Rectifier tubes, the hidden "sweetness" of electronic gear, vintage and new, guitar amps and stereo.

My Fisher 500 mono receiver uses a Fisher brand 5V4GA rectifier tube.

 

My Welborne Labs Laurel IIx 300B SETs use Mullard GZ37 rectifier tubes. I have quite a few GZ37s stashed away.

 

Dig the old "potato mashers".

Only have two amps that use tube rectifiers here, Heathkit WM4's with Sylvania 5V4GA's, and a Harman Kardon A224 integrated that has an old Mullard 5AR4 in it.

jeff

 

Dynaco Stereo 70-Mullard GZ 34
McIntosh MC-30-Mullard CV378
Fisher X100-some kinda 5AR4 (in storage)

 

See above? Mullard CV378?

 

A pair of VTA M-125 monoblocks with Mullard GZ37 rectifiers.
A Modwright SWL 9.0SE line stage pre-amp with Mullard GZ34.
A Modwright SWP 9.0SE phono pre-amp with Mullard GZ34.

 

ModWright LS 100
Phillips GZ34

 

Steve,

I use the Mullard CV378 for both my tube phono preamp and my 6L6 singled ended amp, that I built from scratch. The 5U4 also works really well in my amps, but the Mullard just adds a bit more of everything. However, as you said, the 5U4s are cheap at less than $20, while the Mullard is often north of $100.

 

My EICO HF-81 uses two EZ81 tubes. Amperex all the way.

 

Totally agree with you! Rectifier tubes have a huge impact on the sound. I was told by tube experts that "all rectifiers sound the same", but they absolutely do not.

 

Exactly! Amazing how some people who are supposed to be aware, are often clueless. Another so called know-it-all told me that once you are inside the amp chassis, it doesn't matter what wire you use. Huh?

In this hobby, it's worthwhile to discover things for yourself

 

I must have two or three dozen pieces of old test equipment, shortwave radios, a couple of AA5 radios that have tube rectifiers in them. All my hi-fi gear is solid state rectifier, except a singleton mono McIntosh two chassis really early amp. (Hasn't been run in two decades, except a five minute power up with a dummy load every couple of years.) I have one old guitar amp-a Vibro Champ-that was built as a tube rectifier unit and I converted it over to solid state and upped the filter cap ratings in the 1990s. I used dropping resistors and couldn't tell any difference in the sound at the time.

In push pull guitar amps, tube rectifiers contribute a sag that's tough (not impossible) to emulate with solid state. In hi-fi, I don't think tube rectifier sag does anyone any good. Not if you want fidelity.

 

My Manley Neo-Classic 300B Preamp - I dropped in some Mullard GZ-34's and never looked back...HUGE improvement !

 

Dynaco ST-70. Mullard GZ34 though I have tried 5U4GB in it that sounded really good.
Main is a home built single ended 45 amp using a Mullard GZ33 in the power supply.
Also have a rebuilt Bottlehead Foreplay II preamp (heavily modified) that uses a 6x4.

 

Dynaco Stereo 70 - Mullard GZ34
Dynaco MkIIIs - domestic-branded 5AR4s that look like UK GZ34s
Dynaco FM3 - domestic 6V4
Dynaco PAS-2 - domestic 12x4
Fender Deluxe-Amp - Amperex "Bugle Boy" GZ34
Fender Champ-Amp - RCA 5Y3
Vox Cambridge Reverb - Vox-branded Mullard EZ81
Marshall 1974 - Mazda EZ81

 

I always feel disappointed when I see a nice tube amp with no tube rectification.

 

I'd like to try one of these just for the heck of it but too $$

 

Allnic H3000 phono stage, using GZ 34 Mullard 'fat base' first series in the power supply chassis. I've rolled a number of different old rectifiers in it. Like the sound of this particular Mullard in the unit. ​

 

Totally disagree with you. Tube rectifiers, with a properly designed power supply and very high quality parts, sound fantastic. Indeed, I can't stand listening to SS rectification.