glens

Of that I'm sure!

Math absolutely applies, Jeff. You're taking your "artful" experience bypassing inside an amplifier, where the impedance levels are much higher than in a loudspeaker crossover, and stating that the same values of capacitance will "cover the same musical ranges" when as a matter of FACT they absolutely CANNOT!

Jeff, say you've got only a 25 uF cap in series with an 8 Ohm driver. At 800 Hz that cap presents an impedance of 8 Ohms, so that would be the crossover frequency (800 Hz) of your first-order crossover. Staying with that cap alone, if the driver was 16 Ohms, the crossover frequency would be 400 Hz, and 1600 Hz for a 4 Ohm driver. See where this is going? Parallel caps result in increased total capacitance, with the result that the impedance will be lower at any given frequency. Let's do some math. Using two parallel caps, one each 25 uF and 0.2 uF. The 25 alone is 8.0 Ohms at 795.77 Hz and together (25.2 uF), 8.0 Ohms occurs at 789.46 Hz. That's a fairly negligible lowering of the crossover frequency, but that change may be discernible by a well-trained ear. I understand that you'd use the value of 0.2 uF to sweeten a specific range of frequencies, though I forget just where that was. Let's see what's going on at 2500 Hz with this pair of caps. At 2500 Hz they act as parallel resistors of 2.546 Ohms and 318.310 Ohms, for a total of 2.526 Ohms. The contribution of the lower value (the larger cap) represents 99.206% and that of the higher resistance value (the smaller cap) represents 0.794% of the signal passing through to the driver. That is: -0.069 dB through the large cap and -42.004 dB through the small cap. The bypass cap is obviously not contributing anything meaningfully at 2500 Hz! And the ratio stays the same at 15 kHz, so I'll assume it's also the same at 1 kHz. And that's with the largest bypass value you suggested. Obviously the even-smaller caps' contribution will be even smaller. 40 dB down from the main signal has got to be inaudible no matter how highly-resolving a system is!

Jeff, I want you to fashion a setup where the bypass caps can instantly be switched into and out of the circuit. You may use as much 8AWG mil-spec silver-plated wire as necessary, and as high-precision gold-plated-contact switches, too. I'll then come and operate the switches while you listen. I want to see you be able to detect change!

Here we go again with this horseshit. A capacitor starts out at extremely high, approaching infinite, impedance at DC and it drops impedance as frequency goes up. A 0.2 uF capacitor is only "down" to 40 ohms at 20kHz, so how the hell is that going to offer anything worthwhile to the signal content when used in a loudspeaker crossover? 0.02 uF is 400 ohms at 20kHz, and 0.01uF is 800 ohms! Any signal getting through such small-value caps in series with the drivers is going to be several orders of dB below audibility, thus an utter waste of time and money. https://www.allaboutcircuits.com/tools/capacitor-impedance-calculator/

Well, at least they weren't just knockoffs! For sure? Can't stuff like this be 3D printed?

Is your meter in proper calibration?

The model # is 1067485, so after that, I think, comes two digits for the year, then two for the week in that year, then the sequential number which is most unique. Just a guess...

I'd underlined my guess. '85 seems more like "II" territory to me. Can't post a pointer, but I know I've seen the SN decoder on this site.

"They" say the only dumb question is the one that's not asked...

Go to https://YouTube.com and search for "Justin Bieber"? Didn't he do one?

For the remote or for the dog?

The last two numbers of the year are in there somewhere. The possibilities are 67, 74, 48, 85, 51, 18, 85, 51, ...

Agreed with the post immediately above. Beyond that it looks right.

I'd guess any performance alteration derived from that would border very hard on the limits of perception and/or measurement, if it accomplished anything at all beyond maybe lowing the center of mass 1/4".

Certainly no "retention" problem in a loudspeaker crossover.

That NAD amp was likely class-D.

Which statement begs the question "what are you replacing them with, then?"

Can you make sense of a schematic, or a wiring diagram?

I confess I hadn't read that last part before posting a few minutes ago. I was thinking you were tracing graphs you'd just generated. Got it now.

What I was thinking is that the program already has tabulated data. It is, presumably, what it used to generate its graph in the first place. One would think it would be optional to export that data. If not, I believe you said it was free software. Is only half-free or is the source code also available?

I like the "y'all". Especially when it's an "all y'all"! (A particularly great way of saying "each and every one of you"!) I have no familiarity with any of the mentioned models. If there's an "RP"-whatever it'd likely be best. Unless it's an MTM design that's horizontal. Those don't (can't) work right for horizontal spread. How's about 3 of the suggested model? Can they be bought in odd lots?

Step into the 21st century and use your (hopefully GNU/Linux-running, if not why not?) PC to rip the CDs to flac files and serve then up over the network!

Happy belated birthday! Hahaha...

Mumpgrade it?