2.14.2013

DIY KT66 PP amplifier

This is a DIY KT66 PP amplifier that I built two years ago. The schematic is based on British Leak's products. The driver and phase inversion section uses Leak TL50+'s design with EF86 as the driver and 12AT7 as the phase splitter. The power amplifier section uses TL12 Point One's design. I tried using GZ34 as rectifier and finally decided to use 5R4 instead.

The power and output transformers are Chinese made. KT66s are Chinese made too. Can't afford to buy Genelax used or NOS ones. The sound is just so so, a bit sloppy compared to my another EL84 PP. I like the look though. I will replace the Chinese made output trannies with a pair of Japanese Tango when I have time. But it's not likely to happen this year.

JBL 4310s

Got a pair of JBL 4310s from eBay a couple of years ago. They were in poor condition when arrived. A cabinet was cracked during shipping. The grey surfaces were painted in black ugly. One 2212 had rubbed coil and I finally had to replace it with a spare 123A-1. Despite the poor condition, they sound quite nice to my ears. Compared to my bass shy Klipsch Heresy, these 4310s can render more details and of course have better bass.

When driven with my DIY KT66 PP amplifier, the combo can handle rock music much better than the KT66 with Heresies. I can finally feel the energies of Red Hot Chili Peppers, Pink Floyd, Jamiroquai, Jimi Hendrix, and even Metallica from the combo. Although far from satisfactory, these 4310s seem to have more potential than the Heresies.