This review page is supported in part by the sponsors whose ad banners are displayed below
m(ore)AMP. "It's more powerful by using the larger 125ASX2 module in permanent bridge mode, not the BTL-mode
50ASX2 boards of the mINT. From the ICEamp perspective
mAMP uses the same driver circuit. The special part is what happens before in
our new quad Fet buffer which allows our
cross-coupled input to generate a balanced output from either input type
amongst other benefits.
"This versatile new front end creates higher dynamic range from lower
noise and better common-mode rejection. Another key benefit comes from the extra 6dB of gain as a result of the cross-coupled topology. This extra gain is not preferable per se other than the fact that we could now reduce the output level by the same amount to amplify less noise.
"Some may think, 'hmm, you add 6dB, you remove it again, big deal'.
The beauty is that the overall noise floor prior to the level reduction is derivative of what sneaks past the common-mode rejection. It's that residual noise which is lowered by reducing output gain. The upshot of it all is a new input stage capable of driving upwards of 12V
balanced with <0.0007% THD+N and a noise level downwards of 0.000007V without a filter!
"Since we had more real estate in our new
separates, we could also move away from fixed regulators to something more
exotic. To prevent over/under power-supply regulation we employ our new
triple ripple-reduction tracking regulators which were originally found in our highly
praised STP-SE preamp albeit there without yet the tracking section. These new regulators are
capable of setting the optimum output level based on the pre-filtered
unregulated reference level. The latter tends to vary from household to household as it's
based on the actual AC line level which the regulators are powered from.
"The freshly filtered
raw DC reference is used to create the desired output level and
filtered three more times before providing power to any audio circuit segment. The
significance of this is that it provides a maximally clean DC supply level
whilst preventing any chance of a noisy power supply should the AC mains suffer under-voltage conditions.
"Working with ICEpower over the last 13 years, we have learnt many things. Comparing these modules to the prior versions, you will find a smoother warmer sound. I would say that the majority of improvements come from the latest refinements in the ICEpower HCOM modulator which offers extended bandwidth, lower distortion and improved dynamic range.
"Also worth noting is the fact that the amplifier outputs now remain at a ground potential which alleviates many of the implementation hurdles prior ASP series amplifiers posed. Connecting high-level inputs from the amplifier outputs to a subwoofer are now much more viable without the half power-supply-referenced outputs you found in prior models."