QHW Audio The Box II analogue sound signal improver

Hi-Fi equipment sound quality analogue booster
The Box II dramatically improves the sound quality of any existing Hi-Fi equipment without having to replace any component. Just add The Box II into the audio path.
Connect it between any two line-level components and start enjoying the upgrade. Between your favorite source and your amplifier or your preamplifier and power amplifier or -why not?- two units in both places. 
Also, if you are using an AVR setup with dedicated power amplifier to drive frontals, you can set up The Box II at your AVR line output, dramatically improving your AVR output quality. Or you can use your integrated amplifier pre-out power-in loop, if existing or even a tape monitor loop as used to be in old amplifiers to incorporate The Box II into your existing equipment.
In addition, The Box II provides five levels of selectable gain, giving both more functionality and suitability. You can choose between no gain, +3 dB, +6 dB, +9.5 dB or + 12 dB.
This gives you not only better adjustment to your tastes or equipment, but more functionality. In example, you can use The Box II to add an active stage to a passive preamplifier or to an IC based volumen control, building this way your own exclusive configuration of a high-end preamplifier. Or to better the combination of a low output preamplifier with a low sensitivity preamplifier.
You can also use The Box II to compensate level difference between components which can allow you to combine a relatively low output level preamplifier with a relatively low input sensitivity power amplifier or a relatively low output level source with a low input sensitivity preamplifier or integrated amplifier. 
The Box II: the evolution of The Box
The Box II -like former The Box- is based on our famed AE2270 discrete operational amplifier. A notable improvement over its predecessor is done in feedback topology, which now incorporates a DC servo, giving us the chance to omit two big capacitors in signal path, improving low end response and transparency.
The Box II uses 70 μm thick copper in its PCB -instead of 35 μm standard- and has been designed SMT technology when possible, providing the shortest path possible to signal. Thin film resistors 1% tolerance or better have been used thoroughly signal path among NP0/C0G capacitors due to its pretty flat capacitance in the whole audible band. 
The Box II, as opposite to former The Box, employs an external power supply, which allows you to keep the supply far from sensitive small signal circuits and also helps to make the device more than two times smaller and lighter than its predecessor, which makes it easier to place in your current setup furniture. The Box II also has lower power consumption.
 

The Box II is designed, soldered and assembled by hand in Spain.
Technical specifications
Input impedance: 50 KOhm
Output impedance: 10 Ohm
Maximum output level: 9.5 V RMS
Residual noise: < 1 uV RMS (input terminated with 47 R)
Signal to noise ratio (referred to 1 V RMS):  126 dB or better 
EIN: < -123 dBu (input terminated with 47 R, +6 dB gain)
Total Harmonic Distortion at 1 KHz, 20 Hz – 20 KHz passband: < 0.0006 % (at any gain, up to 4 V RMS of output on 10 KOhm load)
Intermodulation Distortion (19 KHz, 20 KHz): < 0.0006 % (same conditions as THD)
Frequency response: 20 Hz – 20 KHz better than ±0.1 dB
Power supply: output 36 V DC 1A, input 100 – 240 V AC 50 – 60 Hz
Dimensions (L x W x H): 155 x 109 x 45 mm

The Box II comes with two years of warranty against manufacturing faults.

Shipment will be done through DHL Express. Transit time is approximately 48 hours.

Please, note that since this is an almost artisan product it is produced unit by unit at our facilities in Madrid, therefore, sometimes it can take up to a week to be ready to ship.