5AR4 rectifier tubes - Chinese or Russian?

A third knod to Mullard / Blackburn NOS. Expensive, but worth it and will likely last long. Buy from a reputable seller, like Upscale, Vintage or The Tube Store. A rebranded Mullard should be $75-85/tube last time I checked and could be branded as Amperex, RCA, GE or some other companies that had Mullard make their tubes. Mullard branded tubes (labeled "Mullard") will run more expensive so I'd look for the rebranded ones from a reliable seller. Same tube with a different label. Best versions of the 5AR4 are actually metal-based versions but those will cost your first-born, and I'm not sure are worth the added premium (I guess that depends on how much you love your child). If you'd prefer to hang onto your heir apparent you could seek out an NOS 22S22C substitute, for which your soul may be adequate payment. Worth it for the extra bottom end resolution and bragging rights.

If the Mullards are beyond what you'd like to spend, you might look into those Japanese Mullard copies. I've no personal experience with them, but if Kevin gives them his endorsement- that speaks volumes.(http://www.upscaleaudio.com/Japanese-5AR4_p_75.html) I DO know that the Japanese are positively anal when it comes to quality control and consistancy in manufacturing practices(diametrically opposed to the chinese mindset). You might contact him, and ask his opinion with regard to their use in your unit. He's always happy to assist a fellow music lover and tubeophile. It's a shame he doesn't have any Mullard GZ34's(which would still be my #1 recommendation).

About 11 years ago I bought a boutique guitar amp--a Top Hat Club Deluxe, which is all tube PTP wired, and also used a GZ34/5AR4 rectifier. I decided to replace the Sovtek tubes and Chinese rectifier with new old stock US and European tubes. The NOS preamp and power amp tubes were affordable enough at the time (if you knew where to look), but all the US and European NOS rectifiers were well over $100. I decided to compromise and got an RCA-Japan 5AR4 for $25. I'm glad I did. Word from the vintage guitar gear enthusiasts was that a poorly made rectifier tube could kill your amp. My RCA-Japan has been exemplary. Its price sits on the low side between a Chinese tube and a US-Euro NOS, but its dependability is like the US-Euro NOS.

So to me, the Japanese tubes are worth the extra money over a Chinese tube for the peace of mind.

Buy a metal base gz34 and never look back.

Having a little trouble locating a matched pair of Mullard NOS or rebranded or even used testing new. I guess I'll be out of tunes for a while, unless I rotate in my old Marantz integrated amp in the meantime.

By the way, it seems that Upscales price on the Japanese tubes is $60 so if I could find Mullards new or used for 85 -100 each that'll be the way I go.

Thanks for everyone's input.

By the way, Kevin Deal said he'd spend his money on the 12AU7s and 12AX7s and not worry about expensive rectifiers,

Eric