5e3 Build log

[Champ_49]

Hi all

Thought I'd post my 5E3 build log. Mainly. for my own reference. This is my second one. I just love the sound of this amp. Going to try now with a different grounding layout and go with metal films and mallory caps. Also using teflon wire.

[sluckey]

20AWG would have been fine. Guess what size the OT wires will probably be?

[bmccowan]

I'm wondering why you are having so much trouble soldering - you mention twice not getting the solder to flow/stick. I find that I do no need to sand/clean like you describe. Technique? The solder you are using? I see from the label that your solder has lower flux% than many, such as Kester 44.

[Champ_49]

20AWG would have been fine. Guess what size the OT wires will probably be?

Yup. True. There was an amp tech i knew that recommended to use some heavier gauge for speaker outs so i just got in the "habit" of using some heavier guages when i can.

Btw what guage do you use between the input jacks

[sluckey]

22

[sluckey]

Those have been sitting in a bin for a looooong time!

[Champ_49]

Those have been sitting in a bin for a looooong time!

 Yup. Exactly. Finally someone bought em (me). Maybe I got some NOS vintage jacks for a good price ;) I guess these longer bushing jacks aren't that popular.  I got these because the bushing will go through two washers, the chassis plus an additional faceplate.

The got the washers to isolate the jacks from ground.

[bmccowan]

Yes I see - special multi-color jacks I guess you would need to clean them up pretty good. I was thinking of using some thick black plexiglas for a faceplate - I guess those would be the ticket for that.

[sluckey]

Probably too late now, but after shining up those jacks I would put a dab of flux on each solder lug and tin them lightly. Then you can solder wires, etc. to the lugs even easier than soldering to new shiny jacks.

[bmccowan]

Sluckey, when working on old amps, its the tube sockets that sometimes give me that problem. I usually try to get in there with a little Dremel wire brush after I've removed the old leads and solder. it would seem tinning them like you just suggested would be a help?

[Champ_49]

Yes I see - special multi-color jacks I guess you would need to clean them up pretty good. I was thinking of using some thick black plexiglas for a faceplate - I guess those would be the ticket for that.

I actually like the hue. Gives it that old vintage vibe. But I need an amp that works.
 

[Champ_49]

Probably too late now, but after shining up those jacks I would put a dab of flux on each solder lug and tin them lightly. Then you can solder wires, etc. to the lugs even easier than soldering to new shiny jacks.

I think I will redo these. Just because i realized the leads that connect the jacks may be too thin. I used the small tiny leads from the some half watt resistors.  I know it may not be an issue in terms of sound but a bit worried mechanically. After repetitive plug ins and outs the tiny solid cores may break if and when the jacks come loose. I have a full bottle of flux paste waiting for me :)

[Champ_49]

Sluckey, when working on old amps, its the tube sockets that sometimes give me that problem. I usually try to get in there with a little Dremel wire brush after I've removed the old leads and solder. it would seem tinning them like you just suggested would be a help?

I usually use the Belton tubes. Never had a problem soldering to those. Which ones do you use Mccowen?

[bmccowan]

I'm referring to soldering to old sockets when I'm repairing/rebuilding old amps. Many of those are true point to point, so I'm removing leads from sockets, cleaning them up and soldering in new leads. For new builds I use Beltons or those ceramic ones that Doug sells.

[bmccowan]

Oh and I also just used some of those Celatex octal sockets - seem fine. No problem soldering to any of the new ones - just the old ones after I've tortured them getting the old leads off!

[Champ_49]

I'm referring to soldering to old sockets when I'm repairing/rebuilding old amps. Many of those are true point to point, so I'm removing leads from sockets, cleaning them up and soldering in new leads. For new builds I use Beltons or those ceramic ones that Doug sells.

Gotcha.
For the jacks i wrapped 400 grit sandpaper around a nail filer and used that. I will need to buy some Popsicles today for a nice refreshment :) Maybe a chopstick would work too.

[Champ_49]

Oh and I also just used some of those Celatex octal sockets - seem fine. No problem soldering to any of the new ones - just the old ones after I've tortured them getting the old leads off!

Getting leads off can be a pain especially with the stranded wire. I usually use a solder braid to suck as much solder off first. Then heat it up a bit and wiggle the lead until it comes loose from the remaining solder. Then just pull it out in one piece.

[bmccowan]

I typically do the same/similar - get rid of as much solder as possible first. But with amps from the 40s/50s the leads on resisters and caps were much heavier gauge than used today, so it can be a struggle to unwrap the leads from the socket tabs. I often try to carefully snip part of the lead wrap to help free them.

