I'm building a small (very small) speaker system for my motorcycle. I have two small 1.5" fronts that mount to the bars plus a sub under the seat. Yes a sub. 
The fronts will be crossed over fairly high to avoid distortion and the "sub" will also be crossed over high to fill in where the fronts can't.
One IC I've been playing with is a TDA8560 which is very easy to work with and has decent power for only a single 12v supply. This is fine for the fronts. Does anyone know of a bridgeable version of that IC or maybe another 30-40w IC that's as simple to wire as the TDA8560? It would be ideal to use the same part# IC because 20w/ch to the fronts blends well with 40w to the sub but it needs to be bridgable in that case.
On another note, I'm sitting here listening to music through some goofy 2" speakers pulled from a Sony TV and a 5w/ch IC amp from some Logitech speakers. I'm a bit taken away by how good this sounds for what it is. Anyway...
The fronts will be crossed over fairly high to avoid distortion and the "sub" will also be crossed over high to fill in where the fronts can't.One IC I've been playing with is a TDA8560 which is very easy to work with and has decent power for only a single 12v supply. This is fine for the fronts. Does anyone know of a bridgeable version of that IC or maybe another 30-40w IC that's as simple to wire as the TDA8560? It would be ideal to use the same part# IC because 20w/ch to the fronts blends well with 40w to the sub but it needs to be bridgable in that case.
On another note, I'm sitting here listening to music through some goofy 2" speakers pulled from a Sony TV and a 5w/ch IC amp from some Logitech speakers. I'm a bit taken away by how good this sounds for what it is.
Anyway...
"bridgeable" as in a stereo IC capable of single channel operation. It's internal topology is not important to me. I can use one IC for the two fronts and another bridged to drive the sub. The sub is 4" and was hard enough to find a decent one let alone one with dual voice coils. I found a DVC 6" but it won't fit.
That's called "mono", not "bridgeable". Misusing terms won't help you get the answers you're looking for.
I think you need to understand what a bridged amp is and how supply voltage is related to power output before you can understand what options best suit your needs.
Another important issue( matter ) is the noise floor (?!? )
A motorcycle in the traffic is different to a room which might be well isolated from external noises . But maybe you intended to listen in a quiet environment ,like parks , woods
In the '80s the good ol' TDA 2009 filled the duties for 2.1 setups in mobile applications , using two subs , so 4 X tda 2009 in total , with a passive HP filter
( 330nF+3k3Ω;100nF+18 KΩ ) for satellites and a mixer + 3rd order lowpass
using a dual IC for the subs .
A motorcycle in the traffic is different to a room which might be well isolated from external noises . But maybe you intended to listen in a quiet environment ,like parks , woods
In the '80s the good ol' TDA 2009 filled the duties for 2.1 setups in mobile applications , using two subs , so 4 X tda 2009 in total , with a passive HP filter
( 330nF+3k3Ω;100nF+18 KΩ ) for satellites and a mixer + 3rd order lowpass
using a dual IC for the subs .
So what is it called when I use a stereo amplifier wired to use both channels to drive a single load?
I understand the supply and load are limiting factors. If I have to I'll build a smps to suit my needs or get a cheap 12 to 24 dc-dc.
If I knew everything I wouldn't need to ask.
Another important issue( matter ) is the noise floor (?!? )
A motorcycle in the traffic is different to a room which might be well isolated from external noises . But maybe you intended to listen in a quiet environment ,like parks , woods
In the '80s the good ol' TDA 2009 filled the duties for 2.1 setups in mobile applications , using two subs , so 4 X tda 2009 in total , with a passive HP filter
( 330nF+3k3Ω;100nF+18 KΩ ) for satellites and a mixer + 3rd order lowpass
using a dual IC for the subs .
The setup I tried for the bike has a TA8210 on the fronts and it was plenty loud for use on a motorcycle. It doesn't take much when the speakers are 18" from my ears. The sub on the other hand will be hard to hear when riding. It's only 4" and I haven't set any design in stone. I have room under the rear fender for two 4" in a sealed tube but there's no way to mount the sub in direct line to my ears. Once I find an IC that will work, I'll try a few positions and see what works best.
