Most will probably agree, that you'll get the best performance from vintage tubes, and you'll no doubt pay the price for them as well.
I don't believe Kevin at Upscale carries the NOS RCA 5751 Triple Mica Blackplates anymore, but an email to him won't cost anything, and he may have some good suggestions for you for your particular application.
He's helped me in the past.
I cannot comment on the Ei, having never used it, and I as well don't consider myself any type of Tube Guru.
But, the GT Mullards, provided you get some good ones (I hear there has been some variability), are a good tube, and the price of admission is certainly reasonable enough. Kevin weeds through, tests-grades all Tubes he sells, and I believe he even backs them with a warrantee.
I understand Aspen Pittman has liquidated Groove Tubes, so these GT Mullards might start getting hard to acquire as well? Mark
I don't believe Kevin at Upscale carries the NOS RCA 5751 Triple Mica Blackplates anymore, but an email to him won't cost anything, and he may have some good suggestions for you for your particular application.
He's helped me in the past.
I cannot comment on the Ei, having never used it, and I as well don't consider myself any type of Tube Guru.
But, the GT Mullards, provided you get some good ones (I hear there has been some variability), are a good tube, and the price of admission is certainly reasonable enough. Kevin weeds through, tests-grades all Tubes he sells, and I believe he even backs them with a warrantee.
I understand Aspen Pittman has liquidated Groove Tubes, so these GT Mullards might start getting hard to acquire as well? Mark