Has anyone tried a 12AV7 in an Apex 460 (Alctron HST-11a?)

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Blue Jinn

Blue Jinn

Rider of the ARPocalypse
As opposed to 12AX7 (stock) 12AY7 (most common mod) 12AT7 etc?
 
I would think 12AV7's are hard to find, but AES has them for $5 which it an interesting experiment. Just go by the gain factor, but also consider the current capacity;
  1. 12AX7 = 100 (1mA Plate current)
  2. 12AT7 = 70 (10mA Plate current)
  3. 5751 = 70 (1mA Plate current)
  4. 12AU7 = 40 (10mA Plate current)
  5. 12AV7 = 40 (18mA Plate current!!!)
  6. 12AY7 = 40 (3mA Plate current)
Even though the 5751 has the same gain as a 12AT7, it can't handle the 12AT7's current. The 12AU7 can't take the 12AV7's current. What that does to the tone, I don't know, but it's cheap enough to try. My guess is that with big signals and transients, the Plate voltage sags enough that it may add an interesting compression all on it's own. I'd try it. The 12AV7 might have a lot more headroom with all that current capacity. My final guess is that you lose some gain, but get a lot more headroom.
 
I thought 12AU7 had a lot lower gain, along the line of 17. I haven't looked at the plate curves for any of these, just the gain factor. Mmmmh.
 
Oops, I messed up that one. Depending on the website or tube manual, the 12AU7 is 17 or 19 or 20. Not 40 as I spoke out of turn. :o Still, I'd try it for $5 and something to do on a lazy afternoon.
 
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