New amp build finally started. JTM45 with KT66.

Looking at the work involved, I am glad that I did not embark on this project now. I am so OCD that everything takes me twice as long as anyone else. It would take forever for me to complete a build like @SG John is working on.
For me, that's the beauty in it! I love taking my time when doing stuff like this. If you're in a hurry, then move on to what you know. But the first time you put one of these amp kits together and get it to run properly, you're probably going to get hooked.
 
For me, that's the beauty in it! I love taking my time when doing stuff like this. If you're in a hurry, then move on to what you know. But the first time you put one of these amp kits together and get it to run properly, you're probably going to get hooked.

Totally get it....I love making things, but I get too deeply involved in projects.

I needed an amp ASAP for work, so I had to move fast...
 
Music takes on a different perspective when its your sole source of income.

Distraction...

When I was going through the Gibson purchase fiasco - between 2016 and 2018, my frustration and my search took up a tremendous amount of my time, cutting into my 4 hour per day minimum practice schedule.

I was, instead, researching, reading, complaining, etc., and practicing less and less. Then, I embarked on designing/patenting/trademarking my own headstock/name/guitar line...another huge distraction, then i almost started building an 18 watt Mojotone amplifier kit, which would have been another huge distraction.

My first love is music, but it is also my sole source of income, and I have to carefully balance having adequate time to support all my musical obligations.

Its stressful at times, but TBTH, I have a wonderful life...


I was thinking in the differences of how we approach music, and they are from very different sides of the coin. Maybe not even the same coin, or currency. I have always played in original bands and tried to develop my own voice. I found humbucker guitars worked for me, and tried several amps until I got my JTM45 back in 1989. Up to that point, I had a couple of SGs, a Les Paul, and a Firebird. The first SG and the Firebird I sought out. Another SG and Lester found me. I got pointed in their direction, they were nice, and I had cash around to buy them. With the exception of maybe three guitars, I was always shown something and was asked "Hey, are you interested? This would be a good match for you." If it sounded good, was cool, I liked it, and I had the money, then yes I probably bought it. It was just another wrench in the toolbox as far as I was concerned. I think that since I wasn't concerned or obsessed with a particular sound or windmill, I was able to enjoy their peculiarities. Even now, I know what all my stuff does. I've had most of it for years. I'll play different guitars and amps at practice, just to get them some exercise. Then, when we play a gig, I may have something completely different, and it only takes me a minute to dial it in.

It could be that since I had being a machinist to fall back on, I never worried about "Making It." I wasn't obsessed with making sure I was going to make X amount of dollars this week at various gigs. And, if the BS is too much, I can walk away and start something new. That made it fun to grab stuff I didn't really need, but thought it would be cool.

Honestly, I could never be in a cover band, or work sessions. The thought of covering the guitar sounds of eight or twelve completely unrelated bands, and play music I hate to make money does nothing for me. I tried it for a while. For the fun stuff like Allman Brothers, Grateful Dead, Bevis Frond, Big Head Todd, and other acid/jam stuff, I could get away with being me as long as I kept all the hooks in place. Then, if we played Alice in Chains, Soundgarden, Bush, Stone Temple Pilots, or other commercial stuff, we would get berated for not playing it just like the record. I just tell them, "you get up there and play 50 songs with no cheat sheets."

It also reminds me of something my old guitar teacher said to me. "Talent isn't playing what you like. Anyone can do that. True talent is playing off of charts or playing music you hate, and doing it better than others. That's talent." I always remembered that when band mates would introduce new songs. I would always try them. Even if everyone else thought they were crap. I would always stick up for the person introducing a new song, and insist we give it a chance. Once everyone puts their stamp on it, it may not sound or feel that same anyway.

How you can do daily it amazes me. My wife's uncle was in a wedding band for 30 years. It was his only job, and they were one of the most sought after acts for weddings. They could and did play anything that was requested when hired. As much as I try new stuff all the time, I could never be in a GB coverband. Kudos.

Just so you know, I'm not a cheap hoarder. Wildlife and Rainforest charities see a lot of money from me and my wife. We give it when we can. In a couple of years, the pedals might start making their way out the door. Maybe some other stuff too, but for now I'll enjoy them. They owe me nothing.
 
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Looking at the work involved, I am glad that I did not embark on this project now. I am so OCD that everything takes me twice as long as anyone else. It would take forever for me to complete a build like @SG John is working on.


For me, that's the beauty in it! I love taking my time when doing stuff like this. If you're in a hurry, then move on to what you know. But the first time you put one of these amp kits together and get it to run properly, you're probably going to get hooked.

