The "Pimpala" v2 6th order, Team Fi, DC 10k, Juicebox Lithium. 10k Is In!!!!

[Triticum Agricolam]

i feel it somewhat takes that into account when you calculate what the tuning would be with the rear because it has you subtract the length of the front port from the rear port in order to get the correct rear port length. actually as im typing this i understand what your saying about the front port never having to be accommodated for the rear port. hmm interesting. ill have to see when i get to do some testing

Yeah, I'm curious to see what your results are, mine may have just been a fluke. Its always nice to have more data points.

[tboorn]

for sure, i started a Power factor thread a while ago. so itll be nice to bump it up with some new info

[tboorn]

finally got around to doing a little bit of testing, all low power so far since i was working in my garage and it was still shaking shit everywhere. but got some rise numbers for most of the scenarios, forgot to test each individual window down so ill have to add that but its pretty crazy to see how much the rise changes just by opening either door. here's my question though, each way i tested had a different location for the lowest resistance, essentially where the tuning is, so how am i to determine where its actually tuned to by testing if given the setup of the doors, the cars tuning can change significantly. maybe testing impedance isnt the best way to test for tuning but it seems like where the box is most efficient, would also be where the rise is the least... idk check it out for yourself.

[tboorn]

only promising thing i see in all the graphs is that there is two peaks, well dips technically, so it does show the 6th order reacting like it should. as to where the tuning is, beats me haha

[Triticum Agricolam]

Wow, the impedance does really move around a lot based on how you have your doors configured. That does make it a bit tricky to nail down your tuning frequencies.

I've always had trouble trying to accurately determine tuning just by looking an impedance plots. The two other ways I've done it are to use a calibrated mic and put it right next to the cone and do a sine wave sweep. There will be very sharp dips is output at the cone right at the tuning frequencies. I've only used this method with ported boxes though so I'm not sure how it would work out in your situation. The other way, and probably the easiest, is to look at the cone and see what frequency it moves the least. It could help if you were to put something like a little piece of tape hanging off the cone to help you see small movement. I usually just put some sawdust on the cones to detect small movement, but that only works if they are facing up, which obviously yours are not.

FYI, your greatest efficiency it actually where the impedance peaks, since with the impedance so high you are hardly putting any power into the subs at all. You will get the loudest though where your impedance is the lowest though, like you said.

[Neto562]

How is your 10k voltage wise with the juicebox? I have my eyes set on one.

[tboorn]

Wow, the impedance does really move around a lot based on how you have your doors configured. That does make it a bit tricky to nail down your tuning frequencies.

I've always had trouble trying to accurately determine tuning just by looking an impedance plots. The two other ways I've done it are to use a calibrated mic and put it right next to the cone and do a sine wave sweep. There will be very sharp dips is output at the cone right at the tuning frequencies. I've only used this method with ported boxes though so I'm not sure how it would work out in your situation. The other way, and probably the easiest, is to look at the cone and see what frequency it moves the least. It could help if you were to put something like a little piece of tape hanging off the cone to help you see small movement. I usually just put some sawdust on the cones to detect small movement, but that only works if they are facing up, which obviously yours are not.

FYI, your greatest efficiency it actually where the impedance peaks, since with the impedance so high you are hardly putting any power into the subs at all. You will get the loudest though where your impedance is the lowest though, like you said.

yeah, I'm glad we are at least seeing the same thing and I'm not just letting something go right over my head, ill try to do some more testing today or sometime soon and see what i can do. I've definitely seen the tape work really well for testing excursion so maybe illl try that again.

[tboorn]

How is your 10k voltage wise with the juicebox? I have my eyes set on one.

awesome. its by no means magic, we still see low 12s and mid 11s. but thats nothing to worry about with lithium batteries as they have steady output voltage safely into the 8 or 9 volt range. so far wired to .7 with only 1 extra bank of caps, theres has been no hesitation to go full tilt on it all day. and its taking the beating like a champ.

[diegoclass2010]

i need to flow this thread since im in the same boat with 6th orders. i get the same impedance ups and downs... the only think i doesn't get that many spikes since im wired pretty low... .35 ohms... anyways awesome build log i need to get my 6th playing low like yours my drops after completely after 30-32 hz

edit: what kind of graph chart software did you use... im still using pen and paper

[DavidClark]

Thats a neat/ informative graph