[ltr317]

I recently found a pair of Allegro 12ax7 tubes in my closet. I never heard of the company, was wondering if another manufacturer made them for Allegro. Anyone familiar with these tubes?

[thorman]

I remember seeing these on audioshopper.com...They were on there for quite awhile.I believe it was a west cost audio shop that was selling them..If you check the web site you may find some info there............

[Mike B.]

I bought a bunch back in the 1980's. They are sand blasted, so the glass is opaque. Decent sounding tube. I imagine they are a selected production tube from that period?

[ltr317]

I bought a bunch back in the 1980's. They are sand blasted, so the glass is opaque. Decent sounding tube. I imagine they are a selected production tube from that period?

Someone told me they may be rebranded Westinghouse.  What does sand blasting do to the tube?

[Mike B.]

The only thing sandblasting does is opaque the glass and obscure view of the inside. Many tube experts could easily tell who made the tube if they could see inside.