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Offline makingnoise88

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Questions about gage of wire.
« on: April 28, 2016, 12:37:06 pm »
I hope its okay for me to post this here!
I'm going to be working on my next amp build and instead of building from a kit I want to build from scratch!
I"m going to building a princeton reverb and then mod it.
So any advice on scratch building and types of resistors and capacitors would be very useful.
Also I wanted to know what the best gage of wire to use would be? Also solid vs stranded.
I want to use aircraft grade teflon wire and I love the look of a super clean amp where each wire is bent to go a certain direction, I'm assuming that is solid core wire. I do know I need a shielded wire for a couple of spots but I'm not sure exactly where.
Any help is greatly appreciated!


Offline Ed_Chambley

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Re: Questions about gage of wire.
« Reply #1 on: April 28, 2016, 01:10:06 pm »
Shielded wire at the inputs.  I try to use stranded everywhere and the stranded I use is PTFE (Teflon) and I get it from APEX JR.  It is pretinned.  I use Metal Film Resistors and in a Princeton Order the Jupiter Caps Doug Sells here.  Really cant go wrong with them.  You will only need them in the signal path.  Use less expensive caps in the tremolo and reverb where the signal is not present.


I prefer stranded because if one strand breaks, I still am connected.  In single strand if one breaks you are done.


If using a Turret board, bring you under board wires all the way through the top and bend them down the side.  Saves you ass since you plan to mod the amp.  You under board wires will not fall out.


I like the cap can that os 40-20-20-20 and use the 40 in the first reservoir.  Tightens the Bass.  Not really a mod as I plan it this way.


If oyu really want Princeton Tone, use the Princeton Output Tranny as the early saturation will be present.


Also I use a heat stripper for wire.  Works great on teflon.  They are pricy, but in the long run will cost you less if you continue building amps with teflon wire.


Here is a link to the wire stripper.  I bought a heavier built one off ebay, but this one works fine:
http://www.techni-tool.com/768ST010?gclid=CJTHofT0scwCFUg8gQodt2kHjg&s_kwcid=AL!2966!3!59637447381!!!g!142253650581!&ef_id=VwLBHAAAAaD4Jjon:20160428180051:s


Good luck and share your build progress and you will get assistance along the way.


Seems we are turning into the Princeton Forum.  Great amps IMO. 


Also consider changing the Tremolo cap values half and will make a swampy type and will still be plenty fast enough.  A 12AU7 in the verb socket gives more adjustment and consider replacing the 1 meg in the reverb circuit with a pot for adjustable dwell.  I put the pot in the standby switch hole since I don't normally use standby switches.


However if you feel you want a standby switch, you can just drill another hole.  A lot of guys will use the EXT speaker hole, but I like to have the EXT speaker to plug in different cabs/speaker for different tones for recording.  Also, a Princeton sounds really great atop a old Bassman Cabinet.


I am making a Princeton Reverb head right now and will begin the build in a couple of weeks.  I am really using the circuit and building a Carr Rambler type of amp.


Keep you eyes out for some NOS 6v6 Tubes as they swing the tremolo better.


Good luck.

Offline HotBluePlates

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Re: Questions about gage of wire.
« Reply #2 on: April 28, 2016, 01:33:34 pm »
... Also I wanted to know what the best gage of wire to use would be? Also solid vs stranded. ...

Gage is all about the thickness of the conductor, which is then all about current-carrying capability. Smaller number = thicker conductor.

22ga (and maybe smaller) is plenty for most internal amp wiring. I prefer 18ga for the wiring from the power cord, power switch & power transformer primary. I also tend to use 18ga wire for heater wiring between output tubes (and from the pilot light to the output tube heaters, if I'm wiring a Fender-style amp). I then use 20 or 22ga for all other tube heaters, as well as all other amp wiring.

The Hoffman cloth-covered wire is 22ga solid core, and is plenty. Hoffman also stocks green 18ga stranded, cloth covered wire for heaters. Hoffman's Teflon wire is 20ga stranded; likewise plenty big enough.

Solid core wire stays in place better if you bend & place it. If it's too thick, it can be hard to bend. If you bend it back & forth repeatedly, it will break. Some people choose to use stranded because of the perceived risk to long-term reliability due to solid-core breakage. However, the original Princeton Reverb used cloth covered solid core wire everywhere (except for the 18ga stranded wire from the PT to the output tube heaters). Lot of Fender amps from the 50's and 60's still chugging after 60 years without issues...

