SURFING MUSIC SOUND-WAVES

Some of the best preamp/input tubes are the real oldies - the DHT26  ( mind the inherent annoying hummmm thou....)  and its related detector tubes ,  the IDHT 76 (the tube with a 5-pin base), and its predecessors - the 56, 37, or the grand-daddy of all IDHT (indirect-heated triodes), the 27.   The 27 and 56 require 2.5V AC for the heater vs. of the more typical 6.3V AC for the 37, 76.

 You might think that really old tubes - designs dating from the early Thirties - sound "vintage" and "tubey." Actually, they don't !!! . Tubes in this  family  actually sound fast, quick, and incisive, and have very low distortion, along with a favorable distribution of harmonics, much better than the "current ordinary" 9-pins of nowadays.

 If you want a traditional mellow "vintage" sound, go for  a 12AU7 or its family , the tube used almost universally in to-date amplifiers and many guitar amps - but mind you ,  it  also  has distortion many times higher than the early Thirties tubes.

This line-amp will be  a "plug & play " using  these  5-pin early 1930  single triodes .

The output topology will use Line-output-transformers . A choice of some LOT's from my   junk-yard:

15July 2009

The nice wooden chassis (chassis made by Leonard  in Bandung city,  stunning red-wine color stained) , finished the brush-finished top plates.

 Mock-up on finished top plate

 02-09Aug 2009:  Chassis  process

 22 August 2009

The chassis is finally completed.

Its time for the internal wiring soldering . I hope to get this little amplifier singing by end of August 2009

 Stay tuned........................