I'm lucky. Don't have issues with RFI/EMI where I live. AV-I'd like to hear how the mods Jeremy has made worked out with the Ember as I  consider it to be an excellent amp and a great value as well. Assuming he is grounding the metal chassis?

Yep. He's also installing a supercharger, lowering the gain, doing a line out disconnect (to cut it when headphones are plugged in), and generally shifting everything to the V.2 specs. I'm also picking up one of the 6SN7 adapters and having him install a spiffy volume knob.

I'm going to try to track down a decent budget 6SN7 tube to try it out.

Wish you had said something. I had a Sylvania green with me.  Never time to experiment at meets. I also think there might of been a  lot of RFI in the building. Might be what you were hearing?  Next experiment in Monrovia.  I'll bring all my 6SN7's. Anax- if you have a Chormedome you like please bring it.  Want to explore this further.

I think they could use a Sylvania Chromedome with green letters. A real Chromedome. Having chrome on top doesn't make it a Chromedome. They tend to have sweeter, more coherent and fluid signature. I think that would be beneficial based on what I heard last.

Update: this was a fantastic recommendation. I received my updated Ember from Jeremy yesterday and tried it out with the Admiral Black Glass 6SN7GT that he provided with the 6SN7 adapter. That tube performed worse than the other Amperex and Telefunken tubes I was already using. The Sylvania 6SN7GTB '53 Chrometop that I picked up is much better all around - really great tube.

Behold, my shitty smartphone pictures!