I have two questions about battery power on class d amps.
1) When using my sure 7498 boards (either 4 or 6 channel) 3 large SLA batteries, I am getting clipping sounds. It sounds better and louder at 24 volts.
2) When using two inexpensive 12v cctv lithium batteries to power a 2050 class d board (at 24v), my batteries seem to automatically turn off. When I toggle the on off switch on the battery it all fires up again for a while, then kicks off again. Are they not able to run in series?
Thanks for the help, sorry if this is already covered, I couldn't find it.
Tor
1) When using my sure 7498 boards (either 4 or 6 channel) 3 large SLA batteries, I am getting clipping sounds. It sounds better and louder at 24 volts.
2) When using two inexpensive 12v cctv lithium batteries to power a 2050 class d board (at 24v), my batteries seem to automatically turn off. When I toggle the on off switch on the battery it all fires up again for a while, then kicks off again. Are they not able to run in series?
Thanks for the help, sorry if this is already covered, I couldn't find it.
Tor
So the cctv batteries can't run that size of amplifier, or they can't run at 24v?
And does anyone know why my sure boards on SLA batteries are behaving that way?
Thanks, T
And does anyone know why my sure boards on SLA batteries are behaving that way?
Thanks, T
It seems that it has nothing to do with the batteries. I hooked up two car batteries, and it did the same clipping sound. So I wonder whats up.
Iphone out. I've tries all the gain settings. Its unimpressively not loud. worst at 39 volts. 2050 at 24 is much louder and clear. I feel like I'm doing something wrong, but I don't think its my rather feeble iphone output.
The output from iPhones and iPod touches have more voltage swing than most portable devices, but definitely shouldn't be a problem.
Which speakers are you using?
I'm interested in the CCTV batteries - they offer a lot of capacity but the current limiting is an issue. Perhaps some bulk capacitors would smooth out the current demands to something the battery will tolerate?
Which speakers are you using?
I'm interested in the CCTV batteries - they offer a lot of capacity but the current limiting is an issue. Perhaps some bulk capacitors would smooth out the current demands to something the battery will tolerate?
Try a power supply between the batteries and the class D amp, a good SMPS will do the job if you have one. This will isolate the batteries somewhat from the class D switching pulses asnd give you another metric to work with.
Also look at inductances between the batteries and the amp.
Also look at inductances between the batteries and the amp.
chris661 - I'm currently using 4 kicker 6x9 speakers, and a DVC infinity 12" sub. All 4 ohm.
I've had great luck with the 25 watt class d 2020 amp and lithium batteries. ONe common one on ebay even has a usb output as well. 3800 mAh. $18 bucks shipped. The size of a deck of cards. The seem to run into problems when set in series to make 24 volts. I wonder if other 12 dvc lithiums can handle it. I don't know what specification I should look for when buying for such an arraignment.
Marce How big does the power supply need to be? Could one of those scooter 24vdc 3amp power supplies work? They are commonly at the junk stores.
I've had great luck with the 25 watt class d 2020 amp and lithium batteries. ONe common one on ebay even has a usb output as well. 3800 mAh. $18 bucks shipped. The size of a deck of cards. The seem to run into problems when set in series to make 24 volts. I wonder if other 12 dvc lithiums can handle it. I don't know what specification I should look for when buying for such an arraignment.
Marce How big does the power supply need to be? Could one of those scooter 24vdc 3amp power supplies work? They are commonly at the junk stores.
It depends on the system. All battery systems I work on always have a power supply (SMPS) between the battery/batteries and the other electronics. SMPS for efficiency and reduced heat loss. These are all high reliability systems where failure, noise etc are not options. Using an itermediate supply also allows you to controll the power delivery, maximising battery charge and also with additional electronics monitering the battery and with an extra chip or two and a few more bits you can have a battery charger added as well, but that is probably going overboard a bit.
Not at all🙂
Tell me more!
Most lithium batteries lets you draw a lot of current, the bicycle batteries I have here are fused at 40 A, but I made them 20A.
Most amplifiers have capacitors allready to eat spikes.
Of course extra capacitors can be a good idea.
But what do you earn by using a smps? What kind of smps?
I think of in/output voltage.
And how can they monitor batteries & charge them?
I run batteries in series doing +- 72-84V (4 pcs 36V lithium) and I'm running that directly onto the amplifier rails.
Hope it's going to work out!
I have 10Ah 160V or 1600W for an hour, but in my experience most amplifiers never use much power.
"rms" is not continous, even though some claim so, look at a digam 7000, it never pulls more than 1750W and a lab13000 is something like 2300W I think.
So you can expect about x4 in speaker "watts rms" than of what the amp is actually using.
