Tuesday 9 August 2022

Koch Twintone II - The Guitar Tube Amplifier that no one's heard of..

 

"I've never heard of it..."
Standard response when someone sees this Amp for the first time.

Hand make Dutch engineering.
Three quality assurance signatures.
See for yourself:

The chassis as it came out of the Cabinet.

Those HT Caps still look good.

Not bad for an 18 year old Amp.
Couldn't find any significant component drift.

Populated with TAD Tubes except for the two JJ EL34's

Transformers are 18 years old.

Pretty sturdy.

Feeling a bit more confident seeing the chassis.

The cabinet is not appealing I'd say.

Here's an ad. for one:

Koch TwinTone 50

Features All-tube circuits, matched Ruby EL34 power tubes, built-in power soak, Accutronics reverb tank, 11-ply birch plywood cabinet, two-button footswitch, independent clean and overdrive channels, independently voiced inputs for single-coil and humbucker pickups, rhythm/solo boost circuit.

Price $2,150

Bias 'out-of-the-box'

Changed generic Chinese Phase Inverter Tube for a 12AX7EH
Changed BIAS to 35mV