an ic amp can be a transistor amp, as the ic contains the transistors, they are all just semiconductors.
think about an ic like a circuitboard with every part allready inside and assembled.
i know it a verry crude description, and may not be accurate technically, but the logic is proper.
when you make a discrete amplifier from components, the matching of the components can be a challange that you never face with an ic.
i suggest the lm4780 as an amp chip out of this list.
if your goal is some really heavy deep bass , then the first step is actualy a good driver, and a proper cabinet for the task, the amplifier is the last part to figure out.
it can happen with ease that you don't need more of an amp than the trusty sta540.
it depends on the environment where you want to use it, and the subwoofer you want to drive, and the result you want to acheve (-3dbl point, peak spl, ...)
think about an ic like a circuitboard with every part allready inside and assembled.
i know it a verry crude description, and may not be accurate technically, but the logic is proper.
when you make a discrete amplifier from components, the matching of the components can be a challange that you never face with an ic.
i suggest the lm4780 as an amp chip out of this list.
if your goal is some really heavy deep bass , then the first step is actualy a good driver, and a proper cabinet for the task, the amplifier is the last part to figure out.
it can happen with ease that you don't need more of an amp than the trusty sta540.
it depends on the environment where you want to use it, and the subwoofer you want to drive, and the result you want to acheve (-3dbl point, peak spl, ...)
The "thumping bass" is not really about the amplifier type. It's about the speaker system and its capability to waft ever larger amounts of air around! Use the biggest speaker driver (or two) you can get away with. Remember the size of the box these driver(s) will need will need to be accounted for, too. If using a IC amp, use 4 ohms (or 4 ohms combined if more than one driver)as you'll get more current (= more power) but check the IC ratings at 4 ohms.
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Yes, one must DESIGN the amplifier to suit a range of loads.the amp must be able to drive the given speaker, if the amp can not drie a 4 ohm speaker, then it should not be conencted to one.
Advice to attach a lower impedance load is very bad advice !
is about the worst advice I have seen for a 4780/3886 chipamp.If using a IC amp, use 4 ohms
It would be safe to say: The TDA8932 Datasheet Schematic has better quality bass than either the LM3886 Datasheet Schematic or the TDA7293 Datasheet Schematic.A ClassD amp will normally surpass an LM3886 on bass quality. If you don't need too many watts, try a TDA8932. Best bass I've ever had from a chipamp.
Actually, all three of the parts that I mentioned can be set for the same fantastic bass; so, a limitation of bass quality, does not exist inside the chips.
The limitation is documentation (the older linear chips have generic schemas in their datasheets, with placeholder values instead of application optimized performance).
For 40 watts of rather fantastic quality bass, to an 8 ohm woofer, all three chips mentioned in this post do have a point of awkwardness:
TDA8932:
Thermal management, probably involving a kapton sheet and heatsink as big as the board, some paste and bolts. It can reach 40W usable music power if lightly loaded.
LM3886:
T-Net Inverting, using the component values for LM3875 T-Net Inverting from Decibel Dungeon. This plan is not for tweeters. Under-volt to achieve 40W to 8R with good efficiency.
TDA7293:
I have two nice schematics for it; however, there is still the inconvenience of trimming the gain factor differently for any power voltage difference. Under-volt to achieve 40W to 8R with good efficiency.
So, doing the same job with all three chips, is not difficult.
TDA8932's power circuit will cost at least 20% less; however, the many other costs of a completed amplifier, will swamp that one difference.
Also noteworthy is that by adding ~$2 for an additional chip, TDA7293's capacity goes up to 90W to 4R.
Yes, one must DESIGN the amplifier to suit a range of loads.
Advice to attach a lower impedance load is very bad advice !is about the worst advice I have seen for a 4780/3886 chipamp.
Scuse me folks, it*does* say CHECK THE IC RATINGS AT 4 OHMS at the end....??
Also both ICs alre clearly capable of 4 ohms cursory look at datasheets!
I think the best is a combination of discrete transistors and chip amps:
Project 137-1
This is Rod Elliott's bi-amp design---high quality sturdy transistors for the power-hungry low end and a chip amp for the high frequencies. AND the advantages of an active 24db/octave crossover with bi-amplification!!
Project 137-1
This is Rod Elliott's bi-amp design---high quality sturdy transistors for the power-hungry low end and a chip amp for the high frequencies. AND the advantages of an active 24db/octave crossover with bi-amplification!!
Oh and BTW the LM4780 is now out of production.
I still have a half-dozen tubes (each) of LM4780 LM3886 LM3875 and LM4702.
Try one of these ...
IRS2092 Class D 200W Mono Audio Power Amplifier Amp Assembled Board 1pc | eBay
really hard to beat price/quality on this ... it even has an over temperature control ....
... would keep it at +-50V .. will give some 150W@8 ohm .... not much there not to like ... only the input cap as it is a ceramic ... but for sub, no problem .....
Have one here running at +-40V
IRS2092 Class D 200W Mono Audio Power Amplifier Amp Assembled Board 1pc | eBay
really hard to beat price/quality on this ... it even has an over temperature control ....
... would keep it at +-50V .. will give some 150W@8 ohm .... not much there not to like ... only the input cap as it is a ceramic ... but for sub, no problem .....
Have one here running at +-40V

Did somebody steal your account? Sure, the comment is true, but I want to know why it was watered down. Flu?Better to have said use an 8ohms speaker and that may by careful application of the datasheet information be suitable for lower impedance loads.
It is easy to design transistors amplifier with better specification than LM3886 
If you want build sub woofer amplifier, I suggest to choose transistors amplifier that use symmetrical VAS. Example: Soopky amplifier, Symetri amplifier that design by Ostripper. You can find it somewhere in this forum.
If you want build sub woofer amplifier, I suggest to choose transistors amplifier that use symmetrical VAS. Example: Soopky amplifier, Symetri amplifier that design by Ostripper. You can find it somewhere in this forum.
?????? No results from search. Do you have a link?It is easy to design transistors amplifier with better specification than LM3886
If you want build sub woofer amplifier, I suggest to choose transistors amplifier that use symmetrical VAS. Example: Soopky amplifier, Symetri amplifier that design by Ostripper. You can find it somewhere in this forum.
?????? No results from search. Do you have a link?
Search this thread: http://www.diyaudio.com/forums/solid-state/248105-slewmaster-cfa-vs-vfa-rumble.html
I'm sorry, it must be "Spooky".
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