Let's build an amp! Greg's journey to electrocution

[rayc]

Everything in its place.
Tidy and organised as I'd hope anyone working on a motor or a device would be.
Your logic floors me.
I KNOW that everything should be tested/checked before hand but I'd not have the self restraint.
I'm looking forward to watching a workman - just like as a kid looking through the holes in the boarding around a construction site.

[SweetDan]

...And also learn how to read those goddamn stripes on resistors...

Ha, I cheated. I used this:
https://www.digikey.com/en/resources/co ... ode-4-band

...

This one too (was recommended by in one of the videos by the guy who runs http://www.diyguitarpedals.com.au/):

=> https://samstechlib.com/24614782/en/rea ... olor_Codes

On that site there's also pages to check 5- and 6-band resistors.

[jonny deep]

Ha, I cheated. I used this:
https://www.digikey.com/en/resources/co ... ode-4-band

...

This one too (was recommended by in one of the videos by the guy who runs http://www.diyguitarpedals.com.au/):

=> https://samstechlib.com/24614782/en/rea ... olor_Codes

On that site there's also pages to check 5- and 6-band resistors.

When I were a lad, we had resistor calculators made of card, a bit like these:

https://vetco.net/products/resistor-col ... lator-card

[Greg_L]

Thanks guys.

Maybe it's from building racing engines, where even the slightest miscalculation or micro-inch out of spec means catastrophic destruction, is where I learned to be meticulous with detail. I don't know. It just seems like common sense to me. I think the prep work is always the foundation of a good job done no matter what it is. And since I've never done this before, the prep work to me is extremely important. I don't know enough to just slap an amp together, so I gotta have my shit in order if this is going to work. And since one resistor being wrong or out of spec can be the difference between a great sounding amp and a house fire, I better have this shit checked and verified beforehand. And also, by doing all this first, when the amp doesn't work, I'll know it's probably my own human error instead of a part being wrong. It's easier to check all these parts now and make sure they're correct than to do it once they're all crammed inside an amp chassis.

[muttley]

This one too (was recommended by in one of the videos by the guy who runs http://www.diyguitarpedals.com.au/):

=> https://samstechlib.com/24614782/en/rea ... olor_Codes

On that site there's also pages to check 5- and 6-band resistors.

When I were a lad, we had resistor calculators made of card, a bit like these:

https://vetco.net/products/resistor-col ... lator-card

I still have some of those kicking around at the bottom of draws some place. They used to give them away with electronics mags back in the 70's 80's.... There is prolly an app now...

[muttley]

Thanks guys.

Maybe it's from building racing engines, where even the slightest miscalculation or micro-inch out of spec means catastrophic destruction, is where I learned to be meticulous with detail. I don't know. It just seems like common sense to me. I think the prep work is always the foundation of a good job done no matter what it is. And since I've never done this before, the prep work to me is extremely important. I don't know enough to just slap an amp together, so I gotta have my shit in order if this is going to work. And since one resistor being wrong or out of spec can be the difference between a great sounding amp and a house fire, I better have this shit checked and verified beforehand. And also, by doing all this first, when the amp doesn't work, I'll know it's probably my own human error instead of a part being wrong. It's easier to check all these parts now and make sure they're correct than to do it once they're all crammed inside an amp chassis.

Thats what its about man... Its in the detail. If you spend time on the detail there is way less chance of the whole picture being futzed. Its how I was taught and how I work now. Good enough aint good enough...

[JD01]

I think the prep work is always the foundation of a good job done no matter what it is. And since I've never done this before, the prep work to me is extremely important.

This reminds me of Muhammad Ali - you don't win a fight in the ring on fight night, you win it during the endless hours of gym work and road work.

[Greg_L]

Thats what its about man... Its in the detail. If you spend time on the detail there is way less chance of the whole picture being futzed. Its how I was taught and how I work now. Good enough aint good enough...

Right. There are some things I can't check first. I could apply power to the transformers and check all of the readings from the different taps, but that's pretty dangerous and I'm okay with just assuming they're good. They're brand new, so I feel okay with that assumption even though I know things can be bad out of the box. I don't have a tube tester so I have to assume the tubes are going to be okay. So we'll just see. I feel good about my prep work so far.