I'm not against using a mono IC for the sub. It has to have a minimum of external components. I'm limited on space for the amplifier.
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Here's an example of what I'm sort of looking for.
http://www.datasheetcatalog.org/datasheet/philips/TDA8947J_2.pdf This IC can operate in 4ch mode or bridged as 2+1 or 1+1.
-or-
http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00000164.pdf This IC does 45w into 2ohm 10% THD at 14.4v (If I'm reading the DS correctly)
I don't think I'll get much better then that second link. Minimal components and high power.
EDIT - I just realised I can tap the 3-phase power from the alternator before it hits the regulator and make a dual-rail supply very easily from that. This widens my options greatly. There are plenty of high-power IC kits available that run off of dual-rail supplies.
http://www.datasheetcatalog.org/datasheet/philips/TDA8947J_2.pdf This IC can operate in 4ch mode or bridged as 2+1 or 1+1.
-or-
http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00000164.pdf This IC does 45w into 2ohm 10% THD at 14.4v (If I'm reading the DS correctly)
I don't think I'll get much better then that second link. Minimal components and high power.
EDIT - I just realised I can tap the 3-phase power from the alternator before it hits the regulator and make a dual-rail supply very easily from that. This widens my options greatly. There are plenty of high-power IC kits available that run off of dual-rail supplies.
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I don't know, are the two channels paralleled mono or bridged mono? An amplifier can be mono and still be single ended. Likewise a stereo amp can have bridged outputs, like your TDA8560. It's not "dual mono", it's a stereo BTL amplifier.
No one's saying you shouldn't ask questions, but don't use incorrect terminology and then get defensive when someone tries to explain the different terms.
And to show you I'm not trying to be a ****, I'll suggest one option for higher power without using a higher supply voltage or a lower impedance load.....
www.nxp.com/documents/data_sheet/TDA1562Q_ST_SD.pdf
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Operating that from a 12V suppy in 2.1 mode will give you about 1/4 the power to the highs as you are getting with the TDA8560 since the outputs would be single ended. The BTL sub channel will only give half the power as the TDA8560 since the IC is only specced to drive >8-Ohm loads bridged.
What I know about bridging comes from my car audio days. When a 2 channel "amplifier" drives a single channel, it's bridged. That's all I know. So are these 2ch BTL ICs actually 4ch (of opamps) that are internally bridged into 2ch worth of output? I've found ICs that are 2ch that can be bridged into one. What's different about those?
Anyway we look at it. I'm not any closer to a solution. I need to find a low parts count, 12v, high power, stereo IC that can be bridged to drive a single channel.
"You can't cheat Ohm's law. You either need a lower impedance sub driver (already ruled out), or a higher rail voltage."
To do what? I NEVER stated I needed X amount of power. I'm not trying to cheat anything. There are 1w, 5w, 7w, 10w, 12w, and on and on, ICs out there. There's 1000s of them. Wow you just like to argue facts I'm not arguing about. 20-30w is plenty for a 4" 4ohm sub. If I can fit two of them in there then I'll have 20w x2. I'd just use a 2ch IC or two 1ch ICs.
So here's the question again... What's the highest power, lowest parts count, possibly bridgable 2ch (or single channel) intergrated audio amplifier available? I came looking for IC suggestions not anargument over bridging and ohms law.
Being this is the Chip-Amp thread, I'd assume there are others who have built chip amps that may have some suggestions for ICs that would suit my needs or others to stay away from.
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If you use a Sub that is say 6db more sensitive than your drivers then you don"t need to feed the sub double the power (or use half the impedance) to get the same volume as the drivers ......
There's alot more involved then just driver sensitivity. Box design (sealed, ported, bandpass?) and location are a couple. There's no reflective surfaces like a wall or corner of a room. The openness of the system being installed in a motorcycle makes it more difficult to balance the system response. It will never sound good. It can only sound "good enough".
Getting closer. http://skory.gylcomp.hu/alkatresz/tda1554q_cnv_2.pdf I can run two outputs in stereo and bridge the other two.
Do tell. I'm interested to know if it's something I don't.
Do tell. I'm interested to know if it's something I don't.
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Greetings.
