Tube Talk - part 5 - Two Prong or Not Two Prong. Replacing the cable on your vintage tube amp

A discussion the pros and cons of replacing the power cable on your vintage amp.

[derpdorf]

So I've just accidentally deletedbmy comment like three times right now! So im gonna make this short and sweet lol.. I finally was blessed with the opportunity to purchase a vintage maestro Echoplex (EP-3)..I've been enjoying it to the fullest extent and the unit is in tip top shape with new tape etc. Although I did notice that it still is rocking the old 2 prong power cord, and I assumed it was the idea to keep it original as possible. I noticed when I looked closer that there is a skinny green wire in there that's actually not connected or soldered at all. It just ends right where the 2prong end is obviously clipped. About was dwelling on this since I noticed it. Cuz the other thing is that it's just a wee bit noisy with a slight hum when you get the volume up to about 5 or more.. Most people online mention how these old units are always gonna have a slight noise to them..but now im thinking I should Adrea's the issue with that ground wire.. Yeah? It's not shocking me in any way or acting up, just a slight 60 cycle sounding hum..I'm wondering if I went ahead and grounded that clipped green wire to the chassis properly, or just replace the entire vintage cord with a fresh 3 prong one, would it make the hum a little less apparent, or at least help the unit function a little more safely / stability wise. Most obliged for the knowledge dropped in your video, what do you think? Just leave it as is, or replace the old cord with a proper 3 prong and ground it to the chassis or what not..? 😓

[jimmystreeter]

How do you find which side of the 2 prong should be polarized? For the “ground lift”? Method

[augustwestusa]

And I also wonder about replacing the cord that goes from the top of the amp to the speakers below. I was going to take the cord into a music shop and see if they have one I can replace it with. The one I have, has a little electrical tape around it, and I was messing around with it and it kind of came apart, not sure if I put it back together correctly...hope those cords are not difficult to replace (the three little prong type within a circle)!

[wolftickets]

My vintage turntable and stereo receiver (late '70s/early '80s) both have two prong non-polarized plugs.

[backlineguy]

Hey Gary, just picked up a 1970 Kustom 100 head, and it has the 2-prong power cable...I want to change it to a 3-prong grounded plug/cable...can you make a video on how to do this to an old vintage Kustom 100, or point me in the right direction? Thanks!

[FIBONICITY]

I just got a vintage Peavy it appears the previous owner rewired with a 3 pong wire but took out the ground. Is it safe to plug into a 3 prong socket? Im guessing at min there will be a hum.

[jimmystreeter]

Where can I get one of those adapter plugs that you show at the end of your video

[augustwestusa]

I'm having this problem with an old Vox amp. We were getting shocks from a microphone, when playing a guitar...so I figured I need to change out the cord. But I was hoping this video would tell me how to do that! Or are you saying all we have to do is turn the plug around? Can we just cut those old cords and replace the head with a three prong? Or do we have to replace the whole cord at the source? That looks like it would be very tricky. I don't think my amp has tubes. It's a solid state. Anyway. Hopefully I can figure it out. Thanks for your video.

[michaelmoore]

@0:46 Hmmm. Bipolar, explains why my tube amp is sometimes moody and aggressive....is there a Lithium battery mod for a 67 Bassman with the AB165 circuit? Or perhaps a set of Lithium 6L6's and/or a 12AT7 and/or a set of 12AX7A's? Or do I just need to make an appointment ? ;)
Thank you, very informative.

[nick]

What about the so called "death capacitor" that was supposed to prevent 110v from being on the chassis? Is it necessary to clip out of the circuit if upgrading to the 3 prong cord?

[marcotaticchi]

Thank you for the video but how can you check which one is the Hot?

[jeremypoythress]

Proper wiring in the outlets is more important than the rig because if something electrical fails it should kill the power safely when it trips the breaker so you don't start burning down the house. Operation is one thing to consider before upgrading an amplifier to 3 prong plug but if you don't have 3 prong outlets keep in mind your life is potentially on the line in the balance between you and the mains power supply is a inevitable death cap like a ticking timebomb.dont use those cheater plugs unless you know for a fact you need one for your audio equipment to function.

[mikeyjohnson]

Is it okay to plug a newer 3 prong amp into one of those adapters that turn a 2 prong into a 3 prong? I have an old house I only have 2 prong outlets. Thank you!