About the Rotel RMB-1504
A versatile power amplifier
A versatile power amplifier
Rotel's RMB-1504 delivers 70 watts of clean, robust power per channel to all of its four channels. It's a great choice for driving your overhead speakers in a Dolby Atmos® surround sound setup, or serving as part of a multi-room custom installation.
Convenient connections and switching
There are two pairs of binding posts on the back panel for connecting two pairs of speakers, with switches that allow you to link the inputs or use them independently. A stereo RCA output link lets you daisy-chain an additional amplifier. Three selectable turn-on options (front panel switch, 12-volt trigger control, or signal-sensing) let you further adapt the amp's performance to your needs. Rack mounting ears are included.
Rotel has been crafting high-performance gear for music and home theater enthusiasts since 1961. They focus on creating the best signal path possible, using premium capacitors, transistors, diode bridges, and custom toroidal power supplies to get the most from music and movie soundtracks. Crutchfield is proud to offer a diverse selection of Rotel components including preamps, amplifiers, CD players, and home theater processors.
- 70 watts per channel into 8 ohms (20-20,000 Hz) at 0.03% THD with all channels driven
- 115 watts per channel into 4 ohms
- Class AB design
- custom made toroidal transformer for stable, noise-free performance
- frequency response: 10-100,000 Hz (±1dB)
- signal-to-noise ratio: 115 dB
- thermal and overcurrent protection circuitry
- detachable power cord
- two unbalanced stereo RCA inputs for A/B channel pairs
- independent input level controls on front panel (adjustable via small flat-blade screwdriver)
- mono switch links left and right channels for feeding both with a single mono RCA connection
- link switch sends A channel input signals to the B channels
- unbalanced stereo RCA signal output link
- passes left/right A channel input signals to a connected component
- 5-way binding post terminals for A/B speakers
- 3.5mm 12-volt trigger in/out with signal sensing switch
- rack mounting ears included
Dimensions and warranty:
- 17"W x 5-11/16"H x 17-1/2"D (3U rack spaces)
- weight: 32.8 lbs.
- warranty: 5 years
- Our 60-day money-back guarantee
- MFR # ROT1030005
What's in the box:
- 4-Channel power amplifier
- 6.5' AC power cord
- 40" Mono-minijack cable
- 2 Rack-mount ears
- 2 Pan-head screws
- 4 Counter-sunk screws
- 2 Power button masking rings
- Owner's manual on CD-ROM
- Installation Guide
- Warranty Information
- Rack Frame Assembly Instructions
- Important Safety Instructions
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More details on the Rotel RMB-1504
Features & specs
|Number of Channels||4|
|Power Output per Channel (8 ohms)||70|
|Power Output per Channel (6 ohms)||---|
|Power Output per Channel (4 ohms)||115|
|Bridged Power per Channel||0 watts|
|Parts Warranty||5 Years|
|Labor Warranty||5 Years|
|Inputs & Outputs|
|Number of Inputs||4|
|Removable Power Cord||IEC 3-prong|
|Speaker Connectors||Binding Post|
Robust Class AB 4-Channel Amplifier: The Rotel RMB-1504 Class AB 4-channel amplifier delivers 70 watts per channel into 8 ohms and 115 watts into 4 ohm loads. The use of discrete output devices, a massive power supply with toroidal transformer, premium components, and Rotel's Balanced Design Concept ensures the RMB-1504 delivers superb sound quality. The RMB-1504 is a great amplifier choice for object based overhead speakers in home theater installations and the demanding drive required for custom installation and multiroom audio solutions.
- The RMB-1504's power output is rated at 70 watts per channel with all channels driven. Rotel has chosen to specify the power output in this way because, in Rotel's experience, it gives the truest value of the receiver or amplifier's power capability.
- When comparing specifications for different amplifiers, you should be aware that power output is often specified in other ways, so you may not be comparing "apples-to-apples". For example, the power output may be quoted with only one channel or two channels driven (not all channels), giving a higher maximum figure.
- Be aware that the RMB-1504 is capable of high power levels, in excess of 70 watts respectively per channel. Make sure that your speakers can handle the power of the amplifier. If in doubt about your speakers, ask your Crutchfield advisor.
Balanced Design Concept: Balanced Design Concept is the essential Rotel design philosophy that revolves around three major areas - Parts selection, circuit topology, and critical evaluation. These aspects influence final sound quality significantly and illustrate the holistic Balanced Design Concept approach to Rotel's product development. Thanks to the Balanced Design Concept, Rotel components easily exceed the performance of many mass produced audio products that offer plenty of features but skimp on audio quality, and compare favorably to components that are many times the price. Rotel continues its pursuit of extraordinary audio performance, which elevates the home entertainment experience through their core values of sonic accuracy, reliability, and affordability.
- Parts Selection: Rotel engineers select premium capacitors which provide better performance across both power and frequency spectrums to produce a more accurate and musical reproduction of the audio signal. High quality power supply capacitors provide a more efficient transfer of energy with fast charging and discharge time to ensure the circuits have the reserve power when needed. At each stage of development, Rotel engineers listen to circuit prototypes and revise the design when they feel they can gain a sonic advantage by using a particular component from another manufacturer or by specifying tighter tolerances. Since Rotel is an independent manufacturer, they are free to source parts from highly respected suppliers around the world to fit their requirements.