Stranded wire is more flexible, so it bends more easily. But that also means it might not stay in place well if you're trying to route the wire just-so. And you have chances of stray strands going in unintended directions, such as when you try to insert a wire into a tube socket solder lug. However, the Teflon stranded wire is fairly stiff for stranded wire, and is a middle ground between typical solid & stranded wire.

... I do know I need a shielded wire for a couple of spots but I'm not sure exactly where. ...

You can use shielded wire if you want, but it's not necessarily mandatory. Fender didn't have any shielded wires in their classic amps.

Usually, you'd use a shielded wire in long runs of wire carrying low-level signals. For a typical blackface chassis, that might be the wire from the input jacks to the 1st tube stage, and perhaps from the Volume control wiper to a tube grid. New builders generally create more problems than they solve by using shielded wire, by having poor execution in keeping the grounded shield away from signal-carrying wires, or by creating ground loops by incorrectly hooking up the shielded wire.

... any advice on scratch building and types of resistors and capacitors would be very useful. ...

You're best advised to get resistors and capacitors of the correct value, and voltage/wattage rating.

Seriously, right parts-values matter more than type. Beyond that, different folks prefer different things. Some will claim a particular resistor type is most-toneful, while others say you should use a different type for less noise. Sometimes cap type makes some amount of difference, other times it doesn't. You could pretty much order any cap or resistor of a given value from the Hoffman site (regardless of specific type), and as long as it has the correct basic ratings, your amp will sound good.

You can always experiment with more expensive tweak-parts later to see how much, if any, tone change you get.


Ed posted while I typed. I don't believe we're saying anything conflicting...

Offline eleventeen

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Re: Questions about gage of wire.
« Reply #3 on: April 28, 2016, 01:41:59 pm »
Here are some thoughts from someone who has never bought a kit (because I have been doing this for 45 years) but has scratch built dozens of amps.


All you really do buying the parts a la carte is to increase your costs and inconvenience. If you enjoy hunting around for parts, fine. If you enjoy paying freight from 4 different vendors, fine. The parts for these things are not like they were when I started out. Every part then was 25 cents and every tube was $1-2 if I didn't have them scrounged from something else.


I would absolutely urge you to add up the costs of 9 tube sockets, 6 quality 1/4" jacks, 9 knobs, $100 worth of tubes, every screw, every parts board standoff, 9 pots.


Ultimately, you want to end up with (I assume) something works RELIABLY and is in a sufficiently rugged cabinet so that you take it to gigs/jams with out it breaking. This means you have to have a fairly real cabinet. Buying them is pricey, maybe 1/3rd the cost of a scratch build. Unless you yourself can do the woodwork, it is my opinion that the ONLY WAY to save money on a build is to buy and adapt a dead solid state Peavey amp for $20 from someone, gut it, and build a PR inside. This is not a piece of cake, there will be metalwork you have to do, but at least the final product will look OK, be covered with Tolex, have a handle, and amp corners. Incidentally, NONE of the pots from a dead Peavey will be of any use in a tube amp, they will be 5000 ohms, 1K ohms, very low values.


I have added up the a la carte prices for all the parts in a Princeton. You can not buy those for the cost of a clean used Princeton and that is with your time valued at zero.


I am just trying to pass on my experience, not to discourage you. You will save zero money buying the parts one at a time and if you don't have pretty much ALL of them, it will not be an amp.


There is no shame in building from a kit. It's IMO the smart way to go. Best of luck to you and again, I mean no discouragement whatsoever.


Finally....do NOT build anything like you are talking about without at dead minimum buying & building it on one of Doug's parts boards. It's simply not worth the effort it takes to work out your own layout and all that.




Offline HotBluePlates

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Re: Questions about gage of wire.
« Reply #4 on: April 28, 2016, 01:55:38 pm »
... Seems we are turning into the Princeton Forum.  Great amps IMO. ...

... I have added up the a la carte prices for all the parts in a Princeton. You can not buy those for the cost of a clean used Princeton and that is with your time valued at zero. ...

Assuming you meant a used Princeton Reverb Reissue...

The original blackface Princeton Reverbs have gone up to stupid-high prices (getting close to $3k). I guess it has been 20 years, but I'd gotten a near-mint '67 Princeton Reverb in the early 90's for $450.

