hey all,
newly built set of cnote speakers from PE, both experiencing a HF rise starting around 6.5k
whats good: they both do it, so whatever i botched, i did it consistently, yay!
whats bad: i honestly don't even know where to start digging, and honestly, maybe this just how they are? and there isn't actually anything wrong?
i followed the below diagram to a T. the only variance would be that i was able to get C3 L1 and C4 all to physically intersect without having to have a lead wire between the L1/C3 and C4 (not sure that has any effect) at the common ground
here are my REW measurements of both speakers, again, very consistent between the two (good to see my topping 22 amp is keeping my channels well balanced, shitty pot)
anyway, any help would be great! i have a multimeter if i need to start digging in with that, but pulling the crossovers out would be major surgery as the speaker holes are quite small, and the mounting screws are covered up by the foam lining....
newly built set of cnote speakers from PE, both experiencing a HF rise starting around 6.5k
whats good: they both do it, so whatever i botched, i did it consistently, yay!
whats bad: i honestly don't even know where to start digging, and honestly, maybe this just how they are? and there isn't actually anything wrong?
i followed the below diagram to a T. the only variance would be that i was able to get C3 L1 and C4 all to physically intersect without having to have a lead wire between the L1/C3 and C4 (not sure that has any effect) at the common ground
here are my REW measurements of both speakers, again, very consistent between the two (good to see my topping 22 amp is keeping my channels well balanced, shitty pot)
anyway, any help would be great! i have a multimeter if i need to start digging in with that, but pulling the crossovers out would be major surgery as the speaker holes are quite small, and the mounting screws are covered up by the foam lining....
Attachments
Maybe something changed in the specs of the tweeter.
Doesn't look too bad though. If you're using a pc as a source you can easily eq to whichever curve you want.
Doesn't look too bad though. If you're using a pc as a source you can easily eq to whichever curve you want.
There must be something wrong with the schematic; I searched for cnote speakers on the net and I got the YT video for the mounting procedure: the schematic is the same and there's something wrong with C3. It could go paralleled to C2 to make a 4 uF capacitor, otherwise in that position it's very strange. Curiosly, it should stop HF rise!
I always advise to mount the crossover external and not on the speaker baffle but external far away...
I always advise to mount the crossover external and not on the speaker baffle but external far away...
Cnote xover schematic here
https://www.parts-express.com/pedocs/specs/300-7140--c-note-crossover-with-frequency-response.pdf
https://www.parts-express.com/pedocs/specs/300-7140--c-note-crossover-with-frequency-response.pdf
it would be curious that i have two dud caps in the same position on two separate crossovers, should i meter it to check?
or perhaps there is a wiring issue on my part, i can pull the crossover if need be (which its sounding more and more like i may need to)
A Zobel across the tweeter should help to flatten out the HF rise, roughly 8R in series with 6uF. YMMV
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well, the design is sort of a kit, so i'm not thinking i need to add anything to it. i suppose if the design was wrong, but it's a pretty popular kit
the few places i've managed to find measurements dont seem to have this rise
Mic calibration file maybe ?
Whose idea is the 0.22uF across the bass coil? Its is not in the posted C note schematic in the later link. Although potentially in can be used to suppress a bit of the woofer break up, so it may be a later mod. Unfortunately I don't think it would result in the additional HF problem you appear to have.
I know it sound stupid but maybe double check your wiring of the crossover one more time, and finally does it sound too sharp as not many people can hear to much in that range.
Whose idea is the 0.22uF across the bass coil? Its is not in the posted C note schematic in the later link. Although potentially in can be used to suppress a bit of the woofer break up, so it may be a later mod. Unfortunately I don't think it would result in the additional HF problem you appear to have.
I know it sound stupid but maybe double check your wiring of the crossover one more time, and finally does it sound too sharp as not many people can hear to much in that range.
ugh, yeah, figured i'm gonna have to get dirty and pull the dang thing out or live with it
well, so i posted another REW measurement to ensure this wasn't a mic/setup issue with an entirely different speaker. so i'm hoping no. i also measured with the 90deg (up and down) and straight on calibration file. same results
as for the cap, it was mentioned to use in the forums to reduce woofer breakup, i can remove it as the original design doesnt call for it, although i suspect you are correct, it shouldnt much matter on the tweeter side
and yeah, looking more and more like i need to pull one of these bad boys out to triple check it
What amplifier are you using? This speaker has high impedance towards high frequencies and if it's a class D amplifier without post filter feedback it would result in a potential rise in high frequency output.
uhh, interesting, i'm using a topping tp22 which i believe is a tk2050
let me shoot it over to my denon receiver to see if i can replicate
well i'll be damned, a marked improvement. denon green, tp22 blue
although, compared to the other measurements i can find, seems to not have this issue, and maybe there isnt one...who knows...
below are some other graphs or other folks who i could find with pictures of their measurements and clearly there is a rolloff ~15k (see below)
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finally mustered up the courage to pull the crossovers (main bc it's going to be hell getting the mounting screws back in)
everything looks to spec, but its out, any suggestions on what to check for with the meter? i'm not sure i can measure much with everything connected
everything looks to spec, but its out, any suggestions on what to check for with the meter? i'm not sure i can measure much with everything connected