Tweed Princeton 5F2A - Learn diagnostic and repair techniques to make this amp safe and original.

In this video, you may learn skills that apply to your amplifier, such as the correct way to wire a fuse and power switch for safety, and how to make the amp slowly and safely drain the filter capacitors. You will learn how to test for leaking coupling capacitors, how to calculate the static dissipation of a cathode-biased amp and how to convert pico and nanofarads to microfarads.
Ted Weber was the Leo Fender of amp speakers. Chris relates a couple of Ted anecdotes (apologies to Chris’ customers whom he has tied to a chair while force-feeding such anecdotes).
Thanks go to Sunburst Music of Coogee, Australia, (the current owners of this gorgeous amp) for allowing Chris to secretly covet this piece of musical history.
Index
00:00 Introduction
01:15 Visual Inspection
01:50 The White Elephant
03:23 Wrong Reservoir Filter capacitor
04:44 Filtering is important with “cheap” filament/heater wiring
06:15 Let’s make it safe!
07:20 Are Americans odd?
09:27 The correct way to wire mains to switch and fuse
11:20 The Death Cap: To leave or not to leave?
13:00 Tweed Princeton…A cousin to the Champ or the Deluxe?
15:35 Checking the ESR of the Electrolytic capacitors
18:10 Why are leaky coupling capacitors a problem?
19:15 How to convert picofarads (pF) to microfarads (uF)
20:20 Differences between the 5F2 and 5F2A Princeton
24:35 How to identify a leaking coupling capacitor
26:09 Let's make this classic amp a little bit safer by draining filter caps
28:55 How to measure and calculate the static dissipation at idle for the 6V6
33:22 First soundcheck of this 1959 Princeton for undesirable noises
35:00 Install a Weber 8A125 AlNiCo and memories of Ted Weber
40:25 The final Sound test. Thanks to Sunburst Music of Coogee for the privilege.
42:34 Ending. Please LIKE and SUBSCRIBE.

[@davebolden4355]

Would your esr values be accurate with a resistor in parallel in circuit while you take test readings??

[@theguitaramptech]

That’s a very good question, David. If there is a capacitor in series, it’s very easy to see because the C reading will be higher than the stated value. However, if there is a resistor in parallel, the ESR value would be slightly smaller (depending on the parallel resistor value). This would mean that I could be more likely to accept a capacitor than pull it out. We have to remember that my goal is not to have an exact value of Dissipation or ESR, but rather a Good/Bad indication. If my chart shows a maximum of 2 ohms and my ESR meter reads 2.2ohm, I would most likely leave the Cap in service. If it reads as 10ohm, I would definitely replace it. I also use my subjective judgement. If there’s a buldge, or it’s a known troublesome brand, I will show it less mercy. With vintage gear, I am always conservative. I have a passionate dislike for shotgun replacements of components .

[@jpalberthoward9]

I disconnected the negative feedback loop on mine, and I also added a 25/25 bypass cap on the second stage of the 12AX7. These two changes livened it up quite a bit. I'm not concerned in the least with absolute originality. This one's a keeper. No flips in my world. Ever. The next time this one changes hands will be at my estate sale.

[@theguitaramptech]

That's great. Both of those changes are easily reversible. That's quite a bit more gain there. I'm glad you're enjoying your amp even more.

[@jpalberthoward9]

@@theguitaramptech I was changing the cathode resistor anyway because it was out of spec. I said "I wonder what would happen if I bypassed this stage with a cap?" It was a good move, as was removing the feedback loop. It didn't turn into a death metal monster or anything like that, it's still a Tweed Princeton, there's just a little more of it. Maybe just a bit more high end and a little less mud in the low mids.

[@theguitaramptech]

@@jpalberthoward9 Good work. If you want to reduce some of that low-end flatulence, try reducing the first-stage cathode bypass cap from 25uF to something around 2.2uF.

[@montygore1200]

I have come to the conclusion after watching you and Brad you aussies are crazy as us texans.Lots of fun.

[@theguitaramptech]

You are definitely right, Monty. Back in my hey-day, I did shows in Dallas and Houston, and yes, they were GREAT fun!

