Any brand 5AR4 vs Sylvania 5V4GA?

[BmWr75]

There is another thread active now on 5AR4 rectifiers. @kvfly shared It's been said many times that the "military" 5V4GA made my Sylvania or Phillips ECG is probably their 5AR4 relabeled for the military since it would be drop in and heavier duty than the 5V4GT.

Post in thread '5AR4 questions'

Feb 24, 2026

BTW... if you need a new GZ34/5AR4 and NOS Mullard or Dutch Amperex tubes are too rich, look for a good NOS GE or Sylvania 5AR4. They are as reliable as the European GZ34s.

It's been said many times that the "military" 5V4GA made my Sylvania is probably their 5AR4 relabeled for the military since it would be drop in and heavier duty than the 5V4GT. I have a few and they have the same voltage drop as a 5AR4 which is less than a traditional 5V4GT. Note also that a 5U4G etc. is NOT a good sub for the GZ34/5AR4 because its filament requires 3 amps, vs the 5AR4 1.9 amps.

Stand by...

• kvflyer

• 

This put me on the hunt for some Sylvania/Phillips ECG 5V4GA rectifiers. Phillips ECG branded are selling for as much or more than Mullard 5AR4s these days on fleabay. So took a chance on some Sylvania 5V4GAs. Here are the test results of three of them compared to Amperex and Mullard 5AR4s. My Amplitrex tester doesn't have a 5V4GA test mode, so tested them as 5AR4s.

Pictures comparing a Sylvania 5V4GA to an RCA branded Mullard 5AR4 also attached. All four sides shown. Construction looks pretty different to my eyes.

Thoughts on the Sylvanias?

 

[whoaru99]

Unless I'm missing something, they don't appear physically nor test wise that they are 5AR4-like guts.

 

[Mr Boochie]

These are both 5V4GA. One is a big bottle Sylvania tube, and the other is a usual glass envelope, RCA.

As far as I know, only the Philips-ECG 5V4GA MIL SPEC tubes have the 5AR4 guts.

Everyone knows about this now, so finding any cheap NOS Philips ECG rectifiers will be difficult. However, in my experience, the Philips-ECG is just as good as the Sylvania (yellow label) 5AR4.

 

[BmWr75]

Unless I'm missing something, they don't appear physically nor test wise that they are 5AR4-like guts.

Agreed, like I said, could not find any reasonably priced Phillips ECG 5V4GAs for sale. So took a chance on these Sylvanias since they were inexpensive ($20 each delivered).

 

[Mr Boochie]

Agreed, like I said, could not find any reasonably priced Phillips ECG 5V4GAs for sale. So took a chance on these Sylvanias since they were inexpensive ($20 each delivered).

They are true 5V4GAs. You can't use them in a circuit that needs a 5AR4.

There are no Sylvania 5AR4 tubes labeled "5V4GA." Only Philips-ECG mil-specs.

 

[gadget73]

Agree about the higher forward drop and smaller structure implying lower current capacity.

All depends what you need it to do though. If the application is within the 5V4's limits its a perfectly fine tube. So in some circuits it *might* sub, but certainly not all. I've considered swapping the 5Y3 that runs the screen supply in my Rauland amps for 5V4. It would bump the screen voltage a little, but the slower warm up would ensure that the screen doesn't go positive before the plates do. 5Y3 is good for 125mA and a 5V4 is good for 175.

 

[BmWr75]

These are both 5V4GA. One is a big bottle Sylvania tube, and the other is a usual glass envelope, RCA.

As far as I know, only the Philips-ECG 5V4GA MIL SPEC tubes have the 5AR4 guts.

Everyone knows about this now, so finding any cheap NOS Philips ECG rectifiers will be difficult. However, in my experience, the Philips-ECG is just as good as the Sylvania (yellow label) 5AR4.

I'm not tube expert, but here is the RCA branded Mullard 5AR4 you say is a 5V4GA compared to a Mullard 5AR4 (on the left) purchased from @Kegger many years ago. Construction between the two looks close, if not identical to me.

 

[Mr Boochie]

I'm not tube expert, but here is the RCA branded Mullard 5AR4 you say is a 5V4GA compared to a Mullard 5AR4 (on the left) purchased from @Kegger many years ago. Construction between the two looks close, if not identical to me.

Sorry, yes, these are Mullard GZ34-made tubes. Check the bottom of the tube for the typical Philips/Mullard etching.

 

[gadget73]

I have some US-made 5AR4, its in a fatter bottle than the Mullard ones. Can't recall offhand if its GE or Sylvania though. For some reason I'm thinking GE branding, Sylvania production? Or maybe I have that backwards.

I have a Mullard-made one with odd branding too, I want to say is "6202 Valve" or something like that. Apparently they were a British reseller like National Union or ElMenco. Got it NOS in the box. Dog ate the box unfortunately, but the tube is in my Fisher 600.

 

[Tom Bavis]

The Sylvania-made 5AR4s I've seen are the fattest; GEs are like Mullard. I've seen RCA 5AR4s made by Mullard mostly, but also GE and Sylvania.

 

[Mr Boochie]

I have some US-made 5AR4, its in a fatter bottle than the Mullard ones. Can't recall offhand if its GE or Sylvania though. For some reason I'm thinking GE branding, Sylvania production? Or maybe I have that backwards.

If they have an exposed copper edge, they are the GREAT GE (Owensboro-made) 5AR4.

 

[gadget73]

I think it does, but the bottle is more 5U4GB diameter x 5Y3GT height.

 

[Dswankey]

Sorry, yes, these are Mullard GZ34-made tubes. Check the bottom of the tube for the typical Philips/Mullard etching.

I spy

f32
B5E

 

[Mr Boochie]

I think it does, but the bottle is more 5U4GB diameter x 5Y3GT height.

Sylvania 5AR4 tubes are in taller and fatter bottles than the GE 5AR4s.

 

[gadget73]

Visually that Sylvania looks like what I remember. Its somewhere in a caddy and I haven't dug it out in a while.

 

[Mr Boochie]

Visually that Sylvania looks like what I remember. Its somewhere in a caddy and I haven't dug it out in a while.

Those are great tubes. As good as any Mullard (UK).