Cascading gain stage with a fixed level

[flemingmras]

But there will always be the kid that just has to have that Marshall script logo on the front if his amp.

Hey! I'm one of those "kids"! lol

However I just build the Metros and install the logo myself on my own amps.

Anymore, when you buy a Marshall, you're definitely paying for the name. A rock band's backline just does not look right without the Marshall script logo on the amplifiers...I full heartedly believe that. But as Obama says...maybe it's time for a "change".

When Jim dies, I wish one of the cloners would buy his estate and all rights to the name and start building Marshalls like they used to...get rid of all the Valvestate and MG garbage.

[Structo]

But there will always be the kid that just has to have that Marshall script logo on the front if his amp.

Hey! I'm one of those "kids"! lol

However I just build the Metros and install the logo myself on my own amps.

Anymore, when you buy a Marshall, you're definitely paying for the name. A rock band's backline just does not look right without the Marshall script logo on the amplifiers...I full heartedly believe that. But as Obama says...maybe it's time for a "change".

When Jim dies, I wish one of the cloners would buy his estate and all rights to the name and start building Marshalls like they used to...get rid of all the Valvestate and MG garbage.

Oh I know, me too!
It is a great logo isn't it?

Yes, one can only hope that Jim Marshall's legacy continue.
I saw a video where I think it was his son that took the person shooting the video on a tour of the factory.
Hopefully his son is conscious of more than just the bottom line.

[novosibir]

I want to illustrate my point here---
There are guys on this forum who just pissed off their wives and spent 1500.00 on an amp kit and a big box of parts show up I remember that "Oh shit" feeling and you can tell it in their post. But they are paying customers who are told this forum will help them.
And it will, it helped me! I know I might have asked a really dumb question, but if this was my first build and I got replies like you need book knowledge before you go poking around in an amp you'll get yourself killed or they just want to be told how to do it or dont respect the science ( I am an audio engineer and I dont mean a computer geek I can actually align a 2" tape machine) I would send that kit right back to Metro.

Just read this post here and must say, that I'm really afraid about that I can realize, that you haven't understood anything of what I've tried to bring you to mind!

I could read a post of a guy, who obviously even isn't familiar with Ohm's law - but this guy intends to build an apparatus with lethal voltages everywhere inside this apparatus! Keep in mind, that building a tube amp is some more, than just complete a puzzle or drawing a picture after numbers - and this absolutely necessitates some basic knowledge about electronics and some experience with tube amps at all! But a guy, who doesn't know at least about Ohm's law IMO doesn't have neither electronoc knowledge, nor experience with tube amps! Hence my recommendation: "to first read some books"!

That wasn't a joke and wasn't an affront, it's just been my way to try to save your life and to keep your wife her husband!

You've pissed off your wife, as you've spent 1,500.00 on an amp kit - and shure, you now do have the aim and the motivation, to complete it - knowledge or not! But have you been thinking just once about, how much you'd have been pissing off your wife, if you only once would have tried to hold the amp's chassis with one hand and would have been touching the B+ with the other? 450...500V straight through your heart..... NO, don't think so! You don't have the µ of a chance to get off of this! Your will only is sending microvolts into your nerves, to move your muscles - but the B+ holds against this, with hundrets of volts! Who will be the winner?

And yes, this forum respectively the guys from this forum are helpful! Very helpful sometimes! No need, to use the psycho method! But we are helping people, who are able to build their amps with their already existing level of knowledge and experience and maybe later then are running into problems with hum, squealing, redplating, static noise, popping, hiss, aso. aso. But this forum isn't a school for electronics, beginning with the 1-st class!

Don't expect from me, that I'm helping someone, to kill himself by accident! And for people w/o any knowledge, Metro is offering to complete the kit for just 400 bucks! That's much less than the contributions to a life insurance over the years - and moreover it keeps your wife her husband, that's again much more than instead of to give your wife some money in the case of.....

