Aric Audio Systems Unlimited Preamp

I'm very familiar with it as I had one for some years. I still have it actually, I have just moved on to his Special 6SN7 Linestage which is similar, except it's purity times 10. It now leads the charge and no one is looking back.

Hi Ray, I'm using a NOS Sylvania 5U4GB (Black Plates) which I have come to believe is a wonderful discovery as it transforms the whole presentation into something nearly magic. I don't know why. As far as the regulators go, truthfully, I haven't noticed a marked difference between any of the types I have tried. The rectifier tube seems to influence the delivery far more than do the regulators. My opinion only.

Thanks for the response tubepower. The Unlimited uses a 5AR4 rectifier. I'm wondering if that variation will yield similar results as the Sylvania 5U4??

Hey guys! @rocray , the 5U4GB (not 5U4 or 5U4G) can safely be used in the Unlimited as the first filter cap it requires can be no larger than 40uf, whereas the 5U4 is much lower (the Unlimited uses 33 uf). Using it will lower the B+ voltage just a bit, so just make sure the regulators light consistently. If you find they are going out, then use one OC3 and one OD3 when the 5U4GB is in place. I agree with Tube Power on his choice for a favorite 5U4GB. For 5AR4s I’ve only ever used new production- either the Sovtek, Tung Sol or Mullard reissues all sound really good! Best, Aric

Hi Aric. Thanks so much for the response and recommendations. It's awesome to have the manufacturer so easily accessible. What sonic differences can I expect by swapping in a 5U4GB?