Zep...
Best track...Lemon Song.
Owner of the song.....Bassist..
He floats, and floats, and floats...then at 5:36, he gets down to business..he violates nyquist theory with two fingers. THAT type of playing is why I cannot enjoy any cabinet other than a tight folded horn. Reflex cabinets cannot get out of the way fast enough for one to appreciate it.
Were I a musician, I would have been unable to play, as I would have stopped playing, turned, put down my instrument.... and retired.
jn
At the moment, i am doing some mods to decrease distortion from ultra-low THd audio signal generators. The circuitry uses R and c parts and attenuators/pots. Sometimes a change makes a difference with the passive parts but on the whole, they can be extreamly low in thd. Right now I am at the -140 level (THD) with noise (real thermal noise... not FFT floor) at about -155-160db and the only harmonics are from active circuits. So the passives CAN be an issue at extreamly low thd levels (below -90dB re 1V) but they can also be reduced with best available parts to unmeasurable levels. But you need to be able to measure to know which is good and which isnt. IMO--- stay below 10K Ohm and conservative ratings and you are fine. Much above 10K or high voltage/current levels and you should measure to be sure.
THx-RNMarsh
THx-RNMarsh
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John, you always use the same type of perverted reasoning: You take a phenomenon in a given context, and you apply it as a general law, in contexts where it does not apply anymore the same way.
I was just curious about the state of linearity with common IC resistors. I have been looking at this problem for the last 45 years. Maybe, things got better. '-)
John,
Stupid question on my part, but how do you know that the non-linearity you speak of is from the resistors in the IC's? Couldn't any non-linearity have other causes?
Stupid question on my part, but how do you know that the non-linearity you speak of is from the resistors in the IC's? Couldn't any non-linearity have other causes?
Non-linearity comes from ALL components. Please think it through. Right now, you guys are about 30 years behind me in understanding. Is it going to stay this way?
They don't matter, they would have to have percents of nonlinearity over a very small voltage range to even get close to the Vbe change with current. Look at Samuel Groners measurements, not much there. John, you're grasping at straws.
Because an OPA is mainly composed of active devices and resistances. As their active devices are of the same kind than the discreet ones, John need to find an other evil to justify the death sentence applied to ICs.
The only probleme is it seems the execution occurs every morning at dawn, and the condemned seems to be well and alive.
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I hope so. Without being disagreeable, it seems to be about the time you been discontinued to analyze things properly.
Yes and at even lower power levels you might get another zero in there. So lets go to -250 db for the 16th order thd from resistors in a well designed SYSTEM.
I noted RNM gets basically the same results chasing low noise and distortion in oscillators. Dick I trust you are aware capacitors are slightly more of a problem and they should be mounted so the plates are perpendicular to the axis of motion (particularly if there is any DC on them.)
Pavel when I use the AD797 for microphone preamps I get the best results using one as a fixed 9-19 db gain stage and a second as a 0-45(or 10-55) db gain stage followed by an output buffer. What I am playing with is if it works best with all local stage feed back, or two stages with an added loop or overall feedback. The final preamp needs a gain from 25 to 70 db.
BTY the input transformer gives 6 db of gain for those who were counting.
ES
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