Oh it was the one that was actually on the normal channel, but Nik advised me to just leave it on. That lack of the resistor might cause squealing depending on the preamp tubes I was told.

I figured the addition to the rectifier was for added protection. I sometimes use the standby switch on my other tube amp, so this is a good idea to keep them installed, just in case.

I was also wondering, I would like to do a cascade mod but by feeding the output of the TMB channel to the input of the normal channel.. Is this possible, and would the TMB or normal channel's controls be used? Like which channel's controls would be the one used if I were to do that mod? I want to make it switchable with a DPDT switch, and it looks really simple, so I'd like to install this before preparing the amp for its first power up. If anyone knows anything about this, that'd be helpful! Also, what type of switch would I need? I know it would have to handle a certain amount and type of current, but what would those values be? All I know is I'd need a DPDT switch.

Thanks!

I've almost finished my 18 watt TMB head, everything is wired up and ready to go, except I'm stumped on 1 thing, and confused about another.

It seems that in the layout for all of the 18 watts, there should be a 100R resistor going from the middle prong on the normal channel's tone control to the ground bus. The pictures on the site, however, don't show this. Is this a new update, perhaps a mod to bring better performance? I just want to know if I can just use a plain wire from the pot to the ground bus, or if I should drive into town and pick up the resistor. I've used all of the resistors that came with the kit except one, and it doesn't appear to be a 100R. I could be wrong, but my dad was a radio technician in the 80's for awhile and he says it doesn't look familiar. So maybe it was an error in packaging. I don't want to just solder it in there without knowing though. The color bands are what looks to be Brown, Black, Silver?, and Gold. The resistor itself is dark brown, same size as the 100K resistors in the pack.

Another thing I'm confused about is the tube rectifier. In the pictures on the site, they show just wires going to the rectifier socket. However, in the layout, last updated in March, it instructs you to put a capacitor bridging pins 1 and 7, with a diode leading off from each of those pins to a terminal strip, then to the power transformer. (I'm keeping the explanation simple, since I don't really know what I'm talking about, I let my dad figure out where the transformer wires go and I just soldered them up). Are these needed? it seems that this layout is more recent than the pictures, so I think it is a mod to maybe prolong the life of the rectifier tube? I read that somewhere. I've got the diodes and the capacitor hooked up to it anyway, so I just want to be sure that they should be there.

This was my first build, so please keep explanations simple, I'm no electricity expert! My dad just had to explain series and parallel to me, and I only think I partially understand that..

I just finished everything on my 18 watt TMB head, but one part of the layout confused me. On the normal channel, it shows a 100R resistor from the tone pot's middle prong to the ground bus. I have one left over resistor, but it doesn't look like a 100R. The rest of the resistors I double checked and they are all in their right places. What should I do? Is it okay to just leave out that resistor and just use a wire from that prong to the ground bus? I could go out and buy a resistor if it's needed though.

Oh and I was wondering, nik sent me a schematic similar to his layout but he said it wasn't the exact same, but could help a little. It doesn't show the diodes and the capacitor on the tube rectifier, but the layout on the ceriatone page for this amp does show them. Is it best I leave them in?

I'm new to all this.. First diy amp and I'm building with my dad.