[@jedishaw6771]

Great video! Thanks! Love working on these old amplifiers, always wondered what sarder was as it's actually solder! 😁

[@theguitaramptech]

HAHAHAHA! That's right Jedi!

[@kbkman7742]

Awesome. Just wanted to add 2c for anyone restoring an old fender, as well as checking leakage on the caps I have found it is really useful to sniff around on the fibre board itself. I have cured a few elusive noise issues by getting rid if dc leaking in the board. Same with the cloth wire. Chris, you are a very patient man replying to some of the comments here, everyone is an expert I guess.

[@theguitaramptech]

Thanks KB. If someone makes the effort to write a comment I will make the time to reply. Its like someone ignoring you when you talk to them. Some EXCELLENT suggestions KB. When I just can't find a logical reason for stray voltages, conductive fibreboards may hold the reason. I can't say I've found conductive cloth wire insulation, but it sounds feasible to me. Thanks for that suggestion.

[@edwardhannigan6324]

Hey Chris..That's a little gem..Nice to see the original Fenders..Love the walk thru and tech info. Lots more learned, thanks for sharing. Great playing demo at the end..Take care..Ed..uk.😀

[@theguitaramptech]

Hey Ed. I reckon we'd both have drinking problems when I get over there!

[@lestelie4410]

Thank you for another fun and educational video, Chris. I always learn at least one new fact or technique from your videos. I really liked the way you test for leaky coupling capacitors. I never trusted a multimeter to tell me the real story.

[@theguitaramptech]

Thank you for your kind words, Les. You are right. Because of the very high input impedance of a DVM (which is what you normally want), you can't trust it to give you an accurate understanding of coupling capacitor leakage.

[@GRBAquatics]

Nice Work. Very Interesting, Entertaining and Informative as always. Cheers

[@theguitaramptech]

Thank you so much GRB!

[@soapboxearth2]

I would love to get my hands on a vintage princeton!! I just built another 5f2a based circuit. I used a blackheart little giant 5 watt amp as a donor. I added a matshall value tone stack, raw switch , bright switch and the variable nfb pot. I was hoping for a JTM-5 sort of thing.. and i pretty much acheived it. Im starting to love that circuit. Suprisingly loud for 5 watts!! I was suprised to see 5 volt taps on the pt. The original blackhewrt used a bridge rectifier .. i used the 5v taps on a 5y3.

[@theguitaramptech]

Very cool. Yes, 5w is surprisingly loud.

[@amoruzz]

Good video, thanks 👍 Weber speakers A+ 👍

[@theguitaramptech]

Thank you, amoruzz!

[@vintagetubeamplifiers]

What a beauty!

[@theguitaramptech]

Mate, you should have been in the workshop! I think I might have been clipping the mic or preamp in the soundcheck.

[@soapboxearth2]

I just finished my 5th amp build. A 5f2a. I used transformers from a crate v5 so no rectifier tube . I added a nfb pot (5k to 100k), which works wonderfully, credit to uncle Doug for that idea! I added a master vol as well. I plan to get some hammond transformers with the proper 5 volt taps eventually and build another. I will be incorporating a Garnet Herzog (a'la Randy Bachman and Gordy Johnson) into the amp next time.

[@theguitaramptech]

Great work, Soapbox. I'm glad to see you reused transformers. I assume you checked the impedances were OK for the OT? The output tube type and the speaker load need to match. I am sure @uncledoug did a video on that very topic. Cool having variable NFB. I have never come across a Garnet in Sydney, but if Randy used one, I bet it sounds great.

[@soapboxearth2]

@theguitaramptech thanks! The original amp ran a el84 and I'm running a 6v6 so I think I'm good. The ot only had 8 ohm taps. I'm using a 20 watt greenback reissue with it. Sounds real good.

[@Splattle101]

Good speaker choice. When I built my tweed champ clone, I used a Princeton sized cabinet with a baffle cut for a 10" speaker. The speaker I chose was a Weber 10A100. It's got a smooth cone (with all the problems that entails) and pushes about 15 Watts downhill, with the wind behind it. It's such a good speaker. Fan-phreakin'-tastic.

