Invisible speakers?

[Phelonious Ponk]

I gottcha!

The tweeter and mid ribbons run vertically through a powerful magnetic field their full length. The bass is handled by a huge trapezoidal panel. This is a 1 ohm speaker. My amps and preamp were devised by an owner of the same speaker as I have. They are the only power amps that truly control 1 ohm speakers. The speakers were built in the mid-eightees. The amp technology took another dozen years to come about to match them.

What do you think you've got? You've answered me with a "fact" as unsubstantiated as most of the posts in this thread. Show me independent measurements on the Scintillas that show that they demonstrate flatter frequency response and lower distortion throughout their range than...say...we won't even overshoot this one...a Benchmark DAC1 Pre. Then we'll talk. But you aren't going to find them because if a speaker that good had been introduced in the 1980s it would have been widely copied ever since.

Tim

 

[amirm]

Here is a quick search on distortion of Scintillas: http://www.apogeespeakers.com/reviews/scintilla_hifichoice_1987.htm

"Some sample tests were made for distortion and showed that in the bass, even with a substantial 96dB sound level, the distortion was low at around 1%. At higher frequencies, 0.05 % to 0.1% distortion was typical; these are excellent results."

And the rest of the measurement paragraph:

"LAB REPORT

Due to the difficulties in visiting any anechoic chamber with such a weighty example, some tests were carried out in my listening room. Sensitivity was rather low at 79dB/W, and the watt referred to here is a nominal 8ohms reference, so in truth the Scintilla's efficiency is very low indeed.

Measured close up, the bass panel showed a pretty uniform response which extended down to 20Hz, albeit with a gentle roll off. Similarly smooth results were obtained in the higher frequency range up to 16kHz Between 16 and 17kHz, some interference occurred between the ribbons and the slot aperture in which they are mounted, but no real evidence of related subjective effects were noted during the auditioning. Good integration was shown by the off-axis set of responses, corresponding with the wide driver bandwidths.

The computed listening area in-room response was better than expected in view of the known effect of back wave cancellations. From 40Hz to 16kHz the response was quite uniform, if gently down tilted, with the slight rich tendency we noted. Below 40Hz the bass rose by some 8dB as seen in the 25Hz and 30Hz third-octave bands. How this sounds depends largely on placement and the size of the room.

The impedance curve showed a loading of typically 0.9ohms up to 1.8kHz above which point it improved to around 2.5ohms. Very low resistance speaker cable is essential for best results and to minimise power losses in the connection.

Some sample tests were made for distortion and showed that in the bass, even with a substantial 96dB sound level, the distortion was low at around 1%. At higher frequencies, 0.05 % to 0.1% distortion was typical; these are excellent results."

 

[microstrip]

(...) Cones, domes, ribbons, panels. Bipole, dipole, cardioid or "controlled directivity," they are the weak link, always have been, even when the best electronics were much, much worse than midfi is today. You can deny that, but you'll be very, very lonely, not because the weakness of acoustical transducers is conventional wisdom, but because it is established science. (...)

Tim

Tim,
Here we go again ... What established science confirms your statement? What are the facts? The THD and frequency response?

Although both are imperfect I think that correlations between loudspeaker measurements and what we hear are much better developed and studied than correlations between measurements and hearing in electronics. The myth of perfect electronics is not universally accepted, and there is still a lot to do. Otherwise any one could design a Lamm ML3 costing one hundredth the current price.

BTW I am afraid that some one with good sense will tell that we are comparing apples with oranges ,,,
Neither is the weaker of stronger link .

 

[fas42]

Vince, thanks for carrying the ball while I have been away from the scene! The rest of you, I am afraid, as yet can't appreciate the frustration Vince and I are feeling in trying to get the message through ...

It is not worthwhile becoming obsessed about the Scintilla's performance. As Vince has stated numerous times, there are elements intrinsic to its design that make getting to the illusion a lot easier. Obvious ones, like that there is essentially no suspension that has to warm up and stabilise. I have heard a number of systems using ribbons, and immediately hear the potential there for getting all the the way to a universal sweet spot (it's MY made up expression, I like it, and I think I'll keep using it . It also helps people with the mental image of it).

