My first build Jim 5watt V2.0

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JMPGuitars
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Re: Need ideas for my first build

Post by JMPGuitars »

Tomten wrote:
Fri 03/18/22 4:55 am
Look at my docs for the Lite 2b(ish)
Maybe someone have built this and have a video online ? like a demo or something like that ? It would be interesting to hear the distortion in this amp... :D
A TON of people have built it. Probably hundreds. The Lite 2b is the same as channel 1 on the standard 18W, but with a better tone knob.

Another option, which is very similar in difficulty level (easy), is the EF86 Lite. That will give you a little more distortion, with a little bit of the Vox sound meshed with the Marshall sound.
Here's a demo of an EF86 Lite I made for somebody: https://www.youtube.com/watch?v=dj0RL4XVv6A

Thanks,
Josh
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Re: Need ideas for my first build

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I don't think I am very interested in that particular amp, it seem to simple, I would want mids and treble and bass, as well as possible a gain and/or volume and master volume. But thanks for the advice.. :D

After all, I was originally going to build a SLO 50 or 100, I have the PCB´s for it but I find it to expensive to build right now, and I feel like those 5-10 watt amps are a lot cheaper to build. 150-200 Euros or so. Even thought the SLO have a massive amount of gain I don't want to spend the money to build it, I can get an original JCM 800 for the same price as the build cost of a SLO clone, yeah I know, the SLO costs 3-4000 Euros and should not be compared to a JCM 800, but still the JCM 800 is a great amp.. :D
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Re: Need ideas for my first build

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I was thinking if this amp and schematic are better designed for gain then the Jim schematics ? If so, i might just go ahead and build that instead of messing around with the Jim.. :D
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Re: Need ideas for my first build

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So I recommend using a 470k value for the grid stopper R15, instead of 220k and likewise inserting a 470k grid stopper on V2a. I also recommend changing cathode resistor R13 to 620 ohms, to bias that stage warmer, for a thicker and less fizzy overdrive sound
Also to balance the overall frequency response for guitar,
I suggest changing C2 and c16 to 1uF, with C10 and C12 = 10nf or 22nF (you decide which sounds best to you :) )
As I am a beginner at this.. I have no clue where this is, I mean I know where V2a is but not where I am suppose to put that 470k resistor ?
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Re: Need ideas for my first build

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Tomten wrote:
Fri 03/18/22 7:45 am
I don't think I am very interested in that particular amp, it seem to simple, I would want mids and treble and bass, as well as possible a gain and/or volume and master volume. But thanks for the advice.. :D
In that case, the best amp build for you would be the SuperLite TMB: viewtopic.php?t=24430

Thanks,
Josh
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Re: Need ideas for my first build

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OK, I took a second look at the circuit operation. I don't see indications of blocking, but I think the front end should be cooled off a little bit. You can do that by first replacing C4 in the schematic below with a 470KΩ resistor. C4 actually isn't needed, because coupling cap C3 blocks DC from the previous stage. This change will reduce front end gain by 6dB. Also, leave the 1.5K at the cathode of V2A, but remove the 10uF cap that I suggested earlier. Finally, cathode follower V1B will be more "robust" if R7 is changed to 220Ω. Do this last, it might not be necessary.

This is all part of tweaking a new circuit. My goal here was to provide a means of increasing front end gain. I think you be pleased with this once the values are dialed in.

Jack
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Re: Need ideas for my first build

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TriodeLuvr wrote:
Fri 03/18/22 11:00 am
OK, I took a second look at the circuit operation. I don't see indications of blocking, but I think the front end should be cooled off a little bit. You can do that by first replacing C4 in the schematic below with a 470KΩ resistor. C4 actually isn't needed, because coupling cap C3 blocks DC from the previous stage. This change will reduce front end gain by 6dB. Also, leave the 1.5K at the cathode of V2A, but remove the 10uF cap that I suggested earlier. Finally, cathode follower V1B will be more "robust" if R7 is changed to 220Ω. Do this last, it might not be necessary.

This is all part of tweaking a new circuit. My goal here was to provide a means of increasing front end gain. I think you be pleased with this once the values are dialed in.

