Digital Amps ? (1 Viewer)

[StevieP]

Greetings everyone!

I'm curious about the new technology of digital amps, and thought it might be interesting to start a new thread about it!

Being in the marine business (Yacht a/c,& electrical repair/installation)I can't help but try to imagine some kind of comparison to the new technology of marine battery chargers.
The new marine battery chargers, have no transformers, or capacitors. Only a single circuit board, input,& output fuses, and or breakers.

Advantages of the new chargers are:
1) Weight, They are much lighter.

2) They put out stable power, with widely varying input power (Yachts have many AC power challenges including low voltage from long dock runs, and many boats in the same marina all drawing from the same power company transformer)

3)They are very flexible. In that the output can be user tailored for the type of batteries, and ambient operation temps.

4)Quiet operation. Without transformers, or big capacitors the RF noise is reduced (Marine radio transmitters are not affected as much) Also sonic vibration is reduced.

When these new chargers came out, and being a service man from the "old school" train of thought, I Poo-Pooed this new technology to my customers, reasoning that they could not be field serviced, and was not convinced about their reliability!

Now, several years later, reliability, and service do not seem to be much of a problem, and when there is a problem, it's just a matter of popping out a circuit board, popping in a new one, and re-connecting all related wire connectors!

Guy's, I'm no engineer, but it seems to me that there are many similarity's to the challenges of a good amplifier, and that Digital Amps may very well be a viable alternative for the future!

Thoughts, & Ideas ?

STEVE.

 

[Arup]

Digital amps are percieved to be not too musical but for sub applications they are great for all the atttributes you describe above. The Yamaha YST-800/1500 were the first subs to use them and now M&K and Velodyne too have switched to them. Sunfire amps are also supposed to be class D amps so you can see digital is picking up.

 

[MarkO]

http://www.harmankardon.com/product_...201001&stype=S Full steam ahead.

 

[LanceJ]

Have any reputable magazines or Internet sites tested any digital amps/receivers? I keep reading how bad they are supposed to sound but WHO is hearing this?

One other concern: what do digital amps do to hi-res signal sources?

Thanks.

LJ

 

[Chu Gai]

It's a rapidly developing technology. A brief discussion can be found here.

 

[Craig_Kg]

Switching technology can be used in either the power supply or output stages of an amplifier. Most existing designs use a conventional power supply with a switching output (like Trichord) or a switch mode power supply with a conventional output stage (eg Linn and Chord). Very few use switching for both.

 

[Arthur S]

Tact Audio makes about the best digital amps and room correction devices money can buy. Of course their prices are also high.

One electrical engineer (who also designs audio amps) has a problem with digital amps. He says the brick wall filters needed to tame high frequency distortion and noise are audible. The problem is the multiples of 22K. The brick wall filter is at 22KHz to allow for a tested 20Hz to 20KHz response. In order to try to remove the multiples (44K,88K etc.) a brick wall filter is used to cut off frequency response above 22KHz.

Class A/AB amps (the majority of amps) can have unrestricted high frequcncy response, often to over 100KHz (some extend close to 500KHz).

All other things being equal extended high frequency response is desirable. These wide bandwith amps can reproduce virtually perfect square waves across the audible range and beyond.

Having said all that, I would love Santa to drop a Tact amp on me.

Artie

 

[Greg_R]

He says the brick wall filters needed to tame high frequency distortion and noise are audible. The problem is the multiples of 22K. The brick wall filter is at 22KHz to allow for a tested 20Hz to 20KHz response.

Perhaps on older digital amp technology. The newer designs have corrected these issues. Secrets has reviews on various digital amps (search the master index)...