Well it’s done.
No more little details, no more what if’s, no more polishing till my fingers bleed! The DeuxAmp project is ready to be jettisoned out into the world.
The system consists of a pre-amp, two mono power amplifiers, and two tower speakers.
The Pre-amp is based upon the amazing SP-14 from Roy Mottram at Vacuum Tube Audio. I had to modify the circuit board a bit to fit my purposes, mainly because I wanted the tubes to be in a radial pattern around the central torroidal transformers on top of the box. His kit has the tube sockets soldered to a PC board, I just chopped off that section of the board and point-to-point wired that half of the circuit. Yeah, that made me a little nervous, but all worked out well, and nothing blew up when I turned it on for the first time! The large volume knob is a vintage knob from an old variac. This was actually the first piece I bought for this part of the project and the rest of the design kind of sprung up around that knob. I wanted it to have a sort of Victor Frankenstein vibe to it.
The Amps themselves are based upon the Dynaco MKIII circuit, and use an upgraded octal driver circuit section from Vacuum Tube Audio. I have never listened to an original, unmodified MKIII, so I have no personal basis for comparison, but I can tell you this, these amps sound fantastic. They crank out 60-watts per channel, which doesn’t sound like a lot these days, but those 60 watts are tube watts, and they certainly pump out the volume.
The speakers are a ported design and are clad in solid walnut and maple. The driver is a Tang-Band W8-1808. At first I was nervous about a single point-source driver, because I’d never heard a speaker with a whizzer cone that sounded for shit, but these things are unbelievable. I get frequencies out out of these speakers that quite honestly shouldn’t be coming from an 8″ driver. It really sounds like there’s a subwoofer in the room, and the highs are crystal clear and not even the slightest bit harsh. The only way I’ve been able to describe it that comes close is that these things breathe – they sound very liquid. The ports on these speakers are unique as well. Originally I was going to just use pre-made plastic ports, but decided it would look cooler if I built my own out of copper. If you scroll down a bit on the blog you will find the build shots from that project.. it was quite a journey.