But we know that the chances are good that they are responsive.
https://www.youtube.com/watch?v=M3SF3VT0EC0
Hey, man, I'm cheap. My <$100 usd sound card with akm4396 dacs feeding jrc4580's works for me.
Iv'e heard great digital. When the JBL M2 was just lanched Charles Sprinkle sat me down in one of the JBL listening rooms and played his FLAC files. It was good. It imaged like crazy. Still Plastic sounding though. There have been other times. Kevin Gray has great digital playback too.
But I have heard all analog that beats the pants off of ANY digital system.
TechDAS TT feeding a Constellation (another JC masterpiece) Audio system. It's the cost of a house but Wow! Wow! Wow!.
Kevin Gray's mastering room. When he brings out a test cut disk and pops it on his lathe the resolution is not sublte. And if that lathe plays a digitally sourced vinyl cut the soundstage collapses dramatically. I've been in KG's mastering room 3 times for a few hours 2 of those times and one time for 6 hours.
I could go on but I have orders to fill.
BTW 20 years ago I would have told you that digital is the best and SACD will solve all of our audio problems. It just hasn't worked out that way.
Ok - simple subjective opinion then. That's fine - everyone is allowed an opinion...
That brings back a memory of when I was once involved in some design verification of some RF comms gear for which any test transmissions needed to be kept from the outside world (for, shall we say, 'governmental' reasons). Outside door locked, everyone present vetted and cleared, etc. Taking data inside the screen cage with a govt. witness when his cell phone rings......!
That’s correct. I am around the 1uV limit.
Well, no surprises there. Instrument (and music) wise, I am living in the past
http://www.diyaudio.com/forums/atta...jneutron-influence-consequences-1-eq-stds.jpg
You mean same set-up with the source signal level raised to 1Vrms?
If so, I might try with a highish Ohm (above 100mOhm) interconnect.
Cable resistance //3kHz signal voltage drop across cable ends (Vpp/Vrms/dBV)
1mOhm//2.808nVpp/0.993nVrms/-180dBV
10mOhm//28.088nVpp/9.929nVrms/-160dBV
100mOhm //280.732nVpp /99.239nVrms /-140dBV
George
Great test, but since I can't fit in the box, I placed the cell phone in the box and called it. Single layer box it rang. Full double box with insulation it didn't.
I was present at a live recording of Tierney Sutton and Dave Mackay years ago at a supper club. She admonished us to turn off our cellphones, and someone may have been assigned to bar duty to quiet the noisy drunks.
In the middle of a tune a cellphone started to ring. It was in Ms. Sutton's purse.
In the middle of a tune a cellphone started to ring. It was in Ms. Sutton's purse.
Are you aware of how small the received signal actually is on a cell phone in most places? The phones don't talk point-to-point, they go to a repeater (or several) on a tower that is almost always some miles away. Blocking that shouldn't be that impressive.
Let's try 3 each way.
Actually less than a mile to the nearest tower. But the question was asked and it was easy to answer.
On another matter comparing a "Woofer Tester" on long lines to other methods brought up the issue that high efficiency loudspeakers are transducers and thus LRC are not the only issues. Enough noise makes it back into the lines to swamp a low power level sweep. A higher power one will still show a bit of the noise but as it is a smaller percentage of the signal, a better reading results.
Now what is interesting is just about every sound system specification calls for frequency sweeping all of the loudspeakers. Unless you are using a power amplifier based source the results are nonsense and then in a high wind even that isn't bulletproof. Gotta wonder why the consultants haven't noticed. (Except the one I talked to.)
P.S. if you care to play will be doing a stadium in Seattle Monday.
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Thanks for the offer on attending, but that's still hours drive from here, maybe some other time?
Any wind/sound/emi interference should be pretty apparent on an impedance sweep graph, to raise suspicions (as I recall, yours looked very noisy in fact, so point taken).
The output from a Woofer Tester isn't all that small-signal, it is loud enough to clearly hear from a speaker from across the room, I'd guess upper tens of milliwatts, maybe a volt. There is a small power amp chip in the device (though powered from only about 4Vdc, and output through a small series resistor to measure current with).
Any wind/sound/emi interference should be pretty apparent on an impedance sweep graph, to raise suspicions (as I recall, yours looked very noisy in fact, so point taken).
The output from a Woofer Tester isn't all that small-signal, it is loud enough to clearly hear from a speaker from across the room, I'd guess upper tens of milliwatts, maybe a volt. There is a small power amp chip in the device (though powered from only about 4Vdc, and output through a small series resistor to measure current with).
And if I get real energetic perhaps actually measure the power coming back from a 30% efficient transducer in the wind. My bet is it can be a couple of watts. That is based on the amplifier systems that try to measure impedance in use. They come up with nonsense numbers until things get loud. (My idea of loud 1KW peak into the HF!)
Radio Frequency Characteristic Impedance
I'm half a day late, but this Jim Brown paper covers it well.
"Transmission Lines at Audio Frequencies, and a Bit of History"
http://www.audiosystemsgroup.com/TransLines-LowFreq.pdf
Note that the 4 parameters need to be measured at the frequency in question.
Also the strange OCOS cable had low impedance at audio frequencies.
6moons audio reviews: OCOS & Enacom
I'm half a day late, but this Jim Brown paper covers it well.
"Transmission Lines at Audio Frequencies, and a Bit of History"
http://www.audiosystemsgroup.com/TransLines-LowFreq.pdf
Note that the 4 parameters need to be measured at the frequency in question.
Also the strange OCOS cable had low impedance at audio frequencies.
6moons audio reviews: OCOS & Enacom
I'm interested.
I have stated previously that I have observed cable directivity in at least three situations.
Thinking back on those experiences with what I now know, I feel that the cable/system noise spectrum is different according to cable direction, and signal amplitude also.
Dan.
I'm sure you have. I can also identify cable direction 100% of the time.
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