The Box




The answer is The Box

That moment of privacy with your music, your sound system, in your room, in your living room, in your office, in your bedroom. Sound lovers know perfectly that time and those feelings. Want something more; more definition, more solid bass, while adjusted, less aggressive but more precise treble, warm and greater plasticity mids, more present voice, more focused, more real; immerse you deeply in the scene sound. How get this without having to change all the system or a large part of it? How to achieve a substantial improvement with all those
features with a very contained investment?

What is The Box?

The Box is a high quality sound device that has been designed to achieve a substantial improvement in an already existing equipment. Just add The Box to your current setup and start enjoying the rediscovery of your sound system and your recordings without having to replace any component.



What does The Box do with signal? Does it modify it in any way?

The Box is a completely linear amplifier. It’s normal, without making a good scientific and technical approach, to be unaware of the large energy losses involving cable interconnection of sound devices and interaction with other equipments. All audio equipment, in its input, has a series of filters to reject undesired components, for example, interference or direct current. This filter, seen by the source equipment output stage, is a challenge for it of impedance, capacitance in inductance. In addition, combined with the induction of the cable and its capacitance – typically, its impedance is negligible-. The Box, through a careful design of its input and output filters, its topology and the employment of our AE2270 discrete operational amplifier, of advanced audio design, is capable of making your source equipment immune to all this kind of negative interactions. The effect got is as if you could modify your device source physically to get that had an output section of higher quality. Therefore, the result is like buying a device much more level and price that you have currently, but spending much less money, several times less. So simple. So true.

An example of use?

We were doing the following tests with sound enthusiasts:

We had a well known multi-format player(Blu Ray, SACD, CD, etc) from an American brand of around 1,000 euros price point and a high level SACD player from a well-known Japanese brand, widely awarded, 2,200 euros. In comparative tests, obviously, although the multi-format one won in terms of functionality, respecting sound quality, playing SACD and CD, high-level reader won by a landslide. We added a The Box prototype connected to the output of the well known multi-format player and listeners reacted noticing the bulky quality difference between the two devices disappeared, becoming a matter of very subtle nuances and not always in favor of high-level SACD player.

Spending 590 euros they’d have got the same result than spending 2,200 and with the convenience of having a single player and the consequent saving of space, remote controls and complexity. And saving more than 1,600 euros. Is there something better?

How do I setup The Box in my system? 

The Box can be connected between two any sound devices with level line input/output, using a cable with RCA connector. It cannot be easier. You don’t need to replace any component in your audio setup, just add The Box with a RCA stereo cable.

You can connect the box between a Media Player, DAC, CD or Blu-Ray player and a preamplifier or integrated amplifier or between a preamplifier (or DAC with volume controls, often used as preamplifier) and a power amplifier. Or maybe your integrated amplifier has pre outputs and power amp inputs (also known as coupler input/output or adapt input/output) and that is an excellent place to connect The Box.

Even, if you are using an AVR with dedicated power amplifier for frontal channels, you will achieve a huge improvement of quality output given by your AVR to your power amplifier adding The Box between both components.

The Box can also convert your boutique or DIY passive preamplifier or attenuator in a high-end active one.

Can I have more than one The Box in my system?

Of course, you can take benefit from The Box effects by placing one in several parts of the chain of audio.

For example: you can begin placing one between your most used source (let’s imagine a DAC) and your amplifier (or preamplifier). Subsequently, if you have a separate amplifier, setup one The Box between preamplifier and power amplifier. Even if you have an integrated amplifier which has pre-output and power-input terminals, you can add a The Box in that external loop. (Normally, your amplifier will have instructions of how to do that the signal is diverted by that loop.) Then, you can continue incorporating a unit of The Box placed at the exit of each of your other sources.

Multiple The Box connection example.

I have a high-end equipment, will The Box be able to better the result?

Imagine a shinning silver, of magnificent bright appearance, appears gleaming. Someone gives you a product to clean silver and you decide to try it. After using it on your tray, you discover that, actually, it wasn’t as clean as you thought and, now your tray looks even more bright and resplendent. That’s what happens to incorporate The Box into a high-level audio system.

The Box has been subjectively tested with high-end gear like Mark Levinson pre amplifiers and power amplifiers, Marantz high-end range like SC11/SM11 combo, McIntosh power amplifiers, among others. We got reports from customers adding The Box to high-end equipment, like Bryston, with excellent results.

