Scott LK-72 rebuild

I'd stick with the same values for the can capacitors. Voltage can go up, but match the capacitance. I'll post up the pictures of my HayseedHamfest caps when they get here. I bought the set, but I think they are available individually.

Just finished scoping all my orange drops for which end is the outside foil. I can tell you, even on a digital scope, holding the cap against the power chord. It's hard to tell. Hopefully that will = low hum.
 
Let me know how that goes...I got orange drops as well. Aren't these non polar?? If they are non polar does the direction make a difference?

I ordered #18 ga wire X 8 colors for $22 per 500' roll, #20 for $19 & 22ga for $16 which was considerably less than AES, guess it payed off to be an electrician!! I'll be doing some rewiring when I get my caps
I'd stick with the same values for the can capacitors. Voltage can go up, but match the capacitance. I'll post up the pictures of my HayseedHamfest caps when they get here. I bought the set, but I think they are available individually.

Just finished scoping all my orange drops for which end is the outside foil. I can tell you, even on a digital scope, holding the cap against the power chord. It's hard to tell. Hopefully that will = low hum.
now
 
Polarity should not matter on orange drops. But their is still an inside and outside foil. If you scope them you see a slight difference in interference. It may not even make a difference. But I have access to a good scope, so I figured why not.
 
My cans arrived today. Very impressive build, even if they don't copy the originals in design. My originals are fine. So I'll shelf them for preservation.

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Got my 16ohm load resistors today. Now once my other parts get installed I can at least properly balance my tubes. Hope your caps show up soon.
 
Got my 16ohm load resistors today. Now once my other parts get installed I can at least properly balance my tubes. Hope your caps show up soon.
Caps showed up today....just got the kids to bed, debating weather I wanna start now and be up all night or be a lazy ass and wait til morning!
 
Spent a good chunk of the day working on wiring and replacing all the capacitors on the bottom. I only have the 6 left on the control pots and he cans.

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Nice work. I replaced the Ceracaps in mine with orange and the results were noticeable.

Every one of the old caps I pulled tested spot on though with my Fluke. While it was dead quiet before the rebuild after definitely gave it a crystal clear top end.
 
Those capacitors on the tone controls are a challenge and can take some time to do properly for sure. The selector switch is even more fun. Pictures below are of my first edition 299 just as an example to support your effort! "It's a jungle out there!"

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Yes, and take care around the pots and switches: I managed to break a lug on the loudness switch on mine doing the resto.
 
Another 5 or so hours of soldering and the Hayseed Hamfest Cans are installed. I had to rotate one of the cans 90deg to face all the labels to the back. But I think it looks pretty fancy.

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Nice work, I recieved my can caps today! I got a good jump on replacing other caps and just have the 6 on the tone controls left to go. I'm think I'm going to give her a full rewire as well, to me the wiring looks like the south end of a dog going north!

I'll post pics later tonight when I get a lil more done!
 
I just got all the caps underneath replaced and decided to give her a listen to see how it was.....holy cow! It's been on for about 15 min or so and it seems to be so much clearer than before and this is without replacing the can caps....this will give my 340b a run for its money!! Seems like it's so much more detailed and so clear!!!!
 
Wait 'til you get the multi-cans replaced. I found my rebuilt LK-72 to have as much tube goodness as my MC-60's. It's the tube rectifier, IMO.
 
I went overkill and grabbed some 16ohm 120w wire wound non inductive resistors. They were $8 each. So no big deal really. Are you running yours right off 120vac?

I took tonight to restore a Calrad Variac. See if I can find a sweet spot for the best sound. It should look good stationed near the amp too.

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I brought it up on a variac just incase I moved anything or made any mistakes....once I seen everything was good I set the variac on 117v and let her rip! Im gonna follow scott on this one, they call for 117v so I'll trust them. I'm still amazed on how fantastic this sounded!!!!
 
IMG_0718.JPG Can caps installed!! That and a brand new quad of rca 7591 tubes and a new quad of 12ax7 sylvania tubes Mullard 5AR4 and 2 6GH8 GE tubes and man this thing is rockin!!!!!!

When I got the caps done a had a hum in one channel in the phono stage, replaced the preamp tubes and this bad boy is dead quiet with no hum or static, I can't believe how great this sounds, better than any tube amp I've heard! Or mabye I'm just hearing stuff because I did the rebuild....
 
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