Interstage, headphone and line output transformers
Our tube amplifier transformers are built in our dual coil single C-core style and can be ordered with a choice of core air-gap for Push-Pull or Single-Ended applications.
The use of C-cores with well-defined air-gap results in an almost constant inductance throughout the whole operating voltage range. For SE transformers, the primary inductance variation due to signal level is less than 7%.
Most of the transformers below are available with amorphous iron C-cores. The amorphous cores are considered to have sonic advantages, but the signal level capability with amorphous core is about 30% less than with a conventional silicon-iron C-core.
|LL1621||1+1 : 1+1||Noninverting interstage / anode choke|
|LL1635||1+1 : 1+1||Interstage. Preferably push pull to push pull. The LL1635 are an old designs and not well |
suited for SE applications. We recommend LL1635/5mA for push-pull preamplifier stages
where some DC imbalance might occur. The LL1635 data sheet is updated to reflect some
limitations in it's use.
|LL1660||1+1+1+1 : 2.5+2.5||Interstage and line output.|
|LL1660S||2.5+2.5 : 2+2||SE - PP and PP - PP Interstage. Internal Faraday shields for improved balance.|
|LL1671||1+1+1+1 : 2+2||High current interstage and line output.|
|LL1677||1+1+1+1 : 4+4||High current interstage transformer (For 300B driving tube).|
|LL1692A||1.75 + 1.75 : 1+1+1+1||Interstage transformer. Compromise between the LL1660 and the LL1671.|
|LL2746||1+1 : 2+2||Stepup 1:2 interstage transformer, designed for two stage amplifiers.|
|LL2753||1+1 : 1+1||For single end to single end applications.|
|LL2756||1+1 : 1+1||For single end to single end applications. High impedance version compared to LL2753.|
|LL2762||1+1 : 1+1||Modified 1660 for SE to SE applications.|
|LL1630||7.2+7.2 : 1+1||Line output, primarily for push pull drive. The LL1630 are an old designs and not well suited for SE applications. |
We recommend LL1630/5mA for push-pull preamplifier stages where some DC imbalance might occur.
|LL1680||9+9 : 1+1+1+1||Line output transformer Based on UTC LS-27 specifications|
|LL1689||9+9 : 1+1+1+1||Line output transformer Based on the LL1660 size and structure|
|LL1930||5.8 + 5.8 : 1+1||Mu metal core transformer for DC-free ("parafeed") line output|
|LL2731||1+1 : 1+1||Low impedance line output transformer|
|LL2745||2.8+2.8 : 1+1+1+1||Line output|
|LL2747||2+2 : 1+1+1+1||Small size low impedance line output transformer, normally used 1:1|
|LL2763||4+4 : 1+1+1+1||Line output transformer based on the LL1660 size and structure. Available in copper or silver wire versions|
|LL2793NC||4+4 : 1+1+1+1||Line output transformer with Nanocrystalline C-core, suitable for preamps, phono stages etcetera.|