Oddly, the inflated prices for the vintage article also keep the prices on used reissues elevated, and vice versa.

Offline eleventeen

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Re: Questions about gage of wire.
« Reply #5 on: April 28, 2016, 02:06:11 pm »
Thoroughly agree. There are a few silverface (early ones, still AB763) Princetons & Deluxes I see around here for $1250-$1350 but I just can't bring myself to buy them.


When I started doing this, there was not 1 music store in the entire country (and I wandered around on the road for long periods looking for old guitars and such because I WAS on the road as a musician for years and went into every music store and pawn shop I saw) that did NOT have a $125-$150 Deluxe Reverb. Not one. 

Offline Ed_Chambley

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Re: Questions about gage of wire.
« Reply #6 on: April 28, 2016, 02:48:46 pm »
I saw a silverface Princeton Reverb with a hacked up 12" speaker that appeared to be an old Magnavox 12" from the 60's, tolex peeling with one tube getting hotter that hell.  Grill cloth shot and no brand 80's tubes in it. Bottom was molded and the verb was not working. The guy was excited to pay $2200 for this thing.


I got an offer on my Blond Bassman with cab, a real offer, for $4200.  A friend of mine paid $3300 for a 67 Vibroverb I think it was.  And how about this, I have 12 matched 2 box (24 tubes) Xf2 Mullards EL34's and some real GZ34's still in the box.  Honestly the Mullard tubes do sound good, but where can yo crank a pair anymore and if not cranked they sound the same as =C=.


It is insane, but I am keeping all of my stuff a little while longer.  I have no idea why this is going on.  It is like Beenie Babys!!!

Offline Ed_Chambley

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Re: Questions about gage of wire.
« Reply #7 on: April 28, 2016, 03:05:06 pm »
11Teen I get where you are coming from, but it is a hobby.  I remember my first real scratch build where I made everything.  I started with a old 50's RCA tv because I liked the look of the cabinet.  Mid Century Modern.  I flipped it over so the controls would be on top and took the legs off.


Then I made a Chassis and drilled it backwards and had my input next to my power tubes.  Made a new chassis and simply built a 5F4 which I still think is an overlooked tweed amp.  I have since built a replica of the 2, 10 'V" front.


Anyway, when I finished with this build I was absolutely giddy.  There are a lot of things to spend money on like dope and liquor, but to me anyone wanting to create an amp from parts is admirable.  After a while of collecting parts and learning it becomes much cheaper to build an amp.  Like now I can probably build 15 with stuff I have around.

Offline eleventeen

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Re: Questions about gage of wire.
« Reply #8 on: April 28, 2016, 03:37:42 pm »
I hear ya, Ed, and I agree. But you and I and many others here, we can not imagine what it would be like to source every single part in an amp, every screw, every standoff, every knob, every lockwasher. Because we have gathered all that stuff over the years because we know we like to build (and maybe fix) amps (and other stuff) and we do not mind having a few caps extra or maybe even a whole parts drawer full of caps. Thus, we no longer have the immense frustration of having to gather every single atom needed for a build and missing a doodad here and this clip over there.


I had laid off building for many years, but I moved in with my elderly folks in their final years to take care of them and I needed something to distract me. I kind of had to start from scratch, I had no resistors, no old trannies, no tubes, no nothing. And it was massively frustrating because I did not have 6-32 screws, hell, I didn't even have a bench.


What I *did* have was my old silverface PR and silverface DR and blackface Pro rev, all of which were in serious need of the standard recap, so I could at least buy a huge pile of parts and starting hacking away at them.


Even then though, cheapskate that I am, if I wanted to build something from scratch.....I STILL think I would have bought a kit.   



The other thing us grizzled veterans know is: It ain't an amp until it's done and debugged and dehummed. It's an expensive pile of parts you can't use for much of anything until that last solder connection.


Offline Ed_Chambley

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Re: Questions about gage of wire.
« Reply #9 on: April 28, 2016, 04:09:33 pm »
I hear ya, Ed, and I agree. But you and I and many others here, we can not imagine what it would be like to source every single part in an amp, every screw, every standoff, every knob, every lockwasher. Because we have gathered all that stuff over the years because we know we like to build (and maybe fix) amps (and other stuff) and we do not mind having a few caps extra or maybe even a whole parts drawer full of caps. Thus, we no longer have the immense frustration of having to gather every single atom needed for a build and missing a doodad here and this clip over there.


