Of course you can clip a preamp circuit by feeding enough voltage into it. Turn down the volume control and hammer the input will clip the first stage. A master volume amp can get everything before the volume control to clip before the outputs do. But if you max out the volume control and increase the volume from your guitar the preamp and the PI will have enough drive to clip the power tubes. As said before, if your preamp is clipping before your power amp (insert 'with your volume control turned up') there is something wrong with your amp.
when i turn the volume up to 6 the power amp starts to clip a bit
when i turn up to 7 - the preamp also clips + the power amp clips more
i dont want the preamp to clip - i only want the power amp to clip
so then you might say "just leave the volume at 6"
no i want all the clipping i can get from the power amp when turing everything up to 10 - at the same time i do not want the preamp to clip
i am talking about small adjustments - and i want it.
i have never seen any amp that do as i am asking for here
Probably a good time for you to let us know what amp you are talking about rather than talk in general terms.
ok - well i wanted to know if i could have someone make an amp for me with 6V6 in the PI and EL34 in the PA - or if somebody has made it already.
so it was just a general inquiery.
when giving the examples as i did before i was talking about my - marshall super lead, marshall super bass, fender super reverb, gibson ga20, teisco(something)
so it was just a general inquiery.
when giving the examples as i did before i was talking about my - marshall super lead, marshall super bass, fender super reverb, gibson ga20, teisco(something)
I did a bass amp using two 6V6s driving a pair of 6L6s via an interstage transformer. Why? Just fer fun. 6V6s heater current is on par with preamp tube's, so no worries there either. 6V6 costs about the same as 12AX7, less than 6SN7s, and I wanted better than average drive. Why? Why not.
Turns out the bassist loves it.
I know I'm not the only one done it. So yeah it's been done. Not sure any commercial circuits like that out there tho.
Turns out the bassist loves it.
I know I'm not the only one done it. So yeah it's been done. Not sure any commercial circuits like that out there tho.
Any modern tube guitar amp will clip when hit with a hot pickup and everything set on 10. Just exactly where this clipping takes place depends on a lot of things. Often stages, especially preamp stages will compress first, then distort, long before hard clipping. Attempting to determine what's distorting by ear is impossible. Someone would need to examine each stage with a scope while you playing your guitar in the usual manner was connected to its input.
Many amps are designed such that all stages enter the compress - distort area around the same time with everything dimed. Adjusting the three typical level controls will alter the balance of distortion. To move the distortion to the latest possible place in the chain, you dime everything on the amp and dial back the guitar's volume control.
I have never seen such a thing, and I made a lot of crazy amp designs in my younger days. Even if such an amp existed there is no guarantee that it would do what you want unless it was designed and tested with your guitar, pickups, and playing style in mind.
All output stage distortion / clipping is not created equal either. The speaker / guitar / player combination affects the output stage heavily. The presence control on a Marshall attempts to influence this interaction. Every guitar speaker is different, as is each guitar / player. A guitar speaker's resonance is usually within the frequency range of guitar notes. An amp that clips heavily with one speaker and guitar player may clip gently or not at all with a different speaker and player.
Many amps are designed such that all stages enter the compress - distort area around the same time with everything dimed. Adjusting the three typical level controls will alter the balance of distortion. To move the distortion to the latest possible place in the chain, you dime everything on the amp and dial back the guitar's volume control.
I have never seen such a thing, and I made a lot of crazy amp designs in my younger days. Even if such an amp existed there is no guarantee that it would do what you want unless it was designed and tested with your guitar, pickups, and playing style in mind.
All output stage distortion / clipping is not created equal either. The speaker / guitar / player combination affects the output stage heavily. The presence control on a Marshall attempts to influence this interaction. Every guitar speaker is different, as is each guitar / player. A guitar speaker's resonance is usually within the frequency range of guitar notes. An amp that clips heavily with one speaker and guitar player may clip gently or not at all with a different speaker and player.
cool - since it was a bassplayer and there where only 2x 6L6 - i can imagine the person liked to drive it ?
so - did it work the in the way im asking about here = no drive in the preamp, and a lot of drive in the power amp ?
im a pro player - and i promise i could tell you from playing any amp for 2sek.
in my marshall - the preamp distortion is very compressed - a bit similar to ex a Boss OD pedal. where as the EL34´s have the crunchy sound with less compression.
you can also say the preamp drive sounds like Slash
the power amp drive sounds like Townsend
you can also clearly hear the difference in a phase inverting tube - it is more muddy than anything - almost like a fuzz
In which amp. You listed a lot. And for a pro you could use capitals for the beginning of sentences and for 'I' as in you. Up to this point I had no idea if I was talking to a 14 year old or not. Not being critical, just the impression one would get reading the posts.
