V had 6 strips of heavy felt on the cones.

In his earlier Duntech designs he seemed to use a lot of Dynaudio drivers. He said that the earlier Duntech models were nowhere near as accurate as the later DAL models because he didn't have the anechoic chambers and (at that time) the advanced measurement systems that he had at DAL.

Every single driver was measured in an anechoic chamber and all of the parameters entered into the computers. The computers then pre-selected matching sets of drivers to build a pair of speakers. Once the speakers were assembled John would tweak the crossovers in real-time to meet his rigorous specs and tolerances. Only then would he sign off on them and be boxed up for shipment. You'll never find a schematic for Dunlavy speakers (unless somebody did it on their own) because every single crossover had different component values to make up for the differences in the drivers.

 

[Doodski]

You'll never find a schematic for Dunlavy speakers (unless somebody did it on their own) because every single crossover had different component values to make up for the differences in the drivers.

Interesting. That would be time intensive...

 

[Ktacos]

Nope. I also didn't become a Dunlavy convert until 5 years ago. Show me any speakers built in the past 30 years that have as accurate impulse response, step response, frequency response and phase response as those old Dunlavy speakers. I keep looking at the Stereophile review measurements and every single speaker reviewed pales in comparison to 30 year old Dunlavy designs.

We have dsp my dude, you can nail down most of those metrics pretty easily these days.

Show me a dunlavey speaker with good dispersion. The ones linked above all look pretty poor, one looks really bad even.

 

[Blumlein 88]

We have dsp my dude, you can nail down most of those metrics pretty easily these days.

Show me a dunlavey speaker with good dispersion. The ones linked above all look pretty poor, one looks really bad even.

What gives you the idea the dispersion is bad? Unfortunately Stereophile didn't do those tests back then. Otherwise how are you getting this idea?

I do see the SC-1 is measured and looks bad. I also think you are correct, but wonder why you think so.

 

[Ktacos]

What gives you the idea the dispersion is bad?

The off axis data in the reviews linked above, two of the four have off axis data.

This one is just shit.

Not as bad in this second one but still nothing I'd ever consider good.

I guess no one has done better than this in the last 30 years

 

[Blumlein 88]

The reason for the off axis un-eveness is Dunlavy used 1st order or nearly so crossovers to get those good step responses. It also could pass a pretty good square wave straight ahead. The downside of the 1st order crossovers is it creates peaks and nulls off axis with the MTM arrangement. You can also do that with 24 db crossovers, but it likely was harder to do and much more expensive at the time. Spica I believe managed it with some of their speakers that looked not terrible off axis as they used 24 db crossovers and had a good step response. Hales also had some MTM designs that weren't too bad off axis using 18 db crossovers. Their step response wasn't as good.

The Dunlavy, Vandersteen and Thiels could all do excellent step responses and pretty good square waves as they used 1st order crossovers and designed for this with different depths for the drivers. They all were up and down off axis. Such speakers could sound very good vs others of the time in a limited listening area if you positioned them carefully, aimed them carefully, and absorbed some of the worst off axis behavior. The importance of a smooth off axis response was not known at the time.

 

[Mnyb]

The reason for the off axis un-eveness is Dunlavy used 1st order or nearly so crossovers to get those good step responses. It also could pass a pretty good square wave straight ahead. The downside of the 1st order crossovers is it creates peaks and nulls off axis with the MTM arrangement. You can also do that with 24 db crossovers, but it likely was harder to do and much more expensive at the time. Spica I believe managed it with some of their speakers that looked not terrible off axis as they used 24 db crossovers and had a good step response. Hales also had some MTM designs that weren't too bad off axis using 18 db crossovers. Their step response wasn't as good.

The Dunlavy, Vandersteen and Thiels could all do excellent step responses and pretty good square waves as they used 1st order crossovers and designed for this with different depths for the drivers. They all were up and down off axis. Such speakers could sound very good vs others of the time in a limited listening area if you positioned them carefully, aimed them carefully, and absorbed some of the worst off axis behavior. The importance of a smooth off axis response was not known at the time.

I think the current design paradigm is not to sacrifice of-axis behavior for a nice looking step response . As of axis behavior are magnitudes more important, and 1st order xover comes with a bunch of additional issues to add to the bad of axis . If you want both go active ?

I had Thiels for a while they sounded really good .

 

[Ktacos]

The reason for the off axis un-eveness is Dunlavy used 1st order or nearly so crossovers to get those good step responses. It also could pass a pretty good square wave straight ahead. The downside of the 1st order crossovers is it creates peaks and nulls off axis with the MTM arrangement. You can also do that with 24 db crossovers, but it likely was harder to do and much more expensive at the time. Spica I believe managed it with some of their speakers that looked not terrible off axis as they used 24 db crossovers and had a good step response. Hales also had some MTM designs that weren't too bad off axis using 18 db crossovers. Their step response wasn't as good.

The Dunlavy, Vandersteen and Thiels could all do excellent step responses and pretty good square waves as they used 1st order crossovers and designed for this with different depths for the drivers. They all were up and down off axis. Such speakers could sound very good vs others of the time in a limited listening area if you positioned them carefully, aimed them carefully, and absorbed some of the worst off axis behavior. The importance of a smooth off axis response was not known at the time.

I'm aware of the cause, and it's all the same reasons as to why no one uses first order crossovers in any speakers today that are considered competent.

I did consider that at the time the understanding of dispersion was not where it is today, but the poster claimed no one has done better in 30 years which is just silly.

Vandersteen is a speaker brand I have actually heard, the 2c, and it's still one of the most wrong sounding speakers I've ever heard. Even played some mixes I had done myself on them and the they sounded so wrong. I was pleased when Erin reviewed them as I could put data to what I heard, and it seems he heard the same thing.

