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Everything posted by SnowDrifter
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Go ahead and make a new thread so we can better assist you This one's graduating high school https://www.stevemeadedesigns.com/board/forum/11-subwoofers-enclosures/?do=add
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Right on Honestly, bluetooth monitoring is fine. Good keeping an eye on it. However, I do have some concerns about mixing chemistries. Lithium batteries have some pretty wildly different voltage ranges depending on said chemistry Full charge voltages are as follows: - LTO: ~2.8v - LFP(headway): 3.65v - NMC/NCA/LMO: 4.20v My concern with the different configs is that one chemistry might be starved for energy and not reaching full charge - under-utilization. Or, worse, over-charging and risking degradation / fire risk (depending on the chemistry). My other concern is what the alternator charge/temp profile is. Lithium cells are charged CC/CV - charge up to a given voltage and hold it there indefinitely. This differs from lead/acid chemistries which introduce a float charge as the final step, where voltage is held around 13-13.5v after the battery stops accepting current. Stock alternators are designed to either passively, or actively (controlled via car's computer) honor an appropriate charge profile for lead-acid batteries. That's why your voltage is high when the car is cold, then drops when hot. However, this isn't a great approach for lithium as you risk either over-charging when cold, or only utilizing a fraction of the capacity when hot. A good approach here would be to look into external regulation for the alternator - a separate voltage controller for the output that maintains roughly the same voltage both hot and cold. See: Transpo 911-02R. On the topic of chemistries: Honestly, LTO is like... The gold standard for car audio. It excels at high load, high cycles, broad temperature swings, and tends to fail gracefully rather than present a fire risk. That said, they aren't the most energy dense with respect to volume or weight, nor are they the best value per dollar when comparing capacity-per-cost. That said, it's my opinion that if you are looking to expand your bank, look into more LTO rather than introducing other chemistries w/ different voltage requirements to it.
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Capacitors start at 0v. Most battery chargers are 'smart' and don't energize until they see a turn-on voltage. Better ones still can detect between 6v and 12v batteries. Better ones still can reject the charge if a cell in the battery is bad. I'm curious if the unique charge profile of capacitors was confusing your charger and causing it to abort. Location-wise, they should go close to your load - near your amplifiers. Though.... I am a little curious about the battery mish-mash you have going on. Mind sharing details about it? How's your alternator set up?
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What do you mean shutting down chargers? What's the exact model you have? Or pics? What I would do is this: - If they're in a bank, disassemble them to individual capacitors - Use/make a "test light" and connect each capacitor to it, one at a time, to drain them to 0.0v. Can use a brake-light bulb and some alligator clips - Once they're all drained, assemble them to your bank. - Take that same test light, and use that to charge the bank to ~5v - Measure the voltage across each capacitor. No need to disassemble the bank. But they should all be the same voltage. If so, keep charging. If not, then there's some tolerance / bad units in there that needs to be addressed - Keep charging to >10v. Once there, then you can hook up your battery charger to it. Or leave it until it's >12v and safely integrate it into your vehicle's electrical Note: do NOT try and hook up an un-charged super capacitor bank to your vehicle. Powering a dead cap bank is like shorting out your wiring. Huge inrush current, lots of sparks, probably going to blow fuses.
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My "Godlike" Gaming PC Build 2023
SnowDrifter replied to meade916's topic in Computer Talk - News, technology, advice
That 5 gig has me feeling some type of way..... That's internet faster than some SSDs -
CC1 vs SIA-3500, Round 1, FIGHT
SnowDrifter replied to Taxed1's topic in SMD Crossover Callibrator (CC-1) Topics
Explanation and rambling below. tl;dr, speaker outputs are high voltage, amp casing is ground. Treat it accordingly. If everything still works, I doubt there's any long standing damage to either device. A bit of heat shrink isn't a bad idea, or even a fully insulated connector. Will tag @TonyD'Amore so he can see this. Full bridge, half bridge, class D, AB, etc are all the same in this regard The rails on the amp are energized, and the amp casing is, electrically, a ground. Full bridge / half bridge within this context only refers to if the voltage modulation (signal) happens on one terminal, or both. But regardless, they're both energized. They need to be. Having one terminal at "0v" and the other terminal at any other voltage would just be like wiring a battery to your speaker - DC offset. negative/positive doesn't really exist here as we normally think about negative and positive.... It's just to keep phase consistent, so just bear that in mind when I talk about this. Imagine both pos and neg are charged to 40v. How do you move the driver forward? Positive needs to increase to >40v, so that the ΔV is positive. So, if you play a signal that has an amplitude of 20v, your positive would need to be 60v, and your negative would remain 40v. ΔV = 60v-40v=20v. Then on the other half of the sine wave, where the driver needs to move backwards, positive would be reduced to 20v, so ΔV = 20v-40v=-20v. Whether this is done through one of the output terminals, or both, doesn't matter for the sake of this context. The point I'm trying to make is that regardless of the amplifier design, your speaker terminals should be treated as an energized, high voltage source. Hell, the large 12kw+ amplifiers put out more voltage than you'd get at a wall socket. They become a genuine electrical hazard if you start reaching around and fiddling with stuff wile the system is on. -
Make a new thread here and we can get ya sorted https://www.stevemeadedesigns.com/board/forum/11-subwoofers-enclosures/?do=add
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Dude we aren't google. We are people. Please speak to us accordingly.
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Sundown clipping light
SnowDrifter replied to brian85578's topic in Sundown Audio - GREAT Amps/Subs! GREAT Customer Service!
Dude... 2014.... -
Kicker Zx2500.1 Wiring?
SnowDrifter replied to bumassjeff's topic in Electrical-battery- Alternators- Wiring
Dude make a new thread.... 14 years old 🙃 -
Need help with smd dd1+
SnowDrifter replied to regz's topic in SMD Distortion Detector (DD-1) Topics
You'll know if the preamp is weak because the signal light either won't come on, or will flicker. You can sanity check this by setting it through your amp - turn the gain low and see if the head unit distorts. IIRC, some stock radios use a hard limiter of some variety so they won't distort. They just cap gain at a given threshold -
ZVX-8 Qts published not matching calculated
SnowDrifter replied to elhabito's topic in SKAR AUDIO - (READ ONLY ARCHIVE)
Qts is a derived value. 1/Qts = 1/Qms + 1/Qes With that said..... You're correct on there being a discrepancy. Wonder if they pulled values at different times during lab testing or under different conditions (breather hole covered vs. open). If you need accurate values, might be worth your time to free air the things for 2-3 days to get the suspension in steady state, then pull parameters yourself. -
I'm sorry you've had such a poor experience. But this forum is geared more to sales / trades with other SMD members. Not for airing your grievances against some random etailer you found on facebook. This would be best handled through paypal / your credit card company. There is nothing we can do here based on word of mouth from a new member against someone who doesn't have a presence here on SMD.