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Rotel RA-04 SE AmplifierTokyo based manufacturer Rotel was founded by the Tachikawa family in 1961, and over the last fifty years have built a reputation for making audio equipment which seems to offer just a little bit more than most of the competition. Although most manufacturing now takes place in a company owned facility in China, the family still control operations from the Japanese head office. Robert Burn, Product Development Manager for Rotel Europe, advised me that development of some models takes place in the UK, and it was here that the RA-04 model, introduced in April 2006, evolved into the RA-04 SE which we are considering in this review.
Introduced in October 2009, this conventionally styled unit uses the same 435x72x342mm (w x h x d) pressed steel casework as its predecessor, which is available in either silver or black. The front houses, starting from the left, the power button, topped by two blue LEDs. One indicates that power is present, the other lights up during switch on, but should otherwise remain unlit, unless the onboard thermal and over-current protection circuits come into play. Beside these are two 3.5mm mini jacks for the headphones output and Media Player input (selected by turning the source knob to AUX 2). After this are three small knobs for speaker selection and treble and bass adjustment. Beside this is a small button which bypasses this circuitry entirely. Controls for volume, balance, tape monitor and the four line level inputs plus an inbuilt phono stage complete the picture.
The back is equally well populated with gold plated RCA phono sockets for all inputs, and the tape loop. Pre-Out sockets allow for bi-amping with a suitable power amplifier. Two sets of speaker sockets are provided, Speakers A being connected directly to the output stage of the power amplifier, whilst the B outputs are fed via inductors to allow the use of longer cables to power speakers in another room. If you bi-wire, as I did throughout this review, then the bass unit connection should be made here. An IEC mains input socket is fitted on the far right.
Despite its slim build the RA-04 SE weighs 5.9kg. Some of this is accounted for by the Rotel designed and manufactured 180 VA toroidal transformer. This is fed from a full wave rectifier (8A, 400V) circuit. Alongside the transformer are banks of Rubycon USR 6800 microfarad reservoir capacitors. A pair of transistors configured as series regulators provide the positive and negative feeds to the line stages, which use OPA 2604AP op-amps, and to the NE 5532 AP dual opamp in the moving magnet phono stage. Should the tone controls be in circuit, they provide a claimed 4 to 6dB of boost or cut, centred around 100Hz and 10kHz respectively, via a NJM 2114 D op-amp.
The power amplifier is a traditional complimentary stage using matched 2SD1047 and 2SB817 bipolar transistors. These are 140v, 12A devices which are physically positioned near to the power supply. Other components, such as resistors and capacitors are made by companies such as Rubycon, Panasonic and Welwyn. All of this is mounted on a PCB which features input signal tracks interleaved with grounded tracks to minimise crosstalk. Copper 'bus-bars' are used to convey high current around the circuit, which also features star earthing.
I started my listening with the Rotel driving my Chario Ursa Majors, using both the Clearaudio Master Solution (with the Benz Micro Wood SL MC cartridge feeding through the Leema Agena phono stage) and Leema Acoustics Antilla CD player as sources. Being in the front room, it also found itself on A/V duties being fed by the digibox. In this environment the lack of a remote control proved slightly inconvenient, but the sound quality made up for it. I was impressed with the amount of background detail that came through; outdoor environments were portrayed with a sense of space around the main voices that was convincing, while studio spaces seemed accurately described, with the picture on the screen relating to the size of the space being portrayed in the sound.
Moving on to music, I started off with Verdi's opera, 'Il Trovatore', with one of my favourite pairings of Renata Tibaldi and Mario Del Monaco taking the leads, I was very impressed with the quite gutsy way this budget amplifier acquitted itself with fairly demanding music through a pair of speakers that are not the world's easiest to drive. Although they measure 91dB sensitivity, they are a nominal 4 Ohm load, and the twin 170mm subwoofers in each of the lower cabinets tend to soak up power when the volume is turned up a bit. This can result in some amps getting a little flustered and losing what grip they did have over the lower notes.