I take it from the same point of view as Greg. When I have the time, I work on it. Some unexpected stuff came up this evening, and helping my wife was more important. I’ll jump on it again tomorrow or Wednesday. Right now, as much as I would love to dive in, there are more important things going on.
 
I was thinking in the differences of how we approach music, and they are from very different sides of the coin. Maybe not even the same coin, or currency. I have always played in original bands and tried to develop my own voice. I found humbucker guitars worked for me, and tried several amps until I got my JTM45 back in 1989. Up to that point, I had a couple of SGs, a Les Paul, and a Firebird. The first SG and the Firebird I sought out. Another SG and Lester found me. I got pointed in their direction, they were nice, and I had cash around to buy them. With the exception of maybe three guitars, I was always shown something and was asked "Hey, are you interested? This would be a good match for you." If it sounded good, was cool, I liked it, and I had the money, then yes I probably bought it. It was just another wrench in the toolbox as far as I was concerned. I think that since I wasn't concerned or obsessed with a particular sound or windmill, I was able to enjoy their peculiarities. Even now, I know what all my stuff does. I've had most of it for years. I'll play different guitars and amps at practice, just to get them some exercise. Then, when we play a gig, I may have something completely different, and it only takes me a minute to dial it in.

It could be that since I had being a machinist to fall back on, I never worried about "Making It." I wasn't obsessed with making sure I was going to make X amount of dollars this week at various gigs. And, if the BS is too much, I can walk away and start something new. That made it fun to grab stuff I didn't really need, but thought it would be cool.

Honestly, I could never be in a cover band, or work sessions. The thought of covering the guitar sounds of eight or twelve completely unrelated bands, and play music I hate to make money does nothing for me. I tried it for a while. For the fun stuff like Allman Brothers, Grateful Dead, Bevis Frond, Big Head Todd, and other acid/jam stuff, I could get away with being me as long as I kept all the hooks in place. Then, if we played Alice in Chains, Soundgarden, Bush, Stone Temple Pilots, or other commercial stuff, we would get berated for not playing it just like the record. I just tell them, "you get up there and play 50 songs with no cheat sheets."

It also reminds me of something my old guitar teacher said to me. "Talent isn't playing what you like. Anyone can do that. True talent is playing of of charts or playing music you hate, and doing it better than others. That's talent." I always remembered that when band mates would introduce new songs. I would always try them. Even if everyone else thought they were crap. I would always stick up for the person introducing a new song, and insist we give it a chance. Once everyone puts their stamp on it, it may not sound or feel that same anyway.

How you can do daily it amazes me. My wife's uncle was in a wedding band for 30 years. It was his only job, and they were one of the most sought after acts for weddings. They could and did play anything that was requested when hired. As much as I try new stuff all the time, I could never be in a GB coverband. Kudos.

Just so you know, I'm not a cheap hoarder. Wildlife and Rainforest charities see a lot of money from me and my wife. We give it when we can. In a couple of years, the pedals might start making their way out the door. Maybe some other stuff too, but for now I'll enjoy them. They owe me nothing.

Please understand that I'm only messing with you guys about hoarding. I am in no way seriously berating you guys for your guitar collections. Sometimes, I just interject what I do or what I think about certain things, but in no way am I trying to influence anyone.

In fact, I think I have more gear right now than I have ever owned before!!!

Schecter Hellraiser C1FR
Jackson San Dimas FR
Von Herndon Double Neck
Black Handmade Les Paul Custom
Ibanez Bass

(2) DSL40C 's
(1) Blackstar ID Core 100 (DAW only)
(1) 1999 Marshall MG50CRD (Back Up)
(1) Fender Rumble 40 (DAW only)

I almost can't believe it when I look at the list!!!!

Now (2) DSL40C's are being replaced with (1) Origin 50H and custom 2x12 cabinet, so that's downsizing some!!!@!!!
 
I'm happy with my life and my work in music. I like how every day is something new and different. I sometimes play songs that I don't really like, but I still find a way to make it interesting and fun

Every day is like a party. BS'ing around the coffee maker with fresh hot donuts, making jokes, drawing silly cartoons or making funny memes and posting them up, there's so much laughter and off-color humor that I'm excited to get to the studio everyday, just to see what will happen next...
 
I take it from the same point of view as Greg. When I have the time, I work on it. Some unexpected stuff came up this evening, and helping my wife was more important. I’ll jump on it again tomorrow or Wednesday. Right now, as much as I would love to dive in, there are more important things going on.