It is easy enough to give you as much drive as you want,
You see the 20k resistor above the output tube? Change it to 10k. Take the next 10k resistor and hook it up to the left of the 20k position. If you want you can do the same to the next filter stage. Basically get rid of your cascaded filter voltage drops and you would have the maximum voltage available to run the stages at.
It is easy enough to give you as much drive as you want,
You see the 20k resistor above the output tube? Change it to 10k. Take the next 10k resistor and hook it up to the left of the 20k position. If you want you can do the same to the next filter stage. Basically get rid of your cascaded filter voltage drops and you would have the maximum voltage available to run the stages at.
Warning. I am typing on my tiny phone and dont always use correct symbols, capitals, or whatever. Sometimes i do and sometimes I don't. Little teenage nittypickies may get offended.
Well the amp is only about 30-40watts out of a pair of 6L6GCs. The idea was getting vintagy and imitate old school designs which had sensible power levels. And the guy likes some dist with his bass. But to be honest it is the clean sounds he likes the most. I have no idea if that amp is any better (dont think so) than others with more standard PI/driver tubes. But the PA's tube grids can go a little pos and no blocking dist.
If driving outputs hard is ur thing I think tubelab's MOSFET bufferd driver is up ur alley. And untill u try it may or may not be what u really want. Have u tried it?
Up until this point I had no idea of the technical capabilities of the OP. This forum usually deals with the ideas and circuits available to someone who wants to DIY their own amp, although there probably are some people here who would build an amp for sale.
I am an electrical engineer and I promise you that I have made, and will continue to make amps where that is not possible. I do not doubt that you may be able to hear the different tones produced by the different circuits in the usual amps with some 12AX7's feeding a pair of typical audio output tubes since they all have similar sonic characteristics.
I make most of my amps today using oddball tubes that do not sound like a 12AX7. Many use a pentode in the gain stages, or even a pair of pentodes for the splitter. I have also made a push pull amp that did not use a PI at all. I did not like it, but it can be done. It's called a self split output stage.
Back in the 1980's I made, and sold several amps that used two different output tubes. The smaller version used a 6V6GT and a 6L6GC, while the bigger version used an EL34 paired with a 6L6GC or a 6550. They had a unique sound that nobody recognized, and therefore was in demand.
The easiest path to get there from here would be to find a clean amp that uses a 6V6 or two in the output stage, then either swap out it's OPT for a suitable driver transformer, wire a second OPT up to the amp's output backwards, or tap the 6V6 plates with a pair of capacitors for drive signal. You could then use it to drive the grids out of a pair of output tubes.
If you want someone here to build an amp for you, then good luck......If you are here asking for ideas, then you may find then, but be prepared to do some of the work yourself.
Hi guys
When I say, that Im a pro player, and I list some of the amps I use - I am not trying to come off as a total d# - I just thought it would be nice for you to know, since that Im new to this group, and so you can understand why I, some times, do not get all the tech specific language.
And - well yeah - as a tech, Im totally a 14 year old (or less)
In this Thread, my intention was only a general question on the use of 6V6´s.
As it turned out, you have given much more information, than I thought I needed. So I really appreciate that.
I definitely want to to try and do some of these things myself, that you have advised. For some things though, I might need to hire someone here in DK, where I live, to do the more risky stuff. But for that, it is really helpful, to have heard the opinions of experienced tech professionals, enthusiasts and experimentalists first.
So with the DIY stuff - Im getting there...
A a teen, I would use to take the speaker output of one amp and run it into a power amp input, of another amp (with a load in between) - and then back to the first amp again (in a split, also going to the speaker), and make feedback loops. With an attenuator, I could even put Wah´s, Pitch Shifter etc. in between. I freaking love the sounds I would get. But now a days, I dont do that anymore. I am trying to learn the proper way of doing these things.
Tubelab_com - sounds interesting. Is there anywhere, one can hear some of your experiments.
Regards.
When I say, that Im a pro player, and I list some of the amps I use - I am not trying to come off as a total d# - I just thought it would be nice for you to know, since that Im new to this group, and so you can understand why I, some times, do not get all the tech specific language.
And - well yeah - as a tech, Im totally a 14 year old (or less)
In this Thread, my intention was only a general question on the use of 6V6´s.
As it turned out, you have given much more information, than I thought I needed. So I really appreciate that.
