adding reverb to spot meant for tremolo, badly bent leads :(

[mikepukmel]

Thanks Leo! Can't wait to get this finished and give it a listen!
Re mounting output away from PT, thanks, will do.
Do you solder the shield to the outside of these teeny plugs?

[Leo_Gnardo]

Do you solder the shield to the outside of these teeny plugs?

Yes, luckily the metal takes solder easily. If you want to be doubly assured, place a dot of solder on the plug first, you'll see it stick to the metal and spread a little. Then take your tinned shield braid & solder it on there, should take 2 seconds.

Some folks try to copy Fender's method, and spread the shield wires 360 degrees around the whole plug. Good for you, those who can manage to do that. It isn't necessary, and if the wire is plastic insulated between shield and signal wire, likely that insulation will melt before the task can be completed. Who wants to remove, re-strip, clean up the plug to try again. Not me! Been there, done that, got frustrated, now I don't do it anymore. Keep It Simple, Stupid! is what I tell myself. And anyone else who will listen.

[Tom Phillips]

...how to solder up low end RCA jacks: I got these cheesy RCA plugs: https://www.tubesandmore.com/product...or-type-3501mx
Did not look at them carefully before purchasing. There is no solder tab for the shield. I found a youtube video where the guy stripped a fairly long piece of the inner conductor, tinned it, pushed that all the way in until it stuck out the end of the jack tip, then just put a little solder on the end, and cut the piece of wire hanging out the end.

OK, but for these jacks, what do you do with the shield wire? Just by sheer dumb luck I had bought shielded wire that fits into the end of these jacks with a little bit of an interference fit unstripped. Should I leave the shield hang out over the insulation, twist and solder just a bit on the outside of the plug? The shield must be connected someplace?

Mike,
You have described the basics to solder shielded wire to the old style RCA phono jacks. However, the technique requires practice and good soldering skills as well as good wire with insulation that won’t melt during the soldering. Yes, the shield is soldered to the outside of the connector. I’ll add a photo of the finished vintage Fender assembly if I can locate one.

...A related question: if the shield is connected on both ends of both cables then won't there be room for a nice big ground loop?...

In general it’s a potential path for a ground loop. However, it doesn’t cause a ground loop in this case because the ground path is interrupted at the reverb tank connector. That is, if the correct reverb tank configuration is used.

Cheers,
Tom


Note that the old style RCA phono connector is not really necessary unless you want to duplicate the vintage style Fender reverb cable construction. In that case, for the correct look, you would want to use the vintage style coax wire with heavy the bare braded shield. For practical purposes on new builds or repairs it is easier to use pre-fabricated cables with right angle connectors. They are inexpensive and, of course, don’t change the sound.

[mikepukmel]

Thanks Leo: yeah, simplest thing I can do, that will work. I will twist and solder the shield on the outside, in one spot as you suggest. I barely remember what the vintage cables looked like, will google them, but yeah, no reason for me to try something that requires that much skill!

Thanks Tom: Re premade cables, I wasn't sure what to buy. As you wrote, something like 20 bucks for pre-made, wasn't sure if they'd fit, so I bought stuff to make the cables myself. We'll see how badly I melt things and maybe end up buying premade anyway. The replacement meter is on its way, so should be able to test the home made cables this week, as well as get a better idea what the bias is on this amp.

I didn't look carefully, but it sounds like the reverb tank doesn't connect the shield all the way through? Still too worried Im going to break something. The tank has 2 pieces of shipping foam, one over the springs and one under. The outer one slides out easily, but Im worried Im going to ruin something getting the one under the springs out. Its sitting under a storage bench where I can't damage it.

The tank has mounting holes, but I bought a bag as well (is the bag for vibration?). Do you guys slide the bag over the tank, and punch holes in the bag to put a loosely coupled mount on the tank so it wont flop around if someone tips the amp over (like slightly longer screws that don't hold the tank down tightly)?


Akkk, should a bought right angle connectors. <frown>

[Leo_Gnardo]

Im worried Im going to ruin something getting the one under the springs out.

Lift the springs carefully with a pen pencil chopstick whatever, and slide that foam out. Don't throw those foam blocks out, they may come in handy some other time for instance mounting pickups (says mister never throw anything away.)

The tank has mounting holes, but I bought a bag as well (is the bag for vibration?). Do you guys slide the bag over the tank, and punch holes in the bag to put a loosely coupled mount on the tank so it wont flop around if someone tips the amp over (like slightly longer screws that don't hold the tank down tightly)?

