Vibrant HiFi

iTRON

All Avantgarde speakers have an option to have the horns powered by their iTRON amplifier.  This would mean that the speakers can be fully active.  Simply run a pair of XLR’s from your preamp over to the speaker and we have music.  But the question is, what is the iTRON and what makes it so special?

iTRON is a full class A, zero negative feedback amplifier with a single output transitor.  It is also multi-channel. For the Trio the iTRON is a 3-channel amplifier.  In the Mezzo, Duo or Uno is it is a 2-channel amplifier. It provides 3 watts to each horn. 3 watts may not seem like much but with 107 to 109 dB efficiency this amplifier is capable of driving the speaker to effortless peaks over 112 dB.  If you have experience with class A solid state amplifier then you will know the sound they produce – warm and powerful.  All of this alone would make the iTRON a superb choice for the Avantgarde speakers.  But this is not what makes the iTRON truly special.  It is a remarkable because it is a current amplifier.

Almost all amplifiers in high-end audio are voltage amplifiers.  This means they take the music signal coming from the preamp as an input voltage and amplify it.  (Usually in the range of 26 – 31 dB of gain)  However, electrical current, not voltage, is needed because current in the voice coil is what interacts with the magnetic field of the driver to make them move.  A voltage amplifier works by converting the voltage to current at the voice coil due to its internal resistance (4 ohm, 8 ohm, 16 ohm etc) following ohms law – V= I*R.

The iTRON is a totally different type of amplifier. It is what is called a “Current Amplifier”.  This means it amplifies the current not the voltage.  This is exactly what the drivers need.  There is no conversion at the voice coil from voltage to current and there are no capacitors, inductors or resistors that the signal has to pass through in order to split the signal by frequency.  All of this results in up to 30 dB less distortion and a much faster rise time in response to the signal which equates to speed.

There is an additional feature with the iTron that we can not get from an outboard amplifier – flexibility.  Each iTron amplifier has six switches.  Three of the switches control the absolute gain of the amplifier.  This allows us to turn the gain of the amplifier down by bypassing gain stages.  This is useful as each time a gain stage is eliminated the noise floor drops.  The other three switches are even more significant.  They allow independent control of the gain of each horn by +/- 1.5 dB.  This allows for tailoring the sound to fit the room and personal listening preference.  If we want more body we could boost the lower horn by 1.5 dB.  If we want less treble we could cut the tweeter horn by 1.5 dB.  The switches allow us to the ability to really dial in the sound to suit our taste.

In summary, the iTRON is a flexible, multichannel, 3 watt per channel, full class A, zero negative feedback, current amplifier.  It is a low distortion, super-fast music making machine.  This amplifier was developed and patented by Avantgarde acoustic and is manufacture at their facility in Germany.  It is the perfect mate to the Avantgarde speakers.

For those interested in a very technical description of current amplifiers I recommend the book:

“Current-Driving of Loudspeakers: Eliminating Major Distortion and Interference Effects by the Physically Correct Operation Method“.  It is available on Amazon.