Deja Vu is a very unusual audio store. The Deja Vu pushpull amps being discussed here (I own a Deja Vu pushpull 45) were built by a Russian living in the DC area, with the owner of the store providing the "voicing" (he would listen and say whether he liked a particular design or part change). The Russian designer/builder is back in Russia, so newer builds of that particular design are sort of on hold. The store currently is selling amps built by someone in Italy who builds exclusively for the store. These designs are quite special too--they use primarily very old vintage parts, particularly Western Electric parts. The store owner does some of the parts acquisition for the builder. The linestages are custom built (you can have it how you want--with phonostage, with remote volume control, even with built in crossover, and some that are designed with output transformers to couple with an amp with matching input transformers). The store also designs and builds high efficiency speakers, again using some very expensive vintage drivers.
Getting back to the Deja Vu pushpull amps, these were built mostly with somewhat difficult to find vintage output transfomers. Mine have Acrosound TO-330 transformers (ultralinear transformers, but with the feedback loops not used because the tubes are triodes). I think others were built with Chicago transformers as well. I don't use this amp any more, preferring my current 2a3 SET amp, but, that amp costs many multiples of the Deja Vu amp (now on loan to a friend). The store often had some very expensive used amps of other brands on sale from customers who traded in these amps for a Deja Vu 45 or 2a3 or 300B amp.
Getting back to the Deja Vu pushpull amps, these were built mostly with somewhat difficult to find vintage output transfomers. Mine have Acrosound TO-330 transformers (ultralinear transformers, but with the feedback loops not used because the tubes are triodes). I think others were built with Chicago transformers as well. I don't use this amp any more, preferring my current 2a3 SET amp, but, that amp costs many multiples of the Deja Vu amp (now on loan to a friend). The store often had some very expensive used amps of other brands on sale from customers who traded in these amps for a Deja Vu 45 or 2a3 or 300B amp.