Original breadboard overview.

Clear-coated natural light oak panels.

This amp incorporates a true Loftin-White (LW) configuration.
Please write to me if you are interested in making one, but don't get me started on the LW subject!
Some folks make amps that are called LW but in truth are not.
Others have duplicated the original LW which is not entirely suitable for high end audio.
THIS amp follows a middle ground, incorporating the bias stability features and direct coupling of the original, while eliminating or altering those parts of the original suitable only for radio signal detection and gain control.
Bottom line is there is no true LW suitable for hi-fi unless these changes are made.

In the requirement of a true LW, a tetrode input tube was selected; in this case the 6EV5. It is biased for most linear operation with a slight bent to complement the output tube characteristic. The tetrode receives its screen grid stabilization from the cathode of the output tube and its plate is direct coupled to the output tube grid. The amp will work correctly with any 6EV5 (in the spirit of the original LW), but due to the power disappation considerations of the 1626 output tube, a user adjustable output bias was incorporated by means of adjustment at the input tube cathode. The 6EV5 heaters are DC operated for low noise.

Solid hard oak interior supports.
High-quality NEW and NOS parts used throughout.

The output tubes are 1626, the so-called "Darling" tube and the output stage makes about 750mW power per channel. The output trannys are vintage RCA with both 8 and 4 ohm taps.

So what about the sound?
I've built a number of Darling type amps, and played them on many speakers. I find these amps to sound (what I call) "delicate". They have soft fingers that lightly reveal the inner workings of the music. Even the bass is breathed with detail that some more powerful amps seem to gloss over. In general the Darling has a slightly "warm" character. It is this delicate touch that I appreciate about Darling amplifiers. In this Loftin-White version, everything has a more solid feel than my previous Darlings. The lower bass is tighter and overall response is more extended; the imaging a bit sharper without losing the depth the Darling is famous for. Perhaps the DC coupling is involved with that. Playing on Bob's FB-16s, the solid bass added just the right touch to that fine speaker, giving just the right balance when played below the point where the room itself plays too much a part in the experience. Know what I mean?

Amp at GPAF May, 2006.