Friends don't let friends use 1st order crossovers.

 

[Brent71]

We have dsp my dude, you can nail down most of those metrics pretty easily these days.

Show me a dunlavey speaker with good dispersion. The ones linked above all look pretty poor, one looks really bad even.

What do you consider 'good' dispersion? J.D. paid very close attention to polar response and beamwidth when designing his speakers. https://www.stereophile.com/content/loudspeaker-designer-john-dunlavy-numbers-page-2

Atkinson: You talk about accuracy, but so far you've just defined that in terms of the impulse or step response on the speaker's intended listening axis. What about the speaker's power output into the room? That surely has as much effect on the perceived balance as the on-axis performance?

Dunlavy: That's certainly true. We pay an awful lot of attention to the power response of the speaker into the room. Because that's one of the things that permits us to determine whether we're listening to a live instrument, let's say with our eyes closed, in a typical room. We hear two things. We hear the direct sound of the instrument, but we also hear all of the reflected sound, the reflections off of all of the boundaries of the room. And the ratio between that direct sound as a function of frequency and the reflected sound determines to our ears whether we perceive it as being realistic or not.

We spent a lot of time and money, over 20 years ago, doing measurements in an anechoic chamber of the three-dimensional response patterns of 17 different musical instruments, including drums, string bass, cello—we measured a bassoon, a clarinet, a violin. If a loudspeaker's directivity pattern is incapable of emulating the aggregate, the average of the patterns of all of these musical instruments, it will never sound "accurate."

Most musical instruments are almost omnidirectional at low frequencies, as are most loudspeakers, so it doesn't pose a problem. But as you go higher in frequency, to between 100Hz and 300Hz, if you don't get the beam-width of the speaker correct in this range—and by "correct" I mean that it simulates most live instruments—it will add warmth, unnatural warmth, to the sound of voices and musical instruments. It'll make the average male voice sound too chesty, very unnatural. As you go up higher in frequency, if you have a tweeter that radiates too broad a pattern...it's going to produce shrieky sounds, it's going to sound too zippy. I think everyone's experienced that, especially from inexpensive speakers that have a rising high end.

So a good designer certainly knows that he has to pay a lot of attention to the polar response of a loudspeaker.

 

[Purité Audio]

 

[Brent71]

The off axis data in the reviews linked above, two of the four have off axis data.

This one is just shit.

View attachment 403625

Not as bad in this second one but still nothing I'd ever consider good.

View attachment 403627

I guess no one has done better than this in the last 30 years

Did you happen to notice the note that says they were measured at 50", much less than the 10 ft John Dunlavy recommended for minimum listening distance?

 

[Mnyb]

measurement distance for speakers and recommended listening distance are not closely related ?

Edit: all speakers are measured at similar distances .

Edit2: stereophiles measurement's have some limitations would be cool to see a real spinorama , but i think the off-axis mess is real and a part of the speakers design .

Speakers are literally 1000's of compromises, We know more now . Designers of the past acted on their best knowledge at the time . Some of them learn new stuff and continue .

 

[Ktacos]

Did you happen to notice the note that says they were measured at 50", much less than the 10 ft John Dunlavy recommended for minimum listening distance?

Which speaker? I assume the one that looks worse. Doesn't matter, that is more than enough for distance for the mid and tweeter to integrate. You're just making excuses for an obvious issue. The poor interaction between the mid and tweeter are at 3khz after all. It's a speaker, there's no need to get so invested in it that you just ignore reality.
I mean come on my own little bookshelves I made with $14 tweeters and big round overs makes the dunlavy dispersion look pretty bad. Xover at 2.5khz. This shit ain't magic, anyone with the time to learn can execute a great speaker.

In room ~0-60.

His quotes on polars you mentioned just sound dumb to me.

We spent a lot of time and money, over 20 years ago, doing measurements in an anechoic chamber of the three-dimensional response patterns of 17 different musical instruments, including drums, string bass, cello—we measured a bassoon, a clarinet, a violin. If a loudspeaker's directivity pattern is incapable of emulating the aggregate, the average of the patterns of all of these musical instruments, it will never sound "accurate."

Most musical instruments are almost omnidirectional at low frequencies, as are most loudspeakers, so it doesn't pose a problem. But as you go higher in frequency, to between 100Hz and 300Hz, if you don't get the beam-width of the speaker correct in this range—and by "correct" I mean that it simulates most live instrument

Speaker isn't a Cello, isn't a drum set, and certainly not a bassoon. This approach seems quite misguided but not too crazy for the time, people still complain about how speakers don't emulate anything found in nature, as if that matters. Speaker history is full people confusing loudspeakers for instruments and building off that fallacy in hopes of achieving some sort of "natural" sound, the performer is in the room with you sort of nonsense. These people IME tend to have a poor understanding of what goes into capturing instruments and how the sense of "realism" in music has been largely dictated by mixing trends and advancements in reproduction in general.

On a more positive note I do quite like the look of Dunlavy stuff.

 

[Blumlein 88]

What do you consider 'good' dispersion? J.D. paid very close attention to polar response and beamwidth when designing his speakers. https://www.stereophile.com/content/loudspeaker-designer-john-dunlavy-numbers-page-2

One key idea, beyond this being marketing speak, is power response mentioned. That was long considered the optimum goal. One of the things Toole found that was unexpected was the preferred speaker was not designed for flat power response, but flat on axis response with even off axis response. Plus that an uneven off axis response was very audible as an undesirable coloration. It is a shame this was not known to Dunlavy. As a result that was not his goal. The goals he had pushed him away from that and towards some aspects of speakers that human hearing doesn't really care about. Same problem with Jim Thiel and Richard Vandersteen.