Does anyone know what output transistors were used in the Quatre DLH100 amplifier? This amp came before the Gain Cell models. I have one on the bench now and someone replaced the outputs with MJ15022/25s and just by coincidence I just finished a Son of Ampzilla from the same friend that had the same pair of outputs, even the date codes were the same. Both had been to the same repair shop years ago. I drew a schematic for it and it is scarily close the SWTPC Universal Tiger, same driver/output configuration, PNPs on the + rail and NPNs on the - rail. The only difference is the Tiger has 50% feedback between the driver/output and this amp has 100% and therefore no voltage gain in the output stage and possibly none of the problems of the Tigers. The rest of the amp is untouched except for the outputs. Just wondering if the MJ802/4502 combo as in the Tiger could be the originals.