Rectifier tube vertical mounting requirement

CZ4A

Active Member
I am in the process of recapping and restoring my Sano 16WR guitar amp, which mounts its tubes horizontally. I am also adding the tube rectifier back to it in place of some diodes. When looking at datasheets for the 5Y3 and 5T4, I noticed they say that the tubes should be mounted vertically, or horizontally only if the #2 and #4 pins are in a vertical plane. What is the reason for this, and would mounting the rectifier tube horizontally with #2 and #4 in a horizontal plane cause any issues?
 
I am in the process of recapping and restoring my Sano 16WR guitar amp, which mounts its tubes horizontally. I am also adding the tube rectifier back to it in place of some diodes. When looking at datasheets for the 5Y3 and 5T4, I noticed they say that the tubes should be mounted vertically, or horizontally only if the #2 and #4 pins are in a vertical plane. What is the reason for this, and would mounting the rectifier tube horizontally with #2 and #4 in a horizontal plane cause any issues?

Filament sag, if it's oriented correctly, the filament will sag in the direction where its least likely to touch the plates.

I say if it was made that way from the factory, just leave it as is. Tubes were improved over time, and probably the later ones didn't have the issue to the point it ever caused problems.
 
Filament sag, if it's oriented correctly, the filament will sag in the direction where its least likely to touch the plates.

I say if it was made that way from the factory, just leave it as is. Tubes were improved over time, and probably the later ones didn't have the issue to the point it ever caused problems.

That is the correct answer...
 
Thanks for the replies. If I can, I will try to mount the rectifier with the #2 and #4 pins in a vertical plane. If not, I'll just test the rectifier periodically.
 
Testing isn't the issue. If the filament sags and touches the plate, its a short and you can blow the power transformer. Fuse the B+ supply if you're going to do that. One from the center tap to chassis ground would be sufficient.

Personally I'd probably swap it for an indirect heat rectifier that doesn't care which direction it gets mounted just for insurance.
 
Thanks for the replies. If I can, I will try to mount the rectifier with the #2 and #4 pins in a vertical plane. If not, I'll just test the rectifier periodically.
You can have your cake and eat it too. The 6087 is a 5y3 which is indirectly heated cathode. Although what is the big deal with mounting a tube socket that has pins 4 and 6 the filament pins (not 2 and 4) mounted in a vertical plane? I mean if you have to drill the mounting holes for the octal socket mark the 4 and 6 spot on the socket so that they are easily visible, then align them correctly and mark the mounting screw holes. And seriously, this kind of extra steps is wonderful brain training to keep those neurons firing.
 
for more genius points, L-bracket (assuming sufficient clearance in 3 planes) with male
socket adapter to the rectifier tube , wired to a standard socket for vertical tube
orientation.

then you can rock out the back of the pickup while off-roading in four feet
of powder going over a mogul...

enjoy the music
 
Max Sound ???

Use the 5Y3, because it has NO cathode, it is a directly heated rectifier tube, which will thus sound superior to a rectifier with a cathode.

As already suggested, implement an L bracket to mount it vertically. Tube needs 5 VAC at 2 Amps as I recall. Directly heated tubes, for amplification, or rectification, do sound better.

At 5 VAC 3 A., in lieu of a 5Y3, one might consider use of a heftier 5U4GB. JJ and Elecro Harmonix make such current-production rectifiers that sound good, the later after a 200 hour break in.

There are LIMITS to the amount of uF a tube rectifier wants to " see" as an input filter ( I always only use a L input ) , so please do consider that.

Dowto1000
 
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Would you care to share with us the technical reason for that statement please?


LOL, its not meant to be technical. You don't read this in a book. I don't really need to know WHY, just WHAT WORKS best, is OK for me.

Audio is done in two camps. By the book people, and listener people. The by the book people will NEVER EVER build a better sounding amp, than those who build by ear. I understand much of the technical, but build by ear.

There we have it, the BIG audio design "picture."

No offense is meant to anyone, what so ever.

In a good one or two Watt SE amp, listen to a indirectly heated rectifier tube, versus a directly heated 5U4GB ( EH or JJ ), and tell us what you hear.

" The proof of the pudding " is not in the recipe, but instead, " in the eating. "

Regards,


Dowto1000
 
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LOL, its not meant to be technical. You don't read this in a book. I don't really need to know WHY, just WHAT WORKS best, is OK for me.

