Recently upgraded to the Micro 25 RSLS from 25R

[Novemberman]

Hi Drew,

It is tricky trying to recommend sources for NOS tubes but I am sure there are plenty of good suppliers in the USA? Obviously Ebay is a large source of Tubes but knowing the quality and authenticity of what you are buying is not always certain? Maybe approach a few of the large Tube suppliers and ask what they have, sometimes they have tubes that may not always be advertised.

Other than that keep an eye open on the forums and indeed this forum as both Tesla tubes and Brimar tubes have been sold here. In fact there were some fantastic value Tesla tubes available recently in the classified section.

Hi Jimbo ,
Well , I’ve rolled the dice and purchased my first ever NOS tubes . I purchased 2 matched 1960 NOS RCA black plate 12bh7a tubes to replace the 2 stock JJ ECC99 tubes in my new RSLS . The dealer seems reputable but time will tell . I haven’t received the NOS yet , but in the meantime my RSLS actually sounds awesome with the Croft supplied stock JJ’s. Glenn Croft is some kind of magician .
Best ,
Drew

[walpurgis]

How long do valves have to be 'warehoused' before they become NOS? Surely the popular choices must be getting thin on the ground...........or is somebody manufacturing new fake NOS? (yes, I know it is alleged to happen)

[Jimbo]

Glad you are getting great performance from your RSLS with stock JJ Tesla valves, it should move up another level with NOS RCA Black plate 12BH7a. I will be using one of those myself in my 25R line stage.

Interesting I found JJ valves sounded fine in regulation stage but not the phono stage. NOS Tesla were far better in this position.

[Novemberman]

Glad you are getting great performance from your RSLS with stock JJ Tesla valves, it should move up another level with NOS RCA Black plate 12BH7a. I will be using one of those myself in my 25R line stage.

Interesting I found JJ valves sounded fine in regulation stage but not the phono stage. NOS Tesla were far better in this position.

Hi Jimbo ,
I received and installed my NOS RCA Black Plate 12bh7a tubes . What a huge up tick in performance the NOS tubes bring the the RSLS - quite shocking actually . Ultra vivid and clear - solo instruments sound huge coming out of my little Falcon Gold Badge Ls35a speakers. It almost sounds like I’ve installed a much more powerful amp . I’m amazed

[Jimbo]

Hi Jimbo ,
I received and installed my NOS RCA Black Plate 12bh7a tubes . What a huge up tick in performance the NOS tubes bring the the RSLS - quite shocking actually . Ultra vivid and clear - solo instruments sound huge coming out of my little Falcon Gold Badge Ls35a speakers. It almost sounds like I’ve installed a much more powerful amp . I’m amazed

Excellent Drew and good choice of 12BH7a, I use the very same one in my line stage and the difference as you say is shocking. It produces the same vivid/clear sound I get through my NOS Teslas in the phono stage. The extra boost you have to your perceived power output maybe the fact the RCA tests very well and is performing at the top of its output range?