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5AR4 vs 5V4GA

10/31/2000 6:34 AM
5AR4 vs 5V4GA
Could I replace the 5AR4 with 5V4GAs in a bogen pa amp? The amp uses 3 5AR4s it the one with two 7025 power tubes. PB.
10/31/2000 8:15 PM

are you telling me that it uses three rectifiers for only two power tubes. That cant be possible.
10/31/2000 8:28 PM

and the power tubes are probably 7027. Hopefully you've got some left over 5AR4's(and they're Mullards).
10/31/2000 8:32 PM
the 100watt chassis i turned into my latest project had 2gz34's and an ez81 rectifier for just two power tubes!
10/31/2000 10:22 PM
Ray Ivers

The 5V4GA is rated at 175 mA continuous current capacity, not the 250 mA of the 5AR4/GZ34. It sounds like your amp may have multiple rectifiers for plate/screen/bias(?) supplies. You're not taking a chance with drawing too much rectifier heater current - the 5V4's draw 2 amps like the 5AR4's do - but you may encounter excessive B+ sag and reduced rectifier life, if not outright failure. I would stick with 5AR4's in all the rectifier positions, at least until you can find out what each 5AR4 does.  
Ray Ivers
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