[Champ_49]

I typically do the same/similar - get rid of as much solder as possible first. But with amps from the 40s/50s the leads on resisters and caps were much heavier gauge than used today, so it can be a struggle to unwrap the leads from the socket tabs. I often try to carefully snip part of the lead wrap to help free them.

Yup. Especially with a good mechanical wrap on heavier gauge solid core wire its hard to take it out. With strands its just a pain too when there are small pieces of the wire all over the place but with those i manage to pull it out slowly since the strands are thin and spread out. I also snip it carefully after almost all the solder is off. Then i just take it out in pieces.  But yeah you gotta be careful not to snip parts of the socket tab. For solid core as long as i get a part of the lead a bit far from the tab then i snip it right there.

[bmccowan]

But yeah you gotta be careful not to snip parts of the socket tab.

Yup done that more than once. That's when I started wearing my reading glasses to work on amps.

[sluckey]

Mineral spirits is very good at cleaning up rosin. Much better than alcohol.

[Champ_49]

Mineral spirits is very good at cleaning up rosin. Much better than alcohol.

Thanks Sluckey.  I will try that. It wasn't easy using the alcohol to clean it.

[vampwizzard]

looking good!

[Champ_49]

looking good!

Thank you Vampwizard!

[sluckey]

I am trying something different. Isolating the pots from the chassis by using the shoulder bushings.

Totally wasted effort.

[bmccowan]

Totally wasted effort

Don't sugar coat it like that kid.
Seriously though, it seems like there has been a lot of "overreach" lately on build techniques. Maybe it's Covid fatigue?

[Champ_49]

I am trying something different. Isolating the pots from the chassis by using the shoulder bushings.

Totally wasted effort.

Was ready for someone to say this. Why? Have you tried it?

[sluckey]

Don't have to try it. It's pure nonsense. Kinda like "The leads are not straight but bent at two places to allow slight relief when components expand and contract due to heat." or your low gain/sustain PEC pots. Sorry buddy. I ain't buying any of it. I spoke up hoping to prevent anyone else reading this from believing it.

[Champ_49]

Don't have to try it. It's pure nonsense. Kinda like "The leads are not straight but bent at two places to allow slight relief when components expand and contract due to heat." or your low gain/sustain PEC pots. Sorry buddy. I ain't buying any of it. I spoke up hoping to prevent anyone else reading this from believing it.

Hey man. No need to get worked up about it calling it nonense. A builder can build however way he wants. This is based on what ive read and i am just trying it. One ground point to the chassis for the circuit. Not nonsense because you did not take the time to build it like this yourself. Just like a star ground with everything at one point will introduce random grounding. A brass plate will introduce random grounding.

I have tried the pec pots for the gain pot on me last two builds and yes there was less gain. I swapped out the alpha and ab'd it several times. That is why i said anomaly.  It doesnt make sense which is why I ab'd it to believe it, but yeah it did my friend.  Unless you have tried it yourself don't go around saying its nonsense. Vague statements without trying it yourself. Thats nonsense and ignorant.  Thanks for your answer but no thanks. I know you are a moderator and everyone knows you here but I really just came here to show my build and keep a journal for myself. Did no post here to get negative comments to "call me out". I am stating exactly what i observed.

[sluckey]

It doesnt make sense

Then it's nonsense. Think about it.

I remember you discussion "Am done with PEC for good." from 2015. Didn't make sense then either. But that's most likely because you didn't know what gain is. It's all opinion. My opinion is based on in-depth edcuation/training and 45 years career working with sophisticated electronics. The three issues I called you on are based on internet BS. You wasted a lot of effort and time and now I'm doing the same by continuing this discussion, so I'll just shut up.

Whether you appreciate my viewpoint or not, I felt I needed to get it out there. Maybe someone else will.

[Champ_49]

It doesnt make sense

Then it's nonsense. Think about it.

I remember you discussion "Am done with PEC for good." from 2015. Didn't make sense then either. But that's most likely because you didn't know what gain is. It's all opinion. My opinion is based on in-depth edcuation/training and 45 years career working with sophisticated electronics. The three issues I called you on are based on internet BS. You wasted a lot of effort and time and now I'm doing the same by continuing this discussion, so I'll just shut up.

Whether you appreciate my viewpoint or not, I felt I needed to get it out there. Maybe someone else will.

My observation was not nonsense. Just stating what i observed. In fact i wish it was nonsense. I talked with you about it before.  Seemed a bit more reasonable then. For someone to call me out based on what i observed so others wont believe it..