[@theguitaramptech]

You are spot on, Bladder! After hearing this amp, I have decided to build myself a Tweed Princeton and I have also decided on a 10" Weber!. Great minds...

[@stevesheekey5263]

@@theguitaramptech A video on the Tweed Princeton build would be fantastic, I would like to build one of those too... and a VOX / Marshall hybrid....

[@theguitaramptech]

@@stevesheekey5263 That's a great suggestion, Steve. Otherwise, I keep putting my projects at the bottom of the priorities list. Oooh, I like the idea of a Vox/Marshall combo. If you haven't already, take a look at the Marshall 1974 18w Hand-wired, and you may find yourself halfway there. I own one and (after my improvements) it sounds fantastic...but that another video :)

[@dwightbehm2886]

Again love you man.

[@theguitaramptech]

Back at you, Dwight. See, I even love your name. There is no Dwight in Australia. Or Duane. Short true anecdote. A young man in an electronics store had a name badge with "Duane". I said, "Your dad must have been an Allman Brothers fan". He looked at me blankly. "Does your dad play guitar?" He did. I went on to explain the significance of his name. Then Duane said to me, "That may explain why my brother's name is Hendrix"!

[@dwightbehm2886]

@@theguitaramptech Hi Chris. Let me explain about my name. My Dad picked it out of a book for names I did not like it untill I got older. Dwight David Eisenhower is one of my country's president from back in the 1950s 5 star general back in WW2 I don't deserve the name. My grandpa liked Eisenhower. I am a ham radio operator I have held a license for amateur radio now going on 32 years. I like talking with people in Australia Canada and Great Britain on the ham radio it gives me a little Joy.your new friend Dwight. God Bless you.

[@theguitaramptech]

I think Dwight is a very good name, and I suspect you have grown into that name...and deserve it. Great to hear from you my sodder-loving, side-walking, friend. Stay well. We have just celebrated Orthodox Easter (May 5). If you have any Greek mates, call them up and say "Hristos Anesti" (Christ has risen).

[@simonkormendy849]

If this had've been my Tweed Princeton 5F2A amp, first thing I would have done is go straight to the Evatco website and order a new 240V AC 5F2A power transformer online and used it to completely replace the original stock power transformer, and then I'd go through and re-do all the mains wiring to make it compliant with the current Australian 240 V AC mains wiring code as a matter of course, before even thinking about plugging it in after replacing any faulty components, especially if I knew the amp wasn't going to be used anywhere outside of Australia.

[@theguitaramptech]

Sorry Simon. I didn't realise you were an Aussie for my previous reply (gasoline comment). I agree with everything except the change of power transformer, no matter how tempting. A power transformer WILL change the sound. Maybe not as immediately as the OPT, but it will have different windings, core, laminations, saturation, etc. But, Simon, to show what a hypocrite I am, I did change the PT on my 1963 Fender Concert because I got sick of carrying a step-down to gigs. But now that I now longer get loud 45w gigs, I am seriously thinking about returning the original Schumacher transformer to duty.

[@adamcherry434]

Hi Chris, watched the vid from start to finish, the humor is v important for those that don't follow electronics. Can I just say a big word for Webber speakers and the Ted Webber Speaker Company. You shipped me a 10 inch Webber for my Vox AC 10 and it sounded great but inexplicably some thing happened and it stopped which is a very very rare thing for a Webber speaker to do. The most amazing thing that happened after that though is Webber agreed to send me a replacement speaker from the US (*@#!!$$$) without even having me send it back to them in the US or to an Australian agent to be officially checked. Webber have v grueling pre sale testing perimeters for each speaker and you yourself tested the amp through its paces before shipping to me. Whatever caused it to stop is more likely to to do with me somehow more than the Webber failing. So I am just as impressed with Webber family Customer service as I am with the quality build and sound of their speakers. Cant praise the Ted Webber speaker company enough in all aspects of business. Thank you, Adam Cherry WA

[@theguitaramptech]

Thanks for your feedback Adam. I have lost track of how many Weber speakers I have installed over the past 30 years. I have never had a failure. When I spoke to CJ at Weber about your situation, he was equally surprised. I am happy, but not surprised, that Weber stood behind their reputation to ship a replacement speaker at their expense to you. That's a mark of excellence. I am very happy that you're enjoying the sound of your upgraded AC10. I think they're a great little amp.

