Two "Different" Rectifier Tubes in Pair OK???

In my Cary SLA-70Sig amp the two NOS 5V4G rectifier tubes (Sylvania, and RCA) are of different construction, and there is no problem.
Cary informed me that both work together, not on separate channels.
In actual use in this amp, one can hear differences in the sonic performance when using either two of the same, or two different NOS 5V4G tubes.
In which amp are your rectifier tubes being inserted?

To clarify earlier posting,
both channels sound the same in the Cary SLA-70Sig amp, since each rectifier tube affects both channels. There is no right or left allocation with this dual rectifier tube design.

I'm using Cary 2a3 monoblocs. I wonder how mono's make a differencde.

If you play one amp through one speaker in order to hear how one rectifier tube in one amp sounds, and then switch to the differently constructed rectifier tube in this single amp, you will probably hear a subtle difference.
Or, just relax, and play your system, which will sound glorious with those amps.
I must inform you that if you choose to simply enjoy the beautiful sound of your system with "mis-matched" rectifier tubes, then your membership in the audiophilia nervosa club is cancelled :>)