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What would be a good portable amp chip? Answered

I'm making a simple portable amp, and i'm searching for a good chip. I've already tried LM386 didn't like the sound and power output. TA7368P good sound, but the low frequencies and the power consumption weren't great. (also 741, TL082 but they aren't ideal for amps.) Now i'm with TDA1015 so far the sound is great, power output also great, the consumption is sort of good. Can someone tell me a good mono (or stereo) amp chip that has good power output (>2W) and it has low power consumption. I know it sounds sort of stupid but iv'e seen some great sounding amps with low power consumption and high power output in an old BoomBox. But it was covered by a big heatsink and when i removed it the IC was blank. So if anyone can help thank you in advance.


+10 to all.

Start with efficient, good sounding speakers and you'll be much more satisfied with whatever you use to drive them.

Most common audio amp classes:

Class A - First type used, wasteful of power but supposed to be the most "sonically pure" (no crossover distortion). Efficiency in the 20-30% range +- due to the amp always pushing power through the speaker (or transformer) even if no audio is present. Not good for portability.

Class B - Not used due to the amounts of crossover distortion created, however, they are much more efficient than Class A.

Class AB - What most analog audio amps are. They combine the best qualities of class A and B, relatively high "sonic purity" (minimized crossover distortion) and much greater efficiency, typically over 50% and usually hovering somewhere in the 60% range.

Class D and Class G - Commonly, but incorrectly, called "Digital amplifiers", they combine frequency modulation with pulse width modulation. Without going into deep discussion of their workings, the most important thing to know about them is that they use the PWM to drive the output section so that they are either on or off, no in between. The time that they are on (duty cycle) determines how much power is delivered to the speaker. These usually have greater than 80% efficiency, with the ability to really drain a battery down without losing volume. The typical "MP3 player" uses one of these. Downside is that they are very hard to build from scratch. Kits or factory built are usually best.

From what you've stated originally, you have checked out the obligatory LM386, the TA7368P - low power (450-720mW, depending on speaker and supply voltage) and the TDA1015 (1-4W depending on speaker and supply voltage) along with some general purpose opamps (741 and TL082) that are not power amps, rather they are better suited for preamps. Have you tried looking for “Battery powered audio amplifier IC”. There should be quite a few to choose from. Try Digikey, Mouser, Jameco and MCMElectronics, to name a few, and search for the parameters you want.

2 questions for you.

1.) What is the voltage/current of the power supply you are using or want to use. If batteries, what size (AA, AAA, C, D – 9 volt [PP3] shouldn’t even be considered for this application) and how many.
2.) Are you stuck on using just ICs or are you open to other possibilities such as discrete (transistors) or a combo of ICs and transistors?

Awaiting a reply,

1) Currently i'm using a 9V battery but later on (about 1-2 weeks) i will buy a small battery that's about 12V(or 6V i can just amplify the voltage, would be cheaper but the consumption will be greater.) 6Ah. (The 12V 6Ah costs about 19,9 and is sort of big for this case, the 6V 5Ah costs about 8,9 so it's much cheaper but if i try doubling the voltage the consumption will double i think. But that's just about 200-250 mA that would still give me about 20-30 hours of non stop music.)
I could use Li-ion bateries instead of that big one but that would cost about 30-40 BGN and that's just too much for this project.

2)I've tried lot's of transistor amps (about 73 i think) I've tried from 2t6551 to 2n3055 and anything in between eg. bc640, bc182, 2n5033 and other (the 2N3055 wansn't for a portable amp i just wanted to see the quality and power, and they were awesome but that's not the point now.)

The combinations of IC's and Transistors i've tried are with all the writen amps and some transistors i found laying arround. But i gave up on them because The consumption of some of the amps got to 1.3A and that's just too much for portability. (probably didn't find a good combination)

If you look at the other reply i've written you would see the amp, amp with box and everything and speaker. the speaker is an old Russian one it's about 5W and 8Ohm

And the TA7368P wasn't with the standart schematic i modified it a bit and the power output by my calculations was about 1,1W but there's no way of mesuring it.

