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

[Greg_L]

Sound clips in the Tone Thread!

[muttley]

Place holder.. halfway down page..

[Greg_L]

I'm just talking about undischarged caps when the power is off ..... almost by definition it can't go thru your heart because you have to short the leads of the cap with your skin ..... butthere is a full-blown OMG reaction about those caps even with power off and I say it's a way overreaction

I went back into the amp today. New power tubes, checked some things out. Still looking good. Power tubes are matched well now and perfectly in spec. I'm gonna put it on my new scope and see if I can make any sense of it.

I was thinking about this today so I checked the filter caps. The first cap still had 250 VDC in it after days of doing nothing. That's enough to give you a solid jolt. Probably not lethal. But it sure didn't discharge much from two day of sitting turned off. Creepy. All of Marshalls discharge way faster than that for some reason.

[Lt. Bob]

some designs have those caps fairly isolated so there's little leakage ...... 250 volts discharged at once'll wake you up .... no way it's lethal from those smallish caps .... there's just no way they can have enough amperage.
You have to have both and amperage is actually a bigger factor.

You can use a Van de Graf generator and pop yourself with an inch long spark of 1,000,000 volts and it will not harm ya'.

The biggest danger IMO, speaking as one who has been zapped by amp innards quite a few times is injuring your hand when you reflexively jerk it back at hyperspeed and slam it into the corner of the chassis.

IMPORTANT NOTE: I am NOT suggesting anyone shove their face on a big cap! Use some common sense to avoid pain .... especially if you're wussy about getting shocked.
I'm not but I understand some folks are really squeamish about it ... even finding the idea of touching your tongue to a 9 volt a frightening idea.
But I don't believe caps in an amp will kill you and a search found zero examples of it happening in guitar amps.

The only amplifier caused death I can find is that guy from Counting Crows I think it was and that wasn't working on an amp ...... that was on stage and I think he was using an Ampeg and if so, the same thing that happened to me happened to him only I didn't croak.
And that was a power switch had got knocked loose and put wall voltage to the ground and thus 110 volts to the strings of my bass so when I went to sing and my lips touched the mic BAM*!*@#@! ...... I was on the floor. It was like someone hit me in the face with a bat.

But getting pooped by a cap ...... I'd prefer not to and am careful to avoid it but I've been around amps and amp techs and worked on amps all my life and I personally don't buy into the fear factor.

[Greg_L]

I've never heard of anyone dying either. You'd have to be really careless with a live amp to get killed. There is a lot of general shock potential though, and I was surprised to see that much voltage still sitting in one cap.

[Greg_L]

This afternoon's project. First full recording with the homebuilt Deluxe Retard.

The Witch.mp3

[muttley]

Nice. More details and breakdown possibly?

[rayc]

COOOOL song and cool tone - different amp sound but it works- well, it ought to given the amount of classic rock using one of the originals.
Is this an original?
Everything is ace - I enjoyed it heaps.

[JD01]

This is excellent mate, and the amp sounds great. Is this an original or a cover? Sounds like a cover but I've not heard it before.

[Greg_L]

Nice. More details and breakdown possibly?

Thanks. Let's see....details....
Left rhythm and lead -
SG with MuttPups G90
Vibrato channel, volume and tones set to about 6
Reverb around 3-4
Marshall 4x12 - Vintage 30
Sennheiser e609 about halfway across speaker, couple inches off grill

Right rhythm -
Hallmark 60 Custom - bridge and neck pickups in parallel
Same amp and cab settings

No EQs or FX in DAW on guitars. That's straight amp to speaker to mic to ears.

The new power tubes and hotter bias really woke this amp up. I liked it with the oddball mismatched tubes, but it's 10000x better with the new tubes.

This was also a funny (to me) little exercise for a first real recording with the amp in action. I wanted to do something simple and quick, but still treat it like a real effort. The difference in volume compared to Marshalls was not lost on me. I had this amp set around 6, and it was pretty loud, but not anything like JCM 800 on 6 loud. Lol. I did still need the isolation tracking headphones, but the pounding mind-shaking loudness was considerably less than a Plexi or JCM 800. That's not exactly surprising, but it was totally noticeable. This amp is still way too loud for an apartment or other volume-sensitive situations. It has no master volume, so it needs to be turned up to get the goods. The best part - it's still working with no problems.

COOOOL song and cool tone - different amp sound but it works- well, it ought to given the amount of classic rock using one of the originals.
Is this an original?
Everything is ace - I enjoyed it heaps.

This is excellent mate, and the amp sounds great. Is this an original or a cover? Sounds like a cover but I've not heard it before.

Thanks gents. Sadly for me, this is not an original. This song was originally by the The Sonics from around 1963-1964. In some schools of thought, this is considered the very first "punk song". Some people say this was the very first "punk band". I don't know. It depends on who or what you define as punk, but this song was sort of one of the first kind of crazy, loud, wild, rambunctious, not really radio ready songs to be made and sold to the masses. The original recording is typical 60s garage band distorted....on purpose. Mine's nowhere near as cool.

I've been covering this song in various bands for about 25 years.
[BBvideo=560,315]https://www.youtube.com/watch?v=hVWAE6n_G4Q[/BBvideo]

[rayc]

Ah, I'm a BIG fan of Strychnine and it's in the red distorted chorus vocal.
It's been covered well by a few Oz bands. I'm not sure about the sax though - it works but...they really shouldn't have reformed and done those dad shows in 2008 etc...
[BBvideo=560,315]https://www.youtube.com/watch?v=xFD1xi5Jzk8[/BBvideo]

[Greg_L]

Ah, I'm a BIG fan of Strychnine and it's in the red distorted chorus vocal.
It's been covered well by a few Oz bands. I'm not sure about the sax though - it works but...they really shouldn't have reformed and done those dad shows in 2008 etc...
[BBvideo=560,315]https://www.youtube.com/watch?v=xFD1xi5Jzk8[/BBvideo]

Yup, strychnine. Good song. Funny stuff. Who the hell sings about strychnine? Lol.