[@tim9778]

Hi Chris. Not sure if others have mentioned this but I think you made an error in the 6V6 dissipation calculation. You measured the voltage across the cathode resistor and used ohms law. Nothing wrong there, if you want to know the TOTAL current through the valve/tube-anode/plate & screen current. Then you used this current, along with your Anode/plate to cathode voltage to work out the anode/plate dissipation and got a high result. Of course you did, because you didn’t use the current through the anode/plate and anode-cathode voltage. As far as I can see you didn’t factor in the screen current( probably some 5-7mA). Since the cathode current you used also included a slight margin( the additional screen current) anode/plate dissipation is probably a little under 12 watts, right where it should be.

[@theguitaramptech]

Hi Tim, thank you for your comments. You are quite correct. I normally allow around 8% for screen current. I always have an internal struggle about how much detail to go into in the videos. Most are an hour long as it is. When I use my EuroTubes Bias probe, it reads the Plate current not the combined plate and screen, but not many people have access to one of these instruments. I was trying to demonstrate how MOST people could set the bias better than what their amp left the factory, which is almost always too hot. True, my "Bias-Lite" method may lead to a SLIGHTLY cooler setting, but I definitely prefer that to a too hot setting. I always check a cathode or fixed bias setting with my oscilloscope as the quoted maximum percentage figure is only a design figure. The oscilloscope shows you what is really happening in this particular amp. You made a valid point, but its too complicated for where I want to pitch my videos. An advanced Tech, like yourself, would know this and account for it, but only if they measure the real screen current and not just estimate a percentage (like me), or a screen current (as you suggested). Thanks Tim!

[@jjs3863]

Thank you for the enjoyable video m8

[@theguitaramptech]

I am very happy that you got something out of it. Have you subscribed yet? I have some exciting things coming up. Are you in Australia?

[@jjs3863]

@@theguitaramptech yes I’ve subscribed but no, I am in US. I have started down the wonderful road of tube amp repair. Well just a couple steps at least.

[@theguitaramptech]

@@jjs3863 Aha! The "mate" threw me. Well, my exciting news may not apply to the USA ...yet.

[@jjs3863]

@@theguitaramptech either way, cannot wait to hear the news. I have a group of blighty friends, and when we chat there’s a lot of that ‘mate’ stuff flying around. Guess some of it stuck to me. Anyway. Great channel! Love the content. Do you have a patreon or something similar?

[@theguitaramptech]

@@jjs3863 HAHA! Love the term "Blighty". I haven't heard that since Captain Cook was a lad. I haven't gone the Patreon way yet. Although this KZbin channel earns me a whopping 2.8 cents per hour (OK I'm exaggerating....of course it's much lower), I do it out of pleasure in talking to folk like you. The only downside of amp repairs is that its a very lonely job. I'm sure my customers keep looking to the door to escape from the old guy who won't shut the hell up! I might look into Patreon once I catch up with my repairs!! (Lawdy, but I make myself laugh That day will never come.) Stay well, JJ.

[@markusf.3441]

Hi Chris, very interesting video about a wonderful amp. Maybe Americans are odd, but then we Germans are even more odd.😬 We can turn our power plugs 180 degrees. So in Germany you can never know which side the phase is on. Cheers

[@theguitaramptech]

Oh no Markus. Run. Leave Germany before you get electrocuted !!

[@johnpierson8398]

Really good vintage Princeton video! I found it particularly informative how you were very hesitant to change out any series coupling capacitors. The uF values can vary some without major impact on the tone of the amp Also, I now see why ESR on coupling capacitors is not so important, but leakage currents are very important to be low. I know that uF and ESR values on the bulk capacitors are important, but leakage current is not very significant. I always learn something from you!. Most importantly - the sound! The sound with that Les Paul Deluxe with the mini humbucker pickups was glorious!

[@theguitaramptech]

Wow! Thank you so much, John. Your comments make the time investment in producing the videos (especially editing) all worthwhile. I am so glad you get something out of the videos. I love that Les Paul Deluxe!! Its a 1979 that weighs in at a hefty 10.2lbs, but the sound!!

