quelle différence avec la 1402 vlz pro ???

the XDR mic preamp stages have been enhanced to a new second generation form called XDR2. An important improvement in the new XDR2 preamp is a significantly extended frequency response, but not at the high end: the vital change is in the low frequency (LF) extension. In my experience, LF headroom and extension is what differentiates an average mic pre from a great one, and it also helps to avoid heavy phase shifts building up as the signal passes through other circuit stages.

There is also more headroom in the new preamp design too, accommodating signals to +22dBu without coloration, and with a claimed 130dB dynamic range. The distortion figures are also much improved, with total harmonic distortion falling to a superb 0.0007 percent. RFI rejection also remains a cornerstone of the input design — important when the circuitry has such a wide bandwidth — and the input impedance has been raised from 1.3 to 2.5kHz, which will benefit users of dynamic microphones with more high end and less coloration.

The other major change to the console is in the mix bus, with a revised topology that keeps the signal level depressed through the mix amps and bus faders, before making up the gain in a post-fade buffer. This provides greater headroom, making it easier to mix lots of hot signals with less distortion. Indeed, the overall console THD figure has been halved in comparison with the previous design, to just 0.0025 percent — and that can be heard in terms of less coloration, especially when driving the desk hard.

Strangely, though, the crosstalk figures appear to have worsened slightly in the new console, up 2dB from -84dBu in the previous console to -82dBu in the new VLZ3. Similarly, the main mix noise with all faders at unity is also a little worse, up 4dB from -90 to -86. In practice, though, I doubt whether anyone would be able to tell the difference, and with the greater headroom and lower distortion offered it is now easier to drive the desk harder than before anyway, permitting a greater dynamic range.

Impressions
I have long been a fan of the original VLZ Pro consoles and their XDR preamps, which have always been amongst the best of any budget console and, for that matter, nipping at the heels of many high-end consoles. Indeed, I regularly use a little 1402 VLZ Pro mixer for recording 'serious music', with excellent results.

The new design seems to have retained the sonic neutrality of the original (as opposed to the definite 'sonic flavour' introduced with Mackie's Onyx preamp design), but it is noticeably cleaner and less strained when handling hot signals. Noise levels seem much the same, but the bottom end sounds fuller and more natural.

Mix bus headroom was always a weak point in the original designs, but there has been a significant step forward with the VLZ3. Previously, I was wary of allowing signals to reach +7dBu on the console meters, as the sound quickly became strained above this, but when using the 1642 VLZ3 desk I found it remained clean and unstrained even with the +10dBu LEDs on all the time — which is a vast improvement.

The other important change is to the stereo channel EQ. Reducing the centre frequency of the low-mid band has made it much easier to apply tonal correction that works musically. It's surprising just how significant that change is in practice.