Hello,
I have a Yamaha G100. It has a very weak distortion. I like the fender Bullet distortion. With them both being solid state I could copy the distortion section of 1 and put it in the other I just need help in identifying the sections to mod.
Also if any one can draw me up a schematic of how to wire the foot switches for these amps would be awesome I can't find hardly anything on this amp.
I have uploaded the schematic for the Yamaha hope someone can help me out. Thanks a lot.
I have a Yamaha G100. It has a very weak distortion. I like the fender Bullet distortion. With them both being solid state I could copy the distortion section of 1 and put it in the other I just need help in identifying the sections to mod.
Also if any one can draw me up a schematic of how to wire the foot switches for these amps would be awesome I can't find hardly anything on this amp.
I have uploaded the schematic for the Yamaha hope someone can help me out. Thanks a lot.
No you can´t.
Build/buy a *good* distortion pedal you like and use it in front of the Yamaha *or* add a preamp out to the Bullet and drive the Yamaha with it, effectively using the Bullet as an effects pedal.
Any standard single button mono plug footwitch will be fine to switch channels, which is the "important" function.
A similar one will switch reverb on/off, not that essential.
You may get a 2 button standard footswitch but it will need to end in 2 separate mono plugs instead of the more popular single stereo TRS plug.
Do NOT use footswitches with LEDs because not only they won´t light but also it will interfere with proper operation.
not that the G100 had great sounding distortion but it had lots of it.
if you need help identifying the "section" to mod then i would think you may not be up to task to do what your planning, knowing is half the battle!
if the distortion is truly weak then the mosfets that mute the distortion channel may be defective and are also reducing the gain of that channel, anything is possible with an amp of this vintage.
if you need help identifying the "section" to mod then i would think you may not be up to task to do what your planning, knowing is half the battle!
if the distortion is truly weak then the mosfets that mute the distortion channel may be defective and are also reducing the gain of that channel, anything is possible with an amp of this vintage.
Thanks for the replies.
Build/buy a *good* distortion pedal you like and use it in front of the Yamaha *or* add a preamp out to the Bullet and drive the Yamaha with it, effectively using the Bullet as an effects pedal.
Hmm I am intrigued by your idea of the bullet becoming a pedal and I have several pedals distortion compression overdrive and have tried various combos just not getting the screaming biting sustaining meaty chunk I like. But to be honest I've not really ventured out to taste all the dirt pedals available now. Open to suggestions for a high gain distortion pedal with quiet operation and a nice functioning eq. Prefer it to be a diy but not critical.
not that the G100 had great sounding distortion but it had lots of it.
if you need help identifying the "section" to mod then i would think you may not be up to task to do what your planning, knowing is half the battle!
if the distortion is truly weak then the mosfets that mute the distortion channel may be defective and are also reducing the gain of that channel, anything is possible with an amp of this vintage.
Yeah Ive heard these are great clean amps for a SS but this distortion is just way too weak. And with the " if you need help identifying the section to mod then I would think you may not be up to the task to do what your planning".. no worries its all good with the help identifying I am more than skilled enough to do some mods. I can make circuit boards from scratch from a schematic all the way to the finished working item. My problem is in the whys and some hows of circuits. So again really it 'd be cool if I could find out what components are being used for the distortion and what components I could swap out you know like clipping diodes get more gain with some other part. The mechanical part of diy pedal building is the easiest part for me its the understanding of why and how this does that for this that I'm slow to absorb.
So I ask again if any one could tell me maybe where and what I could change and play with . Cause I'll socket the changed parts until I'm satisfied with it what I get.
Build/buy a *good* distortion pedal you like and use it in front of the Yamaha *or* add a preamp out to the Bullet and drive the Yamaha with it, effectively using the Bullet as an effects pedal.
Hmm I am intrigued by your idea of the bullet becoming a pedal and I have several pedals distortion compression overdrive and have tried various combos just not getting the screaming biting sustaining meaty chunk I like. But to be honest I've not really ventured out to taste all the dirt pedals available now. Open to suggestions for a high gain distortion pedal with quiet operation and a nice functioning eq. Prefer it to be a diy but not critical.
not that the G100 had great sounding distortion but it had lots of it.
if you need help identifying the "section" to mod then i would think you may not be up to task to do what your planning, knowing is half the battle!
if the distortion is truly weak then the mosfets that mute the distortion channel may be defective and are also reducing the gain of that channel, anything is possible with an amp of this vintage.
