By Maxim Lyadov
Our readers know VideoLogic company (www.videologic.com) as a manufacturer of quite expensive computer acoustic systems for a home theater, the DigiTheatre series (see VideoLogic DigiTheatre and DigiTheatre DTS article) and the Santa Cruz sound card (Santa Cruz from Voyetra Turtle Beach). The company, however, has another interesting series under the Sirocco name.
For deeper details I recommend to go to the manufacturer site, but for your convenience I have charted a summary table:
The whole VideoLogic acoustic system is based on quite decent Audax speakers (by the way, the company is a part of Harman International concern). All the acoustic systems have magnetic screening what allows to place them near the PC monitor. The cases of all ASs are produced according to the modern technology: of MDF laminated with plastic.
Today we will concern the top model of this series - the Sirocco Pro active studio monitors.
The VideoLogic Sirocco Pro set includes:
Note that there are no any protective gauzes on the speakers. It implies that the equipment belongs to professional studio level.
Take a gander at its dimensions:
The cables and professional connectors XLR are of high quality. The commutational connectors are made very competently, the female connector fits very tightly. The signal comes to the HF and MF/LF satellite heads via the bi-wiring what means separation of the HF and MF/LF channels in the amplifier (bi-amping). It delivers from designing filters inside the acoustic system and doesn't cause a fall of middle and high frequencies in volume peaks of basses while playing the music.
On the rear panel of the amplifying unit you can find the following connectors:
The digital inputs switch is unfortunately located on the rear panel what is not very convenient if you change the signal source quite often.
The Sirocco Pro's front panel is rather conservative:
The biggest regulator is the master volume control (volume). Then comes a separate subwoofer level regulator (sub). For frequency correction they have installed a dual filter called tilt which raises high frequencies and reduces the low ones at the same time (in ±6 dB range). The input selector, source, allows choosing a signal. There is also a headphones standard 1/4" jack that switches off the acoustic system automatically. The small button called monitor serves for disabling the subwoofer with a separation filter, and for applying full-frequency signal to monitors, for more precise control of positioning of stereo images on the panorama.
The amplifying unit also contains a DA converter with its interfaces. According to the specification, the Sirocco Pro is equipped with the DAC 24 bit 96 KHz, with support for input digital signals of 32/44.1/48/96 KHz, and 16/18/20/24 bits.
The User's manual contains also spectrogram printouts obtained when measuring DAC parameters (I wish there were characteristics for the whole audio track):
Frequency range (20 - 20 000 Hz, 0.5 dB deviation)
DAC input/output linearity (ideally straight line)
Crosswalk (15 dB rise in the HF spectrum)
1 KHz test sinusoid (quite low level of the odd harmonics and absence of the first even ones)
Distortions and noise vs the signal level
Now let's turn to what hides inside this combined amplifier/DAC:
The toroidal transformer is quite big. Now let's check whether the total capacity of the rectifier capacitors in the power supply unit corresponds to the specified one by the manufacturer. Everything is right, 6800 mF * 6 = 40 800 mF, what is a bit higher than the specified 40 000. Two big power supply stabilizers which are located near it are equipped with heatsinks what also provides good feeding.
There is no a DSP on the printed boards, the tone control, which is analog in nature, is assembled with descrete components. The amplifying part is based on four big amplifying chips (or microassemblies): 2 for the satellites and two-stage amplifying for the subwoofer. Unfortunately, it was difficult to check the marking since everything was stained with thermal glue and covered with big black heatsinks (the rectangles in the center of the photo).
The layout is competent and accurate: the chips of the receivers and the DAC are located on the separate printed board, and power and signal tracks are near 5 mm wide. There are only two disadvantages: lack of the safety device in the power supply unit and too long non-screened signal cables from the digital board, even though they are rather solid, with large section.
Now up the board with digital interfaces and the DAC:
There is nothing surprising. The signal proceeds from the input digital connectors to the universal all-format digital receiver from Crystal, CS8414, and then goes to the DAC. In this model they use XWM8733 converter chip from Wolfson with 24 bit digit capacity and 96 KHz sampling rate (14-pin chip in the center of the photo). Some budget sound cards are equipped with AC'97 codecs from this manufacturer which have nothing to do with this 24/96 DAC in characteristics. By the way, Wolfson Microelectronics was chosen a supplier of analog components and AC'97 codec for the future Microsoft's Xbox console, according to Yahoo!.
Note that all sound cards I have with different digital interfaces (optical Toslink, RCA S/PDIF), as well as from the internal connectors of the SB Live! and ABIT AU10 sound cards with the nonstandard 5 V signal amplitude worked flawlessly with the Sirocco Pro in digital mode. Analog inputs also have sensitivity reserve (around 400 mV) with reference to a standard linear level what simplifies integration with other audio equipment.
Now we can turn to examination of acoustic systems. The Sirocco Pro includes wooden (MDF) speakers hermetically sealed with rough plastic. All parts fit perfectly each other.
The subwoofer's design is quite successful: the phase inverter is located in the lower part of the front panel, and the dynamic head rationally rises above the floor. Low frequencies are not mashed due to reflection from the floor (what is not so important for the home theater, but it is for music).
As I have already said, all Sirocco Pro acoustic systems have dynamic heads from Audax. The satellites are equipped with a MF/LF radiating cone 5.25" in diameter based on the proprietary HDA (High Definition Aerogel) technology. High frequency fabric twitter 25 mm in diameter with usage of neodymium magnets. The subwoofer includes an 8" conic HDA radiator. The subwoofer is also magnetically isolated what allows placing it near the system unit of the computer. The satellites' power in RMS at 1% THD amounts 2 to 25 W, and 50 W for the subwoofer. The maximum sound pressure level (SPL) constitutes 110 dB. The amplifier has 10 Hz - 100 KHz amplified frequency band. At the rated volume they guarantee not more than 0.01% THD at 1 KHz.
I should note that the Sirocco Pro volume at the half amplifying level with the standard input signal was enough for working in home studio. And at 2/3 level you it may suit for rather large room with background noise level equal to 50 dB.
The worst drawback of the system is its price (DAC + amplifier + 2.1acoustics = $900). The manufacturer positions this model mainly for Hi-Fi and pro audio application. According to them, it perfectly suits home studios, video editing and post-production, hi-fi, corporate presentation systems, PC audio playback and even games.
In the first turn, I want to note accuracy of sounding. Secondly, the phase precision is excellent. Due to the fact that amplifying and acoustic parts go in one "box" the manufacturer had an opportunity to reach the max matching according to all electro-acoustic parameters. The subwoofer is well coordinated with satellites both in middle and high frequencies.
And thirdly, I have nothing to complain about in FS. I heard no falls in either frequency band. And as for the tone control, I didn't like it at all. It seems to serve for some kind of complicated frequency correction in case of frequency distortions because of the specific acoustic properties of the room or something like that.
Besides, I should note that audio reproduction is the standard at which everybody should be aimed. I mean that it's the minimum when it's worth speaking about the sounding quality. During those two weeks of testing I tried to use the Sirocco Pro in my home studio. So, I have only positive impression.
Of course, you can use this set for games and audio playback. When playing audio compositions the sounding is very even.
Highs of the VideoLogic Sirocco Pro:
Lows of the VideoLogic Sirocco Pro:
Write a comment below. No registration needed!