I once tried to buld a calss G amp, took me about 3-3.5 hours to get it working, but it was verry unstable. And as for the buying done amp i won't be doing that because the last 4 amps i bought from this store couldn't even start and were about 2-5 BGN more expencive

Awating reply.

Note: Sorry about my gramar and 1$ = ~1.447 BGN

The problem you are running into is that with low voltages, the only way to gain more power is to use more current (amperage). You can use a voltage converter to boost the voltage up, but you actually use more power for the same output because of losses in voltage conversion.

Looking at one of my own amp designs (some of the professionals on the Nuts n Volts board have said that it is one of the more efficient low voltage designs thay have seen), I see that at 12 V and an 8ohm speaker, a 150 mA usage equates to about 185 mW output at the speaker, 200 mA equates to about 325 mW, and 400 mA is about 1.3 W. This design maxes out at about 430 mA and 1.5 W. According to your post below (with speaker pictures - they look like 4"x6" [100mm x 150mm] AlNiCo magnet speakers - love AlNiCo speakers!), you have found that the lower power is actually quite loud. Perhaps you don't really need that much power.

Have you looked at any of the electronics suppliers I mentioned? If you get a "No match" answer using the search terms I mentioned, shorten it to "audio amplifier" and sort through. MCM has some amp modules - just connect and go - and ICs -Sanyo LA4600 is a 12V chip, Jameco has ICs - LM1877 looks promising, Digikey has ICs - LM1896 is a possibility, and Mouser has ICs - TDA2822 pops out at me.

Ultimately, you would have to decide what is best for you. Keep looking and you will eventually find a "best compromise" solution.


Thanks for the info, and the speaker and amp in this config with the TDA1015 and this spk, have the best sound i've heard in some time from a portable amp.

And now the question is if someone could tell me some Tested and well working, stable, cass G(D) amp. I foud a few but i want to know if someone already has a good amp, that has at least >1,2W output (mono or stereo dosn't matter.), good power consumption, and good audio quality.

And as for this stupid furthering of the question i want advice from people who have already tried these amps.

And as for the TDA2822(D2822) i tried but it was sort of unstable as in the quality was verry bad and output and consumption were pretty bad.

You can't HAVE high output power and low input power.
You can get more efficient amps, like the Class G or whatever, which can be >80% efficient, but as Nacho says, the speakers make one HECk of difference to efficiency.
If you were to mess around with "exponential horns" you'd be amazed at how little power you need for a really loud noise, because the speaker is perfectly coupled to the air.

My speaker is from an old Bulgarian( but the speaker was made in !!! (Russia) .) Speaker system. It's ~5W(doesn't say anywhere i think it was about 5W) 8Ohm and it has a great sound... The amp that is currently in use with it is TDA1015 and as far as i have tested it the power consumption can't get over 200mA, at normal volume it's about 30-60mA (depending on the song of course.) but when you crank it up it goes to 100-160mA and it gets VERRY loud. I posted this question becase i wanted to know if anyone knows a good amp with about <200-400mA consumptio, Stereo output with at least 3W per chanel

. Note: the picture is from my amp with the front cover taken off. The others are from the amp and speaker.


A lot of the performance you get from an amp depends on the tone controls and the speaker. You can't get good sound from an amp if you're running a bad speaker.

If you original speaker didn't have good base response then you would not get good sound out of the amp.

. +1. In any decent system, the transducers (speakers, microphones, &c) will have the greatest effect on how good it sounds. Efficient drivers and enclosures will help get the most sound.
. Good bass takes a lot of power even with efficient speakers - no way around it.
. Googling "audio amplifier chip", "10W audio amplifier chip", &c should turn up some good leads. Might want to try replacing "chip" with "module" or other similar words.