RMB-1095 Build Quality

My wife and I like to occasionally go out and treat ourselves to a nice dinner. On these nights the baby gets sitted and the checkbook opens up for some special culinary delights. Home theater enthusiasts like to splurge too, and when it's time to spice up a mid-priced receiver or processor, Rotel is here to offer an affordable upgrade - one that will definitely improve the amplification stage of your system.

Rotel's 5-channel RMB-1095 is THX Ultra certified and boasts 200 watts into 8-ohms (20Hz-20kHz) with all channels driven. It can drive any speakers rated at 4-ohms or greater and has 116 dBA SNR (more on this later). Weighing in at 75lbs and standing over 9" tall there are no smoke and mirrors to be found here.

Inside the Box

Open up the RMB-1095 amp and you'll be greeted with a densely-packed assembly of solid state technology. The first thing that should catch your eye is a large 1.2kVA toroidal transformer. What you may not see is its twin, an identical transformer situated directly below it. Filling out the rest of the power supply are eight 80V 15,000 uF capacitors. You won't be able to get a good look at them due to their location within the enclosure, so take my word on it. These are what are now known as slit foil capacitors, named for the tiny slits that are cut into the aluminum strips of the cap. The Rotel also employs thirty 150 watt, 15 amp Toshiba bipolar transistors as output devices. 15 are configured as PNP and 15 as NPN making a push-pull class AB amplifier design.

Editorial Note
Rotel sports some very cool features and design practices with this monster amplifier including:

• Six high current complementary output power BJT's per channel - paralleling multiple BJT's is a good method of ensuring amplifier output impedance is low enough to deliver high current while driving low impedance loads
• Multiple high voltage capacitors ( 8 x 15,000uF = 120,000uF total!) In order to do 200wpc a minimum recommended cap voltage of sqrt(2)*40 + 5 = 63V should be used. Using 80V gives them plenty of design margin and added headroom. Using multiple smaller sized caps like Rotel employed ensures low ESR caps for minimizing power supply ripple and achieving a stable and clean power source.
• Dual 1.2kVA transformers ensures this amp can utilize the full rated power from the wall outlet (120V,20A) if called upon.
• Excellent SNR spec of 116dBA (full power) which translates to about 116 - 20*log(40/2.82) = 93dBA at one watt. It's important to have a low noise floor at low power levels where the amp spends most of its time. In this regard, the Rotel did not disappoint both on paper or during real world listening tests.

I believe the interior to be well laid out, with heatsinks arranged around 3/4 of the chassis' circumference. The heatsinks are visible on the front of the unit only, giving it a "we mean business" sort of look. Some prefer their heat dissipation to be hidden on the sides, however I think Rotel's design adds to overall look of the unit, especially when offsetting an aluminum center console (also available in black.)

The center console highlights the included thermal protection circuitry which protects the amp in case of faulty operating conditions. There is also independent Left, Center and Right channel protection which engages when load impedances drop below 2-ohms, such as when a speaker wire is shorted, the unit overheats, or a highly reactive or extremely low impedance speaker load is encountered. Activation is indicated by LEDs above the power switch. This circuitry automatically resets after a cool-down period.

The power switch is a convenient pushbutton that matches the center column, which is available in aluminum or black. It has a nice snap to it that leaves the impression of a well-made component.

Rear Panel & Connections

Taking a look at the rear of the Rotel RMB-1095 will show off the high-quality WBT 5-way binding posts. These are the premium kind, and really do a lot to dress up the rear of the amplifier. In addition, should you choose to utilize bare speaker wire, the holes in each of the speaker connector shafts are situated so that all cables will be vertically-oriented - a nice touch, resulting in a cleaner cable assembly.

The RMB-1095 allows for both balanced XLR and unbalanced RCA input signals, so if you have a high-end processor with balanced XLR outputs you can maximize your potential. One additional input option is the DB25 connector which is essentially a neater way to integrate five unbalanced channels. Primarily used in custom installations, this connection must be used in conjunction with five open-circuit RCA plugs which ensure proper impedance.

A 3.5mm 12V trigger connection for the amplifier is provided. It accepts anything from 3-30 V and must be engaged via an on/off switch. There is also a 12V trigger output jack for daisy chaining the 12V signal to other components. To use the 12V trigger, the amp must be on. Disengaging the front power button turns off all power to the amplifier regardless of trigger inputs.