GZ34/5AR4 Rectifier Tube Brands?

[Fresh_Start]

Everybody has a favorite 12AX7, most guys like this or that 6V6/EL-84/etc. but I've never seen any discussion of rectifier tubes.

I need a GZ34/5AR4 rectifier tube for a Blackface Princeton Reverb clone. Choices so far seem to be Sovtek or JJ.

I know from experience that the Sovtek 5Y3GT simply isn't a real 5Y3GT (not enough voltage drop) but haven't seen anything bad about other Sovtek rectifier tubes.

I'd really appreciate any advice.

Chip

P.S. The search function here hasn't worked right for me for over a month.

 

[Dr.Mavashi]

Re: GZ34/5AR4 Rectifier Tube Brands?

I wish somebody could refer me to a link here that explains really well to somebody with absolute zero background in electornics what rectifier actually does, how does non-tube one effect the tone versus a tube rectifier and whether high end boutiques amps use those or if its more Mesa exclusive specialty. Thanks .......

 

[the guy who invented fire]

Re: GZ34/5AR4 Rectifier Tube Brands?

Dr.Mavashi: Let me see what I can dig up for you...

Chip, NOS GZ34's cost a ton right now..Im talking in excess of $125 each! I am running a Sovtek GZ34 in my brown Deluxe right now and have had no isseus with it.

 

[Fresh_Start]

Re: GZ34/5AR4 Rectifier Tube Brands?

Christian - thanks for the quick response.

Dr.M. - the rectifier converts A.C. (alternating current) into D.C. (direct current). Some tube amps use a tube diode, some use a semiconductor diode. SS amps always use semiconductor diodes.

SS diodes produce signifcantly more DC voltage from a given AC voltage than a tube rectifier. Also, a tube rectifier "sags". When the amp demands a jump in current, it takes the tube some measurable time to ramp up to that current demand. SS diodes react almost immediately, making the amp "stiffer". Like when you slam a power chord, the rectifier tube can't respond immediately to the power tubes' demand for more current.

Hmmm... that probably doesn't help much. I'm having trouble finding words to better describe "sag". Hopefully someone else can give you a better player's perspective.

Oh, there are "metal rectifiers" or semiconductors that can be put into a tube socket. In general, that's a bad idea IMHO. Heat issues, voltages not right for the amp design, etc.

Chip

 

[Lewguitar]

Re: GZ34/5AR4 Rectifier Tube Brands?

Christian, did I send you a Sovtek Mullard to use in that amp? I like the Sovtek GZ34 that comes in the Mullard box. I use NOS Mullards and RCA myself...real ones. But the Sovtek version of the Mullard sounds pretty good too.

Lew

 

[Scott_F]

Re: GZ34/5AR4 Rectifier Tube Brands?

I've used a lot of JJ's with only one recorded failure I know of.

 

[Binnerscot]

Re: GZ34/5AR4 Rectifier Tube Brands?

I really like the JJs in Mesa amps. They seem to have the right amount of sag without feeling mushy. Kind of like sag with some bounce. They have been reliable for me for some time now.

 

[jeremy]

Re: GZ34/5AR4 Rectifier Tube Brands?

i use jj's and whatever ruby sells as its gz34

 

[Dr.Mavashi]

Re: GZ34/5AR4 Rectifier Tube Brands?

Fresh Start, thanks man but I am pretty un-electronic, AC vs. DC - I have no idea what that means. So I guess the whole messa thing is that they put two or three tubes to make the "rectumfrier" respond faster? Inst it just a gimmick then? Do rectifier tubes manipulate tone to the same extent as pre-amp tubes do? Dr.TGWIF calling Dr.TGWIF! Thanks dudes.

 

[the guy who invented fire]

Re: GZ34/5AR4 Rectifier Tube Brands?

Christian, did I send you a Sovtek Mullard to use in that amp? I like the Sovtek GZ34 that comes in the Mullard box. I use NOS Mullards and RCA myself...real ones. But the Sovtek version of the Mullard sounds pretty good too.

Lew

It's a Sovtek...it doesn't say Mullard anywhere on it, where is the tie in???

I like it so far but I've got a line of a few NOS RCA GZ34's I think Im gonna snag and try out...

 

[the guy who invented fire]

Re: GZ34/5AR4 Rectifier Tube Brands?

Fresh Start, thanks man but I am pretty un-electronic, AC vs. DC - I have no idea what that means. So I guess the whole messa thing is that they put two or three tubes to make the "rectumfrier" respond faster? Inst it just a gimmick then? Do rectifier tubes manipulate tone to the same extent as pre-amp tubes do? Dr.TGWIF calling Dr.TGWIF! Thanks dudes.

