An alternative schematic, parafeed amplifier, solves bandwidth problem by blocking direct current from output transformer ( which does not need to be gapped, thus improving its bass response ).
42.
The rating of the amplifier's output power was upgraded to 100 watts and between 1977 1982 an ultra linear output transformer was used, increasing the power to 135 watts.
43.
See paragraphs further down regarding high-power commercially available SET amplifers offering up to 40 watts with no difficulty, following the development of output transformers to overcome the above restrictions.
44.
Large amounts of global negative feedback are not available in tube circuits, due to phase shift in the output transformer, and lack of sufficient gain without large numbers of tubes.
45.
Early transistor audio power amplifiers often had output transformers, but they were eliminated as advances in semiconductors allowed the design of amplifiers with sufficiently low output impedance to drive a loudspeaker directly.
46.
The 1x10 " Vibrolux amp remained a tweed amp until it was upgraded in 1961 to a single 12 " speaker powered by a duet of 6L6 power tubes and a larger output transformer.
47.
The algorithms behind a VVA are based on real vacuum tube non-linearities, mathematically simulating the large-signal transfer functions of various vacuum tubes and output transformers found in amplifier designs.
48.
The reverse flow, short duration, ( about 10 % of the line scan time ) current from both the line output transformer and the horizontal scan coil is discharged again into the EHT supply.
49.
The Circlotron amplifiers often feature direct-coupled outputs, but proper engineering ( with a few well-placed fuses ) ensures that damage to a speaker is no more likely than with an output transformer.
50.
Unicord redesigned the output transformers and told Marshall to use the Unicord design in all units shipped to the U . S . and Marshall could use the design outside the U . S . if they wanted to.
