Tidy & Neat Wiring - Tips?

[hobageeba]

Hey everyone. I'm about to start my second amp kit build and I'm still very green with this stuff. My first build worked first try and sounds wonderful, but the inside of the chassis is a sloppy mess :o. I've noticed how nice and neat people can get their wiring and I'm wondering if any of you pros have any good advice or tips/tricks for newbies like me. Are there any tricks to straightening and cleanly bending leads? I'm generally pretty anal about making things nice and neat, and it would be really gratifying for me to be able to layout and solder a neat looking board. Any good tips on how to keep the wiring clean and organized? Thanks a lot!

[Scott Auld]

Free bump 'cause I"m all ears on this thread

[teleamp]

A good layout is the key. Take your time, while a neat amp looks good, proper lead dress will yield a better amp. If you layout is well thought out, the lead dress will end up looking nice.

[hobageeba]

Thanks teleamp. The kit came with a punched chassis so the layout is already done for me. As for lead dress, to expose just how green I really am, I wasn't even sure what exactly that meant. I googled "lead dress" and came across some good reading. Here's some for anyone that's interested. It's a bit wordy for me (and probably other newbies) but helpful nonetheless:

http://www.geofex.com/article_folders/lead_dress/lead_dress_in_tube_amps.htm
and...
http://ayanmusic.com/leaddress.htm

And some other threads on lead dress, which I found to be a bit easier to digest:
http://music-electronics-forum.com/showthread.php?p=56170
http://www.tdpri.com/forum/amp-central-station/993-what-makes-good-lead-dress-why.html

Geez, I must've really hit the jackpot of dumb luck with my previous build, as I didn't really even pay attention to what wires sat next to the other and the amp is hum free. The only thing I did right was to twist the necessary wires together. Phew!

I'd still like to hear if anyone has any tips on tidy cap/resistor leads...

[Wakarusa]

Well, tweed amps are simple/easy if you put them in a bigger box. Good lead dress for a beginner in a top control Fender style chassis can be a bit daunting. Especially if you've got fat ol' fingers like me :)

I think the most common mistake for newbies is excessive lead length. There's a temptation to cut the wires long to give you enough slack to work with the lead. Resist the temptation. In the vast majority of cases shorter yields better performance and a tidy build.

Wire is (relatively) cheap so cut an ample amount for a lead, then pre-fit the piece into the amp. From here you can trim as necessary and then solder, or you can solder one end and then trim/strip the other end in place. If you're starting out a good set of wire strippers that you can use in tight spaces can help a lot. If that proves overly difficult, you can use the cloth "push-back" insulated wires until you develop better skills.

Another tip... build the board first. Get it all wired up on your bench where you have room to work. Pre-solder long leads that will run off to tube sockets, power rails, grounds, etc. to the board. Fit the board to the chassis and then trim, strip, and solder your way through the off-board connections. Trying to solder the off-board leads after you mount the board can be a quick path to disappointment.

Most of the other usual tips are available all over the place -- avoid parallel runs of high voltage leads, cross leads at right angles, don't use sharp bends, etc. There's also great information in some of the technical literature (MILSTD/MILHDBK stuff and the old Westinghouse standards/training manuals if you can find them)

[hobageeba]

Thanks Todd, pretty helpful stuff. The amp I'm building is a Princeton 5F2A kit so it may be a bit of a squeeze but I'm confident I can make it work.

John, those are some very neat and tidy chassis! I figured the main answer would be practice practice practice but I had to ask. I have a question about the grounding on the 65 Custom. The instructions in my kit recommend the grounding scheme you have going there; running a wire, running all the grounds to it, then grounding it in a single spot. I wasn't really sure what that would look like, but now I see yours and I know I've seen that before. My question is, how is that propped up like that? Is it just being held by the wires coming off of the pots? Oh, and another newbie question...can you elaborate on the "over the top, and down along the chassis" heater wiring techniques?