They played here in Houston not too long ago. I didn't go but I know a few guys that did. It was nothing but young hipster types so at least they have the attention of the younger crowd. It wasn't a bunch of baby boomers sitting on stools. That's probably pretty cool for those old guys. That's the ideal, right? An old band keeping a young audience is a win in my book.

[rayc]

Yup, strychnine. Good song. Funny stuff. Who the hell sings about strychnine? Lol.
It wasn't a bunch of baby boomers sitting on stools. That's probably pretty cool for those old guys. That's the ideal, right? An old band keeping a young audience is a win in my book.

They looked a bit ancient & augmented as well. The one thing I disliked about the vids I've seen of them is that the instruments and voice aren't distressed/distorted like on the records. That's a small thing though - if they're still doing & enjoying it.
Strychnine was purported to be an ingredient in good acid & other "trips". I remember it being the "knowledge" in the mid 70s when "black dots" were the preferred drug for parties. I tried it once - pretty spaced out and also a little scary. I don't like being out of control.

[Greg_L]

They looked a bit ancient & augmented as well. The one thing I disliked about the vids I've seen of them is that the instruments and voice aren't distressed/distorted like on the records. That's a small thing though - if they're still doing & enjoying it.
Strychnine was purported to be an ingredient in good acid & other "trips". I remember it being the "knowledge" in the mid 70s when "black dots" were the preferred drug for parties. I tried it once - pretty spaced out and also a little scary. I don't like being out of control.

Th distress and distortion in their recordings is just pushing that old analog gear into the red. I added a little bit of that to my recording with a plug-in, but it's not something I normally do. I like that old sound, but I draw the line at buying tape gear.

[Minerman]

This afternoon's project. First full recording with the homebuilt Deluxe Retard.

The Witch.mp3

Just realized this was even here dude...I'm turning into a hillbilly zombie over here...

Sounds great man, I expect nothing less from you though...You should be really proud of the amp you built Greg, I think it sounds awesome, & your build skills are off the charts dude...

[rayc]

Th distress and distortion in their recordings is just pushing that old analog gear into the red. I added a little bit of that to my recording with a plug-in, but it's not something I normally do. I like that old sound, but I draw the line at buying tape gear.

Yeah, poor technique and lack of experience meant some great sounds were captured.
I like the work of the plug in you incorporated.
I've tried the red line process with portastudios and it occurs BUT on cassette tape it's not as wonderful or "musical" as on a big reel. I did try on a reel player/recorder but it wasn't fab.

[Greg_L]

Just realized this was even here dude...I'm turning into a hillbilly zombie over here...

Sounds great man, I expect nothing less from you though...You should be really proud of the amp you built Greg, I think it sounds awesome, & your build skills are off the charts dude...

Thanks buddy. I'm really happy with it. I'm thinking about another one....

Yeah, poor technique and lack of experience meant some great sounds were captured.
I like the work of the plug in you incorporated.
I've tried the red line process with portastudios and it occurs BUT on cassette tape it's not as wonderful or "musical" as on a big reel. I did try on a reel player/recorder but it wasn't fab.

I used the built-in Reaper "distortion fuzz" plug for the vocals. You have to really fine tune the settings though or it sounds ridiculous.

[WhiskeyJack]

that is awesome Greg buddy. it sounds really good. Cool song too. I had heard that in an old skate video one time sandwiched in between a bunch of punk tunes. It really broke up the flow of a shitty skate vid. I will always remember that song for that.

Whats next on your build list? or is it a secret?

[Greg_L]

that is awesome Greg buddy. it sounds really good. Cool song too. I had heard that in an old skate video one time sandwiched in between a bunch of punk tunes. It really broke up the flow of a shitty skate vid. I will always remember that song for that.

Whats next on your build list? or is it a secret?

Thanks dude.

I don't know what I want to build next. LtBoob had talked to me about doing a little Marshall for him, but I don't know where we're at on that. I'd love to try it.

As for myself, probably nothing. I have seven heads sitting here now. Seven! There's not really another tone flavor out there that I want. Maybe an AC30, but that's not really too high on my list. The only styles I ever want are Marshall tones and surfy Fender tones....and now I have all of that.

For this Fender clone, I still have a few minor things to do. I've investigated the little scratchiness I had before and it got better with the new power tubes and hotter bias. That glassy crunchy breakup is part of the Fender crunch sound though. I checked out other Fenders, new and vintage, and they all do the same thing as mine. Mine was just too pronounced with those bad tubes and probably a bit of newness not broken in yet. It's much better now though. It's really "warmed" up and smoothed out. I've put it on my new scope too and it's really nice. I get a nice clean signal and everything looks as it should as far as I can tell. The crossover distortion is smooth and mostly symmetrical. I'll take some pics or maybe even video of that process next.

And it's been flogged hard. I've run it through the gauntlet of Greg-style volume and recording and it's passed with flying colors. This thing kicks ass!


So....what's next for this amp....I've got it wired for the lower voltage option off of the power transformer. All of my voltages are running lower than specified on the original Fender schematic. Now that I know it works and there's nothing catching on fire, I'm going to switch the PT leads and go full power per the original Fender design. I've got some beefier screen grid resistors for the power tubes and slightly beefier filter caps to handle the increased voltage. This should yield higher headroom and tighter bass response. We'll see.

[JD01]

Try making a dual rec. That would be amazing