I had a lot of trouble with SV20h, but actually listening to the sound, I think 1987 page is better Two EL34s and one ECC83 (or 12AX7) output tube, consisting of two ECC832 free tubes. Typically, when the volume increases, the break-up starts and gains are obtained, so if you don't just use the clean tone, you need to have some volume.
The vintage issue version I purchased was a PCB board and also a transparent serial FX Loop terminal was added at the great request of existing customers. Of course, there is a bypass button and next to it is a button that can reduce its signal strength if the signal coming from the Sandreturn terminal is strong. If you use a spatial pedal or rack effect, it is transparent and well received. It's a characteristic of Marshall, but he's really good at taking a pedal, whether it's front or back. There is no way to tell the difference from the hand-wired version produced by soldering each part on the turret board, but if you look at foreign sites or forums, the difference is really insufficient, and the PCB version is more advantageous in terms of life. HW may be better if it is a purchase for investment, but I think the player will be able to feel the same martial sound no matter what version he buys.If you really like the original, vintage tone, and if you like hard rock, you don't need any more choices except 1959. With an attenuator and a rack-type space meter that can be used like a master volume, you can enjoy the saturated tone of the power tube at home