[stratman_el84]

One thing that can help make your tagboards/pcb boards, etc look clean and neat is a lead-bending tool as shown here: http://www.mtechnologies.com/tools/index.htm#bender

Cheers!

Strat

[teleamp]

For getting staight leads on your caps and resistors, roll them between two pieces of steel.

[Wakarusa]

One thing that can help make your tagboards/pcb boards, etc look clean and neat is a lead-bending tool as shown here: http://www.mtechnologies.com/tools/index.htm#bender


An alternative is a set of round-nosed pliers (typically used in the jewelry business). The round, smooth jaws make lead bends without sharp corners, diameter reduction, nicking, or marring that you get from pliers with an edged and/or serrated jaw. Because the jaws are tapered you can even adjust the diameter of your bend -- handy for making bends that exactly fit around turrets. Craftsman part #45666 works fine and goes for $10.

[Chrome Dinette]

I do something similar to what the above poster does with solid copper as well.



Lots of neat layout pictures in this old thread:

http://www.thegearpage.net/board/showthread.php?t=176129&highlight=porn

[ClinchFX]

It's nice to see that everybody here agrees that there's no place for hard bends in wires and component leads.

Peter.

[GearHeadFred]

Have your grounding scheme clearly figured out before you start ANYTHING! I am still suffering from that mistake.

[DAB]

I've started using teflon coated wire (TFE) which is very easy to get to stay in place. You can make nice little bends in it on longer run wires and get it to stay in place.

[teleamp]

The order that you wire can help. For instance, doing all of the AC and transformer wiring first. Also, if your doing "laydown" filament wiring, do it after the transformers. Pay attention to the oreintation of the tube sockets so your lead dress will look like the layout you are following.

[Nolatone Ampworks]

I've started using teflon coated wire (TFE) which is very easy to get to stay in place. You can make nice little bends in it on longer run wires and get it to stay in place.

Yes, this is a pretty big one. I'm using Belden solid core and it stays put when you bend it, and it's also forgiving of the soldering iron. It takes a bit more to melt the insulation even though it IS pvc.

[hobageeba]

The order that you wire can help. For instance, doing all of the AC and transformer wiring first. Also, if your doing "laydown" filament wiring, do it after the transformers. Pay attention to the oreintation of the tube sockets so your lead dress will look like the layout you are following.

Thanks, that's a cool tip. Thanks also John for clearing up the over the top and along the chassis filament wiring thing. I guess that was pretty obvious. Ha.

This is straying a bit from the topic, but do any of you guys know of any sites or books (preferably sites) that take a guitar amp circuit and break down each section and explain what and how each of the components affect the sound/function of the amp? I had two 6 hours drives so I took some schematics and layouts and started studying them and trying to analyze what was going on. I started to figure out which parts were the different stages and from reading various articles on the internet, I started to deduct what some of the components are doing i.e. which resistor controls the negative feedback, what a bypass cap across a cathode resistor does, etc. I didn't even know the physical terms/properties of tubes like cathode, anode, grid, triode, pentode, etc. before my little study session. I'm a true newbie, but I'm really trying! Anyhow, if anyone knows of anything like this, it would be HUGE help. Or if anyone wants to take a super simple circuit like a champ and break it down for me that would be awwwwesome :bow Maybe I should start a different thread for this question...whatever.

[Wakarusa]

Probably one of the best places to start is with the generous writings of Randall Aiken. Go to his website (www.aikenamps.com) and follow the "tech info" link. He doesn't break down an amplifier quite the way you want, but he does show the fundamentals the different circuits you'll typically see in a very understandable way.

[hobageeba]

Yup, I've been reading up on his tech info section. I guess it's good critical thinking trying to figure how circuits work on my own...But it sure would help a lot to see it broken down.

[teleamp]

Thanks, that's a cool tip. Thanks also John for clearing up the over the top and along the chassis filament wiring thing. I guess that was pretty obvious. Ha.

