Tram2 - DHT OTL Linestage
The Tram2 starts with good layout. We wanted a single chassis solution together with power transformer. So transformer at the front, triodes at the back close to input/output connections. Tube rectifier and 6AS7 closest to the transformer.
B+ is supplied from the ultra low noise film cap power supply module and the cathode supply comes from our filament supply module with added capacitance.
The Tram2 mounts the triodes on the 3mm tube subplate which is in turn mounted to the chassis with compliant isomount standoffs. Knuckle rap on the chassis doesn't transfer so we've done well.
We have provisioned 3 outputs: +6dB, -3dB and -12dB. The user needs to select in system but in general: amplifiers with input sensitivity of 2 to 6v would match +6dB outputs; 0.7v - 2v amps: -3dB outputs; below 0.7v amps: -12dB outputs.
The Tram2 can comfortably handle amplifier loads down to 2k ohm.
Why DHT OTL linestage?
DHT sound better. On the test bench we get very low noise and very low distortion. What little distortion is there, is of the single ended type which many feel to be consonant with the sound of music.
The Tram2 as presented can use either 45 or 2a3 types, just plug and play.
What you get is very low distortion, linear output with all the tonality offered by direct heated triodes as close to the source as possible.
Beautiful TJ tubes for your amplifier: