Info for Sportis: There is a potentiometer on the volume control.
With respect to technology ... I'm not an Engineer (I am but not an electronics one) so I'd conclude by saying this is an innovative development of some existing technologies with some in-house new ones added on, created by an in-house R&D team, lead by a remarkable man with a small, (for now) family run UK manufacturing business ... just the sort of company, I like. I read a fantastic article on BBC about micro-companies that are challenging, with technological developments and micro-manufacturing, corporations with huge Human resource. Gives me hope!
That aside, what I am really looking forward to is letting you all hear Maestro and see/feel it (tiny, the size of my hand, beautiful chassis milled from solid aluminium - see CAD below) so formally welcome you to P&S, Linnegatan 5, Göteborg next Tuesday evening. Please ring/mail me if this would be of interest or alternate dates if this does not suit. 5 or more and we do the event. Those in retailing of music instruments & studio equipment will be formally invited at a later date to a special event .... this is an awesome little neutral, and insanely clean sounding tool to use for home or studio, mixing and mastering, to challenge allot of expensive studios ... when used with pro-tools, a macbook and some LINN speakers.
Some possible tests for Tuesday: As we have allot of rooms is should go very quickly - Send music/film Wireless from Spotify (320 kbs) & Youtube then wirelessly from a Nas on the network CD & 24 Bit. Move then to direct coupling with Macbook then AVA Zara Premium, both with locally stored music on their hard drives. We can set up separate rooms with Majik 109, Unik, 140's and 212 to see how far we can take it.
Hope this helps ... some info direct from AVA
''It can all get a little too technical, but for those who 'really need to know', we've put together a brief description below. There are 3 core stages that the incoming digital stream is processed through - and it's not until the final stage that it becomes 'analog' - and it's this feature amongst others that keeps the music 'true'.
Modulator
The technology used in the Maestro-50 is based on a pulse-code-modulated (PCM) to pulse-width-modulated (PWM) converter called a modulator.
The modulator receives the audio in PCM (I2S) 16-24-bit audio format with a sample rate depending on the input. In a PCM signal format each sample has a assigned amplitude, see below (left side). PWM format signal (right side) has the magnitude for each sample described as a width as oppose to a height in PCM signal. The signal is up-sampled eight times internally (e.g. 8 x 48kHz = 384kHz) and then the modulator converts the signal to PWM with 384kHz switching frequency.
The sample rate is 44.1kHz. The amplifier selects automatically the sample rate and can run with up to 96kHz. No up or re-sampling is used.
**I played Craol Kidd 192 Htz on it just 5 minutes ago - Martin**
To compare, a CD-player uses 44.1kHz and DVD-player 48kHz. CD/DVD players that specify higher sample rates are using up-sampling. The amplifier accepts digital audio input with a maximum audio sample word length of 24-bits.
The modulator also has built in digital audio processing which is used in the Maestro-50 for sub-woofer processing.
Power stage
The PWM signals for each channel is connected to the inputs of the power stage, where the PWM signals are internally level shifted and fed into two sets of N-channel DMOS power transistors. The power stage is designed in a stereo Bridge-Tied-Load (BTL / full H-bridge) configuration, using a ½ H-bridge (one set of transistors) for each of the four speaker connections.
Passive LC low-pass filter (just prior to speaker terminals)
The PWM output from the power stage filtered just before the speaker terminals using a second order LC low-pass filter. This is where the signal, for the first time, becomes analog.''