This is straying a bit from the topic, but do any of you guys know of any sites or books (preferably sites) that take a guitar amp circuit and break down each section and explain what and how each of the components affect the sound/function of the amp? I had two 6 hours drives so I took some schematics and layouts and started studying them and trying to analyze what was going on. I started to figure out which parts were the different stages and from reading various articles on the internet, I started to deduct what some of the components are doing i.e. which resistor controls the negative feedback, what a bypass cap across a cathode resistor does, etc. I didn't even know the physical terms/properties of tubes like cathode, anode, grid, triode, pentode, etc. before my little study session. I'm a true newbie, but I'm really trying! Anyhow, if anyone knows of anything like this, it would be HUGE help. Or if anyone wants to take a super simple circuit like a champ and break it down for me that would be awwwwesome :bow Maybe I should start a different thread for this question...whatever.

Kevin O'Connor, has an entire line of books that break it all down.

[RedMan]

Neat is cool but proper routing to keep noise/oscillation at a minimum is what's most important

[teleamp]

Neat is cool but proper routing to keep noise/oscillation at a minimum is what's most important


+ One Billion

People confuse "lead dress" with "neat looking", it's not about the look, it's about rules. And when you have one that was built by the rules of proper lead dress and it looks good, it didn't happen by mistake.....it's all about the layout. A well planned layout takes all aspects of the amp into consideration.

[hobageeba]

+ One Billion

People confuse "lead dress" with "neat looking", it's not about the look, it's about rules. And when you have one that was built by the rules of proper lead dress and it looks good, it didn't happen by mistake.....it's all about the layout. A well planned layout takes all aspects of the amp into consideration.

Understood 100%. No one will see the inside of the amp other than me and maybe a couple other dudes who open the amp up in the future. I'm fully aware that the functionality of the amp completely eclipses how tidy the inside of the chassis looks. I've just never really seen or heard tips on tidiness addressed so I thought it'd be interesting to hear if people had any special things they do or don't do.

[Wakarusa]

I dust this pic off every now and again and post it to a new thread :)

Built on a rainy afternoon, looks like a rat's nest, but follows good routing and layout -- also performs flawlessly and is hum-free.

http://www.wakarusaamp.com/tmp_pix/jtm45/234_3432_small.JPG

[drspencer]

......looks like a rat's nest, but follows good routing and layout.

http://www.wakarusaamp.com/tmp_pix/jtm45/234_3432_small.JPG

What are the 'rules' for proper layout/lead dress?

Thanks

[teleamp]

What are the 'rules' for proper layout/lead dress?

Thanks

Properly implemented grounding.
Twist high current carrying wires (filaments, HV secondary).
Do not run signal wires parallel. Cross other signal and filament wires at 90 degree angles and not touching.

To test out which wires are sensitive to placement, make that lead extra long and route it up and out of the way to its quietest position, then take a foot long length of insulated wire and protect one end and make a few wraps around the insulation of the wire you are testing, with the loose end (time to put your other hand in your pocket) touch the terminals of wires that are near or in its path, take note of those wires that add noise and position the lead as needed.

How the tranformers set in relation to each other plays a role in noise too.

[BJF]

Hi,

Yes, I'd agree with that a neat look is not crucial or even necessary and in some cases not even desirable due to how the mechanics need to be layed out, but that there sure are rules for grounding and I can say I have rewired amps with starground to bus ground and reduced hum significantly; and rules for stability with regards to oscillation,which can cause funny things to make the amp work reliably, but that also includes determing the margins and rules for mechanical stability as in if the amp can take the cargo retrieve at JFK airport and can you drop the amp from kneeheight 15 times without anything inside breaking and safety as in can the amp be used safely, including rules for isolation in Volts/mm or inches and mechanical angles and withstand the abuse of musicians,their relatives and children and domestic animals?

Right so then you combine highimpedances, high amplification and low level signals to be processed into higher wattage, and that's just asking for trouble woohoo:crazyguy

Amplification just like that is maybe misnomer as that would imply linear amplification while a guitaramp these days would distort and therefore a guitar amp would be a processor of nonlinear amplification.

