So what do you think of Class D amp for subwoofers

Its been said many times before...its not the class of the amp, its the implementation. We shouldn't compare cheap SS designs with the best SS, nor cheap tube designs with the best, nor cheap early renditions of Class D with the best. Class D was known for its radio interference in its early days. New designs like my Bel Canto are light-years ahead in design. As time marches on, amps designs will continue to improve. Tube has the longest history, SS next, and now Class D. No doubt there will be superb designs of Class D, and new classes of amps in the future, as long as people will buy them. As ong as the amps are working for you, be content. If you upgrade to newer and costlier designs you will hear the difference.

Thank you Grisham, you beat me to the punch! In answer to Bob_reynolds, there are some problems in citing the D-100 review to prove that switching amps are inherently problematic.

1. The review is of a moderately priced amplifier deliberately engineered to meet an affordable price point. D-100 was not intended to redefine the absolute state of the art in monoblock amplification such as Spectron monoblocks, JRDG 312 and 301, Mark levinson No. 54 (hope I got this model correctly).

2. The article is obsolete. It was published in August 2005, probably written about 6 months earlier. . . essentially it is 4 years old, which is a lifetime ago when it comes to the significant strides that the rapidly evolving class D designs are making.

3. From a symbolic logic point of view, the induction step according to which 1 tested amp of a given class having been found to have a flaw, all amps of the same class bear of necessity the same flaw is, . . well. . . flawed itself.

G.

Guido - Issue of the noise came in Stereophile review of Channel Island D100 (Hypex) only because test instruments listen to much wider frequency range than necessary. Yes - all class D amps produce some noise but it is in hundreds of kilohertz - non-audible and not in the FM or TV bandwidth. Any amplifier produces switching noise - even class A or tubes. It comes from power supply (sharp current spikes repeated 120Hz).

As for D100 - it is very good amp. Stereophile says that is "going head to head with an amp as good as the Coda S5". (good class A amp).

Reading your post one would think that D100 is bad sounding or very noisy.

Ah yes, I do remember the discussion. . . tell the truth, I happen to kind of agree with the raw findings of the panel when they reviewed individual amps. . . what I have always problems with is the infimous application of the generalizing induction step. It is worth observing that the amps TAS examined were relatively early products created specifically to meet a particular price point. Most of those products have since then been replaced or enhanced. The Spectron for example, has been significantly enhanced since then. . . recent Spectron entries cost upwards of $22K per monoblock pair with performances to match. The Rowland 201 monoblocks conversely are still current production. They were, and still are the entry level monoblocks of the JRDG product tear and are in consequence designed to meet their price point. JRDG has amps costing upwards of $30K, also with performance to match their price points.

Let us ask ourselves the following: would it be particularly meaningful to promulgate blanket condamnations of the current state of the art in tube amplification, including such extremely high end devices as ARC Reference 610T or VTL sigfried, by generalizing on some supposed shortcomings discovered several years ago in some now obsolete entry level designs?

G.