I definitely want to to try and do some of these things myself, that you have advised. For some things though, I might need to hire someone here in DK, where I live, to do the more risky stuff. But for that, it is really helpful, to have heard the opinions of experienced tech professionals, enthusiasts and experimentalists first.
So with the DIY stuff - Im getting there...
A a teen, I would use to take the speaker output of one amp and run it into a power amp input, of another amp (with a load in between) - and then back to the first amp again (in a split, also going to the speaker), and make feedback loops. With an attenuator, I could even put Wah´s, Pitch Shifter etc. in between. I freaking love the sounds I would get. But now a days, I dont do that anymore. I am trying to learn the proper way of doing these things.
Tubelab_com - sounds interesting. Is there anywhere, one can hear some of your experiments.
Regards.
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I want to start this post by saying that I am not trying to offend anyone.
That being said, I am always wary when a "Guitar Guy" starts asking about building tube amps.
Often they are after a certain "tone" without having enough actual knowledge to know how to actually achieve that goal.
How may amps have you actually built? Simply owning a tube amp (or many) does not mean that you have the essential knowledge of how they actually work.
Often I feel that they are fixated on a particular tone or sound that they would like to achieve without really knowing from where this "tone" comes from.
What you are looking for is not an "off the shelf" product. Maybe it would be best to start by gaining some good basic knowledge of tube amps and how to get what your looking for by building your own. I can reccommend "Building valve amplifiers" By Morgan Jones. That will do more for you than asking on a forum for others to tell you what to do to get what you seek.....
Again, no offense, just some advice🙂
That being said, I am always wary when a "Guitar Guy" starts asking about building tube amps.
Often they are after a certain "tone" without having enough actual knowledge to know how to actually achieve that goal.
How may amps have you actually built? Simply owning a tube amp (or many) does not mean that you have the essential knowledge of how they actually work.
Often I feel that they are fixated on a particular tone or sound that they would like to achieve without really knowing from where this "tone" comes from.
What you are looking for is not an "off the shelf" product. Maybe it would be best to start by gaining some good basic knowledge of tube amps and how to get what your looking for by building your own. I can reccommend "Building valve amplifiers" By Morgan Jones. That will do more for you than asking on a forum for others to tell you what to do to get what you seek.....
Again, no offense, just some advice🙂
I get it - thanks. I will do more research. I thought I had a simple question here - but I guess it turned into a hive. Cheers.
Check out that book though.... Morgan Jones is one of the best books I have ever bought on Valve Amplifiers... I have read it maybe 20 times and always keep it on hand when designing a new amp😉
This is one document I point people new to people getting their hands dirty inside amps https://www.ax84.com/p1/AX84_SE_Builders_Guide.pdf
It is for single ended amps but all the information is valid for push-pull amps. For relatively simple amps that mainly rely on output tube distortion look at the basic Marshall 18 Watt and Fender Tweed amps such as the 5E3 and 6G3 Deluxe.
A place I go to look at schematics. Fender – Ampwares
One thing I like about Fender schematics is that they sometimes give the voltages of the stages, helps in understanding how they work and what they are capable of, as in signal level.
Reading tube datasheets is a good source information along side the circuit information. Now with the internet thing being popular, we have tube calculators. You can plug in different parameters and see what the result is.
Triode Calculator Hosenlander
Or the back of a napkin methode. Designing Common-Cathode Triode Amplifiers
More fun to be had but best to get a basic understanding of the circuits first. Not a bad place to check out. How to design valve guitar amplifiers
Get through the list on the left and you should be able to decipher most amps.
It is for single ended amps but all the information is valid for push-pull amps. For relatively simple amps that mainly rely on output tube distortion look at the basic Marshall 18 Watt and Fender Tweed amps such as the 5E3 and 6G3 Deluxe.
A place I go to look at schematics. Fender – Ampwares
One thing I like about Fender schematics is that they sometimes give the voltages of the stages, helps in understanding how they work and what they are capable of, as in signal level.
Reading tube datasheets is a good source information along side the circuit information. Now with the internet thing being popular, we have tube calculators. You can plug in different parameters and see what the result is.
Triode Calculator Hosenlander
Or the back of a napkin methode. Designing Common-Cathode Triode Amplifiers
More fun to be had but best to get a basic understanding of the circuits first. Not a bad place to check out. How to design valve guitar amplifiers
Get through the list on the left and you should be able to decipher most amps.
Especially as most of us (both DIY and players) forget that half* the tone comes from the speaker.
*yes, it's more complicated than that - speaker/amp interaction is also about half the tone
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