I have gone with boring boxes, because that's what I can afford, and I can afford to give them a hard time. One of my early rituals in playing with this stuff was to put Status Quo on at maximum volume for an hour or so. There is a lot of crash cymbals going on, good, REAL, high frequency stuff and that nicely warmed up the tweeter suspension and the crossover components. Remember, the key component in between the amp and tweeter in 99% of systems is one of those useless capacitors that all tweakers hate with a passion . What's the point of obsessing about making amps DC coupled if you still end up going through a lousy, cheap cap at the end of the chain -- remember the swimming pool liner analogy!!

Frank

 

[mep]

Frank-Since I do enjoy reading fiction occasionally, your thread has been somewhat amusing. So what have you replaced that "useless" cap hooked to the tweeter with? Without the "useless" cap the tweeter will distort like crazy until it blows up. Since your system is so simple in your words that you could buy it for $5 at a yard sale (you did say that didn’t you?), somehow I doubt you are using an electronic crossover to protect the tweeter.

 

[fas42]

Perfect transparency and imaging, from any position in the room, no matter how close you get to a speaker -- There are a whole lot of reasons why this can't happen, Frank, and a couple of them have to do with the basic laws of physics

It's an illusion, Tim, an illusion. Check out the McGurk effect ...

It makes even bad recordings good -- No, Frank, really, it doesn't.

Bad recordings sound really bad because "nasty" distortion gets into the mix. "Nice" distortion is nowhere near the same problem.

Huhh??!

Take an early 30's big band number , on a typical hifi (not high end) setup, and wind up the volume. There is a big brass section crescendo. Man! THAT'S "nasty" distortion, in spades. Same selection, through a gutsy, well sorted out SET: it will probably sound quite pleasant but a bit thin and nothing, that's "nice" distortion. Those two are not the only options: the other thing you can do is get every last skerrick of that which injects "nasty" distortion into the sound, give your ear/brain half a chance, and the sweet spot will emerge ...

Frank, bud, removing "small distortions"

Tim, I'm starting to get clues that you really like me, better be careful, now

Frank

 

[mep]

I think I get it now. Frank is just pullling our leg and seeing how long it takes to figure out that he is just kidding about everything he said. Frank decided he would say the wackiest things to everyone and see who bit. I think Amir nailed it yesterday with the "1 Thing" video clip.

 

[muralman1]

Amir, that was an 1987 review. As decent a review it was, it is based fully on the inadequate amps of the day. You can't guess what I am listening to based on that review. I can say I have heard the latest Pass amps on my speakers and the sound was not good by my standards. The amps and preamp I have make all the difference power wise. Everything I have in this system operates as a winner's team.

 

[fas42]

Frank-Since I do enjoy reading fiction occasionally, your thread has been somewhat amusing. So what have you replaced that "useless" cap hooked to the tweeter with? Without the "useless" cap the tweeter will distort like crazy until it blows up. Since your system is so simple in your words that you could buy it for $5 at a yard sale (you did say that didn’t you?), somehow I doubt you are using an electronic crossover to protect the tweeter.

Gee, mep, you started off by saying "Wow ...", I'm a bit disappointed now ...

"Without the "useless" cap the tweeter will distort like crazy until it blows up." -- better not tell the folks who are passionate about single driver speaker setups that .... But fair enough, a number of options: put the very, very best capacitors in this critical place, Avalon speakers, etc, etc; an active setup like Tim has, it probably still uses a cap to protect the tweeter from the amp going wacko, but a more sophisticated version would probably dump the the cap and use smart electronic protection; or accept that the components will have to be thoroughly conditoned by heavy driving, before every time you listen "seriously".

Yep, the system is a cheap hand-me-down from the family. I thought, if I can make this sucker do the job, then I am really getting somewhere. And, lo and behold, a single driver setup, no cap, the Fostex crowd would swoon! Yes, one weakness I don't have to worry about ...

Frank

 

[fas42]

I think I get it now. Frank is just pullling our leg and seeing how long it takes to figure out that he is just kidding about everything he said.

Wrong. I am deadly serious. Early in the piece I said to Tim something along the lines of, I only joke when I am serious, just to clear the air. And to repeat, I AM deadly serious. The trouble is, Vince has been trying to get through by being serious, and it hasn't worked: you all enjoy having a gentle dig at what he's saying from time to time.

So, I'm using humour, trying to prod for a weakness in all you people's way of thinking. I am a great fan of the movie "Three Amigos", if that helps anyone understand where I'm coming from ...

Frank

 

[amirm]

Frank, how about you going to Frank's house or vice versa to see if you really agree with each other? No way to be sure otherwise. Right?

