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Z565-48 17.5 (35W) Watt Triode USA Output Transformer for Dynaco ST-35 MADE IN USA

For the Dimensional diagram and hookup sheet for this unit please click here (Adobe Acrobat Reader required)

Our reproduction of the Dynaco Z565 output transformer as used on the Dynaco (tm) ST35 and SCA35 amplifiers, except that the output taps are 4 and 8 ohms, rather than the original 8 and 16 ohms, thus making this transformer useful for many do-it-yourself projects where an original Z565 can't be used due to its lack of a 4 ohm output tap. The primary is wound the same as the original 565, same number of turns, sections and wire size, using the same patented Dynaco winding method, and made on the same core size and material. Only the secondaries have been adjusted to accommodate the different taps, and improved insulation material used (thus making the transformer more resistant to abuse).
This transformer has what you'd expect out of a Dynaco transformer, like healthy low frequency inductance (over 1000 henries at 60 Hz), high resistance to distortion caused by output tube imbalance, and low distortion overall.
Brand new production, MADE IN USA.

There are plenty of neat DIY projects one can build with these transformers, such as the one at
These types of transformers can be used with many tube types, such as 6BQ5/EL84, 6V6-GT, 6AQ5, 6BM8/ECL82, cathode-biased 807, 6L6, KT66 and others.
For the results of bench test comparison of our Z565-48 to the original Dynaco Z565, please click here
Note that in the examples given in the preceding, at high frequencies the noise/THD of the amplifier is greater than that of the transformer: the actual bench tested distortion figures at full power (17.5 watts) for the transformer itself are as follows: 1KHz 0.019%, 10 KHz 0.032% 15 KHz 0.029% 30 KHz 0.048% 40 KHz 0.058 %. This is practically within the measuring margin of error the same as of the original Dynaco unit. The UL taps are at 25%, per Dynaco spec for this output.
Here's a similar comparison of the original Dynaco, Magnequest, Handwound, and two models of Hammond transformers (Acrobat plugin required to view).
Note in particular the comparison between the Dynaco part and the Hammond 1650F, comparably priced to our unit.
Transformer specs are: 8000 ohms CT primary with screen taps, 4 & 8 ohm secondary.
20 Hz to 20 KHz response at 17.5W, within 1 db (30-15 KHz @ 35W)
Max DC per side (suggested) 80 ma.
Height 3 inches (75 mm) width 2 1/2 inches (63 mm), depth over covers 3 1/8 inches (80 mm), mounting centers are 2 inches (52 mm) by 2 1/4 inches (55 mm).


Z565-48 END BELL REPLACEMENT COVER z565endbell$9.95

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