For this I run on 2 pcs hypex ucd2k, 2 pcs ucd700, 21" tapped for sub, double 12" tapped for kick, F2 res2 sh for top.
It's a soundbike by the way.
Hope it's going to work
Tell me more!
Most lithium batteries lets you draw a lot of current, the bicycle batteries I have here are fused at 40 A, but I made them 20A.
Most amplifiers have capacitors allready to eat spikes.
Of course extra capacitors can be a good idea.
But what do you earn by using a smps? What kind of smps?
I think of in/output voltage.
And how can they monitor batteries & charge them?
I run batteries in series doing +- 72-84V (4 pcs 36V lithium) and I'm running that directly onto the amplifier rails.
Hope it's going to work out!
I have 10Ah 160V or 1600W for an hour, but in my experience most amplifiers never use much power.
"rms" is not continous, even though some claim so, look at a digam 7000, it never pulls more than 1750W and a lab13000 is something like 2300W I think.
So you can expect about x4 in speaker "watts rms" than of what the amp is actually using.
For this I run on 2 pcs hypex ucd2k, 2 pcs ucd700, 21" tapped for sub, double 12" tapped for kick, F2 res2 sh for top.
It's a soundbike by the way.
Hope it's going to work
neckro
i hope you are fusing and charging dem batts. safely.
SMPS are used mainly for regulating the battery voltage they operate as constant wattage with delta battery voltage input.
Smart chargers are designed for each cell, much more difficultly with custom strings of cells.
It's four 36V bike batteries, each have a fuse (and an internal fuse) and their own separate lithium charger connected, pics coming when I get the time
All four modules run fine from 4 lithium 36V batteries in first attempt.
Quite a crammed box with 2 mean well smps, all dsp module, plugs, switches & pots, but I did my job thorough.
But one of the ucd2k modules seems to run pretty hot.
It smells hot & gets varm inside the box, even though it's playing at low volume or not playing at all.
Any idea why?
I gues it shouldn't get very warm even without heatsink when it's not playing more than 10, max 20 W or not playing at all.
Tomorrow I'll take it out & check if the heatsink silikone pad has folded or if there's a bad power connection.
The modules are a bit hard working with having pins & heatsink on the same side, I see a lot of people puts heatsinks on the side.
I'll post a forum link to some pictures of the project next week.
Funktion one has supplied two res 2 sh tops for the project.
It's an electric cargo bike with a 21" ground loaded tapped horn, double 12" midbass & turbo tops, should play up to 140 db!
The streets of Copehagen will this at work!
Quite a crammed box with 2 mean well smps, all dsp module, plugs, switches & pots, but I did my job thorough.
But one of the ucd2k modules seems to run pretty hot.
It smells hot & gets varm inside the box, even though it's playing at low volume or not playing at all.
Any idea why?
I gues it shouldn't get very warm even without heatsink when it's not playing more than 10, max 20 W or not playing at all.
Tomorrow I'll take it out & check if the heatsink silikone pad has folded or if there's a bad power connection.
The modules are a bit hard working with having pins & heatsink on the same side, I see a lot of people puts heatsinks on the side.
I'll post a forum link to some pictures of the project next week.
Funktion one has supplied two res 2 sh tops for the project.
It's an electric cargo bike with a 21" ground loaded tapped horn, double 12" midbass & turbo tops, should play up to 140 db!
The streets of Copehagen will this at work!
may you measure your idle current please? 6 hours seems good, I calculated ~9 hours on a 12V/9Ah SLA + 22V step up at max volume (4*50W TPA3132D2) and drum and bass music.
The amp idles at 90mah and begins to clip audibly at 4000mah.
A customer has one my ammoblasters and plays electronic dance music at full volume through 2ohm polk 6x9 speakers. His experience is that a 12v7ah sla battery will last three hours and the 19.2v4ah lithium ion battery will last six hours. He just plays his full blast until the music stops. Only issue is that he cooks the .250 faston connectors every few months and they need to be replaced.
I try to swap batteries before they are more than 70% discharged. Which is six hours on average. The sound quality and quantity is startling.
I find the sla batteries provide more heft in the bass range and the lithium ion batteries provide more punch everywhere. With or without extra stiffening capacitors.
A customer has one my ammoblasters and plays electronic dance music at full volume through 2ohm polk 6x9 speakers. His experience is that a 12v7ah sla battery will last three hours and the 19.2v4ah lithium ion battery will last six hours. He just plays his full blast until the music stops. Only issue is that he cooks the .250 faston connectors every few months and they need to be replaced.
I try to swap batteries before they are more than 70% discharged. Which is six hours on average. The sound quality and quantity is startling.
I find the sla batteries provide more heft in the bass range and the lithium ion batteries provide more punch everywhere. With or without extra stiffening capacitors.
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