Today I'm going to the super-nerd electronics parts warehouse in town and I'm just gonna walk around and see if anything catches my eye that I might need or want. I know I'm going to get some more shrink tubing, grounding eyelets, and some large gauge buss wire for my grounding scheme. I will not be doing the stock Fender brass-plate method. Soldering to that plate will be a pain. I'm going to use either a Marshall style grounding plan, or a "buss bar" that runs along the chassis floor. The preamp stages, pots, and jacks will ground to the buss bar and connect to the chassis far away from the power supply. This will minimize eddy currents and shit that creates noise. The mains power and power supply grounds will ground near the power transformer. The reverb and output tranny will ground near the back of the chassis. This will hopefully negate any ground loops and minimize ground interference resulting in a hopefully dead-quiet amp. Hopefully.

I've also decided to add some external bias test points. That'll be a good feature to have. So I'll need to find some female test lead sockets.

[Greg_L]

This is kind of funny/stupid...

I placed two online orders on friday. One of them is coming all the way from Pennsylvania, the other from relatively right up the road in Dallas.

Guess which one is expected to be here today. I'll give you a hint - the Pennsylvania shipment. Lol. The Dallas package is expected to arrive on Friday. How does something from Dallas take a whole week, but something coming from fucking Pennsylvania get here in 3 days? Silly. I should have just driven to Dallas and picked it up myself.

The Pennsylvania order is more "urgent" though, so I guess it will all work out.

[WhiskeyJack]

SWEEET!!!!!! That is awesome. good on you man. I have a wealth of stuff to get caught up on on the Instagram feed. I'll make a point to get on that this week sometimes and add a few of these to list!!

[Minerman]

+1,000,000 on the prep work....The strat upgrade proved that to me, as usual I went the "learn as I go" route, but I have a much better understanding of what needs to be done, so I learned a few things...Next project will be easier because I'll know a few things do to in advance...

The prep work takes 10x longer than the actual soldering, but it's just as important...

I've been thinking about building a tube driven dirt box instead of buying one, so I'll be watching your progress dude...

[muttley]

This is kind of funny/stupid...

I placed two online orders on friday. One of them is coming all the way from Pennsylvania, the other from relatively right up the road in Dallas.

Guess which one is expected to be here today. I'll give you a hint - the Pennsylvania shipment. Lol. The Dallas package is expected to arrive on Friday. How does something from Dallas take a whole week, but something coming from fucking Pennsylvania get here in 3 days? Silly. I should have just driven to Dallas and picked it up myself.

The Pennsylvania order is more "urgent" though, so I guess it will all work out.

The pups I sent across the pond to miner arrived quicker than some bucker covers I ordered from a place 35 miles away.... Beat that..

[vomitHatSteve]

Cool!

So if you electrocute yourself and die, does one of your kids have your password to post photos?

[jonny deep]

Cool!

So if you electrocute yourself and die, does one of your kids have your password to post photos?

Can't we FB Live it or something? That's how people die nowadays, isn't it?

[muttley]

Cool!

So if you electrocute yourself and die, does one of your kids have your password to post photos?

Can't we FB Live it or something? That's how people die nowadays, isn't it?

Yep, gotta monetize teh gerg demise...

[Bill L]

Can't we FB Live it or something? That's how people die nowadays, isn't it?

Yep, gotta monetize teh gerg demise...

Just think of the traffic that would draw to the website! Talk about publicity.

[muttley]

Yep, gotta monetize teh gerg demise...

Just think of the traffic that would draw to the website! Talk about publicity.

There is prolly a good tribute collab in it too.... "Gotta monetize that fucking gerg demise..."...

[JD01]

Is this similar to what you're building? I played though it this evening. Really nice.

20180430_191923.jpg

[Bill L]

Is this similar to what you're building? I played though it this evening. Really nice. 20180430_191923.jpg

The Pro Reverb is one of the great Fender amps.

[JD01]

Greg, the latest Johan video is a comparison of the circuit diagrams of all the Marshall amps based on the Fender Bassman. Was fucking Greek to me but you'd probably like it.