[@jonlanning8973]

Hey Chris, great video. Question, without having an ESR meter, what would be the best way to test cathode bypass caps? Would measuring capacitance on the multimeter be a good indicator?

[@theguitaramptech]

Hi Jon. The condition of a cathode bypass cap is not critical to the amp's health, unless it fails Short. The ESR is the measure of the internal resistance and can be an indicator of an upcoming event....failure (due to internal heat build up). Simply measuring the capacitance is a DC way of measuring a reactive (ie AC) element. It is good enough for a bypass cap for home use. The problem is that many Tech take the easy option, too. Its usually because they're, cheap, or lazy, or simply don't know what ESR indicates.

[@jonlanning8973]

@@theguitaramptech thanks Chris, good knowledge right there. I had a search through Jack Darr as well and it says that you can measure the Dc resistance of a cap.. if you get any reading at all, the cap is bad. A more crude ESR measurement I suppose. Between that and measuring capacitance (as you mentioned) you can get a pretty good handle on whether a cap is good or not with just a multimeter. Thanks again, keep up the good work

[@theguitaramptech]

@@jonlanning8973 yes, as you say, using DC resistance to measure ESR is very crude. The reactive impedance of the capacitor depends on frequency, and the ESR will change with frequency. It is best to measure a capacitor for capacitance and ESR at the operating frequency of the component. Long story short: using the DC resistance is better than nothing :)

[@stevesheekey5263]

Hi Chris, Great video and fantastic to see these classic amps serviced to live another 50 years! My I ask your advice, if the B+ is too high on an older amp say a 5E3 or similar fender design (ie 398) because of new PT or higher modern wall voltages, is it ok to install 5W zeners to the PT Centre Tap to ground to bring down B+ to around 360. Or is there a better way to do it? Any harm to PT using the zeners to drop the AC into the rectifier tube. Thanks for your videos, learning a great deal from watching them. Regards Steve

[@theguitaramptech]

Agreed Steve. It is such a privilege to work on these classic, and then hear the results. I have had to return a couple of "uneconomic to service" solid-state amps from the 70's and 80's due to a lack of parts. But, as you said, these old tube amps can live forever, Putin permitting.

[@theguitaramptech]

Sorry Steve. I missed the second part of your message. You can use a Zener, or a couple in series with the centre tap to drop your B+, or a resistor, but they will get hot. You may need to heatsink it to the chassis, in which case you had better make damn sure you have a good reliable soldered connection to ground. Also keep an eye on your heater voltage if you have a elevated mains supply. Have you tried a different rectifier tube? If a 5Y3 is still too high, try a 5R4 (not 5AR4).

[@stevesheekey5263]

Thanks Chris, amp came with 5AR4, way too high B+, put in 5Y3 which dropped it down slightly, will try 5R4. Thanks Chris

[@stevesheekey5263]

@@theguitaramptech x1 15v 1N5352B and x2 12v 1N5349B and the 5Y3 have dropped the B+ 1 to 361V. Time to search for a speaker for the 5E3 - 12A125A ? Thanks Chris

[@theguitaramptech]

Good work on the B+ drop. Hopefully sharing that voltage across the 3 diodes overcame any heat issues. If you ever have time, pls send me a photo (email?) of your diode installation. I owned a (beautiful white basket) Weber 12A125, with ribbed cone. I a moment of madness I sold it to a customer looking to upgrade his Deluxe. His amp sounded great, but I lost one of my favourite speakers.

[@williamgombert7710]

Very good and intresting video. Thank you! Couldn't it be that the voltage on the filtercap wasn't dropping down due to the absence of the 6V6? Do you suggest that extra 220K or 330K resistor on all the tweed Champs and Princetons? Would you mind to share the max ESR reading chart you used? Greetings from Flanders

[@theguitaramptech]

Hi William. Wow! Flanders has an amazing history. Its on my bucket list. I agree, that having the 6V6 in place may give a path to ground for the B+, but only until the Cathode cooled. There should be no physical connection between the plate and any other element inside the tube. The heater voltage would stop as soon as the power is removed, especially if there were no Standby. The drain resistor is really only there to protect you and me. Most normal people would not be accessing the B+ with clumsy fingers. Of course, I would share the ESR chart if I could figure out how to do it. I am happy to do a video on ESR and why it is important and how to measure it.