I don't think there are any hard rules on how a wire must be bent or how neat a layout must look, but would certainly recognize rules for functionality both on a user level and a circuit level.

I'd recommend doing first a scetch of things that must be set- like you'd want the front and back panel to make sense to a nontechnician and then using the rules to guide the inner construction and mechanical structure and ease of wiring-how neat you then can make that is a matter of your patience.......stressing the point that neat in itself means little..........

Question: would you build an amp to impress people with how it is made or would you build an amp because you think it sounds good and makes mechanical sense?:phones:stir

Have fun above all:drink:band
BJ


Affiliations
BJF Electronics
Sweden
www.bjfe.org (http://www.bjfe.org)
www.mpamp.com (http://www.mpamp.com)

[Wakarusa]

Scour E Bay for chassis pics of old Fenders and newer booteek amps and copy from what the pros do.
http://i10.photobucket.com/albums/a122/RockinDaddy/5E5A/DSCN0895.jpg





Not to pick nits, but I wouldn't run the plate and grid leads right next to each other on that first gain stage :).

[Wakarusa]

Doing so tends to lessen sub harmonics, especially those you hear when playing double stops. An old tech taught me that one, said he learned it from Nashville amp techs. Run 'em as close together and parallel as possible without them touching, so long as you're not building a high gain amp. It works s'all I sayin'. So, there is a reason for that.

Let me start by saying that if you like the way the amp sounds and behaves, then there's absolutely nothing wrong here. Just discussing layout and lead dress here and what kinda results it can lead to.

Running the grid and anode leads in parallel can cause a bit of NFB on the stage since their signals will be out of phase here. I can even see where the effect would be more pronounced at frequencies where the guitar pickup (or the amp) has a bit more gain. Whether this attenuates sub-harmonics in particular I couldn't say for sure. I can, however, see where this could lead to a bit more noise in the amp if you manage to couple power supply noise between the leads. The real sin would be if the grid from the first stage ran in parallel with the anode from the second stage -- in phase and therefore more likely to lead to oscillation or instability (something not happening here, but something I've seen done).

Finally, if by "sub-harmonics" you're talking about unwanted very low frequency response, the typical frequency response of the stage should take care of it, otherwise I'd think a more reliable solution would be in the stage's design -- set the low -3dB point wherever it needs to be by tweaking the cathode circuit(s) or values of interstage coupling caps or even adding a touch of NFB in the cathode circuit
.



a quick side note -- if you want intentional, but known/designed, NFB in the very first stage, cathode feedback is a bit better behaved than anode feedback because it eliminates the need for a blocking cap on the grid.

[CitizenCain]

This is straying a bit from the topic, but do any of you guys know of any sites or books (preferably sites) that take a guitar amp circuit and break down each section and explain what and how each of the components affect the sound/function of the amp?

I found this site to be very enlightening when I started to get into amp building, http://www.freewebs.com/valvewizard/index.html

Not that I'm all that in to it, I've got one rebuild under my belt and another in progress, but it sure made sense of a lot of things.

THe first section in particular, Triode Gain Stage, really goes into basics of stage design. It's all contained in a PDF that's linked there, http://www.freewebs.com/valvewizard1/Common_Gain_Stage.pdf

[hobageeba]

I found this site to be very enlightening when I started to get into amp building, http://www.freewebs.com/valvewizard/index.html

Not that I'm all that in to it, I've got one rebuild under my belt and another in progress, but it sure made sense of a lot of things.

THe first section in particular, Triode Gain Stage, really goes into basics of stage design. It's all contained in a PDF that's linked there, http://www.freewebs.com/valvewizard1/Common_Gain_Stage.pdf

Wow that's a great site, I booked marked it right away. I'll have to sit down and really read all that stuff later. Thanks!

And what's FTB stand for?

[CitizenCain]

FTB? Where do you see it?