Hey there,,, I know that an amp should take whatever is called for, but aren't 5Z4s, 5V4s & 5U4s similar? I know 5Y3x are at one end, w/5AR4s at the other electrical extreme, but don't those others sit in the middle & might have a different degree of sag, and may lend a different smoke-free flavors? IIRC, the U4's also are not a simple swap voltage wise....?
Thanks!
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5R4 RECTOS
Moderators: pompeiisneaks, Colossal
Re: 5R4 RECTOS
It seems you are starting to get serious about amp stuff. I suggest you'd benefit from something that helps you with tubes. I suggest that you get this: http://www.duncanamps.com/tdslpe/ the download link is at the bottom of the page,
or bookmark this page http://tdsl.duncanamps.com/tubesearch.php
Look at the tube date for each of the tubes you are asking about. See if you can figure this out.
or bookmark this page http://tdsl.duncanamps.com/tubesearch.php
Look at the tube date for each of the tubes you are asking about. See if you can figure this out.
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Stevem
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Re: 5R4 RECTOS
The heater current needed by the 5U4 precludes it from being used where a 5ar4, 5v4 and 5y3 was use in many amps, and I have over the years worked on many many Fender amps and a few others whose owner had a 5y3 or 5ar4 blow on them and in a pinch stuck in a 5u4 and slowly then burned up their amp's power transformer !
Also note that a 5y3, 5v4 and very close behind it a 5u4 take a full 1/2 second to recover from a hard sag condition.
In a true class A amp this means little to nothing, but in a class A/B amp do not be looking for good levels of punch if you're playing the amp loud enough to be getting the tube into a sag condition!
This condition however is great for sustaining notes during load enough slow blues playing where you have that 1/2 second or more inbetween notes.
Also note that a 5y3, 5v4 and very close behind it a 5u4 take a full 1/2 second to recover from a hard sag condition.
In a true class A amp this means little to nothing, but in a class A/B amp do not be looking for good levels of punch if you're playing the amp loud enough to be getting the tube into a sag condition!
This condition however is great for sustaining notes during load enough slow blues playing where you have that 1/2 second or more inbetween notes.
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
YES, PHIL_S,,, 5R4 RECTOS
Thanks for the advice & guidance. My tech is serious about this stuff, whereas I'm more curious,,, and I do not perform mods of any kind. I have lots if rectos & octals lying around, & while i know there are probably NO direct drop-ins for tubes, except for for the 12**7 family. And & know that different rectifiers, if acceptable to the circuit, can change the amp's attitude, albeit not greatly, being a recto. But I am curious about the 6SC,SN,SL,SJ7 family. With appropriate design tweaks, which of these octals share the same pinout, and could be subbed, w/o a total rewiring, if any....?? Thanks Phil,,, as I'm legally blind, it's often difficult to easily download & investigate these stats, which is why I come to this place, hoping for some quicker results.
Again, I don't do mods, & all I'm good for is a 3 prong cord, change out an old resistor or cap, install a fuse receptacle, & change tubes. With the octals, I'd like to know what subs are possible, even w/some rewiring, & what their gain factors are....
Basically, I'm having someone modify some 50/60's mono tube PA amps for guitar use, & was curious to know what tubes that I have in my best collection, can be swapped in for some better gain.
Thank you again, Kenny
Again, I don't do mods, & all I'm good for is a 3 prong cord, change out an old resistor or cap, install a fuse receptacle, & change tubes. With the octals, I'd like to know what subs are possible, even w/some rewiring, & what their gain factors are....
Basically, I'm having someone modify some 50/60's mono tube PA amps for guitar use, & was curious to know what tubes that I have in my best collection, can be swapped in for some better gain.
Thank you again, Kenny