Tube rolling Question


Hello Tube Rollers
I recently bought my first tube preamp (Blue Circle 21.1). I've noticed I am need of new tubes as the tube whoosh is considerably more noticeable now than 6 months ago. The amp comes with  Electro-Harmonix 6sn7 tubes which I appreciate and dig the sound. I will certainly replace these with a the gold pin model as I like the sound profile. Here's my question:

What other tubes might you recommend for a different "flavor" of sound, and just to have fun with. I am a poor audio guy so please no recommendations for tubes that will cost more than preamp. 

Thanks in advance. 
128x128birdfan
I've tried a bunch over the years. Save your money. There's differences sure but once you get past noisy/old to good/new I just don't think the remaining differences are worth much. Especially when you can get a whole lot more improvement from something like a Synergistic Research Blue Quantum Fuse or a set of ECTs. Either of which cost about what a set of tubes will run you but you get a lot more improvement and unlike the tubes if you don't like em you just send em back.
Electro-Harmonix 6sn7 sounds too bright.

I recommend you to look for Ebay dealer on NOS Silvania vt231 who offer return like this.

https://www.ebay.com/itm/Sylvania-6SN7GT-Chrome-Dome-Tubes-3-HOLE-BB-PLATES-PLATINUM-MATCHED-on-AT1000/264306150011?hash=item3d89dfca7b:g:YwoAAOSws3pcyiHB


One recommendable choice of new production tube is
Shuguang Treasure CV181-Z .

https://www.hifi-amplifiers.com/en/shuguang-treasure-cv181z-electron-tubes-best-matched-pair-p-473.html

It sounds sweet and balanced while NOS Silvania vt231 sounds more dynamic and detailed.

They are compatible with 6sn7.

Thomas
These have very positive attributes and will not break the bank:

 https://www.upscaleaudio.com/collections/preamp-tubes/products/tung-sol-6sn7gtb

 A long time customer with Upscale, otherwise zero affiliation.