I admire you guys!!!!!!

I can't stop once I "lock on" to a project, so through buying a working amp, I can tunnel vision on playing (earning a living) instead of tunnel visioning on soldering.
 
Got a bit slammed with real life stuff, and needed to do some work on my motorcycle in preparation of impending garage repairs. As stuff arrived that I neglected to purchase, I took care of other things. Just did a bit more. As soon as a 1K 5 watt Ohmite resistor arrives, the turret board will be done. I cleaned up the heater wires and the input jack. After the turret board is done, I’ll add the AC cable and 16 uF filter cap. Almost ready to fire up.

5248E624-CECD-489E-837D-5C30856940F0.jpeg


282D7857-726B-452C-AAEE-ADCF111410F1.jpeg

Also did some work on the Hawgosaurus. Packed the steering stem bearings, new front tire, packed the wheel bearings and installed new seals. Waiting on the brake pads to arrive.

B43286F2-5128-49F3-9CCB-8C5EFB4605C5.jpeg
 
Got a bit slammed with real life stuff, and needed to do some work on my motorcycle in preparation of impending garage repairs. As stuff arrived that I neglected to purchase, I took care of other things. Just did a bit more. As soon as a 1K 5 watt Ohmite resistor arrives, the turret board will be done. I cleaned up the heater wires and the input jack. After the turret board is done, I’ll add the AC cable and 16 uF filter cap. Almost ready to fire up.

View attachment 49162


View attachment 49163

Also did some work on the Hawgosaurus. Packed the steering stem bearings, new front tire, packed the wheel bearings and installed new seals. Waiting on the brake pads to arrive.

View attachment 49164

Nice work on the amp, as usual.

Points awarded for use of Wurth CU800 or 1100...
 
Where's that resistor going to?
That goes between the 27K resistor and 8uF capacitor to the left of the Philips .1uF caps. There are two empty turrets anxiously awaiting its arrival.
I'll just jump in here SG John, to make sure you get this part of the circuit assembly done correctly.
Ok, the resistor that goes between the 27k (NFB series) resistor & the 8uf bias supply filter cap (filling the two empty turrets) should be an 8k2/1W resistor.
The 1k/5W Ohmite should be mounted between the empty turret on the "valve socket" side of the board & pin 6 of V4.
I'll post a couple of pics (taken from the Marstran Historical Data site) to help with this.1600806277828378433376304893063.png
Above we can see the 8k2/1W/10% (grey, red, red, silver) carbon composite resistor mounted "across" the board between the two turrets mentioned, while the 1k/2W/10% (brown, black, red, silver) carbon composite resistor is mounted "flying" between the board (actually soldered to the lead of the 8k2/1W resistor rather than the turret) & pin 6 of V4. Note, the 470 ohm screen grid resistors mounted on the sockets are not original in this pic.
Here's a couple more pics16008062489969060048985044299662.png
Again, the 1k resistor is soldered to the lead of the 8k2 PI HT dropper/decouplers resistor
1600806147084995917526415057311.png
Here the 1k resistor appears to be soldered to the turret rather than the lead of the 8k2/1W resistor.
It's important to get this right. With a 1k resistor in the place of the 8k2 resistor, V3, V2 & V1 will be supplied with a higher HT voltage than they should.
It is good to see that you followed an actual JTM45 schematic & included this 1k resistor in the screen grid supply. Not many do when building JTM45's.

Note in the pics that the two turrets on the "ground" side of the two 8uf bias supply filter caps (+ end of the caps) are linked together by a solid wire "above" the board. This should then be grounded (below the board) at the "main" ground point.
I don't see the two turrets being linked by the solid wire yet in your build (maybe you've done this below the board). Be sure to "ground" these two turrets.

Your build is looking good.
What value is the Vishay Dale metal film resistors in the bias circuit?? I "may" have a 1/2 watt Piher in this value, so as to maintain the "period correct" theme. If I do I'll mail it to you. Cheers
 
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It is good to see that you followed an actual JTM45 schematic & included this 1k resistor in the screen grid supply. Not many do when building JTM45's.
This is so bizarre to me. What is the purpose of this "flying" resistor?

What value is the Vishay Dale metal film resistors in the bias circuit?? I "may" have a 1/2 watt Piher in this value, so as to maintain the "period correct" theme. If I do I'll mail it to you. Cheers
Awesome... (This is the second time today that I have used the word "Awesome")... :cheers:
 
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