Spalted-Alder

Yesterday I auditioned some new reissue Tung-Sol 6L6GC STR tubes in the 6L6 “Spalted Alder” amp. I was quite surprised at the results.

Remember when I said that you can’t always get what you want? Well, it turns out you can. At least in this case. Especially if you are willing to shift some priorities.

Have you ever made a mistake? Not a typical everyday little mistake like forgetting to run an errand, but a blunder of such proportions that you’re shocked by your foolishness? One that leaves you thinking you couldn’t have been that naive, that foolish? Well I did. And it left me with significant embarrassment, as well as some smoke coming out of an amplifier.

The complete project description page for the 6L6 SE-UL amplifier is now live and can be found at the following link: The 6L6 “Spalted Alder” Amp.

I spent some time this afternoon taking technical performance data on the new amp. Unsurprisingly, the technical data is in agreement with my impressions from the excellent listening session yesterday. This amp is a solid performer and just what I wanted from the design.

This morning I took a little time to complete the major wiring of the amplifier. Everything is in place except the B+ dropping resistor.

In the last few days I’ve managed to get most of the wiring on the 6L6 SE-UL top plate complete. This includes all the preposterously large power supply filter capacitors.

I’m still waiting for the top plate paint to harden. But that didn’t keep me from getting some wiring done on the chassis today.

I suppose by now everyone is wondering what has happened to the 6L6 SE-UL amp project. Well, so am I. Kind of.

So the black finish has set up and I think it looks far better than the grey. So, again, as long as there’s no uproarious outcry, I’ll be going with the black. I think this finish ties the whole project together much better than the grey would have done.

As promised, after the primer was fully dry I took the power transformer down to my shop and put it together with the grey top on the chassis. Whereas the grey would make for an interesting look, I think I’ll like the black better. So unless there’s an uproarious outcry from the amp builders of the world, that’s the way I’ll be going.

Sorry about the title; I couldn’t resist. I got some time today so I applied the primer to the metal for the 6L6 SE-UL amp. The primer takes 24 hours to fully dry so tomorrow I’ll place it in the amp with an Edcor transformer on top and show everyone what the grey looks like with the spalted alder.

I now have five coats of oil on the amp chassis and the color is incredible. But this finish isn’t going to be like the last couple of projects. The wood is just too different.

The second coat of oil went on the 6L6 SE-UL chassis this morning. The oil is bringing out something in the wood which was totally unexpected; color!

Today I finished putting the final shaping details on the 6L6 SE-UL spalted alder chassis. All it needs now is a final sanding and the oil finish.

Today I made my final decisions about which piece of wood would go in each position and orientation. This amp chassis is going to be a work of art!

I just got a notification from Edcor. The power transformer I ordered for the 6L6/KT88 SE-UL Amplifier on the 2nd of May (just 9 days ago) shipped today! I thought I was going to have a lot more time to get the spalted alder chassis into shape.

Even though I’m waiting on a power transformer and some oversized components for the 6L6 SE-UL amp that doesn’t mean that all progress has come to a standstill. The new amp needs a chassis. And a new chassis means it’s lumber selection time.

The gear switching I’ve been doing on this rainy afternoon has been putting the 6AS7 “Purpleheart” SET in the “finished” column of the ledger and getting to work on the upcoming 6L6 SE-UL amp. And I’ve already run into a delay.