But yeah.. the pots don't ground the circuit so it was some extra work.  But hey I had some time on my hands so why not ;)

 For the input jacks.  I would say they do ground the circuit at multiple points so I used shoulder washers on those.

[bmccowan]

Whether you appreciate my viewpoint or not, I felt I needed to get it out there. Maybe someone else will.

I do, and I'm sure many others do. I've built and rebuilt a lot of amps, but I keep learning things from Sluckey, PRR, Tubenit, and the other moderators. The great thing about internet forums is that they allow anyone to post anything. It's also a challenging thing. As far as I'm concerned its the moderators' job to challenge information that they believe to misleading, nonsensical, or in some cases wrong (and to delete political commentary from people like me!) As you said Champ, you can build how you want, but you shouldn't expect the moderators to not do their jobs. Sometimes Sluckey is pretty direct. But take a look at how many times he has patiently walked novices through a project step-by-step. He's earned the right.

[Champ_49]

Whether you appreciate my viewpoint or not, I felt I needed to get it out there. Maybe someone else will.

I do, and I'm sure many others do. I've built and rebuilt a lot of amps, but I keep learning things from Sluckey, PRR, Tubenit, and the other moderators. The great thing about internet forums is that they allow anyone to post anything. It's also a challenging thing. As far as I'm concerned its the moderators' job to challenge information that they believe to misleading, nonsensical, or in some cases wrong (and to delete political commentary from people like me!) As you said Champ, you can build how you want, but you shouldn't expect the moderators to not do their jobs. Sometimes Sluckey is pretty direct. But take a look at how many times he has patiently walked novices through a project step-by-step. He's earned the right.

I will keep bullding my amp. I am having a blast as i always am building them. In fact i have been on this forum and sluckey has helped me as well when i started. Yup the shoulder bushings on the pots was overkill and yeah it wont make a difference but i dont regret it. It was still fun while i did it ;)

As for the pec pots  I was stating what i observed and so have others about the pec pots. This was on a jcm800 build awhile back in which i added an extra gain stage.  With that kind of amp it is noticeable. On the stock jcm800 build i noticed it as well.
It just didn't sit well with me to say it was my imagination or nonsense when in fact i talked about this on a whole thread awhile back and have read this on other forums from other builders. Like I stated.. an anomoly which i couldn't explain. Try this on a stock jcm800 as a gain knob and then you can make your own conclusions. I really wanted to know what was going on awhile back and wished someone tried what i tried.

I am also weary of "snake oil". I don't use sozo caps thinking they will make the difference and magically make my amp sound amazing.  I use regular mallory or orange drops.  Its the circuit design, layout, soldering, proper lead dress, etc that really make the difference.

 I bent the leads like I did because the 5e3 can get quite hot so it allows for expansion and on contraction relief as i read on here
 Yeah it might be overkill but it made sense to me.

https://robrobinette.com/How_To_Build_a_Tube_Amp.htm

If i am not welcome here I can gladly leave or get kicked out. and build it alone and have fun building it.. it is for me still a hobby..without the extra judgements and accusations of being misleading.  Again what sluckey stated are opinions/viewpoints not facts. And everyone is entitled to it. But calling out someone else as misleading is a bit too much.  If its dangerous yeah call it out.

 This is one reason initially i was asking myself if i should display my work on a forum or not.

[bmccowan]

If i am not welcome here I can gladly leave and build it alone and have fun building it.. it is for me still a hobby..without the extra judgements and accusations of being misleading.  This is one reason initially i was asking myself if i should display my work on a forum or not.

I suspect you are very welcome here - I and others enjoy reading about your projects. But I also expect honest feedback on what I post. Just recently I was informed that the way I handled re-soldering eyelets when replacing components on a Fender style eyelet board was "bad practice." That person was not telling me what to do, just expressing an opinion. I can do with it what I want.
I say - carry on as you see fit.

[Champ_49]

If i am not welcome here I can gladly leave and build it alone and have fun building it.. it is for me still a hobby..without the extra judgements and accusations of being misleading.  This is one reason initially i was asking myself if i should display my work on a forum or not.

I suspect you are very welcome here - I and others enjoy reading about your projects. But I also expect honest feedback on what I post. Just recently I was informed that the way I handled re-soldering eyelets when replacing components on a Fender style eyelet board was "bad practice." That person was not telling me what to do, just expressing an opinion. I can do with it what I want.
I say - carry on as you see fit.