Knowing the why is very important as you can relay that information to us so that you don't look so much like an audiophool trying to sell us snake oil.

Audio is done in two camps. By the book people, and listener people.

By the book people mostly do sensible amp designs that work and sound very good. Ask many on here that have tube amps such as Scott, Fisher, McIntosh, Heathkit ETC... and they will tell you how good they sound.

Listener people often build amps with lots of snake oil then claim it sounds so much better. Possibly in hopes they can justify how much $$$ they spent on that two watt single ended triode amp.

The by the book people will NEVER EVER build a better sounding amp, than those who build by ear. I understand much of the technical, but build by ear.

Tell that to the many people who bought or built excellent sounding amps that were by the book and they might laugh.

In a good one or two Watt SE amp, listen to a indirectly heated rectifier tube, versus a directly heated 5U4GB ( EH or JJ ), and tell us what you hear.

Single ended amps have several issues that were solved with push pull amps.

Far as tube rectifiers go the only thing that alters the sound is how much voltage the tube drops. If a particular brand of rectifier sounds different than another brand's tube of the same type (if that is even possible) then the tube is not to the spec of the tube type and should either be rejected as a defective tube or given a different tube number.



Sounds like time to swap out my flip flops for the hip waders.

Can you send a pair my way. It's getting pretty deep in here.
 
How about if you mount them at a 45 degree angle? ;-}

253031-eico_hf12_el84_6bq5_mono_amplifier.jpg


Eico for one did that to minimize case height ...

PS ... this one uses an EZ81 rectifier. Doesn't look like they paid any particular attention to pin orientation, so maybe it's a type specific kinda thang. Earlier suggestion about substitution might give you more design options.
 
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How about if you mount them at a 45 degree angle? ;-}

253031-eico_hf12_el84_6bq5_mono_amplifier.jpg


Eico for one did that to minimize case height ...

PS ... this one uses an EZ81 rectifier. Doesn't look like they paid any particular attention to pin orientation, so maybe it's a type specific kinda thang. Earlier suggestion about substitution might give you more design options.

BTW, the EZ81 is a cathode rectifier by the way. Somehow, I think that the engineers may, just may have known what they were doing....
 
Tube specs are very much based on dimensional tolerances. If a diode couldn't maintain the tolerance budget required to meet PIV spec when not oriented in a particular manner then that is why they add that note to the datasheet. Caveat emptor for those who deviate, and don't have a clear understanding of how to mitigate their risk.
 
By the book people mostly do sensible amp designs that work and sound very good. Ask many on here that have tube amps such as Scott, Fisher, McIntosh, Heathkit ETC... and they will tell you how good they sound.
I have over 30 vintage amps, Harman Kardon, McIntosh, Fisher, Scott, EICO, Dynaco, etc. And as good as they sound I found that my own custom made amps sound better. You might consider that all commercially available amps are built to a price point and a custom builder can build using similar components but to a higher performance level.

"Listener people often build amps with lots of snake oil then claim it sounds so much better. Possibly in hopes they can justify how much $$$ they spent on that two watt single ended triode amp. "
What is the basis for this statement. I have been associated with this hobby for over 20 years, looked at hundreds if not thousands of pictures of home made amps, and i have not seen any snake oil in any of them.
This statement is similar to Dowto's about audio being 2 camps, listener people and by the book people. The fact is the foundation for all vacuum tube amplifiers are based on seminal books by a few gifted individuals and whose ideas were later expanded and updated by others as new technology evolved. And just as it was back in the golden age of tube audio as it is still done now, and just as important as theory and engineering is the final "tweaking by ear" to achieve or verify a certain sound quality.

"Single ended amps have several issues that were solved with push pull amps."
Sure PP amps can produce more power and might test with lower distortion numbers. But if power and distortion numbers were the whole story then what do you say to those tens and hundreds of thousands of SE amp owners who have set aside their PP and feel that a SE amp has qualities that their other amp can not provide.
I think the point is that different people like different things for different reasons. And to say that one type of construction or mode is better than another just limits the options or variations that can be a better fit to one's particular situation vs. someone else's niche.

.[/QUOTE]
 
When I say snake oil I mean things that are ridiculously expensive with dubious claims.

Several websites sell that stuff so I can only assume people use them in builds.

I've seen some film caps and other parts on one particular audiophool type website and they are quite expensive with claims that most normal electronics techs know are BS.
 
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