Hi All,
i've been lurking around here for while and finally decided to register.
I just received my M28 last week and love it... and i also have a M27 (18 months old).. and i "personally" prefer the sound of the M28 in my system,
As i'm running a 13channel system the plan was to get 2 M27's and then i opted for the M28 for the main channels.
I've been A/B'ing these amps all week and there are many tonal similarities in sound, but i'm finding something extra in what the M28 does for my tastes.
For context, i am running a Marantz AV8805 using XLRs into the NADs and they are driving 3 x Bowers HTM2 D3s (as matching LCRs)
My testing is using mostly music from either CD or Tidal (via Heos).
So before anything, i just wanted to listen to each amp on it's own merits and not based on technical read-outs (i got this amp a few days prior to Amir's M28 report).
Straight away i noticed a change in vocals with a little more forwardness (NOT brightness), but also a slightly more articulate presentation of the spoken words... it was only subtle, but it was there.. the soundstage also seemed a tad wider and deeper and it seemed a little more stable overall.
after playing with the music, i setup my PC with REW and UMIK1 mic and ran the basic sweep tests (that's as technical as i can go)
Below is my centre channel via the M28 (blue) and the M27 (red) run as LARGE (just for this test) and with absolutely no EQ, etc
What this chart isn't showing is that the M28 was 0.5dB louder across the range, so i've dropped it 1/2 dB to match and show any real variances.
I've also applied 1/3 smoothing.
FYI i ran these sweeps several times each and the variance you see from 5kHz and up was essentially the same each time. (and this also occurred with the Front Left and Right channels as well).
Perhaps that slight increase from 4-5Khz range is what i noticed with my above comments.
In a nutshell they are both killer amplifiers, but i personally prefer the sound of the M28, so with Amir's specs being so similar to his M27 specs, it may just come down to personal taste.