Thanks Mccowen. Yeah you're right. I do think honest feedback is very helpful. And in fact welcome and appreciate it as it could help avoid real headaches later. But.. its always helpful to know why. Not just "this is the way you do it or not do it". A basic explanation as to why anybody has an opinion or viewpoint would be more helpful to someone else than just saying this is wrong. For example the bending of the leads at two points makes sense to me. As i have stated why this makes sense to me. If it doesn't make sense to you and you want to call it out, call it out but with an explanation and to why it doesnt work. Otherwise best not to call it out. Blank statements like "nonsense" with no explanation can be misleading as well causing confusion to the reader and detract away from a very viable method.

I was criticized alot when i first started building. Showed it to a very reputable amp tech where i live in Canada and he ripped me pretty bad. So bad with absolutely no sugar coating. But i really cleaned up on soldering properly and make sure all leads are mechanically connected as well as proper guage wires to use etc.. from that experience i learned alot and that helped me the most if anything. Initially he was pissed at how bad my build was but eventually walked me through the build. I've had my fair share of criticism and learned from that more than anything.

[sluckey]

Champ_49, I want to apologize for my responses above. To just say "totally wasted effort" was not polite. I could have chosen my words more carefully and offered a reason for my opinion. And then to bring up the other issues I had with what you said about bending leads and low gain pots was uncalled for. I am sorry.

I'd like to try to explain my view. I consider insulating the pots from chassis a bad idea. When the pots are connected to chassis the pot body acts as a shield around the resistor element. Kinda like using shielded cable for sensitive areas. When you remove that ground connection to the pot body, you lose that shield, and the pot body can now act as an antennae to allow all kinds of radiated electrical interference a chance to get to your signal that's inside the pot. And if you are fond of metal knobs (as I am) it's even worse because when you touch the knob, all that radiated electrical interference that your body picks up is also fed to the pot body. The chance of this stuff coupling into your signal through the pot body is increased. Now this may or may not be an issue, but when near fluorescent lighting there is a LOT of crap in the air. So, why tempt Murphy? Ground the pot body to provide the shield.

As for putting relief bends in component leads, I'm all for that. NASA required stress relief bends when mounting components. They even have a lengthy discussion about it in their soldering manual. But the stress relief bends are required to prevent component or solder connection failure due to mechanical stress. It's not done to protect against component expansion/compression due to heat. If you got that kind of heat inside an amp you need to find out why.

As for PEC pots having lower gain, you say yes, I say no. We had that discussion 5 years ago. We disagree. That's OK.

I usually speak in a very plain, to the point manner. And that is often hurtful to people. I'll work on my manners.

Peace... Steve

[Champ_49]

Champ_49, I want to apologize for my responses above. To just say "totally wasted effort" was not polite. I could have chosen my words more carefully and offered a reason for my opinion. And then to bring up the other issues I had with what you said about bending leads and low gain pots was uncalled for. I am sorry.

I'd like to try to explain my view. I consider insulating the pots from chassis a bad idea. When the pots are connected to chassis the pot body acts as a shield around the resistor element. Kinda like using shielded cable for sensitive areas. When you remove that ground connection to the pot body, you lose that shield, and the pot body can now act as an antennae to allow all kinds of radiated electrical interference a chance to get to your signal that's inside the pot. And if you are fond of metal knobs (as I am) it's even worse because when you touch the knob, all that radiated electrical interference that your body picks up is also fed to the pot body. The chance of this stuff coupling into your signal through the pot body is increased. Now this may or may not be an issue, but when near fluorescent lighting there is a LOT of crap in the air. So, why tempt Murphy? Ground the pot body to provide the shield.

As for putting relief bends in component leads, I'm all for that. NASA required stress relief bends when mounting components. They even have a lengthy discussion about it in their soldering manual. But the stress relief bends are required to prevent component or solder connection failure due to mechanical stress. It's not done to protect against component expansion/compression due to heat. If you got that kind of heat inside an amp you need to find out why.

As for PEC pots having lower gain, you say yes, I say no. We had that discussion 5 years ago. We disagree. That's OK.

I usually speak in a very plain, to the point manner. And that is often hurtful to people. I'll work on my manners.

Peace... Steve

Thank you Sluckey.  I apologize as well for my manner in tone. I just wanted an explanation. That was all. And the explanation you gave me above was very helpful and makes alot of sense now. I will in fact take the shoulder insulation off the pots now as how you explained it makes total sense now and. And thank you for pointing that out as it will prevent headaches later on down the road.  Also about the leads being bent at two places was mentioned in robinette's site and i was just basing it on what he said about temperature cycles that could cause the contraction and expansion of components.

 For me it was not the inside of the amp that got hot but i put it in cabinet and closed the power tubes in so i guess the heat did not find a way to escape and the chassis got hot after long hours of playing.