First cover the open side of the tank with a rectangle of corrugated cardboard, you can razor cut one from a discard shipping box. Then plug in your cables, slide the tank into its "sock", use a couple screws (washers help distribute pressure so you don't tear the sock material) at each end. You can tighten the screws fully. That's all that's needed in most applications, again straight out of the Fender standard operating procedures.

Don't sweat angle RCA connectors, they're really no better. I've seen many of them damaged, plus you can't easily bend the shell "fingers" to grab the panel connector tightly. Late 70's on plastic angle plugs started to show up factory installed on Fender and other amps. There's nothing superior about them except they save time in factory assembly. Just another so called "solution" that's worse than the problem it's trying to solve.

[mikepukmel]

Thanks Leo!

[mikepukmel]

Finally got the right board in. Due to my own mistake, I ordered another non reverb board. Got that in, figured out what I did, then ordered the right board. Got that in. Turrets are awesome! Everything sits up high, like a jeep with those big tires.

Pulled the components off the old board, carefully, straightened them out trying not to ruin them. Reformed the parts, soldered them in to the new board. Drilled mounts for the new board, dry fit (akkk one pin is off a little, will have to file one hole out a bit)

Removed the huge mess of solder, wires and lugs near the input jacks.

Cleaned up the new board a bit, re-measured all of the resistors to make sure I didn't screw up putting the parts back down. Almost close enough for folk music.

Ran out of time this weekend . Next weekend: double check the wire routing, mount the board, solder up the board to the pots, jacks, and socket pins.

The good thing is, the NEXT Deluxe Reverb AB763 I build will go MUCH smoother!






I ran out of blue wire for the bass pot wiring. I wonder how red will sound.

[Chuck H]

I ran out of blue wire for the bass pot wiring. I wonder how red will sound.

Red will sound hotter. Blue is a "cool" color. Red is a hot color. It will sound "hot". Not necessarily higher gain, but thermatically. It will SOUND like a higher temperature because the COLOR of the wire is similar to fire, which is hot.

[Leo_Gnardo]

Red will sound hotter. Blue is a "cool" color. Red is a hot color. It will sound "hot". Not necessarily higher gain, but thermatically. It will SOUND like a higher temperature because the COLOR of the wire is similar to fire, which is hot.

You bet, another well known hmmm, "fact." The hi fi nuts know enough now to avoid black wire, it's obviously bad for the sound. Red on the other hand, for the guitar crowd, can be a very positive thing. Red wire, yeh that's for high voltage, must do something good for the guitar signal too. And everybody knows red amps are louder. Red guitars too. And your guitar's louder when you use a red pick. It is possible to overdo it though. When everything you play comes out sounding like King Crimson then you know you've gone a step or two too far.

Gotta wonder whether this works for color blind guitarists?

[Enzo]

It is easy to joke, but this is important. As you know, red color is from longer wavelengths of light.. And light is part of the electromagnetic spectrum. But what makes the light longer wavelengths to appear red to our eyes is that the molecules of the red wire are longer. And longer molecules can align easier, resulting in smoother flow of electrical current. And that is why the red wires sound better, especially on bass notes.

Ever notice how on many two way speaker systems, the woofer is wired with a red and black, but the higher frequency tweeter had a blue wire? This is because the tweeter need higher frequency sound, and thus shorter wavelengths. Blue has shorter wavelength than red.

For some reason Peavey chose to wire their woofers with blue wires and the tweeters with red. This results in a sound with less emphasized bottom end and a less pronounced high frequency spike. Fender on the other hand used black and white wires for speakers. The result is a less colored sound than speakers with red and blue wires. Compare a Fender Twin Reverb with a Peavey 5150. See how much less distorted the black and white wires make the Twin compared to the 5150?

It's all right there in your physics book.

[mikepukmel]

It is easy to joke, but this is important. As you know, red color is from longer wavelengths of light.. And light is part of the electromagnetic spectrum. But what makes the light longer wavelengths to appear red to our eyes is that the molecules of the red wire are longer. And longer molecules can align easier, resulting in smoother flow of electrical current. And that is why the red wires sound better, especially on bass notes.

Ever notice how on many two way speaker systems, the woofer is wired with a red and black, but the higher frequency tweeter had a blue wire? This is because the tweeter need higher frequency sound, and thus shorter wavelengths. Blue has shorter wavelength than red.