Yeah Ive heard these are great clean amps for a SS but this distortion is just way too weak. And with the " if you need help identifying the section to mod then I would think you may not be up to the task to do what your planning".. no worries its all good with the help identifying I am more than skilled enough to do some mods. I can make circuit boards from scratch from a schematic all the way to the finished working item. My problem is in the whys and some hows of circuits. So again really it 'd be cool if I could find out what components are being used for the distortion and what components I could swap out you know like clipping diodes get more gain with some other part. The mechanical part of diy pedal building is the easiest part for me its the understanding of why and how this does that for this that I'm slow to absorb.
So I ask again if any one could tell me maybe where and what I could change and play with . Cause I'll socket the changed parts until I'm satisfied with it what I get.
with this situation it's not a case of swapping out components it's a question of re-designing.
when you say the distortion is "weak" i take it as meaning not enough which on a G100 (in proper working order) is not the case. i would agree that sonic quality may not be to your liking.
try back to back led's or diodes(clip/limit circuit) after IC 2 or change the gain of that stage, heck even a different op-amp may get you closer to what your after.
the 2SK30A fet's are likely defective so until your certain it's working properly modding or circuit changes may get you nowhere...
when you say the distortion is "weak" i take it as meaning not enough which on a G100 (in proper working order) is not the case. i would agree that sonic quality may not be to your liking.
try back to back led's or diodes(clip/limit circuit) after IC 2 or change the gain of that stage, heck even a different op-amp may get you closer to what your after.
the 2SK30A fet's are likely defective so until your certain it's working properly modding or circuit changes may get you nowhere...
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Thank You Turk 182 for your reply. I will check the fet's and related components.
The different op-amp you refer to swapping out is it, IC2?
When I say the distortion is weak I mean when turned up to 10 there is very little effect. I'm thinking now that I'll just use pedals for my distortion. I love diy pedals problem is building them and finding out after that its not what I wanted and sound
The different op-amp you refer to swapping out is it, IC2?
When I say the distortion is weak I mean when turned up to 10 there is very little effect. I'm thinking now that I'll just use pedals for my distortion. I love diy pedals problem is building them and finding out after that its not what I wanted and sound
Some Marshall pedals are more than a plain "distortion pedal" and in fact are a full fledged guitar amp preamp channel, complete with gain and master controls, 3 band EQ, the works.
Using one of these is the same as adding a Marshall distortion channel to anoher amp.
You will find on line, at the Pedal Forums, the full project for the Guv´nor, which is the one I suggest you build.
They post the full schematic, iron on PCB design and suggestions for cabinet, graphics, etc.
So build one, guess it´s 90% or more of what you want, and way more practical than modding the Yamaha which will never ever sound like the Guv´nor.
It sounds KILLER.
There are others, but this one is very good.
After some time, you can build another, there are many different projects.
I mean the original, 1992 one, which is basically a "Marshall-in-a-Box" , later they turned it more into "a pedal", hope you get what I mean.
https://www.youtube.com/watch?v=hz0O3v43Gjw
Using one of these is the same as adding a Marshall distortion channel to anoher amp.
You will find on line, at the Pedal Forums, the full project for the Guv´nor, which is the one I suggest you build.
They post the full schematic, iron on PCB design and suggestions for cabinet, graphics, etc.
So build one, guess it´s 90% or more of what you want, and way more practical than modding the Yamaha which will never ever sound like the Guv´nor.
It sounds KILLER.
There are others, but this one is very good.
After some time, you can build another, there are many different projects.
I mean the original, 1992 one, which is basically a "Marshall-in-a-Box" , later they turned it more into "a pedal", hope you get what I mean.
https://www.youtube.com/watch?v=hz0O3v43Gjw
The distortion circuit of Yamaha preamp is easy to locate: The signal path splits in two right after recovery gain stage that follows the tone control circuit. Channel A is the clean channel, channel B the overdrive channel. You can see how it consists of a gain control, gain stage, shunt diode clipper, an overdriven FET gain stage, and output signal level control, respectively.
Fender's distortin is trickier concept because it actually covers almost the entire preamp: It's not just a signal clipping circuit, throughout the entire preamp the signal is deliberately equalized to attain frequency response similar to Fender's tube-based amps, then signal is clipping distorted, and eventually fed to a speaker cabinet emulation circuit, which is either followed by tone controls or integrated to the tone controls. Basically, you can't just separate the clipping part from all this.
So basically omit the gain stage with "Normal Volume" control, the reverb circuit and the power amp and what's left is the distortion circuit of the Bullet preamp. As you see, it's pretty much the entire preamp.
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