[@riley0187]

Thats what I thought, can't believe 300+V holding charge like that...Wow

[@theguitaramptech]

@@riley0187 that’s so right, mate. It would kick my aging arse across the room and all the way to heaven.

[@williamgombert7710]

Hello Chris, Thanks for your quick reply. For the ESR chart. A video on ESR would be great. Or if you could give a short close-up in one of your next videos, I could take a print screen. Or i can leave my emailadress on your website. Whatever is the easyest for you. Thank you in Advance

[@theguitaramptech]

@@williamgombert7710 good suggestion. I will do an ESR video but that may be a while off. Send me an email through my website contact page and I’ll send you a photo. I’d give you my email address here, but I know I will be swamped with 157 junk emails by the morning.

[@grahambambrook313]

You have a LP Deluxe Gold Top!!!!!🤪 Wish I still had mine. I bought it new in 1974 for the princely sum of £360 but had to sell it coz I could not keep up the HP repayments when I left my job. 😞

[@theguitaramptech]

I have always wanted a minihumbucker goldtop, Graham. I passed on one about 30 years ago, because it had started to go green around the "forearm rub" area. Idiot that I was. When this came up at Sunburst Music (Sydney) I was not letting go. I hope you can find a replacement to heal that gaping wound :)

[@grahambambrook313]

@@theguitaramptech 'Bin gaping a long time now. Funnily, it was only about ten years ago that I realised it had mini humbuckers. Didn't know there was such a thing until then. Anyway, I have to make do with a couple of far eastern axes these days; a rattly (must give it TLC) Aria Pro T-60 and a PRS Santana. Both OK but......... I made up for it with an "impulse" purchase of an Ovation Adamas II 12 string during a long weekend in Prague. I only bought it for two songs (can you guess?) so a bit of an extravegance at 54,000 CZK!! 😁

[@theguitaramptech]

I also have a PRS Santana SE. I replced the stock pickups with Duncan Antiquities. Its a beautiful guitar. You can see it in the Mesa Mark 1 - Part Two video. Hmm...12 string acoustic?? Hotel California, Eight Miles High (The Byrds), Wish You Were Here (Pink Floyd), ? Any good?

[@grahambambrook313]

@@theguitaramptech I'm impressed!! Spot on (other than .The Byrds). Was it really that obvious? Must be an age thing. Beautiful guitar but the back bowl is the same shape as my belly these days which makes it awkward to play. 🤣 Also, the battery is a bitch to get in and out and drains in no time if I leave it in so I need to figure out the switching when I get time. I'll look up your Mesa video. Only discovered your channel last week but found it highly entertaining (and informative) so far. Thanks from Pommy land!

[@theguitaramptech]

@@grahambambrook313it was a good guess. I mean how many Classi 12-string songs can there be for a baby-boomer like me? The switching is usually done by the output jack which has a contact that opens when the plug is removed. Check that out first before you come up with your own switching system. Its so good to have another Pom on board.

[@jimcatanzaro7808]

I’m building one now from scratch using old ww2 tubes and metal almost there just have to wire it up

[@theguitaramptech]

Very cool, Jim. I bet its going to sound great, just watch your lead dress and how you run the heater wires.

[@TheVoluntariast]

Why would you use a Weber speaker instead of a Jensen P8R? I have done a lot of testing and I have never found a Weber that sounds better than the Jensen RI. I am curious.

[@theguitaramptech]

Hi Voluntariast. Thank you for taking the time to share your thoughts on speakers. Fortunately, tone is SO subjective that we can have no argument. To my ear, Weber speakers are the finest handmade speakers available. I have them in all my amps (except for my 1968 Princeton where I managed to squeeze in a delicious Celestion Blue). The Italian production Jensen P8R is another fine speaker choice and is certainly cheaper (in Australia) than the Weber option, but to MY ear the Weber sounds better. I am happy to see you prefer the RI Jensens. It means you have ears and don’t simply follow the speaker fashion. Vive la difference!