I had laid off building for many years, but I moved in with my elderly folks in their final years to take care of them and I needed something to distract me. I kind of had to start from scratch, I had no resistors, no old trannies, no tubes, no nothing. And it was massively frustrating because I did not have 6-32 screws, hell, I didn't even have a bench.


What I *did* have was my old silverface PR and silverface DR and blackface Pro rev, all of which were in serious need of the standard recap, so I could at least buy a huge pile of parts and starting hacking away at them.


Even then though, cheapskate that I am, if I wanted to build something from scratch.....I STILL think I would have bought a kit.   



The other thing us grizzled veterans know is: It ain't an amp until it's done and debugged and dehummed. It's an expensive pile of parts you can't use for much of anything until that last solder connection.
Oh yea! There are many times I have answered a Craigslist ad only to arrive to find someone has ordered a bunch of stuff wanting to build an amp.  Even have bought kits that have been messed up.  It is not easy as it looks.


I do like to do conversions like you mention and did one just the other day.  It was an old crate 15 reverb SS amp a friend had and he had put one of those little Weber Alnico speakers in it as he was trying to get it to have a better tone.  You know, the particle board box with the spring reverb inside a chassis.


It had 5 pot holes in the front so I made him a point wired AC4 with a TMB tonestack and a master.  Of course I had the Iron and sockets and that is all I needed, well that and a little hookup wire.  Truthfully  I hated to see if go as it did make a great practice amp.


Now his wife is complaining to me.  He wanted an amp he could use anywhere in the house instead of only having amps in his playing area.  I told her he already had it and she said the old one he had doesn't have what we call (meaning guitar players) a sweet spot and his new amp has a sweet spot. :l2:


Yep, it is hard for me to imagine not having parts around or even tools, but as I think about it I really do have a lot of funds tied up in this stuff.

Offline makingnoise88

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Re: Questions about gage of wire.
« Reply #10 on: April 28, 2016, 04:19:58 pm »
Thanks for all the help.
Really good stuff here.
I'll keep you guys posted!

Offline makingnoise88

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Re: Questions about gage of wire.
« Reply #11 on: April 28, 2016, 04:23:01 pm »
Also what are some good resources for learning to read schematics?
I'm totally new to this and want to under stand where signal flows and all and as of now I have very little knowledge or schematics or how to lay one out.

Offline MoparWade

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Re: Questions about gage of wire.
« Reply #12 on: April 28, 2016, 04:44:16 pm »
What is your knowledge level of circuits and passive components?
Fast Cars and Loud Guitars

Offline makingnoise88

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Re: Questions about gage of wire.
« Reply #13 on: April 28, 2016, 05:47:40 pm »
little to none haha.
I actually just bought myself to read schematics today! In-between replies. That being said I'm still fumbling around and trying to figure out why certain things to to certain places but I'm slowly getting it.
I've built a 5f2a kit and now that its done I'm going back over the schematic and really trying to understand signal flow and where everything is going.

Offline MoparWade

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Re: Questions about gage of wire.
« Reply #14 on: April 28, 2016, 05:56:50 pm »
I think you're on the right track. Study the ways that capacitors and resistors work separately then do some research on high and low pass filters made from those two components. Once you've got that down then study the grid leak, grid stopper, cathode and plate resistors, specifically you want to understand why they are there and what changing their values will accomplish. I think once you understand all that stuff you'll find that you have a much deeper understanding of how these circuits work. A good resource on YouTube is Uncle Doug's Tube Amp Bootcamp it's about 30 videos.
Fast Cars and Loud Guitars

Offline MoparWade

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Re: Questions about gage of wire.
« Reply #15 on: April 28, 2016, 06:06:55 pm »
 :BangHead:

Forgot the most important part, the tubes. Learn what the types of tubes are and know how they work.
Fast Cars and Loud Guitars

Offline makingnoise88

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Re: Questions about gage of wire.
« Reply #16 on: April 28, 2016, 08:59:28 pm »
Thanks so much! ill be looking into that right now!

