What Amplifier Chip to use?

[nicku1302]

Hey everyone,

I am planning on designing a 50W 2 channel audio amplifier project. I am not very experienced in audio amplifiers and i was wondering if you guys have any suggestions on what good chips are out there that would fulfill this requirement?


Thanks guys

[Dennis5587]

Dual mono with two lm3886's should be enough...

[lanchile07]

Well,I just build an integrated amp with LM3875.the sound is fantastic.this is my experience with LM3875 and I am really happy with it's performance.I strongly recommend it!.

[Dennis5587]

This brings up a good point, its going to get a little personal on your part. What exactly do you plan on doing with this amp as far as you have a couple of decisions.

You can run an integrated amp, meaning the amp is pretty self sustained, has volume control right on the amp

You can run a separate amp and preamp, this gives you a little more freedom, as far as you can later on add a second amp to bi-amp speakers. You can change the preamp to a better or different one if you choose... a lot of options

The last one is pretty much same as last, but slight change, you can run dual mono blocks with a preamp, meaning you have a amp for your left speaker, and a separate amp for your right speaker, as well as a preamp. This is nice because it lowers crosstalk, meaning your right side is all right, no left, same goes for left. However you should use separate power supply's and transformers for each mono block, making them completely separate.

[Nordic]

I second the LM3875 notion...
Only 5 pins to deal with, the rest can be snapped off, and you don't have to deal with demuting pins...

Also, there is something in the sound, I like better than the 3886.

[CJ900RR]

And to ad my opinion to this question, I would go for the LM3886 in inverted configuration. That's because I like the sound of that config best. LM3875 is good, but me personaly prefere the LM3886.

You have to try for your self to find out what you like, both chips is good.

[nicku1302]

[QUOTE]Originally posted by Dennis5587

You can run a separate amp and preamp, this gives you a little more freedom, as far as you can later on add a second amp to bi-amp speakers. You can change the preamp to a better or different one if you choose... a lot of options


From what I understand does this mean I'll have a preamp running to the LM3886 for the 1st channel? Then for the second channel another preamp running to a different LM3886? And does this setup allow the use of only one power supply or does it need seperate power supplies for each channel?

[Dennis5587]

This is basically an integrated amp, but with more options. You can run one transformer for the two channels, have them in one box.

Then for the preamp you can have something as basic as a passive preamp which is basically a stepped attenuator, or a pot controlling the volume of the amps, and a rotary switch for selecting which source you want to listen to.

Or, you could go for an active preamp, like a tube preamp, this would amplify the outputs of the rca's coming out of the preamp and change the sound in slight ways, giving it potentially more of a sound you like....

Last thing I'll say, only because this is the option I like most... having a separate preamp gives you the option of using something like the DCX-2496, which is basically a digital sound processor. You have a preamp for selection of which source to use and volume control. Then you send that signal to the DCX which can then split the signal according to frequency letting you bi-amp your system, meaning have a separate amp for your tweets and woofers. As well as an equalizer and time alignment.

Technically you could always just build an integrated amp, and add a preamp later, but this may come into consideration when designing the case.

Dennis

[sukyone]

Lm3886 Or LM4780