Jack
Thank you very much, i will try this.. I am thankful that you took the time to have a second look.. maybe this would be more simple with point to point board instead of a PCB ?
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Re: Need ideas for my first build

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JMPGuitars wrote:
Fri 03/18/22 9:41 am
Tomten wrote:
Fri 03/18/22 7:45 am
I don't think I am very interested in that particular amp, it seem to simple, I would want mids and treble and bass, as well as possible a gain and/or volume and master volume. But thanks for the advice.. :D
In that case, the best amp build for you would be the SuperLite TMB: viewtopic.php?t=24430

Thanks,
Josh
This seem interesting, what Hammond PT and OT can I get for this project here in Europe ?
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Re: Need ideas for my first build

Post by JMPGuitars »

Tomten wrote:
Fri 03/18/22 11:10 am
JMPGuitars wrote:
Fri 03/18/22 9:41 am
Tomten wrote:
Fri 03/18/22 7:45 am
I don't think I am very interested in that particular amp, it seem to simple, I would want mids and treble and bass, as well as possible a gain and/or volume and master volume. But thanks for the advice.. :D
In that case, the best amp build for you would be the SuperLite TMB: viewtopic.php?t=24430

Thanks,
Josh
This seem interesting, what Hammond PT and OT can I get for this project here in Europe ?
https://www.hammfg.com/electronics/tran ... watt-combo
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Re: Need ideas for my first build

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Tomten wrote:
Fri 03/18/22 11:08 am
maybe this would be more simple with point to point board instead of a PCB ?
I'm not sure in this case. The changes are actually pretty minor. The main thing is to be as careful as possible not to damage the board.

Jack
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Re: Need ideas for my first build

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https://www.hammfg.com/electronics/tran ... watt-combo

Are those suitable for not just combos but also heads ? because I don't like combos at all..
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Re: Need ideas for my first build

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Tomten wrote:
Fri 03/18/22 4:56 pm
https://www.hammfg.com/electronics/tran ... watt-combo

Are those suitable for not just combos but also heads ? because I don't like combos at all..
From an electrical point of view, what's the difference?

Thanks,
Josh
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Re: Need ideas for my first build

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From an electrical point of view, what's the difference?

Thanks,
Josh
There would be no difference, I mean if its harder to get chassis for heads to fit a PT made for Combo..
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Re: Need ideas for my first build

Post by JMPGuitars »

Tomten wrote:
Fri 03/18/22 5:05 pm
From an electrical point of view, what's the difference?

Thanks,
Josh
There would be no difference, I mean if its harder to get chassis for heads to fit a PT made for Combo..
Nah, there's no difference. If the mounting is standard, it's standard (the "18 watt" standard is common). You can look at the docs for the transformers to see what the mounting points/dimensions look like.

Thanks,
Josh
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Re: Need ideas for my first build

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I will try to make a BOM list for this SuperLite amp and see how much it will cost to build and where to source most of the components.
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Re: Need ideas for my first build

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So it got a little more expensive with the parts for the suggested amp then just by this kit, about 70 Euro more expensive. I do believe that the kit in the link also is possible to be modded... so if I am going to build a 18 watt amp now I might just order the kit.

https://www.tube-town.net/ttstore/tt-ki ... t-tmb.html

Or maybe I will build one more LOW amp.. :D

https://www.tube-town.net/ttstore/tt-kit-hotlukas.html
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Re: Need ideas for my first build

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Tomten wrote:
Fri 03/18/22 6:31 pm
So it got a little more expensive with the parts for the suggested amp then just by this kit, about 70 Euro more expensive. I do believe that the kit in the link also is possible to be modded... so if I am going to build a 18 watt amp now I might just order the kit.

https://www.tube-town.net/ttstore/tt-ki ... t-tmb.html

Or maybe I will build one more LOW amp.. :D

https://www.tube-town.net/ttstore/tt-kit-hotlukas.html
You can't go wrong with TubeTown..
Great quality and service. High speed deliveries.
But they are nearly out of tubes. I placed a large order of tubes at Jukebox Revival yesterday.. the prices are going through the roof with the Ukraine situation.
I even didn't order 12ax7.. too expensive! I ordered NOS Voskhod 6N2P tubes instead. They have a different heater pinout.. but other than that they're a very good substitute for 12ax7 tubes. And only 7€ a piece!!! That's 1/3 or 1/4 the price of a 12ax7 nowadays
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Re: Need ideas for my first build