Rectifier tubes cn have an effect on the tone of an amp, and often do...it's just in a different way than you you'd be used to in dealing with pre and power tubes...

 

[kmcguitars]

Re: GZ34/5AR4 Rectifier Tube Brands?

I'm still scratching my head about the GZ34 vs. 5U4G over at Doug's board?
I'm using a 5U4G in my new Princeton build? I'm using a Weber PT. I always thought using a GZ34 in my Princeton would jack my plate voltage to the ceiling and burn up my PT. Now I don't know what to think.:eyecrazy: I've been running a 5U4GU in my 79' Princeton since I got it in 94'. Never any issue's with that amp?

 

[Fresh_Start]

Re: GZ34/5AR4 Rectifier Tube Brands?

Fresh Start, thanks man but I am pretty un-electronic, AC vs. DC - I have no idea what that means. So I guess the whole messa thing is that they put two or three tubes to make the "rectumfrier" respond faster? Inst it just a gimmick then? Do rectifier tubes manipulate tone to the same extent as pre-amp tubes do? Dr.TGWIF calling Dr.TGWIF! Thanks dudes.

The simplest way to describe a rectifier is to call it the first filter stage in the power rail. Alternating current (pulses of positive & negative voltages at 60 hz) comes out of the wall outlet. That needs to be filtered into nice, smooth direct current (same steady positive voltage all the time) before it goes to your power tubes & preamp tubes.

I'm not familiar with the Mesa "dual" or "triple" rectifier circuits and Schematic Heaven has gone AWOL. IIRC some of their amps allow you to switch between solid state rectification ("tight") and tube rectification ("loose"). That should produce a real difference in how the amp sounds and responds, especially if the voltages change when you change rectifiers. It could be a cool feature, depending on how it's executed in the amp's circuit.

In amps with four or more power tubes, having two rectifier tubes may be necessary or desireable to provide sufficient current for really high wattage (like 100 watts +). For solid state rectification, you can just buy silicon diodes with higher amp ratings. Despite all that, Mesa does broadcast some pretty thick B.S. in their marketing IMHO. I read their ad copy for the Blue Angel, then looked at the schematic. It does have a neat circuit to switch between two different tube types, but there's no magic genie in there

Hope this helps,

Chip

 

[ES350]

Re: GZ34/5AR4 Rectifier Tube Brands?

...watch the current draw as well; don't run 5U4s (3 amps) in an amp designed for 5AR4 or 5Y3 (2 amps)...

 

[Fresh_Start]

Re: GZ34/5AR4 Rectifier Tube Brands?

...watch the current draw as well; don't run 5U4s (3 amps) in an amp designed for 5AR4 or 5Y3 (2 amps)...

That's actually why I'm shopping for a GZ34! I'm building a Princeton Reverb and discovered too late that my PT is only rated for 2 amps on the 5 volt winding (rectifier heater) but the 5U4GB I bought needs 3 amps. (When I say "too late" at least that doesn't mean after powering up the amp and possibly frying the power transformer - just after buying tubes.)

Chip

 

[ES350]

Re: GZ34/5AR4 Rectifier Tube Brands?

Well, the schematic for a GZ34 equipped Princeton AA1164 shows 410 on the plates---otherwise a 5V4G (slow warmup like a GZ34, 2 amp pull, 25v drop@175 ma) might be an alternative, but only 375 VDC. I've run them in tweeds with 400+ on the plates no problem...might be worth a shot. Legend has it that some of the RCA branded 5V4GA are really 5AR4s anyway...

 

[jeremy]

Re: GZ34/5AR4 Rectifier Tube Brands?

i use a 5V4 in my tweed deluxe sometimes and i like the results. i keep a few 5ar4, 5v4, and 5y3 tubes around since they all draw the same, not necessairily interchangeable in all amps though.

should work ok in the princeton

 

[ES350]

Re: GZ34/5AR4 Rectifier Tube Brands?

Another one to consider for a tweed Deluxe or similar amps might be a 5R4; the big bottle version of a 5Y3...can be had pretty cheap these days.

 

[jeremy]

Re: GZ34/5AR4 Rectifier Tube Brands?

never seen one, thanks for the tip

 

[Lewguitar]

Re: GZ34/5AR4 Rectifier Tube Brands?

It's a Sovtek...it doesn't say Mullard anywhere on it, where is the tie in???

I like it so far but I've got a line of a few NOS RCA GZ34's I think Im gonna snag and try out...

I prefer NOS RCA and Mullards. As for the Sovtek Mullard...you're right. They're just good new Sovtek GZ34/5AR4 tubes. But they sound good...and the box is real purty! :1:Lew