[@TheVoluntariast]

@@theguitaramptech Interesting. Thank you for your reply. I am not even sure I trust my own ears so I bought 2 Jensens reissues and 2 Webers and recorded them and too me the Jensens were much better. But as you say, 'to each their own.' Thank you for your interesting video. I have the same amp as well.

[@theguitaramptech]

@@TheVoluntariast That's a perfect solution. You put your money where your mouth is and listened carefully. What could be better for meeting your musical goals?Well done, mate. And congrats on having a gorgeous amp!

[@montygore1200]

Ive noticed in the guitar amp world you call it a long tail pair. In the rf world it is known as a diff pair.

[@jimcatanzaro7808]

Ok it would be out of phase east fix put a switch on it and if it sounds bad switch it most modded guitars actually have this mod installed for different tones also many tubes amps made in America for hifi has a phased switch I have about 4 like that it’s not a big deal in the USA 🇺🇸

[@leiferickson3183]

Hi! An American here (I say Solder with the L because I think it is funny and it makes the people I work with wonder what I am going on about). Dont you use isolated secondaries on your step down transformers, and only bring the ground wire through? I would expect that the Active/Neutral debate wouldnt matter then, or do you connect the neutral through as well as the ground? I'm not trying to be smart, I've given up on that long ago, but I am curious about this.

[@theguitaramptech]

Hi Leif. Good work on your pronunciation! I am not exactly sure what your referring to, so I will answer your question generally and hopefully get the answer you need. Yes, in the "olden days" of American mains wiring there was no difference between Active and Neutral, but today their relative location to the Earth pin defines the polarity. In Aus Brown in Active and its White in North America. The secondary is Isolated in the better Stepdowns, but not in the cheapies. My philosophy is to follow the wiring colour scheme of the amps, but I will always Fuse (first) and switch the Active (White or Brown) while the Neutral goes straight to the transformer.

[@simonkormendy849]

I totally get why people would want to keep amps like this Tweed 5F2A 100% original, given the very high prices they command on the used amp market, but one question I would ask is this, would a person prefer an amp that was 100% original, not quite fully functional, and potentially lethal, or an amp that's maybe 80% original, fully functional, and safe to use?

[@theguitaramptech]

That's a very good question. I ALWAYS ask my customers how that plan to use the amp and if they will be gigging with it. Their answer tells you how to proceed.

[@amoruzz]

What year is your LP Deluxe?

[@theguitaramptech]

My Goldtop is a late Norlin from 1979. The body is a single layer of mahogany. Its the heaviest guitar I own at 10.4lb, but I love the sound of the minihumbuckers and feel of the neck. The black Les Paul Custom you may have seen in other videos is from 1971. Its 9lb. When I Bought it, it had EMGs installed, which I ditched. It now has some beautiful Sliders PAFs.

[@amoruzz]

@@theguitaramptech Very cool, thank's 👍 I had a pancake Deluxe just like your's. I love those gold tops, so much that i removed the pick guard. It was HEAVY. Congratulations 🍻

[@jjsant3250]

Preamp cathode caps may also be leaking DC. Are they 63+ years old?

[@theguitaramptech]

You are certainly correct, jj. However, my brief was to preserve as many original components as possible, and I agree with this principle 100%. I hate it when I see such historically important amps with bright orange caps, or ghastly blue resistors reducing the amp to a Clone of itself. As the custodians of these amps for players of the future, we have a responsibility to keep components as original as possible. An excellent question, jj. I need to be more adamant about this responsibility in future videos. Thank you.

[@bakerwood]

Over here in The States, Many outlets are installed upside down. The Ground should be on top. But so many of our Sparkies just love to see that smiling face and install them wrong... or they're Old Hippies and want to make a Peace Sign.😪

[@theguitaramptech]

Thank you! I have learned something new today. I would never have guessed that. In Australia, our Earth is below the L & N pins.

[@sempercompellis]

120 watter??? that is a bit of an overkill- i have used a 80w weller for years and haven't found a chassis grounding job it hasn't been able to handle.. With that 120 watt gun, you must have a window of about 2 minutes from when it is powering up and before it gets too hot

[@theguitaramptech]

I love it. It can do any job I want. Are you admitting that "you can't handle the power?" Hahaha!

