oldangelmidnight wrote: ↑Tue Oct 15, 2024 7:23 am
How does it sound?
And do you want to build me one?
Sounds in the same ballpark as the two others. From what I've heard so far, and logically deduced from the fact that there can, and will be variances between tubes, no two sound exactly the same. There's no "good" or "bad" mind you, just different personalities. Like children. For example, the black knob original is very stable, and not microphonic at all, while the pink knob one is less stable, and exhibits some microphonic ringing from the tubes at certain settings (or, from any external vibrations). My clone sits right in between them, decent stability, with only a touch of microphonic ringing. I must admit though, I didn't spend any time rolling a bunch of different tubes through the clone. The first 3 that I grabbed are what went into it, and they sound fine. It does whatever the two originals can do. The only upgrade we made with the clone was beefing up the tube filament power regulator to a TO220 size unit. I found that the originals created too much load on the small TO92 size regulator, which in turn created quite a voltage sag on the entire supply side, which then trickled down to everything downstream.
Sorry, I just have to much work on the bench at the moment to take on any build commissions. Lots of great builders around though, maybe hit the Shark Tank, and see if someone nibbles on your request. If I had to choose someone to build mine, it would be govmnt_lacky (he mostly hangs over at DIYSB). He's not cheap, but his build work is top notch, in every respect. He has my AAAAA seal of approval.
oldangelmidnight wrote: ↑Tue Oct 15, 2024 7:24 am
Were the tubes soldered in the original? Would the ever need to be replaced?
Yes, they are soldered in the originals, with small pads. A real PITA to work on, since they were a source of issues with both the originals. On both units, I found tube pins that were not even completely passed through the board when soldered. Just a lump of solder between the pin and the top side of board, which eventually cracked, creating a non-connection. While I used sockets in mine for potential testing, Phil also designed the DEFX PCB with bigger beefier pads to allow for potential reworking in the future. I simply soldered the pins to the sockets when I was done, like I always do. But, to be honest, these tubes are not operating anywhere near their maximum capacities, so unless you really abuse it physically/mechanically, the tubes should outlive you.
The other major source of issues with the originals is broken solder joints where the pots connect to the board. Due the height of the rotary switch deck, the right angle pins on the pots that were used for these builds are too short, and are barely inserted into the board. They don't even make it out the other side, but end up sitting flush, so the only place you have to build up any solder joint is on the pot side of the board. Unfortunately, this creates a lot of stress on the joint, which ends up cracking the solder, or in some cases (as with the pink knobber) the pot breaks free completely. I had to reflow all the pot joints on both original units, and the Gain 2 pot in the pink unit had broken off completely, falling back into the enclosure when I pulled the board! Needless to say, I suspect more unit failures will appear as time goes on.
