Here we have
- Acoustic Active Frequency Filter
- Acoustic Balance Bases
- Acoustic Balance Foam
- Acoustic Cable Tuning System
- Diamond Plugs
- HornResonator with Acoustic SoundBoards, and of course the
- 100% weather-proof Boesendorfer Loudspeaker Cable developed in nuclear physics laboratories in the USA and used by NASA
http://www.bosendorfer-audio.co.uk/files/act_produkt_eng.pdf
Technical Info
http://www.bosendorfer-audio.co.uk/files/technical_folder1.pdf
- Acoustic Active Frequency Filter
- Acoustic Balance Bases
- Acoustic Balance Foam
- Acoustic Cable Tuning System
- Diamond Plugs
- HornResonator with Acoustic SoundBoards, and of course the
- 100% weather-proof Boesendorfer Loudspeaker Cable developed in nuclear physics laboratories in the USA and used by NASA
http://www.bosendorfer-audio.co.uk/files/act_produkt_eng.pdf
Technical Info
http://www.bosendorfer-audio.co.uk/files/technical_folder1.pdf
Yes, they did seem to check all the snake oil boxes. But you forget to mention this gem:
"The Acoustic BalanceFoam are foam objects of approx. 7 mm thickness and extraordinary molecular density."
Wow. Just... wow. It pains me that there are people in this world stupid enough to gobble up this nonsense.
"The Acoustic BalanceFoam are foam objects of approx. 7 mm thickness and extraordinary molecular density."
Wow. Just... wow. It pains me that there are people in this world stupid enough to gobble up this nonsense.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Looks about the same to me.
Actually, your statement is pretty fact-LESS.
I presented the t-line model for a simple length of zip, presented the output of that model with various load values, described how the variation in load impedance changes the settling time of the system, presented that the range of values of those settling times can exceed the human capability of ITD.
Scott then proceeded to model that exact line showing the stepped exponentially decaying waveform that t-line theory predicts (and has been seen on actual test setups), then overlayed an RCL plot which is virtually identical to the t-line model.
While most would come away with "hey, the RCL model validated the t-line model and theory", they would be backwards. What scott has done is validate the RCL model as being of sufficient information to use in lieu of the t-line model. What the RCL model DID NOT DO, is produce the waveform that really exists, the stepped decaying exponential.
The t-line model provides one very useful bit of knowledge that the RCL does NOT. By considering the reflection coefficient and transit time, it is trivially easy to see by inspection, that the settling time is clearly a function of the line to load match. The RCL model does not provide that understanding-by-inspection. Nor, does examination of the RCL model clearly indicate what load impedance will result is ZERO settling time. (Z= sqr(L/C) The t-line model does.
Since the transducer cannot respond to the steps, but rather, integrates it, the RCL model is sufficient to predict the settling time delay.
What scott did NOT do, is continue the analysis, showing how the settling time will be a function of the load resistance. Use the same lumped model, vary the load resistance. Had he done that, he would duplicate the graph I provided in my gallery, which is the prediction of settling time vs load for a constant line impedance USING THE T-LINE MODEL..
Discussion of whether or not the effect is audible is an entirely different story. As speedskater provided, the effect is well within the REPORTED area of ITD discernment, in Gresinger's case, in the field..
It is very important for everybody to understand, the RCL lumped model is a subset of t-line, not the other way around. The RCL lumped model is perfectly acceptable when the information you seek is not lost by using it.
As you can see, statements which are so blatently incorrect do not serve you well, I and others can only form opinions of you based on such, shall we say, untruths?Anyway, turns out he was just trolling after all.
Your brochure lucks the drama.
I see no virgin, no alien, no reference to the centuries required for the formation of these metals by natural processes in the centre of globe (and you mention iron), no mystery, no mysticism.
I see an apologetic style for the cost.
Replace “only” with “as a minimum for the entry version”
George
😀
Darn it. Guess I'll have to sex it up... I did mention niobium titanium, so perhaps I should have invoked near superconducting?
Hey, no backtalk...😉 (couldn't think of anything witty to say)
jn
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But then there's the reality of the final product ... in a demo, the reproduction of piano by their top of the line product was probably the worst I have ever experienced ...
I would like to add that the integration happens at both ends. That is a typical audio PA can not excite the nsec level steps. These steps have frequency content where the characteristic impedance is the high frequency limit. I expect a BW limited step into both sims would look even more alike and again show the same delay. I am trying to get a demo card for our new envelope tracking amps (for cell base station PA's) that will put 20nS, 1A steps into 8 Ohms. (jn, this is what I wanted the resistor for).
To restate my previous point a little differently, I think there is a direct mapping between the RLC model and the L-C from the high frequency characteristic impedance. The actual low frequency characteristic impedance never figures into it.
Scott
Did you make up that signature line just for the snake oil thread? Just like magic cables (or audio transmission lines 😀) some may actually believe it!
Did you make up that signature line just for the snake oil thread? Just like magic cables (or audio transmission lines 😀) some may actually believe it!
No that's from a famous usenet kook Nancy and the planet X nonsense, I think she missed the absurdity of the comment, if the earth stops spinning just where is the safe location. The similarity to a Dr. Bronner's label is probably not a coincidence.
http://www.zetatalk.com/
This stuff gets really funny.
http://www.zetatalk.com/index/zeta349.htm
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I guess you mean that a band limited audio signal played through a typical audio PA -that too is band limited- can not excite the nsec level steps.
I agree with that.🙂
I am very interested to read your results.
Testing with 20ns pulse is like testing with 18MHz sinusoid.
Analog instruments with min. 50MHz BW and digital instruments with min. 90MHz BW (true BW, single shot, not averaging) will be required.
And this assuming a band limited pulse. I am worried with DDS produced pulses.
