[Mort]

What is different (better or worse) about "digital" amps? Weight to wattage, the advertised digital units seem quite a bit lighter. Is this something new or just another name for promotional differentiation?


Mort

 

[Swampfox]

I believe these "digital" amplifiers are actually Class D amplifiers, which use output transistors as switches rather than biasing them in the active region. Since the transistor is either "on" or "off", there is a tremendous gain in efficiency. In the past, switching amps were looked down upon, but my guess is that better components and designs have made them acceptable for HT. I have yet to listen to one. The opposite end of the spectrum from a Krell or Pass amp.

 

[Mort]

So I guess they'd be relatives to the products used in automotive applications. Just had noticed that was how Sony was billing their new ES receivers.


Thanks

 

[Greg_R]

Yes, the digital amps are _way_ more efficient (thus requiring smaller transformers and power supplies). The older design's switching resulted in harmonics within the audible range. Newer quality designs have eliminated this issue. I've heard the Bel Canto digital amps and felt they were at least as good as similarly priced A/B designs (but I also feel that most amps sound the same when they are operating in their linear range).