Model A:
Smooth, clean and convincing

 

It takes some time to understand this simple fact about modern linear power amp chips design: the chip is not the limiting factor. It can be anything. The limit is design around it.

And with this design, Audial Model A represents here today’s state of the art.

It is tonally rich, and easy on ear. Precise and clean, and smooth. Dynamic and convincing. Three dimensional, with body and weight.

In a word, it is a highest performing amplifier, and it is offered at very affordable price.

● Linear IC based stereo amplifier

● Low impedance shunt potentiometer, as ultimate volume control

● 15 cm total signal path length (input to output)

● Stringent selection of highest quality parts

● 25 W and 50 W optimized versions

● Machined and engraved aluminum chassis

● Optional features available

 

Premium parts

Model A can be shipped with premium parts. These include:

– pure copper input and output connectors

– uninsulated internal wiring

– cermet potentiometer

 

One or two inputs

For purists, one input has all the advantages, as it just skips any switch.

Still, toggle (a.k.a. kip) switch can be acceptable. It is limited to two inputs, however usually two inputs are actually enough. Also, to avoid any significant internal signal wiring, this switch is located at back plate, next to input connectors.

It was decided to avoid compromises associated to rotary switch, which is required for more than two inputs.

 

Volume control

A low impedance shunt potentiometer is normally installed, and this is the best sounding volume control for this (and probably any other) amp.

However, tube sources usually do not drive well such a load (as low as 750 Ohm). That is why the option with more conventional 25 – 50 kOhm input impedance is available.

In addition, Model A can be also shipped as power amplifier only, with no volume control at all, and in this case it has 47 kOhm input impedance. Such an option is suggested to users with, say, tube source and TVC preamp.

 

Power

Model A is available as 25 W and 50 W version. These options are offered to let Model A do its best in actual environment.

The only real difference between 25 W and 50 W version is in supply voltage.

Please note that, when ordering, unless 50 W is specified, a 25 W version is assumed. In most cases it is (more than) enough in home use, and hence recommended option.

Please note that the change in power does not change the price.

 

Input:

RCA, one or two pairs, with or without volume control

1 V RMS is required for full power, typical

Several options are offered, with input impedances between 750 Ohm and 47 kOhm

 

Power:

25 W / 8 Ohm, 40 W / 4 Ohm

50 W / 8 Ohm version is also available

 

Gain:

29 dB, typical

 

Frequency Response:

20 Hz – 100 kHz, +/- 0.5 dB, typical

The input is directly coupled, but amplifier is blocked for DC gain, for loudspeakers safety

 

Absolute Phase:

Correct

 

Harmonic Distortion (@ full power):

0.01% @ 1 kHz

0.04% across the audio band, worst case

 

Intermodulation Distortion (@ full power):

0.04%

 

Mains voltage:

220-240VAC / 50-60Hz, IEC (C14) connector

110-120VAC / 50-60Hz also available

 

Dimensions (W x D x H):

352 x 255 x 75 mm

 

Net Weight:

Approx. 6 kg

 

  Download PDF

 

 

 

 

 

 

 

Recommended topics:

Introducing the Model A

Designing the ultimate monolithic amplifier

Sweet spot of amplifier power

Model A, one year later: Binding posts

Model A volume control

 

Model A review at:

www.ap-linux.com/news/audial-model-a-back-to-the-music