[@Roy-xe9is]

In New York it's pronounced sadda, not solder. I think Tesla wore a cap like that.

[@theguitaramptech]

Good lord! I thought you were going to say Boston people call it SADDA. How cool was Tesla!

[@Roy-xe9is]

@@theguitaramptech . Bostonians would say, "This saddaring ion is wicked haught." Tesla was an antenna to the universe. I grew up near his Wardenclyffe lab on Shoram Long Island. Greatest inventor/cosmologist to have lived.

[@theguitaramptech]

OMG. So close to genius. I reckon some would have filtered through to you, Roy! Thanks mate.

[@Roy-xe9is]

@@theguitaramptech "When wireless is perfectly applied the whole earth will be converted into a huge brain, which in fact it is, all things being particles of a real and rhythmic whole. We shall be able to communicate with one another instantly, irrespective of distance. Not only this, but through television and telephony we shall see and hear one another as perfectly as though we were face to face, despite intervening distances of thousands of miles; and the instruments through which we shall be able to do his will be amazingly simple compared with our present telephone. A man will be able to carry one in his vest pocket." Nicola Tesla--1926

[@theguitaramptech]

@@Roy-xe9is what astounding foresight!

[@grahambambrook313]

Don't get me started on ALUMINUM!!!🥵

[@theguitaramptech]

HAHAHA! I so get it.

[@Tom-th1oy]

I can’t believe you would even take a chance using any of those original capacitors in that amplifier.. Just because the parts are original doesn’t mean you should feel bad about replacing them…. If the caps are shot their shot.. By not replacing them, you could cause more harm to the amplifier. You wouldn’t keep the original oil and air filter in your favorite vintage automobile… Or leave a malfunctioning coil and cracked shorting spark plug wires just because they are original right? Doesn’t make any sense to me at all.. But nice job troubleshooting and replacing/installing the new parts..

[@theguitaramptech]

Great email Tom with excellent points. While I agree with some of your comments, let me clarify some others. Oil in a vintage car is a consumable item and does not make up part of the value of the car. Conversely, original amp transformers are critical, like an engine in a vintage car. Components such as capacitors or resistors are more like the wheels. Some owners like it 100% original while some will put on alloys. I agree with you about replacing capacitors that can damage the amp or the owner. You may have seen me change the main filter capacitor and the coupling capacitor. They are both important for the survival of the amp. As you know cathode bypass capacitors can be removed or added to a preamp tube with no detriment other than changing the tone of that stage. Those are the capacitors that I had left in place. They weren’t shot. They had high ESR values, which is an indicator of approaching end of life. If they died, the amp would just sound a little darker. As the amp tech for the major vintage amp store in Sydney, this amp did not yet have an owner. Would he be a collector who would pass by a heavily worked amp, or is he a gigging musician who wants it quiet and 100% reliable? I have no idea. If the amp is brought in by the owner I ALWAYS ask “how do you intend to use your amp”. All techs MUST preserve the originality of a vintage amp, unless, as you quite correctly said, there is a danger to amp or musician.

[@dwightbehm2886]

Sorry Chris I aced the drivers ed test back in highschool we drive on the RIGHT it's much safer that way. Oh sorry don't teach us english we do not pronounce the L in that word for sauder.. Sorry Chris. Sometimes I get a little tired of the arrogance that comes from Great Britain and a little bit of Australia that tries to shove things down us Americans throats again Chris sorry . I do enjoy your videos just fix the amps and try not to explain the English language I've already been speaking it all my life I'm not going to change it.

[@theguitaramptech]

No worries, Dwight. I hope you realise that it is ALL said in brotherly jest. There is NO arrogance in it. We/I love the little differences that make us unique. What a dull place it would be if the USA sounded like us! After 33 trips to the USA, I love your country and its people. I love the regional accents and the foods. (OK. I don't love the gun laws, and the health care system scares the shit out of me when I visit.) As for driving on the right side of the road, I finally got it after a friend in MD taught me this mantra that I still remember after 30 years: "Right is right, Left is Death".