McIntosh MA5200

I have Dynaudio Special 25's.

Those speakers are easy to drive. If anything, you can make the case that the MA5200 is overkill. The combo should sound fine. I heard the Special 25's several times, and in every case they were paired with an amp that was less powerful than the Mac.

Thanks!

After the above conversation, I decided to check out Dynaudio's web site to see what they currently offer. I did a search and happened to come across a Stereophile review of your speakers. Normally, I don't read reviews, but I just wanted to see what they were using to power the speakers. This is a section from the measurements portion of the review.

"Sidebar 3: Measurements

I estimated the Special Twenty-Five's voltage sensitivity at 89.3dB(B)/2.83V/m, 1dB higher than the specified 88dB. The speaker is specified as a 4 ohm load, but as its impedance plot (fig.1) reveals, it drops to this figure for only a small range of frequencies in the lower midrange. The impedance actually stays above 6 ohms for most of the audioband, which, in conjunction with the generally modest electrical phase angle and the higher-than-average sensitivity, suggests that the Special Twenty-Five is a fairly easy amplifier load."

The only real choice here is if you like the sound of the MA5200. Having enough power for your speakers won't be an issue. Personally, I think it will sound very good. Especially with the built in dac.

@ ZD542: Of course speakers don't have a uniform impedance. 8, 6 or 4 are merely nominal ratings and very few companies ever explicitly state the range. One exception is Martin Logan, where their manuals do state a minimum impedance. A friend who recently purchased a pair of ESL EFX found that they can go down to 1.6 ohms @ 18+ kHz. His Hegel H70 wasn't up to the task even though they state they are stable down to 2 ohms.

The reality is that the MA5200 is designed for an 8 ohm nominal load, not 4. Given how well make Mc is, it won't fail, but it is safe to predict that it won't sound its best either. I have learned from hard experience over many years of listening that matching the transducers to the electronics is about half science, 25% personal preference and 25% blind luck. Some stuff that should sound good doesn't, other stuff is the opposite and sometimes very minor tweaks can make major differences. That's one reason why Mc puts 8, 6 and 4 ohm terminals on their higher end models and publishes stability ranges.

BTW, I have a MC7100, and the manual rates it for 8 and 4 ohms nominal only, with 100 W into 8 and 150 into 4, which is a very different result from the MA5200. I run it bridged, where it's rated for 8 ohms only into a B&W HTM 62 that's 8 ohm nominal with 4.3 minimum. Works beautifully.

Ultimately, Jimmymac will have to make up his own mind, but I tend to be conservative where this kind of money is involved. I don't like do-overs. Go with something rated for the load.