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I just dropped a pair of WE 350B's into my Cortese about 3 weeks ago and am more than thrilled with the fantastic results. They continue to improve (did not think that to be possible) as they break in.
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I thought I had gotten as far as possible with improving the sound of my Cortese by tube rolling andwas quite happy, but I kept reading and re-reading all of the talk about how great and how expensive the 350's are. Finally, I found a pair of 350's on ebay at a relatively good price (still a killer), but it has been well worth the money spent.
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I replaced a pair of NOS Philips 1963 Miniwatt / Mullard EL37Âs with the WE 350BÂs and the improvement was startling. The EL37Âs had produced wonderful sound and I was quite content, but you know, the disease got me and I popped for the 350Âs  great move.
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I would highly recommend the EL 37Âs for the regulator position, but if you are in a position to pick up a good pair of WE 350BÂs, do it.
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Given that the 350Âs should last longer at the regulator position longer than I will on the planet, this should turn out to be one of my better aggressive decisions.
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I am thinking I can sell them to Bryan White in about 20 years and make a tidy profit.
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