As for the PEC pots yes lets just agree to disagree. :)

[Champ_49]

If anyone wants some additional info on this here are a couple of links i found which may or may not but helpful and might be a bit overkill for an amp. But still informative.

https://workmanship.nasa.gov/lib/insp/2%20books/links/sections/601%20General%20Requirements.html

https://robrobinette.com/How_To_Build_a_Tube_Amp.htm

[bmccowan]

When the pots are connected to chassis the pot body acts as a shield around the resistor element

And to an earlier point - look at that, I just learned something new again! That's what makes this forum so valuable.

[PRR]

I dug 70 feet of hard rooty clay to replace my sewer line. It had been ripped-apart, probably by thermal stresses. Maine has weeks near zero F and a day over 90F, every year. That's over an inch of thermal change. If you lay plastic pipe dead-straight it will find a place to break. The official guideline is to zig-zag a couple inches at every 10 foot joint.

I'm dubious about resistors and turrets being SO stiff and straight that reasonable temperature could pull them apart. Un-reasonable temperature is bad even before thermal strain.

[Champ_49]

I dug 70 feet of hard rooty clay to replace my sewer line. It had been ripped-apart, probably by thermal stresses. Maine has weeks near zero F and a day over 90F, every year. That's over an inch of thermal change. If you lay plastic pipe dead-straight it will find a place to break. The official guideline is to zig-zag a couple inches at every 10 foot joint.

I'm dubious about resistors and turrets being SO stiff and straight that reasonable temperature could pull them apart. Un-reasonable temperature is bad even before thermal strain.

Well I like to add some margin of error for my builds when possible. Although it could be overkill for some. It doesnt hurt. Now if those bent leads could cause issues then I wouldn't. If something were in fact wired wrong and caused excessive heat then that extra bend could save me from replacing them.

[Champ_49]

Probably too late now, but after shining up those jacks I would put a dab of flux on each solder lug and tin them lightly. Then you can solder wires, etc. to the lugs even easier than soldering to new shiny jacks.

Sluckey thanks for that tip. I missed that message since was a bit over my head. That would definitely help and I will try that next time.

[DummyLoad]

Another strangr anomoly with these pots is that they in fact reduce gain on my higher gain amps. I tried this several times and they do.

what a load of pure BS. NOT fact.

prove it.

--pete

[Champ_49]

Another strangr anomoly with these pots is that they in fact reduce gain on my higher gain amps. I tried this several times and they do.

what a load of pure BS. NOT fact.

prove it.


--pete


I did not say it was fact. The fact is that is what i observed.  Why does that make you so angry?

I would like to know if anyone else had tried this and noticed anything..would like to know too it doesn't make sense. I am using these pots on my build and I like how they are built and would like to use them.. I think we are all old enough to discuss things in a polite way by now.

Wow. You cant even state an observation here without someone getting upset or offended. Sad man.

[DummyLoad]

you assume i'm angry. not so. just mildly amused.   


--pete

[Champ_49]

you assume i'm angry. not so. just mildly amused.   


--pete

Misunderstanding then. Hard to tell with text. But can't picture you calling my observation bs with an amused look. You do sound upset or offended though for whatever reason. No offense.

[shooter]

ah the world of text without context 

I would love a side-by-side scope shot on the pot/gain thing though.  even easier would be a slow roll video of a meter as you dial the different pots real slow.  A defective part might cause unwanted "change"

[sluckey]

Here's all the proof you guys need...

     https://el34world.com/Forum/index.php?topic=19402.msg200627#msg200627

[Champ_49]

ah the world of text without context 

I would love a side-by-side scope shot on the pot/gain thing though.  even easier would be a slow roll video of a meter as you dial the different pots real slow.  A defective part might cause unwanted "change"

Yes. I wish i could do that. Unfortunately i already built my amp and don't want to go in and take it apart now.

I am putting this more in layman's terms without getting too much into technicality  because thats not the point.
Simply put..
PEC pot with preamp volume of jcm800 all the way up with all other being constant is like the alpha pot at 6 or 7. That's all.

Mind you i did try this with different pec pots on two seperate builds. So i don't think all those pec pots were defective.

[Medley]

Don't have to try it. It's pure nonsense. Kinda like "The leads are not straight but bent at two places to allow slight relief when components expand and contract due to heat." or your low gain/sustain PEC pots. Sorry buddy. I ain't buying any of it. I spoke up hoping to prevent anyone else reading this from believing it.

Thanks for this, Sluckey. A bit abrupt in the messaging, but it's the kind of information that should be recorded for the benefit of other new, future builders. This kind of nonesense gets repeated over and over and becomes gospel if not challenged.