Bandwidth Limitations Of Class D Amps??

Mitch,

* Certain legacy class D amps, for example the ones based on ICEpower modules, tend to take an excruciating amount of time to break in... Sometimes more than 1200 hours. Until they are stabilized, both bottom ends and treble ends can sound foreshortened, wooden, or even harsh.

* After break in, I have experienced some legacy class D amps to become very musical, while others have remained wooden or "matter of fact". The frequency extension and musicality of the final result may have to do with the details of the amplifier design, such as power regulation, and input isolation, and some amplifier designers may have been more successful than others in working around the idiosyncrasies of the now legacy ICEpower technology.

* The new generation of class D modules may constitute substantial engineering departures from their predecessors, and there is no evidence yet that they suffer of inherent bandwidth limitations.

G.

"After listening to them and also measuring them..."

Hi George, which are the class D amps that you have listened to and measured?

Thanks, G.

Uhrn, George.... I apologize, but I develop stomach cramps whenever attempting to cope with the kafkian use of dangling pronouns... So, wouldn't you mind disambiguating a bit, and churn out some honest to Gaia makes and models, so to alleviate my psycho-somatic angsts?

May I also suggest you rest for a spell your cherished passion for ancient historiography of class D lore -- admittedly of the most guruesque kind: leave your oscillators and spectrum analyzers at home, go out in the field, and treat yourself to some listening of brand new class D amps!

You might find the experience, uhrn... well.... "Veritas'bly" uplifting *grins!*

Hmmm.... Excellent suggestion George... May be I should really invest in some leading creators of novel class D power conversion modules and amps. My ears tell me it would be a "sound" investment... Unfortunately my wife, source of all financial advice, and always to be heeded in such momentous matters, won't "hear" about it... She insists that only blue chips shall do.

Bottomline... I shall undoubtedly remain poor, but at least audiophilically happy.

I shall now leave you to your fascinating conjectures, whilst you pour over ancient tomes of obsolete lore and alchemic apparata.

To echo Lapentas comments, I have reasons to believe that the stereotypical artifacts at the outer ends of the audible bandwitdh that were frequently associated with a number of older class D amps may not be necessarily reflected in recent designs based on much evolved power conversion modules, like the Ncore NC1200 by Hypex.

Case in point is the Merrill Veritas monoblock that I have just reviewed for Positive Feedback on issue No. 68:

http://positive-feedback.com/Issue68/merrill_audio.htm

Once the amps were properly broken in with 1,000 hours of active operations, I did not detect any musical bandwidth limitations, nor any stereotypical class D artifacts with Veritas.

Of course, there are other amps based on Ncore technology (such as Mola-mola Kaluga and ATSAH by Acoustic Imagery) , and other new class D modules other than the Ncore family (such as the Pascal modules). The examination of more examples of new class D amps should confirm or disprove my hypothesis of class D designs having now grown up into general musical adulthood.

G.