And I do not follow you. You care about precision of passive components and then you use them in mediocre valve amplifiers and get mediocre measurements like this. You care in passive precision is not helpful here.
That was measurement limited, as you might have gathered reading the article; the caption you included shows that the preamp had better performance than the sound card I was using then. I've upgraded quite a bit in the nearly ten years since that was done*; I hope that perhaps you have more capability now than you did then. I have been frankly too lazy to post updated measurements since this was already way better than needed for inaudibility.
But nice try at sidetracking and avoiding giving data to support your assertion.
* I'm also on my fourth laboratory since then.
edit: It wasn't your assertion, sorry for saying that- it's hard to keep the nonsense straight.
Give me a break, a. Do you NOT think that they will match in frequency response? What I wrong with you? You know, same brand, same part type, 1K-10K, and SAME TOLERANCE?
You missed the sarcasm John ......

I guess I don't follow. Say you comes are being loaded by the atmosphere during a humid day, and let's ignore the fact there so density gradient in your room from cone to wall. Does not this mechanical loading, a change in the effective mass of the cone , not change the electrical network. Also, the effects of this are relative to the volumetric displacement, I.e., a woofer is affected more than a tweeter. Under different conditions one set up might test and sound better and under others, worse.
speakers do vary alignment over environmental variations - so they would be expected to sound different from day-to-day if humans were able to make such comparisons reliably - which isn't possible for really small differences given the very few bits that get get stored in long term memory from our full sensory experience
We were talking about matching resistors. They don't have "comes."
Speakers tend to be used in the same environment, left to right. So any change in one is the same as the change in the other.
Speakers tend to be used in the same environment, left to right. So any change in one is the same as the change in the other.
We were talking about matching resistors. They don't have "comes."
Speakers tend to be used in the same environment, left to right. So any change in one is the same as the change in the other.
But what about the change in resistivity in the cone wire. Does that change your network? Theory vs practical?
4%Let's run the numbers. If you have 1% resistors, the gain can be off from one setup to another by 2% worst case.
Yes, the resistance of the voice coil changes with temperature. This causes the frequency response and sensistivity of a loudspeaker to be different at high power, compared to low power, due to the heat dissipated by the coil itself. It's more of a problem with PA equipment than home audio, though.But what about the change in resistivity in the cone wire. Does that change your network? Theory vs practical?
If the high one is 1% high from nominal and the low one is 1% low from nominal, how do you get that?
Gain isn't set by a single resistor. It's set by the ratio between two resistors. So with 1% resistors, it's possible for the gain of an amplifier to be about 2% higher or lower than nominal. Therefore there can be a difference of up to about 4% between the gains of two such amplifiers.
Way of topic here but does anyone know how to test a hall effects sensor. Three wires, 5 volt power to sensor, ground and sensor signal?
Yes Sy,
Believe it or not there is wire wound around the back of a speaker come. Typically
Know as a voice cool, like a MC cartridge. Known to get hot and even burn up.
Believe it or not there is wire wound around the back of a speaker come. Typically
Know as a voice cool, like a MC cartridge. Known to get hot and even burn up.
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Way of topic here but does anyone know how to test a hall effects sensor. Three wires, 5 volt power to sensor, ground and sensor signal?
Depends on the sensor type. There are analog, threshold and digital out sensors. Do you have a part number?
One audio,
It is a cam sensor for a pontiac v6 engine. Not sure but assume it is just a simple on off circuit counting revolutions.
It is a cam sensor for a pontiac v6 engine. Not sure but assume it is just a simple on off circuit counting revolutions.
Kind horn an, power it up and bring a piece of metal close to the sensor . Look for a corresponding voltage change. Check this out for reference:
http://www.wellsve.com/sft503/Counterpoint3_1.pdf
http://www.wellsve.com/sft503/Counterpoint3_1.pdf
> It's set by the ratio between two resistors.
Assuming perfect active device
As long as open loop gain is high enough, it's a pretty darn good approximation. And thanks, godfrey!
Yes, heating voice coils can change the sound as well. I'm still not following that train of thought. Fortunately, I haven't overheated an MC yet!
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