@lazzer408 what you need to understand is that the main factor that limmits the power output of any device is the voltage, unless in class H ( like TDA1562 ) the device can only drive the output signall as much as the voltage let's it do, For example in class AB singlke ended device powered on 12V single supply can only deliver about 7W, maybe 10 max on 4Ohm load, it cannot go higher cus that is the rail level of the signal, and a BTL device would give about twice as that. What you need to understand is that the peak of the wave cannot go higher than 6V ( on single ended device, 12V supply ), it actualy goes less cus some of that voltage is taken by the output devices to go in to on state, and the power output is the maximum possible (Vef^2)/Rload, Vef is voltage rail devided by about 1,41. TDA8560Q has 4 single ended power amplifiers connected inside in BTL config to give at the output only two bridged channels.
The best solution regarding the power output is indeed TDA1562, you could do with your last sugestion too, you would have 2 channels single ended giving a max of about 10W, and 1 BTL of about 20W ( 4Ohm all the way ).
As for a DC-DC converter to rise the voltage level what you need to understand is that although the converter gives the amplifier more voltage and thus more power, it still power up from 12V and the power in at the converter still has to be at least the same as the power out ( that is in the ideal case of 100% efficiency, but it is not ), so if let say you want a multi channel amplifier of for example 2X20W and 1X40W, and so a total of 80W power output for the speakers, that means the power supply unit would have to give about 120W power cus the efficiency of the amplifier is not 100% at all, and more so at the imput of the converter, so botom line is that the 12V potential that will power the whole thing has to deliver much more current, more than 10A in this example, so if you decide to use such method than it would be a good idea first to know what current can you supply the amplifier with and then you can think about how and what to built.
@lazzer408 what you need to understand is that the main factor that limmits the power output of any device is the voltage, unless in class H ( like TDA1562 ) the device can only drive the output signall as much as the voltage let's it do, For example in class AB singlke ended device powered on 12V single supply can only deliver about 7W, maybe 10 max on 4Ohm load, it cannot go higher cus that is the rail level of the signal, and a BTL device would give about twice as that. What you need to understand is that the peak of the wave cannot go higher than 6V ( on single ended device, 12V supply ), it actualy goes less cus some of that voltage is taken by the output devices to go in to on state, and the power output is the maximum possible (Vef^2)/Rload, Vef is voltage rail devided by about 1,41. TDA8560Q has 4 single ended power amplifiers connected inside in BTL config to give at the output only two bridged channels.
The best solution regarding the power output is indeed TDA1562, you could do with your last sugestion too, you would have 2 channels single ended giving a max of about 10W, and 1 BTL of about 20W ( 4Ohm all the way ).
As for a DC-DC converter to rise the voltage level what you need to understand is that although the converter gives the amplifier more voltage and thus more power, it still power up from 12V and the power in at the converter still has to be at least the same as the power out ( that is in the ideal case of 100% efficiency, but it is not ), so if let say you want a multi channel amplifier of for example 2X20W and 1X40W, and so a total of 80W power output for the speakers, that means the power supply unit would have to give about 120W power cus the efficiency of the amplifier is not 100% at all, and more so at the imput of the converter, so botom line is that the 12V potential that will power the whole thing has to deliver much more current, more than 10A in this example, so if you decide to use such method than it would be a good idea first to know what current can you supply the amplifier with and then you can think about how and what to built.
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It's for a motorcycle that has a 3ph alternator and a regulator/rectifier that outputs about 13.2-14.7v depending on RPM. I could tap the 3ph before it hits the regulator and get much higher then 12v but it would be unregulated and I have no idea what the rectified voltage actually is. The other issue is grounding a power supply built that way. I may have to keep the whole audio system isolated to avoid damage to the regulator. I understand the power limitations using a 12v supply and how the load impedance (and output stage voltage swing) limits the available current that can flow to the speaker.
I found another IC TDA8947J www.nxp.com/documents/data_sheet/TDA8947J.pdf
Can you give me your opinion of that vs. the TDA1562? Is there a 4ch SE version of the 1562?
I found another IC TDA8947J www.nxp.com/documents/data_sheet/TDA8947J.pdf
Can you give me your opinion of that vs. the TDA1562? Is there a 4ch SE version of the 1562?
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