No Ford Falcon wagons - their last wagon was pretty uninspiring and they killed it off five years ago - this Commodore Sportwagon is something else. Big car, electric steering with light and sensitive touch, goes like swooooosh. Ford never did anything like it. So you might as well agree. 😀
Cheers, Joe
À propos on LP reply: Gary Galo got me this document:
http://linearaudio.nl/sites/lineara...ins E1 & E4_1978 LP dimensional standards.pdf
Worth a read if only for historical reasons.
Nice EMT BTW!
Jan
Scott
Re 'argument': I refered (from an armchair) to a test that can be done at home with a vinyl test record, a cart/arm/TT, a load resistor and a sensitive mVmeter/oscilloscope.
For a test with a single freq tone from a test vinyl record, I would have to make sure of the actual grove modulation velocity that the cartridge will read. How does the test record documentation specifies the modulation velocity? 0 db relative what? x cm/s peak ? x cm/s rms?, 45 degrees stereo cut? lateral monaural, stereo cut?
0.5mg effective tip mass (*) is a good number for many MM cartridges.
0.3mg was quoted for Shure V15V with boron cantilever, while Technics EPC-100CMK4 is quoted with 0.055*mg. Denon moving coil DL-301 is quoted with 0.270*mg.
If you are willing to use one of your test records, I'd love to read what you've found, I'll take the flame.
George
(*) At mid frequences (around 1kHz), this effective mass is well decoupled from other masses (stationary cartridge and arm). We don't need to consider these other masses.
The real problem for energy balance theoretical calculations is on estimating the amount of incoming energy that will deviate from the shank through the elastic damper bearing and the tension wire toward the static cartridge mass and on to the tone arm.
This deviated energy will be subtracted from the one supplied by the grove modulation, thus the remaining energy that moves the magnet is accordingly reduced (add the other electric motor losses too).
Some useful links:
regarding specifying modulation velocities on test records:
Note on Record Specifications
section 1 to 4, Chapter 17 from the Radiotron handbook:
http://tazzon.free.fr/racine/%C3%89lectronique/Documentation/RDH4/CHAPTR17.PDF
And the good old Shure sum-up:
High Fidelity Phonograph Cartridge - Technical Seminar | Shure Technical FAQ
If there is audible 1KHz from cart vibrating mechanically this is clearly not true, also if this was true the arm in general would make no difference rattling bearings and all. I'm assuming here you are referring to the usual mass/spring effective mass model where the spring is rigidly attached to a mechanical "ground".
Since I have the STR series of test LP's which were very carefully calibrated and have both lateral, verticle, stereo, and mono 1kHz tones, I will try some experiments.
BTW another point by this argument the output at 23.5K load should drop by 3dB, right, or at least enough to keep the 80% from going over 100%?
EDIT - George, anyone comments on filling in the numbers here - https://en.wikibooks.org/wiki/Engineering_Acoustics/Phonograph_Sound_Reproduction
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I wonder if there is a way to get the academic version for diyaudio as 'teaching material' ;-)
jan
Attachments
Actually the National Electrical Code may apply as there is a bit on portable cordage, probably not as it is considered part of an appliance. Now in consumer products listing by an agency such as Underwriters Lab is usually not required. In Los Angeles the fire Marshall does have the authority in a public area such as a trade show, but that actually is unusual.
There were folks who made Neutrik speakercon to AC extenion cord adapters. The very next version of the NEC banned them.
So as much fun as you want to poke at things that seem ridiculous there really are somethings too stupid to be true, but are.
That reminds me of about the most dangerous cable in a lab, an unpolarized line cord terminated in clip leads. Once in a physics lab a guy, who closely resembled the nerdy Kent in the movie Real Genius, decided he needed a signal to display on the lab's only decent oscilloscope, I think a Tek 453. He got the clip lead cord and connected it to the BNC vertical input, I guess with the aid of a piece of wire shoved into the center. He plugged it in, and before the breakers blew managed to destroy the very-special BNC jack, which had to be special-ordered. The repair was done by another grad student who was handy with such things. Later on, when the nerdy guy thought it would be funny to hide the detector crystal needed by the handy guy, the latter instructed the nerd to remove his glasses, and proceeded to punch his lights out.
I used to keep an SMA to ac wall plug adaptor hanging next to my desk (it wasn't really connected inside)
Well that's what you need for electric bananas.
Frank Kelly, when he was at UREI, used to joke about a waveguide-to-fahnestock adapter.
That's good a one! I can imagine plugging that into somewhere unsuspecting piece of equipment and watching the sparks fly.
Based on my early fascination with things electrical, I was given a basket of old appliances and cords and such. The presumption was that I would simply play with them, but one day I brought in an assemblage of things to my grandmother and handed her a mains plug, and asked her to plug it in.
It was loud and sparks did fly before the fuse blew in the basement.
She didn't trust me very much after that.
I have a coffin handy in my DIY room, just next to the chair. There is an advanced CMOS circuit below the coffin that will sense change in weight and trigger VOIP communication to a local funereal company.
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