Hello,
just recently I had a very interesting experience regarding the RAAL REQUISITE SR1a which I would like to share with you. Please forgive my not so perfect English, but I am not a native speaker.
Some time ago I made an extensive review of the SR1a on Musicalhead for you. Although the RIVIERA AIC10 undoubtedly offered outstanding musical qualities, I already suspected at the time that under certain circumstances only much more powerful representatives of the amplification guild would be able to make full use of the RAAL in terms of performance.
As a rule, my preferred monitoring volume is in the range of 80 dBA. However, I can easily imagine that some of the Knights of the Grail may also prefer higher listening levels for the fine tones. For this reason, I have been on a new quest for the Grail for some time now, in order to find an optimal playing partner who can drive the SR1a without problems even at 100+ dBA.
And in my listening test I am taking the V110 SE valve integrated amplifier from the German high-end manufacturer OCTAVE under the musical magnifying glass for the first time. At least in its function as a veritable headphone amplifier. OCTAVE has been building tube amplifiers for over 30 years, which, according to the manufacturer, are now just as stable and reliable as corresponding transistor amplifiers.
The various models made by the tube manufacturer from Baden owe their longevity to intelligent control electronics - sophisticated protective circuits guarantee unsurpassed long operating times. And all OCTAVE tube amplifiers are based on high-quality components - from the input sockets to the output transformers, which are developed almost entirely in-house and are carefully handcrafted on site in Karlsbad.
The possibility of regular equipment upgrades also guarantees high value retention and, according to the developer and company founder Andreas Hofmann, guarantees the owners the highest level of music enjoyment using state-of-the-art technology for many years.
In the long run only power rules
The V110 SE is the second largest integrated amplifier in OCTAVE AUDIO's product range after the V80 SE. The Tube-Beau has an enormous output power of 2 x 110 watts into 4 ohms, as 4 KT120 power tubes are used in the power amp section. In combination with a specialised power supply unit and novel output transformers, the peak output power is almost doubled compared to conventional push-pull power amplifiers. The driver stage, which drives and controls the end tubes, thus comes a big step closer to the ideal of the push-pull principle.
The often criticised push-pull principle also does its job without any influence on the sound. As a result the V110 SE convinces with a high linearity and stability, which should make IMO the perfect partner for the RAAL REQUISITE SR1a. But why didn't I choose OCTAVE's top model, the V80 SE, for this listening check right away? Quite simply - the new V110 has a further equipment feature which is probably unique in the tube world at the moment.
Thanks to the innovative circuit and an enormous bandwidth of usable feedback, the electrical damping factor can be adjusted to the Serbian ear loudspeaker in 3 stages. By the easiest change of the corresponding input tubes (ECC82/Low, ECC81/Mid, ECC83/High) a very sensitive adjustment to the electrical load is achieved. The medium version (damping factor 7.2) is already used ex works. It is recommended for playing partners (primarily loudspeakers, of course) with a strongly rising impedance curve in the mid-range. The high version (DF 10), on the other hand, is primarily intended for potential partners, who usually use low impedance in the mid and high frequencies.
Finally, the ECC82 driver tube for the lowest attenuation factor (5) represents the most sensible option if the transformed candidate tends to be rather harsh due to overly tight diaphragm control. Since the conceptually integrated resistor network of the SR1a is hardly subject to fluctuations in load impedance and is therefore at a nearly constant 6 ohms, I prefer the latter variant for my listening check, even on a purely emotional level.
With its output power of 2 x 110 watts into 4 ohms, the OCTAVE V110 SE also meets the performance requirements of the Serbian manufacturer fairly accurately. And the German tube amplifier does not show any nakedness whatsoever on the SR1a in the following sound test. My listening test is played back using my tried and tested AURALIC set, consisting of ARIES G1 and VEGA G1, which are connected to each other via USB using a TELLURIUM Q ULTRA SILVER digital cable.
A handmade DOLPHIN BLACK GOLD chinch cable provides the adequate supply line to the OCTAVE tube amplifier. Incidentally, products from the American cable manufacturer SHUNYATA RESEARCH serve as first-class power supply lines. For the tonal assessment of my new test candidate, the usual suspects are of course once again used - listening examples from the fields of rock, pop, blues, jazz and classical music, which I am very familiar with, saved as high-res files on the corresponding hard disk.
Perfect playing partner for the RAAL
After a few nightly listening sessions I decided, as expected, in favour of the ECC82 preamp tube, as the V110 SE with the lowest possible electrical damping in combination with the SR1a is in my opinion the most harmonic. Especially in terms of (fine) dynamics the RAAL REQUISITE SR1a in combination with the V110 SE IMO sets new standards in the headphone segment. The extremely confident OCTAVE integrated amplifier truly drives the Serbian ear loudspeaker to maximum performance.
Due to the exorbitant speed of the full-range ribbon-equipped ear loudspeaker, volume and speed changes are so lightning-fast that sometimes I actually feel like I'm in the corresponding live event. Unbelievable. No headphone I know of is currently able to follow complex musical signals with such immediate impulse fidelity. Of course, this is basically no different with a RIVIERA AIC10, but at somewhat more moderate volume settings, which I usually maintain.
At monitoring volumes >85 dBA, on the other hand, coarse dynamic jumps with the RIVIERA appear slightly limited in direct comparison to the OCTAVE. In particular, bass impulses are given considerably more pressure and precision by the German tube amp. The reproduction in the low bass range also appears more confident overall if higher levels are preferably used.
And although the SR1a in combination with the V110 SE does not quite reach the low frequency volume of a HIFIMAN SUSVARA or ABYSS AB1266 PHI TC, the bass reproduction of the RAAL offers highly audiophile qualities. Especially the transient response is perfect despite the relatively low electrical damping of the OCTAVE. In the mid-range, the tube-reinforced integrated amplifier is convincing with its extraordinarily natural sound colours, regardless of the Russian KT120 TUNG SOL tubes used. Voices and instruments are placed in the musical context in an airy and, as it were, sharply altered manner, without lacking sufficient substance in the basic tone.
Even though the RIVIERA AIC10 gives it a little more plasticity and is also slightly more spacious, the V110 SE nevertheless plays at the highest level in the sound-sensitive midrange. Due to the low damping factor, however, the high notes are also reproduced without undue harshness, although the V110 SE cannot quite match the phenomenally silky high frequency reproduction of the RIVIERA AIC10.
Nevertheless, the sibilant reproduction via the German tube amp is quite relaxed - good source material is a must. And the OCTAVE V110 SE, in combination with the RAAL REQUISITE SR1a, also impresses with absolutely impeccable detail work, a fantastic resolution and very realistic reverb vanes. Once again a world class performance of this truly excellent playing partner pairing.
Unfortunately, the inclined Grail knight of fine tones has to dig deep into his pockets for this extraordinary tonal performance. As expected, the OCTAVE Pretiose is not available at a bargain price. 6.999,- Euro will be sold by the dealer of confidence in Germany if you want to use your RAAL headphones with a V110 SE tube amplifier in the future. Nevertheless, I explicitly recommend every owner of an SR1a to subject the OCTAVE V110 SE to an extensive acoustic inspection if a new acquisition is planned - and the estimated budget allows it.
Yours Fidelio