For some reason Peavey chose to wire their woofers with blue wires and the tweeters with red. This results in a sound with less emphasized bottom end and a less pronounced high frequency spike. Fender on the other hand used black and white wires for speakers. The result is a less colored sound than speakers with red and blue wires. Compare a Fender Twin Reverb with a Peavey 5150. See how much less distorted the black and white wires make the Twin compared to the 5150?

It's all right there in your physics book.

That's it, Im gonna start all over, tear out all that wire and put in all red!

[mikepukmel]

You bet, another well known hmmm, "fact." The hi fi nuts know enough now to avoid black wire, it's obviously bad for the sound. Red on the other hand, for the guitar crowd, can be a very positive thing. Red wire, yeh that's for high voltage, must do something good for the guitar signal too. And everybody knows red amps are louder. Red guitars too. And your guitar's louder when you use a red pick. It is possible to overdo it though. When everything you play comes out sounding like King Crimson then you know you've gone a step or two too far.

Gotta wonder whether this works for color blind guitarists?

Cool, I could sound just like King Crimson just with wiring changes?

[bob p]

back to Mike's question about bends in the component leads:

I see an awful lot of turret board and eyelet board amps being built today by DIY types who appear to stress the layout's visual appeal as a most important trait. In those builds you tend to see components that have ultra-straight leads that are wired taut from one anchor point to the next, as that creates a layout that is visually appealing. what's interesting bout this is that it's absolutely the wrong way to wire up a turret board. it seems that some of the nuance associated with the old military spec wiring techniques is becoming lost as inexperienced DIY builders mimic other inexperienced DIY builders. in some cases it gets so bad that it looks like the blind are leading the blind.

proper old-school milspec wiring techniques require a gentle S-curve to be placed into the component leads, so that expansion and contraction of the leads during thermal stress does not create tension where the leads insert into the passive component. the idea being that the curved shape of the lead allows room for expansion/contraction without tugging on the component itself. in some respects that sort of wiring technique is similar to using an expansion joint in concrete to avoid cracks.

I've seen some other pretty lame attempts at turret board wiring, like this thread at TGP that popped-up when I was looking for photos to illustrate the "S" shaping that I mentioned in the preceding paragraph:

http://www.thegearpage.net/board/ind...hnique.693587/

In that thread, the OP asked which soldering method was proper, A or B:



My response would be that both are dead wrong. both A and B amount to bad technique, where someone is treating a turret as if it were a tall eyelet.

The proper way of wiring up a turret is to wrap the lead spirally around the turret to provide stability at the point of attachment. Optimally, the wire lead should be left long enough when it is clipped so that it sticks out of the solder joint, to allow the next guy to use a pair of needle nose pliers to grab the lead for removal when de-soldering. But nobody does this any more. Everybody tries to make things look "neat" and as a result their "neat" projects become unnecessarily difficult to service later on.

Interestingly, there are stories that quite a few Fender amps that went out the door without having solder on some of their terminals, and the amps worked properly for decades in spite of having no solder on the connections. That just goes to show that a well-made attachment is based upon a solid physical connection, not using solder as glue.

[Chuck H]

Absolutely right! The ideal is that there is metal to metal contact and the solder is conductive only for the purpose of not getting in the way. It's intended job being to hold already connected things in place. And yet I trust the conductivity of solder all the damn time. I make eyelet boards. On an initial build I under bend component leads so there is always lead to eyelet contact. Then after soldering I snip off the excess. BUT... Once the build is complete and the board is mounted, if I need to make changes or effect service I don't suck the eyelet clear and lift the board to make the same under bend in the new component. I do like the rest of us, including you. I pre bend and snip the component leads to reach eyelet to eyelet, heat the solder and just stick them in. I usually put a dot of fresh melt flux core on the joint to flow it. According to your rundown above this is entirely wrong. Don't lie though. I know you do it too

[Leo_Gnardo]

Interestingly, there are stories that quite a few Fender amps that went out the door without having solder on some of their terminals, and the amps worked properly for decades in spite of having no solder on the connections. That just goes to show that a well-made attachment is based upon a solid physical connection, not using solder as glue.

Not just stories, I've had actual encounters with a few of these. And not only Fender but surprise - McIntosh! In Fender's case, on very rare occasions, say 2 or 3 over the course of decades, a board or tube socket eyelet someone just forgot to solder. Wire ends crammed into the eyelet, no bend, no attempt at a good mechanical connection, as they do. OTOH, McIntosh did have mil spec wire bent into hook and crimped, or wrapped around a terminal post, then oops no solder. Makes me wonder how may owners passed these amps along, maybe having experienced intermittent noises or signal dropouts, until someone - me - had a look inside and fixed the problem.