digital amp

[goodsguys]

Hello and thanks for taking the time to read this post.

Can anyone advise on a good digital amp. I searched google for " digital amplifier versus analogue amplifier " to gain a good knowledge of the subject, I like the idea of being able to insert a digital signal and have it amplified without the need for digital to analogue conversion, essentially keeping it within the digital domain but cannot really find any specific lists of who the best manufacturers are or any model numbers.

I saw the name Tripath on this site and also a few Tripath items on ebay, how do they rank.

Finally I purchased a digital amp out of curiosity (for the car) it did sound different but not particularly better when compared with my Audison lrx 4.300 which is analogue.

For home use i have a analogue quad 405-3, what kind of digital amp should i be looking at as a replacement for this.

Many thanks in advance. John.

[egberttheone]

Well pioneer and jvc has some DDX amplifiers dont know the model number. Search for "DDX" on google.
Tripath is not all digital, as it accepts analog in so it has a DAC build into the pwm modulator for what I understand of it.

[theAnonymous1]

Originally Posted by goodsguys

Can anyone advise on a good digital amp.

What's a digital amp?

[goodsguys]

Hi Thanks for the reply.

In answer to the question: A digital amp amplifies digital audio signals as opposed to an analogue amp which uses dac's to convert the incoming digital signals to analogue before amplification.
There is an improvement in performance to be gained by this procedure. The best kind of dac is no dac at all.

Many thanks.

[theAnonymous1]

Eh, sorry..... I was just trolling. Hadn't had my morning coffee yet.

Originally Posted by goodsguys

A digital amp amplifies digital audio signals.

How do you amplify a digital signal?

Shoot, just trolled again...... must be lunch time.

[john65b]

Oh hell, I'll step in...

The only digital amp I ever had was the Panasonic XR series receivers (XR-45 and XR-50, etc). These indeed were digital amps - that is a digital signal from coax or toslink that is amplified, the converted to analog out to the speakers. The "engine" of this amp was an Equibit chipset which is now part of Texas Instruments.

The Tripath is NOT a digital amp. ICEPower and Hypex are also NOT digital amps. These are Class D amps, not digital amplifiers.

EDIT - Toccata Equibit now has its own Facebook page!!
http://www.facebook.com/pages/Equibit/138536309509581

[cbdb]

Any audio amp with digital ins needs to have a digital to analogue converter before the power amp. People mistakingly call class D amps digital amps. I guess strictly speaking there are no such thing as pure digital audio power amps because the speakers need an analogue voltage. Its like trying to make a pure digital preamp.

[cbdb]

How do you amplify a digital signal?

You use a multiplier and end up with a digital signal with different bits, not more voltage.

[Pafi]

because the speakers need an analogue voltage

Actually not. A quantized signal is digital signal, but if the quantums are small enough then it is heard to be analog.

If you connect MSB (most significant bit) to a speaker, the sound will be very distorted, but amasingly the song is recognisable in many cases. If you add one more bit, with 1/2 weight, the sound will be somewhat clearer, but still digital. Where is the limit?

The difference between analog and digital signal is sometimes the question of viewpoint. A digital circuit can be fed by analog signal and vica verse. And an originally digital circuit can be used to amplify analog signal in some cases (CD4069, 74HCU04).

Digital ClassD amplifier: the FETs can switch only at clock pulses (quantised pulse width).

[nigelwright7557]

Originally Posted by cbdb

People mistakingly call class D amps digital amps.

Class d converts analogue to digital the back to analogue.
This means you have two lots of conversion where errors can occurr.