Hi guys
I have my first tube preamp in my room and was wondering what tubes (crucial area only) and caps you have tried...also where you got them from..
I have been in touch with Chris Johnson of Parts Express on his super duper upgrade as he is a hour away from work but im in Canada and he wants to charge $60/hr and taxes in USD... Not gonna fly in my house.. besides I have my own tech.
He uses V caps ($$$$) but was curious about Mundorf maybe or????
Also what tubes you found that were smooth..
Not sure all the sources for these items.
I use Mark levinson ml series amps with my awesome ATC super mids and SS 7100 tweeter and have a fully recapped KRELL FPB 600 running all my lows..
Any experiences and help appreciated. ...
That is a good rate and Chris knows his creation and after you listen to it for awhile you could tell tell him what your looking to change in terms of sound quality. Because he created it he will know what to do for you. A good tech is not a designer.......they are two different things.......different talents.

In terms of the preamp and parts. You have two places to look for the biggest bang for the sonic dollar. The output caps should be replaced with the new Jupiter copper foil caps. They are simply the best I have heard.

Your volume control, if it is an Alps or some other pot, then replace it with a nice Shallco stepped Attenuator if you can fit it. Huge improve with these two mods. Thirdly, look at the power supply caps. If they are all electrolytic types, then replace with Clarity TC high voltage film caps.
Here's another option that may work for you. I would call The Cable Company and see what they think. I bought my SF preamp from them and they offered different upgrade packages, along with stock units. You'll get good advice and they have one of the best reputations in the industry. They always sell you what's in your best interest.
And check the relays, they are usually the ones that will create problems with the SF units from that era.
I second BrF's comments but in regards to the SF Power 2 amp. The amp was not involving and definitely did not have that magical 'tube' sound I've heard through many other tube amps, VTL, Counterpoint...... I've read that the SF preamps and amps were voiced in similar fashion. At $5000 retail I had higher expectations from the amp. It seemed darn close to solid state sound but with rolled frequencies at both ends and lack of bass definition and control. I actually went in a different direction and purchased a pair of Monarchy Audio SE-100 Delux MkII amps as factory refurbs for < $1000. These are not perfect amps either but they easily outperformed the SF amp across the board and for considerably less money.
Try the SF preamp in stock form and roll tubes. I suspect you'll end up with something different in the long run - Joule, VAC.....
Happy listening!!!!!
SF SFL-1 was my 1st tube pre. Upgraded to SFL-2 and finally Line 3 then mod to Line 3SE+ by Chris Johnson @ Parts Connexion. Also had Power 3 and then mod to Power 3SE+ by Chris. Coincidentally all pre drove Krell amps. KSA100s, FPB300 and FPB600. SF pre is an excellent match with Krells.

With stock Sovtek or EH 6922, it was hard, flat and SS sounding so did lots of tube rolling. My favorite were Philip Holland or Amperex e88cc/6922. For the 6U8A position, Ediswan CV5065 was my favorite.

I remember Chris offered mod packages so I would contact him for his latest. In my SE+ mods, all caps were Audio Note copper and silver, rewired with silver ... lot of stuff.

PCX bills in US$. With US stop printing $ and the world printing Yens, Euros, Yuans ... US$ has risen so good for US consumers.

Funny story, I was dealing with a Canada Audio company. When CAN$ was higher than US$, his PayPal invoices were in CAN$. Now it has reversed, he tried to bill me in US$ so I asked him to be consistent and change it to CAN$. He refused so out of principle, I canceled the order.