It worths to try it, we are absolutely confident you will love it that we give you have a no-question-asked return period of two weeks.

What about input and output levels?

By default, The Box is manufactured with a 6 dB voltage gain (this means that the value of output voltage will double from the input). This gain is not large enough to present problems with any device that receives its input signal from The Box. Don’t panic, the double of output voltage value does not mean that sounds twice louder and you have problems managing the volume. The gain of 6 dB presents an additional advantage, that is the difference between a balanced and a not balanced (single-ended) signal is just 6 dB, which gives a further application to The Box: compensate the difference of signal level in those systems that use single-ended and balanced signals.

The Box


Nominal gain: 6 dB.
Maximum output level: 14 V RMS or more.
Input impedance: 50 KOhm
Total harmonic distortion:

  • At 1 KHz (20 Hz – 20 KHz BW) and 3 V RMS output: <0,0004 %
  • At 1 KHz (20 Hz – 20 KHz BW) and 0 dBu input: <0,0004 %

Intermodulation distortion (19 KHz – 20 KHz):

  • At 3 V RMS output: <0,0007 %
  • At 0 dBu input: <0,0007 %

Frequency response at 1 V RMS:

  • 20 Hz – 20 KHz: -0,4 dB, +0 dB
  • Channel accuracy < 0,05 dB

Signal to noise ratio: 111 dB or better (at 1 KHz and input shorted).
Stereo crosstalk: < -110 dB (at 1 KHz referred to 6 dBu).
Power consumption: 9 W
Nominal supply voltage: 230 V o 115 V (factory set) 50 – 60 Hz.
Maximum dimensions: 237 mm (L) x 169 mm (W) x 64 mm (H) (including connectors and feet)


What is The Box based on to achieve those results?

  • The excellent QHW Audio’s AE2270 (more information here).
  • Global feedback loop with automatic adjustment depending on the impedance attacked with low output impedance, which provides a great capability in its interaction with any sound device and cable, even those of high length and capacitance.
  • An oversized power supply of very low impedance and low noise.
  • A careful power supply lines decoupling design for low noise result.
  • A ground design with star topology and insulation between signal ground, power ground and safety earth, which provides stability and low noise level.
  • High dynamic range, handling more than 14 VRMS output.

I want to know further: how do you did this?

  • A low vibration, low electromagnetic radiation, high efficiency encapsulated toroidal transformer is used as power supply heart.
  • PCB has been designed with large width tracks and double thickness -70 um instead of standard 35 um- using always the least possible length with the global goal of minimizing impedance.
  • In addition, the advanced PCB design, caring for the relative position of components and functional blocks and, using techniques as “guard rings”.
  • Symmetrical design, to make the influence of current induced by power supply and mains magnetic fields – unavoidable physical fact – the closest possible on both channels, thus maintaining the best stereo imaging.
  • Carefully selected components: low impedance power supply filter capacitors, metal film resistors of 1% of tolerance in audio signal path. Polypropylene film capacitors where possible and polyester film where values doesn’t allow the previous. With the
    guarantee of the best brands: Nichicon, Panansonic, Elna, Vishay, Wima Epcos, etc.
  • A chassis of extruded aluminium which gives thermal stability to the set, because the whole enclosure can act as a heatsink to air, and mechanic, because the reduced parts count gives it great rigidity, avoiding microphonic effects.
  • Of course, The Box complies with RoHS directive.

In addition, The box is hand-crafted in Spain


The Box Owner’s manual in PDF

The Box product brochure in PDF



On Off Magazine – Spain – No 316 – October 2019. Josep Amengol.

“Result is this ‘magic box’ changes sound for the better when we use it between source and amplifier. After adjusting volume (it goes up 6 dB due to employed buffer) sounds gain deepness, precision, and, specially dynamics: more realism. Effect is better than many esoteric cables and for less money, since The Box precisely avoids or minimizes cable effects in connection.”

See complete review at On Off site (in Spanish).

TNT – Audio NZ – March 2018. Richard Varey.

“In conclusion, whatever it is doing, it sure makes my music playback sound marvelous. It takes my daily music experience to the level of magnificent. If you want an easy, unpretentious, highly effective enhancement to your music listening pleasure, then this is a system upgrade for you. And at this price, a most excellent deal it is, too.” Read complete review at TNT – Audio site.


There are no reviews yet.

Only logged in customers who have purchased this product may leave a review.