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TriodeLuvr wrote:
Fri 03/18/22 11:00 am
OK, I took a second look at the circuit operation. I don't see indications of blocking, but I think the front end should be cooled off a little bit. You can do that by first replacing C4 in the schematic below with a 470KΩ resistor. C4 actually isn't needed, because coupling cap C3 blocks DC from the previous stage. This change will reduce front end gain by 6dB. Also, leave the 1.5K at the cathode of V2A, but remove the 10uF cap that I suggested earlier. Finally, cathode follower V1B will be more "robust" if R7 is changed to 220Ω. Do this last, it might not be necessary.

This is all part of tweaking a new circuit. My goal here was to provide a means of increasing front end gain. I think you be pleased with this once the values are dialed in.

Jack
I have some great news, hurray this last mod i did worked as i wanted to, i think it has alot more gain and now i can have the Volume (gain) at full blast with no problem at all, even if its not over distorted i like to back off the distortion just a little bit so it cleans up a little. The sound out of this amp getting even better if i hook up an EQ pedal infront of the amp. This amp now has that rock sound i was looking for, almost a little like AC/DC type of sound. If i back of the Volume quite a bit i got a perfekt clean tone. So the conclusion from this is that i want to keep it like this, well if there is a mod to make it sound like it does with the EQ but with no EQ then that would be interesting to do. Ohh yeah, i have a impedance switch on the back that i would like to use, i tried but i didnt get it to work properly i think so i just hook up the yellow from the OT that is 8 ohm and use it like that, even though i have several cabs that needs both 8 and 16 ohms..

A big tank you to Jack and all the other of you who made suggestions about modding this amp for more a warmer gain.. Now i am thinking about my next project, maybe another LOW amp..
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Re: Need ideas for my first build

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Bieworm wrote:
Sat 03/19/22 7:42 am
You can't go wrong with TubeTown..
Great quality and service. High speed deliveries.
But they are nearly out of tubes. I placed a large order of tubes at Jukebox Revival yesterday.. the prices are going through the roof with the Ukraine situation.
I even didn't order 12ax7.. too expensive! I ordered NOS Voskhod 6N2P tubes instead. They have a different heater pinout.. but other than that they're a very good substitute for 12ax7 tubes. And only 7€ a piece!!! That's 1/3 or 1/4 the price of a 12ax7 nowadays
The 6N2P is an excellent tube. I have some saved, and I somewhat regret not using them in the last amp instead of 12AX7. I suspect the Ukraine situation is going to permanently change the status quo of tubes and tube amps.

Jack
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Re: Need ideas for my first build

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Tomten wrote:
Sat 03/19/22 8:19 am
I have some great news, hurray this last mod i did worked as i wanted to, i think it has alot more gain and now i can have the Volume (gain) at full blast with no problem at all, even if its not over distorted i like to back off the distortion just a little bit so it cleans up a little. The sound out of this amp getting even better if i hook up an EQ pedal infront of the amp. This amp now has that rock sound i was looking for, almost a little like AC/DC type of sound. If i back of the Volume quite a bit i got a perfekt clean tone. So the conclusion from this is that i want to keep it like this, well if there is a mod to make it sound like it does with the EQ but with no EQ then that would be interesting to do. Ohh yeah, i have a impedance switch on the back that i would like to use, i tried but i didnt get it to work properly i think so i just hook up the yellow from the OT that is 8 ohm and use it like that, even though i have several cabs that needs both 8 and 16 ohms..

A big tank you to Jack and all the other of you who made suggestions about modding this amp for more a warmer gain.. Now i am thinking about my next project, maybe another LOW amp..
Glad it worked out! Is that the setting you're using for the EQ? You're really emphasizing the lower midrange with that. It might be possible to modify the TMB controls more toward that type of response, but it would take some work with the simulator. I'll take a look at it if time permits.

Jack
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