Test jig HF dragons start showing above 500-700kHZ sinus.
DUT parasitics are but a fraction of test jig parasitics above 1MHz.
I’ve been short circuited with measuring above 10MHz. Characterising the test jig is a nightmare.
I can understand now why National Calibration Laboratories provide cal services for ref standard components only up to 100MHz.
George
I believe what is really missing is this:
The use of a step function is NOT to show the nanosecond level response of the system. It is to show the absolute fastest rate at which the load value can be changed from one value to another. Do NOT get lost or confused by the fact that the step has a fast slew rate. Understand that the primary issue is the load, and how it's value in relation to the line impedance determines the time it takes for a change at the amp to be fully realized at the load.
This step response system settling time does not care what the frequency is, as the settling times we speak of are in the microsecond realm.. forget the low frequency impedance of the cable, that is millisecond timeframes, orders of magnitude AFTER the load has settled to final value.
That is what I designed it for. If you are going to excite that puppy at that speed, unsolder the two power leads and go direct (I used lead tin for the assembly and leads, but you should be able to unsolder the wires without compromising the structure.). The leads' inductance is 180 nH per foot. The bulk resistive structure is roughly 100 picohenries, and the two plates connecting them all will make terminal inductance somewhere in the 250 to 500 picohenry range. The tap leads should see about 5 to 10 picohenries effective Bdot pickup, but I didn't get a chance to do any testing.
If you and your employ require a resistor more tailored to the application, let me know. My cost to you would be 1000 pieces of 1 ohm, 1/4 watt metal film laser trimmed resistors (not mil grade, but the 3 to 6 cent per unit stuff off mouser). I seem to have misplaced mine. I've put together a 3 axis milling platform under my unimat, so I'm closer to drilling brass plate in nice arrays.
My first project will be a pair of 50 milliohm cvr's nestled to either side of a 200 to 1 voltage divider using the same design. But if you have a need, I'll set it up.
I agree on both points, there is a direct mapping. The low frequency characteristic impedance comes into play somewhere in the millisecond realm of the tail of the settling waveform, where we don't care.
They don't interleave currents. Instead, the try to put the v pickup in the magnetic center of the resistor. I sent the designer the info years ago, but never heard back.
jn
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"I believe what is really missing is this:
The use of a step function is NOT to show the nanosecond level response of the system. It is to show the absolute fastest rate at which the load value can be changed from one value to another. Do NOT get lost or confused by the fact that the step has a fast slew rate. Understand that the primary issue is the load, and how it's value in relation to the line impedance determines the time it takes for a change at the amp to be fully realized at the load.
OK, with you here.
"This step response system settling time does not care what the frequency is, as the settling times we speak of are in the microsecond realm.. forget the low frequency impedance of the cable, that is millisecond time frames, orders of magnitude AFTER the load has settled to final value."
Half way through, OK. But as the bulk L and C of the cable limits the BW anyway, it is only the AF range that matters. Please, why should we care what the settling time is for 1MHz or so on a audio cable that won't pass much over 60K or so?
The use of a step function is NOT to show the nanosecond level response of the system. It is to show the absolute fastest rate at which the load value can be changed from one value to another. Do NOT get lost or confused by the fact that the step has a fast slew rate. Understand that the primary issue is the load, and how it's value in relation to the line impedance determines the time it takes for a change at the amp to be fully realized at the load.
OK, with you here.
"This step response system settling time does not care what the frequency is, as the settling times we speak of are in the microsecond realm.. forget the low frequency impedance of the cable, that is millisecond time frames, orders of magnitude AFTER the load has settled to final value."
Half way through, OK. But as the bulk L and C of the cable limits the BW anyway, it is only the AF range that matters. Please, why should we care what the settling time is for 1MHz or so on a audio cable that won't pass much over 60K or so?
edit: put my text in blue for clarity..
You just got through stating "ok with you here", and yet your followup statement means you do not yet understand.
I have time..
jn
L and C do NOT limit the bandwidth in a transmission line, they conspire to set the line impedance.. You have to get past thinking about the problem as bandwidth limited, because we are talking about a delay in the 5 uSec region. Invert that time, and you'll see why. The bandwidth we speak of with those types of delays is ~200 KHz. Haven't you ever purchased scope probes? Back in the day, tek never spec'd bandwidth, they spec'd settling time.
You just got through stating "ok with you here", and yet your followup statement means you do not yet understand.
I have time..
jn
BS and all *S* is chaotic. The more you try to quantify it the more you see the chaos. Chaos is the ideal place to hide a lie. It is so ironic that the wisdom of so many little black books written ages ago do not remotely require the faith often requested. BS is BS no matter how you cloak it, or how you attempt to *explain* the *explaination* turns chaotic and even it resembles a pile of bs. No two piles are symetrical but all are the same.
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#So, you have no response other to attack me
# You can not clearly state what you are babbling on about.
# You can not explain other than you know you are correct why all the text books which clearly describe transmission lines being irrelevant at audio frequencies are incorrect.
# You can not explain why the bulk L & C of a zip cord limits AF at the typical loads it is used at to 60K or so, in disagreement with Self, Cordell, Belden, and my old comunications prof, Dr. Blackwell.
# You can not describe why settling time in the nano-seconds is relevant to audio.
# So you have shifted from nS to uS. Still, you can't explain why even down to 200K it is relevant. We are not building stereos for bats.
Even Monster Cable can sling poop better than that and they only sue competitors, not attack the public.
PS,
Yes, I happen to have a set of P6-106 probes. Very good when looking at 100 Mhz square waves. Settling time and compensation are very important in high speed digital. (that is why their capacitance is adjustable) Funny, right on the probe sticker it says "100Mhz" Come now, you seem to be fairly bright. You can do better than that. 😛
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