 

[fas42]

Frank, how about you going to Frank's house

Hi Frank, it's Frank here, pleased to meet you, Frank

Sorry about that ....

I presume you meant Vince, trouble is, he's halfway around the world from me, I'm in Oz, down under. It probably makes much, much more sense for one of you lot to go to Vince's place and see what you think about it ...

Frank

 

[amirm]

Ah, having been to your part of the world, it shouldn't take much effort to entice anyone to come and visit you there! Best vacation our entire family had was in 1997 in south island.

Now you do know the magnetic field is reverse of here so maybe that has something to do with the current discussion .

 

[fas42]

shouldn't take much effort to entice anyone to come and visit you there

Help, that means that I'll have to clean up the mess it's all in at the moment, you're trying to make me work harder ...

Seriously, people are welcome to come and see if I'm talking bull. Circumstances are a bit down market, because other bits of life haven't worked too well so far, but it doesn't stop the music hitting the heights!

Actually, just noted you were talking about New Zealand, we're next door, Oz is a another way to reference Australia, you might have caught the Oprah show which has us on at the moment

We are all a bit the wrong way here, just ask Paul: "That's not good sound ... THAT'S good sound!"

Frank

 

[Phelonious Ponk]

Tim,
Here we go again ... What established science confirms your statement? What are the facts? The THD and frequency response?

Although both are imperfect I think that correlations between loudspeaker measurements and what we hear are much better developed and studied than correlations between measurements and hearing in electronics. The myth of perfect electronics is not universally accepted, and there is still a lot to do. Otherwise any one could design a Lamm ML3 costing one hundredth the current price.

BTW I am afraid that some one with good sense will tell that we are comparing apples with oranges ,,,
Neither is the weaker of stronger link .

No one is saying anything is perfect or there is not progress to be made, but to get to the example at hand, let's take a look at the measurements of the original DAC1, taken by Peter Aczel in 2005: http://theaudiocritic.com/plog/index.php?op=ViewArticle&articleId=30&blogId=1

As an example, let's just take a look at the ultimate arbiter of accuracy, frequency response throughout and beyond human perception:

Frequency response, both channels: ±0.01 dB from 10 Hz to 6 kHz, –0.2 dB at 20 kHz, –0.5 dB at 30 kHz, –0.9 dB at 40 kHz, and –4.5 dB at 48 kHz.

Find ma a transducer that accurate, even on access, mic'd close. Far enough off axis and away to create a sound stage? Not a chance. I'm not making this up as I go along.

Tim

 

[Phelonious Ponk]

Amir, that was an 1987 review. As decent a review it was, it is based fully on the inadequate amps of the day. You can't guess what I am listening to based on that review. I can say I have heard the latest Pass amps on my speakers and the sound was not good by my standards. The amps and preamp I have make all the difference power wise. Everything I have in this system operates as a winner's team.

So he released an expensive, full-range speaker on the market that could not be driven properly by any amplifier in production at the time? And that's a recommendation? The high-end really is strange...

Tim

 

[MylesBAstor]

No one is saying anything is perfect or there is not progress to be made, but to get to the example at hand, let's take a look at the measurements of the original DAC1, taken by Peter Aczel in 2005: http://theaudiocritic.com/plog/index.php?op=ViewArticle&articleId=30&blogId=1

As an example, let's just take a look at the ultimate arbiter of accuracy, frequency response throughout and beyond human perception:

Frequency response, both channels: ±0.01 dB from 10 Hz to 6 kHz, –0.2 dB at 20 kHz, –0.5 dB at 30 kHz, –0.9 dB at 40 kHz, and –4.5 dB at 48 kHz.

Find ma a transducer that accurate, even on access, mic'd close. Far enough off axis and away to create a sound stage? Not a chance. I'm not making this up as I go along.

Tim

Yeah Mr. Fourier. A bastion of ethics speaks.

 

[Phelonious Ponk]

Tim, I'm starting to get clues that you really like me, better be careful, now

Frank

Frank, I think you're a bit crazy, and I've always had a soft spot for the unstable.

Tim

 

[Phelonious Ponk]

Yeah Mr. Fourier. A bastion of ethics speaks.

I don't get the Fourier reference, but the measurements appear to be valid.

Tim

 

[muralman1]

Tim, we are going to have to agree to disagree. You can't here what I have, so your criticisms of my system make no difference. The Benchmark DAC would sound wretched on this system. There are folks, who heard my system, and with much greater DACs than the Benchmark who would agree with me.