Using REW to access new equipment

[rcarlton]

I recently added a McIntosh MC-275 Mk IV to my system, replacing an MC-250 (temporarily, will be used for rear surround speakers once I upgrade my preamp). Used REW to compare before and after curves.

The MC-250 was gone over last year by Terry DeWick and is up to specs.

It is interesting to note in 1970 the MC-250 sold for $379 while the MC-275 was $444. The MC-2505 (blue meters) sold for $449. Now the MC-275 Mk V goes for $3,900.


Finally, Mr. Waddles critically listening to the new amp.

[Chrisbee]

I think Mr Waddles has found a nice new warm spot to enjoy.

Remember to baste well and turn at intervals.

More importantly: What does Mr Waddle's owner think of the new amp?

[Otto]

Ron,

Those are some cool amps! Actually, they might ket kinda warm, but you know what I mean...

In looking at your measurements, there are some significant differences that I wouldn't necessarily epxect from simply swapping power amps. While I would expect different amps to impart a somewhat different character to the sound, I usually find it's somewhat nuanced.

Can you hear the difference? Were the measurements repeatable? I know they're going to get more and more difficult to accurately capture as you increase in frequency. What kind of smoothing did you use on the plots? Just curious. I wonder how the amps would measure electrically. Interesting result!

[rcarlton]

Otto wrote:

Ron,

Those are some cool amps! Actually, they might ket kinda warm, but you know what I mean...

In looking at your measurements, there are some significant differences that I wouldn't necessarily epxect from simply swapping power amps. While I would expect different amps to impart a somewhat different character to the sound, I usually find it's somewhat nuanced.

Can you hear the difference? Were the measurements repeatable? I know they're going to get more and more difficult to accurately capture as you increase in frequency. What kind of smoothing did you use on the plots? Just curious. I wonder how the amps would measure electrically. Interesting result!

I used the 1/3 octave smoothing. Kept all room treatments the same. Would love to try more measurements on other equipment. Can't say I have seen much published data.

I like the sound of the new amps. A little more detailed than the MC-250. The MC-250 is no slouch when it comes to amplifiers, so it is all good.

Piled bass traps around the left speaker to make a pseudo-anechoic chamber. Below are some interesting graphs from this experiment.