- Circuit Topology: It’s not enough to simply use good parts. Where you put them is equally if not more important. That's why Rotel keeps their circuit paths as short as possible, so there's less chance that spurious emissions and unwanted leakages will corrupt delicate signal nuances. That's also why Rotel often uses more expensive "on-board" relay source switching, rather than routing a signal from a rear-panel input to a front-panel control. Rotel also relies heavily on something called Symmetrical Signal Trace design. This keeps each channel's signal path identical to the others to preserve the imaging and soundstage. Rotel also uses electrically superior "star" grounding techniques to improve performance because star grounding routes all ground connections to a single point to reduce potential loops that might introduce noise or produce hum. Further, Rotel's Class AB amplifiers don’t use output inductors because they decrease control and, consequently, sound quality.
- Critical Evaluation: Rotel's development team places a lot of importance on critical listening sessions before the final product is sent to market. Rotel electronic and acoustic engineers, both in the UK and Asia, have honed their aural acuity over the course of decades of collective experience to evaluate each stage of product development from working samples, through pre-production and, finally, to verify that final production is the same as the pre-production units. Some sessions evaluate different circuit elements: capacitors, resistors, and active devices such as transistors or operational amplifiers. Others focus on differences in circuit layouts or differences caused by power supply elements. Only after this tuning process is complete with sonic performance confirmed will the product be launched to the market.
Oversized Toroidal Transformer: An oversized factory built toroidal transformer and high efficiency capacitors drive an array of high current output transistors ensuring fast transient timing, accurate detail and controlled consistency of low frequency regardless of the loudspeakers load rating or cable run distance. Maintaining crucial timing and energy while delivering effortless power is a signature trait of a Rotel amplifier providing increased speaker placement options.
Critical Evaluation Of The Circuit Design: Critical evaluation of the circuit design and meticulous selection of each acoustic audio components ensures accuracy, power and efficiency all coupled with an unsurpassed build quality ensuring this amplifier proudly wears the Rotel name.
Unbalanced Analog Inputs: The Rotel RMB-1504 is equipped with two sets of unbalanced single-ended RCA inputs for connection to your AV processor, preamplifier, or receiver. The inputs are labeled "A" and "B". The input signal of the "A" input can be automatically linked to the "B" input, so that a separate input signal cable is not required for that input; allowing you to use all four amplifier channels with the same stereo input signal. The "A" input can also be setup as a mono-channel input with the left channel connected to the right channel of the "A" input.
- Automatic Signal Sensing: Thanks to Automatic Signal Sensing, the amplifier turns on automatically when an audio signal is detected at the RCA inputs. The amplifier will go into standby mode several minutes after an audio signal is no longer present.
- Input Level Adjustment: Two controls on the front-panel, one for each set of inputs ("A" and "B"), provide input level adjustments. These allow you to adjust the gain of the amplifier to match other components in the system.
Line-Level Output: The Rotel RMB-1504 has a set of stereo RCA line-level outputs for passing a unprocessed input signal connected to the "A" channel input on to another audio amplifier or component. The stereo RCA line-level output does not support the amplifier's "B" channel input.
Binding Post Speaker Terminals: The RMB-1504 has two sets of speaker connectors, one for each pair of amplifier channels (labeled "A" and "B") . The amplifier is outfitted with binding post speaker terminals that will accept bare wire (up to 10AWG), pin-connectors, spade-lugs, and banana plugs (single or dual). The power amp will support up to two pair of 4 to 16 ohm loudspeakers. There is no "A" and "B" switch for the "A" and "B" speaker outputs. Both speaker outputs are always active.
- The "A" and "B" input can be setup to send a separate audio signal from a playback source to its receptive "A" and "B" speaker outputs.
- The "A" input can also be linked to the "B" input, so the same source from the "A" input plays through the amplifier's "A" and "B" speaker outputs.
Note: You should exercise caution when driving multiple pairs of speakers in parallel configuration from a single speaker output, because the effective impedance the amplifier sees is cut in half. For example, when driving two pair of 8 ohm speakers from a single output, the amplifier sees a 4 ohm load. When driving multiple speakers in parallel, it is recommended that you select speakers with a nominal impedance of 8 ohms or higher.
12V Trigger In/Out: The Rotel RMB-1504 is outfitted with a 12V Trigger input (3.5mm) and output (3.5mm). These 12V triggers can be used to link other components in your system that also offer 12V triggers, so they turn on and off with one another.
Protection Circuitry: The Rotel RMB-1504 features thermal and over-current protection circuits that protect against potential damage in the event of extreme or faulty operating conditions. Unlike many other designs, these protection circuits are independent of the audio signal and have no impact on sonic performance. Instead, the protection circuits monitors the temperature of the output devices and the current they are handling and shuts down the amplifier if operating conditions exceed safe limits.
Mounting & Placement Options: The Rotel RMB-1504 power amp can be tabletop mounted and also comes with rack-mount ears. The amp takes up 3U rack spaces once the feet are removed.
- The RMB-1504 generates heat as part of its normal operation. The heat sinks and ventilation openings in the amplifier are designed to dissipate this heat. The ventilation slots in the top cover must be open. There should be at least 4" of clearance around the chassis, and reasonable airflow through the installation location, to prevent the amplifier from overheating.
- Make sure that the shelf or cabinet can support the weight of the amplifier. The amplifier should be installed in or on furniture designed specifically for audio components. Such furniture is designed to reduce or suppress vibration which can adversely affect sound quality. Ask your Crutchfield advisor for advice about component furniture.
Notes: The RMB-1504's heatsinks provide adequate cooling for most installations. However, when installing the amplifier in a confined space or near other heat-generating components, additional cooling may be desirable. See Accessories Tab for cooling fan options (sold separately).
Detachable AC Power Cord: The Rotel RMB-1504 comes with a detachable 6.5' AC power cord that plugs into the back of the power amp and into an AC wall outlet or surge protector/line-conditioner (sold separately - see Accessories Tab).