Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems Meridian 258 amplifier first impressions

After having them for a few days, I was finally able to get them installed and fired up.

As far as sound quality goes, for a multichannel amplifier designed mainly for distributed audio, it is truly in a class by itself. Power, authority, speed, pace, dynamics, detail and most any favorable adjective ever read in a review all apply.

The amplifier it replaced was a Russound 1250MC which has served well and is a good multiroom audio amp on its own, is simply crushed by the 258. After driving 4 stereo zones at high volumes that draw scorn from the neighborhood, the amplifier remains room temperature. That said, they can be stacked at will without creating component killing heat thus saving rack space and btu output to deal with.

One thing of note when replacing another amplifier is to watch you polarities. Most any other amp that I have dealt with in the last 40 years, positive is on the left and negative is on the right. On the 258 the opposite is true, positive is left and negative is right.

The amplifier can be triggered via low voltage or from the front panel switch. If power is removed from the mains, the amplifier comes back up in the state it was in previously when power is restored.

The front panel is simply laid out with a single power button and adjacent LED which is blue in standby, white when running and red when in protection mode.

Back panel layout is similarly simple. Nicely spaced, discrete inputs and Phoenix connector speaker outputs, 5-30v trigger connector, and IEC power socket. Voltage is preset at the factory. I am really liking this piece in my system.

Ahem.... 218 or 258? One's interesting, the others just another installers multichannel amp.....

Thanks for your correction. And yes it is an installers amp that actually sounds excellent.

So would you use the amp in a multi channel surround system? An Atmos system with multiple, small drives and powered subs? Is there enough power and depth? Am I alone In thinking it's a miss that you cannot bridge some of the channels?

It is really designed for multiroom, distributed audio, whole house music use, could you utilize it for surround sound/multichannel use? Yes, but on a pretty small scale. Not bridgable, not the intended application.

70W per channel should do the job with sensitive speakers and a medium-sized room surely?

Sure it could. The amp can be used in any way that up to 8 channels can be applied.

Any updates here? Better with age? Looking at the pictures of the interior, it seems lacking. This coming from a guy who built (assembled) his ownHypex NCore amp. Though oddly enough for that, the heft came from the power supplies and not the amps.

What class D platform is the 258 based on? Is it documented anywhere? Hypex NCore amps are superb.

The title was edited to reference the 258 vs the 218. After that at some point, the title at the top of replies has reverted back to 218.
I also noted the comments in the thread about the 258 not being designed to be bridgeable. What constitutes " designed to be bridgeable" or what happens if you bridge 2 channels on an Amp not designed for such?

It has stayed basically the same in terms of sound quality. To me the biggest benefit is how cool it runs. When cranking to whole house audio, the Active Thermal fan never comes on any more. The equipment rack is in a closet in a knee wall space and it used to be the fan ran constantly while the system was on. Now it only runs when the surround amps have been on for a while.

It's not based on hypex, based on what I can see. I would bet it's the B&O ice that M has used before. I wonder how much of this amp is similar to the amps in the DSP speakers?