ASV AOT-40
Output transformer for tube amplifiers
[AOT-40 technical data] [Other transformers] [Chokes]
A high-quality output transformer is the heart of
the tube amplifier. A poor output transformer fitted in a well designed amplifier will
spoil its performance. Needless to say that the design and optimization of an output transformer takes high skill and know-how because performance requirements are complex and high. The transformer must deliver adequate and constant power without core saturation. It should provide wide frequency bandwidth at a minimum distortion. Moreover, it should provide a constant outstanding performance to retain the open, spacious qualities of recorded music. The sound quality of ASV transformers is exceptional: low distortion and an extremely wide frequency and dynamic range. The present AOT-40 transformer has a double C core and has been carefully wound, has no internal solder joints, is impregnated and encapsulated in metal housing. There are two threaded mounting bolts for easy installation. Applications Typical applications include push-pull triode, ultralinear and pentode power tube configurations. It could be equally used in new designs and for upgrading old ones. |
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ASV AOT-40 transformer | Bottom side with connections |
Technical specifications for the ASV AOT-40 transformer
Suitable tube types | EL 34, 6CA7, 6L6, two pairs EL 84 |
Nominal output power | 40 W |
Nominal primary impedance | 4.7 kohm |
Nominal secondary impedance | 6 ohm |
Maximum dc primary current | 120 mA |
Turns ratio | 14+14 : 1 |
Screen grid tap | 40% |
Frequency range (with resistive load at 1 mW) |
17 Hz - 125 kHz (-1 dB) 7 Hz - 135 kHz (-3 dB) |
Power bandwidth start (-3 dB) | 17 Hz |
Primary inductance, Lp (a-a) | 320 H (at 230 V, 50 Hz) |
Primary leakage ind., Lsp (a-a) | 6.6 mH |
Primary capacitance (a-a) | 290 pF |
Primary resistance | 154 ohm |
Secondary resistance | 0.20 ohm |
Insertion loss | 0.44 dB |
Quality factor (Lp/Lsp) | 48,500 |
Frequency decade factor | 4.3 |
Harmonic distortion (with measuring amplifier at 1 W, 1 kHz) |
<0.04% |
Measures | 100x100 mm, height 90 mm |
Weight | 3.3 kg |
Other transformers
for tube amplifiers
ASV filter chokes are constructed with high quality double C cores with precisely defined air gap. They can be supplied with mounting brackets or encapsulated in metal housing. On special request, we can supply chokes with inductances and DC currents different than those in the table. |
ASV filter chokes - Specifications
Type | Nominal inductance (H) | Nominal DC current (mA) |
D 16-160 | 16 |
160 |
D 10-200 | 10 | 200 |
D 6-260 | 6 | 260 |
D 4-320 | 4 | 320 |
D 2-400 | 2.5 | 400 |
D 1-520 | 1.5 | 520 |