Saturday, December 3, 2016

New Audio Frontiers Stradivari Phono





















































The circuitry has been implemented through three stages, all triode. The first two, between which has been inserted the network R.I.A.A. equalization, are used for the amplification of the signal coming from a cartridge of the type MM, while the third performs a lowering of the output impedance in order to be able to drive without no difficulty line stages which have a low input impedance and / or high capacity due to interconnecting cables also rather long.

For the use of pick-ups of type MC, further amplification has been delegated to two transformers STEP-UP, one for each channel, with the mu-metal core and windings in silver rather than to a further stage of the active type in order to reduce noise and maintain high quality sound. In the front was inserted a potentiometer in order to be able to adjust the load of MC pick up.

Within the device has several peculiarities. It was adopted the choice of using the solution of 2 frames in order to minimize any problems of uptake of electrical noise coming from the power supply.  In the latter the straightening of the anode voltage is implemented through a dual triode vacuum type EZ 81 and level out by two cells with PI Greek inductive, one per channel. The power supply of all the filaments of the tubes tubes of the signal is, contrariwise, stabilized.

Another special feature is that of having chosen to realize a printed circuit where the path of the tracks is identical in both channels to make sure that even the smallest and unavoidable parasitism capacitive are identical between them. The components have been chosen at the highest level which includes and especially stand out  the capacitors MICA SILVER used in RIAA EQ, high stability, low loss and minimum tolerance.



TECHNICAL CHARACTERISTICS

Sensitivity input impedance
Phono MM 47 KOhm / MC

Inputs phono
2 RCA

Output phono
1 RCA

Gain
70 dB

Frequency response
20 – 50K within 0,5 dB

Signal / noise ratio
90 dB

Dimensions
29 x 15 x 40 cm. (W x H x D)

Dimensions separate power supply unit
29 x 15 x 40 cm. (W x H x D)

Net weight
25 kg. Couple