By the way, the tube in that thing is a WWII suplus, obsolete, dual tetrode VHF transmitting tube. It was never designed for audio use, and primarily designed for what is called "class C" meaning as far from linear operation that you can get. Tube audio amps must be class A operation, or B (Pushpull) or in between AKA "AB"
A single tube that is not push pull cannot produce decent audio if it is anything but class A operation
Here is the original RCA datasheet
http://www.r-type.org/pdfs/832a.pdf
The reason these types of tubes were made at all is in fact because of early development at VHF frequencies. Some of the limiting factors at VHS is LEAD LENGTH which includes the wiring inside the tube, and INTERELECTRODE CAPACITANCE AKA "less is better"
So the thing about dual triod/ tetrode tubes is, you wired them up in push pull and with each tube set of elements nearly identical, they were easier to maintain "balance.
Also push pull means that each tube conducts during 1/2 the sine wave output, so that in effect, each tube is operating at 1/2 the frequency. AKA, if you had two tubs rated for say, 50 MHz and you were trying to operate them near 100 Mhz, you could use two in push pull and the effective freq limit is thus doubled
Here is an 829B VHF amplifier, which is very similar to what this 832A but would have been used for