In this case the Rotel behaved very well. The clang and crash of the 'Anvil Chorus' was played without trouble at quite high volumes, while maintaining its musical integrity. Admittedly it wasn't the deepest or most seismic bass that I have heard, but I can think of very few amplifiers at this price that would have played this music with that amount of finesse. The 'Miserere' in Act 4 sounded lovely. The feeling of distance between 'Leonora' outside the tower, and Manrico's voice, coming from the prison inside, had their differing acoustics laid out for inspection. I could close my eyes and almost picture the scene. More importantly, the harmonies created by the two voices entwined around themselves, helping create the emotional intensity of two lovers saying their last farewells.
A couple of days later the Rotel was moved upstairs to power the somewhat easier load of the Kelly KT3s. Measuring 6 Ohm impedance and 95dB efficiency these speakers are less demanding to drive from the power point of view. With the Sondek in charge running both the MusicMaker Mk lll and the Origin Live Aladdin Moving Iron cartridges through the onboard phono stage, I was again impressed at the level of detail that this £300 amplifier was capable of putting out. I liked the fact it didn't try to overplay things with unnaturally big bass or over emphasised treble, but kept a grip on both the frequency extremes, and made coherent sense of the midrange.
Playing a 1958 Mercury pressing of the 'The Flying Platters' I found myself immersed in the sounds of late fifties Doo-Wop. One of my favourite tracks on this record is 'Mean to Me' which features Zola Taylor on lead vocals, with the men providing backing harmonies and the occasional "wah wah", supported by a easy flowing orchestral background, rooted very much in the swing tradition. Although this record is in pretty good condition, it has a couple of marks here and there, and there were a few occasions where I was missing the stereo/mono switch which would have reduced these sonic distractions to a virtually unnoticeable level. Despite this, the music flowed in a foot-tapping manner which ended up with me playing the whole LP through, instead of just 'cherry-picking' a few tracks as I normally would when doing the 'serious' listening part of a review.
I was impressed with the way the phono stage handled such an elderly record. Older recordings, when played through cheaper phono stages and amps can very often sound a bit thin and ethereal, but this amp belied that, producing a sound that was solid and focused.
Moving a little more up to date, and into stereo again, I played Peter, Paul and Mary's eponymously named 1962 first LP on the Warner Brothers label. The men's voices were placed directly in front of each speaker, with Mary in the centre. Again the sound was focused and engaging, ballads having a thoughtful air about them and the more up tempo tracks displaying the energy and drive that made this group one of the most popular folk acts of the sixties. The guitars had a natural and shapely sound, with just the right amount of twang to be believable, although I have heard greater definition to the picking through, admittedly, more expensive amplifiers.
The group's version of Pete Seeger's 'Where Have All The Flowers Gone' showed this; the combination of strummed and plucked notes emanating from the left and right sides seemed to balance and correspond with each other, and provide just the right level of backing to Paul Stookey's lead vocals.
By comparison the top ten hit 'If I Had A Hammer' displayed passion and intensity - they sounded as though they really believed in what they were singing and the message they were trying to put across as part of the American civil rights and anti-war protest movement.
Coming right up to date I had a go at blowing the cobwebs out of the Kelly's bass ports with the Phony Orphants album 'It Cetera' on CD. This is pretty full on psychedelic trance, complete with pounding bass and strange noises swooping across the soundstage. Despite only having a claimed 40W per channel on tap, there seemed no lack of power to keep the drums and bass rolling at high volumes, and it was only when I really pushed the volume control round that I felt that the sound was beginning to lose cohesiveness (this was so loud I only did it for a few minutes in deference to my hearing and neighbourly relations!).
At the start of this article I said that Rotel always seemed to offer just that little bit more, and this amplifier is a perfect example of that. It seemed to have power capabilities beyond those specified on paper, and to put it across in a credible manner. Imaging and detail were very good, and it proved content to replay whatever was fed through it in an even handed manner. Practical drawbacks such as a lack of remote control and mono switchability were offset by the comprehensive nature of the sound. In my opinion it punches above its price by a noticeable margin, and as such, offers good performance at a very reasonable cost. It is a thoroughly thought out, and well developed design that will win many friends. ![]() |