Audio Project Amplifier Speaker Loudspeaker Kit
diyAudio.com diyAudio Forums Archive > Top > Amplifiers > Chip Amps
 
LM4780 and 3886 hifi chips? - Click HERE for Original Thread
samsagaz
hey guys, i was looking into the datasheet of lm4780 and lm3886

and i found that the THD in LM4780 is 0.5% and 0.1% into LM3886.

i think that these numbers ar not good enought for an HIFI amp, right?

and another question.. if i use 2 ICs to create an bridged amp, ill get more THD? or will be the same as if i use only 1?



hope ppl understad me :)
mikelm
some amps with .01% can sound really bad

other amps with 2.0% can sound really good

chip amps if done well can sound pretty good

If you bridge you will have twice the voltage available, so it's good for low voltage supplies and /or Higher impedance loads.

If you speaker are 4 - 6ohms bridging will not be ideal. each chip will see 2 - 3 ohms and chips mostly have limited current levels

Why not start with a single chip and see if you like the sound before you try bridging - the sound charactor does not change that much with bridging

hope this helps
samsagaz
ok, so u think that this kind of CHIPs are better than create an AMP using Transistors?

i was looking into my yamaha receiver today and it use 2SC4468 and 2sc1695 Transistors for the amp.
tschrama
read the datasheet... it seems that at 1Watt both chips perform very similar... THD , at 30W the LM3886 seems a bit better 0.003% v. 0.005 %, but my guess is that the LM3886 and LM4780 are very similar in design and performance...
mikelm
quote:
Originally posted by samsagaz
ok, so u think that this kind of CHIPs are better than create an AMP using Transistors?

Ultimately it depends on what sound you prefer and how much time and money you have spare.

with a chip most the difficult design work, layout and construction is done for you. The chip itself brings some advantages. There are a great place to start and extrememly good value

john linsley hood simple class A is a great class A discrete design see

http://www.diyaudio.com/forums/show...10&pagenumber=1

and

http://www.tcaas.btinternet.co.uk/index-1.htm

for a great AB design look here

http://www.printedelectronics.com/p...cts_aksa55.html


that should keep you busy reading for a while...;)
samsagaz
thanks mikelm


i ll test the 3886 and 4780 after i received it and compare the sound with my yamaha amp.

Page generated in 0.027766942977905 seconds with 17 queries,
spending 0.00981092 doing MySQL queries and 0.01795602 doing PHP things.

Powered by: Search Engine Indexer and vBulletin
Copyright ©1999-2008 diyAudio.com