Tubes for Schiit Saga

Thanks. I like it with standard tube in current set up. Just curious if others have found some modest price tubes that work well 

I have a Saga+ which, as you likely know, has a passive mode which only acts as a volume control, and an active mode which uses the tube as a unity gain buffer. The tube that came with my preamp is incredibly neutral. You have to listen very closely to spot a difference between the passive and active modes, though the active mode is very slightly smoother, though with no loss of highs or dynamics.  

Personally, I'm not going to spend any time tube rolling. I like the sound I'm getting from the Saga as-is.

I replaced the default tube in the Vali2 with a Telefunken Black Diamond from Tube Depot and even with this cheap headphone amp ($150) and Fiil headphones the improvement is very noticeable sounding smoother and more musical - more relaxing to listen to. 
Does anyone know who makes the $10 tubes that Schiit uses?

I ended up with a Tung-Sol from Upscale Audio, and am very happy with it ( under$50 )...I just went with their top recommendation...

@jl35 i recently got the safa idk if you are talking about the vali2 or saga but the stock tubes schiit tends to use in the pre amps are VERY neutral . can barely tell a difference. but i just switched to a ken rad vt 231 smoked and the difference is huge. such an upgrade. im also getting the vali 2+ would the tung sol you got fit in the vali 2 or were you talking about the SAGA?