New Rotel 7 channel Digital Amp with RF7 surround setup

[JewishAMerPrince]

I remember years ago one of the manufacturers billed their amp as a straight wire with gain. That would be the ultimate amp, as it would add hardly anything in terms of distortion and noise and would loose very little as well. When I opened the box for the RMB 1077 and took out the diminutive device inside that ancient sound bite came to mind.

We are taking a giant leap towards the ultimate amp: A straight wire with gain. Ive spent the past 5 days burning her in and playing all types of source material, with my RF7s (DeanG moded) and offer the following observations:

The 1077 is definitely a Rotel in sound signature, clean, clear and musical. However, it has much more of the mid and low end weight and forwardness of the Krell Showcase or a Halo. The mid and low bass are much stronger than what I am used to experiencing with my 1080 making the 1077 sound like a much more powerful amp. The Halo A21&51 that I tested, with its 250 wpc has similar weight in the low end. The top end is very extended without being bright. The 1077 is less rounded than most Rotel amps, it is also much more transparent then the Halo, whos top end is so rounded that it seems to be designed specifically for brighter speakers that have hot tops, or for people whos high frequency hearing is already shot from too many years of high SPL listening.

When I first turned it on the 1077 was a bit harsh at the top. Sibilant sounds grated like sandpaper. Over time she has smoothed out considerably. This initial harshness is a characteristic I find of all Rotel amps with all Reference Series. After break in the overall sound signature of the 1077 is as close to perfect as I can imagine for use with MY speakers. The Krell Signature 5 channel amp I borrowed last year left a similar impression.

I wouldnt have expected an amp with a FTC rating of only 100 wpc to be so powerful. I think this new breed of amps will have to come along with a new way of defining amplifier power. AMD had to do this a few years back when its processors performed on the level of much higher clock speed Intel processors. AMD started to rate their processors at Intel equivalent clock speed, rather than true clock speed. On day 3 I cranked up the 1077 for a rendition of the "Stars and Stripes" played by the Boston Pops to a level that could be heard by just about the entire neighborhood. I didn't experience any "compression" of the sound as I would expect from an amp sporting only 100wpc (and have experienced with my 1075 while driving the mains). Ive played some heavy material since at insane SPL and the 1077 has handled it all without the slightest hint of clipping or other signs of distress.

Although they are very efficient, the RF7s are a somewhat difficult load since they have an impedance dip to 2.8 ohms at some frequencies. This will quickly show the deficiencies of any amp, and multi-channel receivers with their puny excuses for onboard amplifiers simply do a terrible job with the 7s. The 1077s ability to "track" the impedance curve of a speaker allows it to transfer max power even at surprisingly low impedances. Only "bigger" amps (200 wpc and up) have achieved this sound with my RF7s. The 1077 does appear to sound like a "bigger" amp than my 200 wpc 1080 does, and at least as big as the 250 wpc A21/51.

Soundstage: My initial apparent dissapointment with the amp centered around its seemingly narrow and shallow soundstage. On day 2 I realized that this dummy, in his rush to get the amp up and running had reversed the left and right channels. No wonder everything sounded so weird. I can now report the following. The soundstage of the 1077 in 2 channel mode is at least as wide as the 1080, however, it does lack some of that amps depth. Most of the 1077s soundstage is forward of the speakers so it tends to project instruments out into the room. The musicians seem to be out in the room with you rather than being in front of you on a stage. I was able to moderate this a bit by adjusting the separation width and tow-in of my speakers.

The amp is exceedingly linear. It performs as well at low volumes as it does at high SPL. This has been a characteristic of Rotel amps for as long as Ive owned them, and its a characteristic I enjoy. When I auditioned the Halo A21 for three weeks one of the things that distressed me the most about that amp was the fact that it performed well at high SPL and had a good, if not great top end and a huge soundstage. But it fell apart completely when turned down. The Krell Showcase held up well under similar conditions. It never lost it.

Ive decided that the 1077 is a keeper!

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[nicholtl]

It's good to hear that your quest of a thousand miles has finally come to a satisfying end!

[nuclearay]

Impressive package! Great review.

[SteelerFan]

Congrats on your new amp and I concur with nuclearay, exellent review.[]