Offline eleventeen

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Re: Questions about gage of wire.
« Reply #17 on: April 28, 2016, 10:35:47 pm »
I would say http://www.aikenamps.com/index.php/white-papers and http://www.valvewizard.co.uk are just about the most comprehensive "all in one place" spots to cover basic electronics information in bite-size chunks, particularly from the audio amp standpoint. Get that info under your belt and you would know more than all but a handful of folks on this board, myself included.


note 1: It is not especially or even at all necessary to know all that information.


note 2: You could know not a single iota of that information and copy a Deluxe Reverb part for part and assuming you wired it correctly, made decent solder connections, used correct (or close) parts, and powered it up correctly, you would have an electronic device that sounded an awful lot like a Deluxe Reverb. 


note 3: The intellectual knowledge of the stuff at those sites is not particularly connected with ones troubleshooting ability, which is to detect a fault, to construct a thesis about what is wrong that could be causing the problem you observe, testing to see if your theory of wrongness is correct, deriving a solution, then testing whether that particular solution will cure the problem. The key to being adept at troubleshooting is experience with many examples and I know of no way to simulate that.
 

note 4: You could be the reincarnation of Nikola Tesla and Thomas Edison (that would probably generate some internal dissonance)  and if you wire the thing wrong or have bad parts or >>mismarked parts<< the thing won't work no matter how smart you are.


note 5: Even though a schematic diagram depicts the same circuit as a layout drawing, a schematic is absolutely a different thing than a layout diagram, particularly in the case of high gain amplifiers where "lead dress" eg; the proximity of this wire to that wire can have a giant effect on hum and noise.



Once you get that much under your belt, any particular area you wish to explore further, there are tons of other resources. As usual, when you are a newb, you don't even know what questions to ask. Those 2 resources I listed are plenty, plenty and you'd be doing fine to know 1/10th of what's in them.





Offline Ed_Chambley

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Re: Questions about gage of wire.
« Reply #18 on: April 29, 2016, 08:32:31 am »
The way I began understanding was I had an older person who owned a TV and Audio repair shop.  I would work around the shop in my spare time cleaning up and such.  We made a deal if I did that he would show me about repairing and reading schematics.


Since I have learned much from Sluckey about signal paths.  I suggest going to Uncle Doug on youtube and watch.  Watch everything.  Some things may be over your head, but will not be very shortly.  He is a wonderful teacher.
https://www.youtube.com/watch?v=n9hZRLbI6BU

Offline turtle441

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Re: Questions about gage of wire.
« Reply #19 on: April 29, 2016, 09:23:26 am »
Also what are some good resources for learning to read schematics?
I'm totally new to this and want to under stand where signal flows and all and as of now I have very little knowledge or schematics or how to lay one out.
Not specific to a Tweed Princeton, but check out Rob Robinette's site:
https://robrobinette.com/5F6A_Modifications.htm

and

https://robrobinette.com/5e3_Modifications.htm

If you scroll 3/4 of the way down the page on the bassman page past all of the mods to the "How the Bassman Works" section, there's a great little segment that traces the signal path through a tweed bassman.  Similar .gif up top on the 5e3 page.  Should get you a little closer to understanding the signal path, fairly easy flip from there to your tweed princeton.
« Last Edit: April 29, 2016, 09:28:22 am by turtle441 »

Offline HotBluePlates

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Re: Questions about gage of wire.
« Reply #20 on: April 29, 2016, 10:31:13 am »
... there's a great little segment that traces the signal path ...

This is good, but will be misleading (or need to be unlearned) as a novice tries to understand more about electronics and how amplifiers work. Especially because everything is directly or indirectly in the "signal path" (but it may take a lot of background to prove the truth of that statement).

That's because the yellow path drawn is essentially where voltage inputs are applied to a stage, or voltage output are taken from the stage and applied to the next. It does not show the currents pulled by each individual tube stage; and how the Ohm's law relationship among current, resistance and voltage translates those varying stage currents into varying voltage outputs.

Ground is in the signal path. The power supply is in the signal path. Cathode resistors, and bypass caps and filter caps are in the signal path.

BUT... that page is a start, and not unlike a way I learned some basics about radio a long while back. I would recommend adding NEETS (at least modules 1-4, then modules 6, 8 and perhaps 9) as a good foundation.

The challenge is it's too much info to capture in any one source to teach you basic electricity and electronics, then also how tubes work, and also how they're applied in a guitar amp (which is a narrow subset of tube electronics). If you only read the "guitar amp stuff" because it's more directly interesting, you could later use some incorrect reasoning to apply some of the "guitar amp half-truths" to understand a new situation, and have trouble sorting it out. I myself took years note being able to wrap my head around what turned out to be very simple ideas, because I started with a poor foundation of guitar-specific and incomplete information.

 


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