Larry

[flemingmras]

I want to illustrate my point here---
There are guys on this forum who just pissed off their wives and spent 1500.00 on an amp kit and a big box of parts show up I remember that "Oh shit" feeling and you can tell it in their post. But they are paying customers who are told this forum will help them.
And it will, it helped me! I know I might have asked a really dumb question, but if this was my first build and I got replies like you need book knowledge before you go poking around in an amp you'll get yourself killed or they just want to be told how to do it or dont respect the science ( I am an audio engineer and I dont mean a computer geek I can actually align a 2" tape machine) I would send that kit right back to Metro.

Just read this post here and must say, that I'm really afraid about that I can realize, that you haven't understood anything of what I've tried to bring you to mind!

I could read a post of a guy, who obviously even isn't familiar with Ohm's law - but this guy intends to build an apparatus with lethal voltages everywhere inside this apparatus! Keep in mind, that building a tube amp is some more, than just complete a puzzle or drawing a picture after numbers - and this absolutely necessitates some basic knowledge about electronics and some experience with tube amps at all! But a guy, who doesn't know at least about Ohm's law IMO doesn't have neither electronoc knowledge, nor experience with tube amps! Hence my recommendation: "to first read some books"!

That wasn't a joke and wasn't an affront, it's just been my way to try to save your life and to keep your wife her husband!

You've pissed off your wife, as you've spent 1,500.00 on an amp kit - and shure, you now do have the aim and the motivation, to complete it - knowledge or not! But have you been thinking just once about, how much you'd have been pissing off your wife, if you only once would have tried to hold the amp's chassis with one hand and would have been touching the B+ with the other? 450...500V straight through your heart..... NO, don't think so! You don't have the µ of a chance to get off of this! Your will only is sending microvolts into your nerves, to move your muscles - but the B+ holds against this, with hundrets of volts! Who will be the winner?

And yes, this forum respectively the guys from this forum are helpful! Very helpful sometimes! No need, to use the psycho method! But we are helping people, who are able to build their amps with their already existing level of knowledge and experience and maybe later then are running into problems with hum, squealing, redplating, static noise, popping, hiss, aso. aso. But this forum isn't a school for electronics, beginning with the 1-st class!

Don't expect from me, that I'm helping someone, to kill himself by accident! And for people w/o any knowledge, Metro is offering to complete the kit for just 400 bucks! That's much less than the contributions to a life insurance over the years - and moreover it keeps your wife her husband, that's again much more than instead of to give your wife some money in the case of.....

Larry

Very well said! I have seen people come to this board with no knowledge of electronics and build amplifiers from what they've learned here. But it wasn't from people "giving them all the answers". It wasn't from people who don't care to learn about electronics and just wanna "go through the motions" of building an amplifier and want us to hold their hand while doing it. It is from people who have a genuine interest in learning electronics and furthering their knowledge of amplifiers.

500 volts is no joke! As a teen when I was first learning this shit I about knocked myself on my ass from a 620 volt B+ supply. It may only be a few hundred milliamps, but there's a shitload of voltage behind that few hundred. People think that it's only the AMPS that get you, but it depends how much voltage you have behind those amps. It's POWER that gets you. Think about your garden hose. You have a lot of water coming out under low pressure. Now put your thumb over it. You now have less water (i.e. AMPS) coming out of the hose, but it's now under a lot more pressure (VOLTS). If the pressure is high enough, you can hose the dirt off your patio with that shit...much more effective than a lot of water under low pressure.

Moral of the story...get some books and read up! It's your life and well being on the line. Losing your wife is better than losing your life!

[papawoofer]

I know Ohms law, although I dont know all of its applications.
I never stick both of my hands in a chasis
I always drain my caps
I always stay away from B+
I am reading and learning alot
I am capible of asking what some consider a dumb question sometimes
You guys think an amp is bad, when we set up for a show we connect to the buildings AC panel with our own AC distribution center (which I have been designing and building for 15 years) one mistake and it will hold you there until you are fried. Of course by law we have to take certain safety precautions.
All I needed was info on how to avoid using a pot, I know I read it here somewhere but couldnt remember where
I hope this eases your minds
Everybodys wife gets mad when you spend 1500.00, but mine is OK

[novosibir]

Yes it's nice, if you do have all the mentioned abilities, but we can't reckon this by a guy, who's asking, how to calculate a voltage divider - because this is the basic of the basic in electronics

Larry

[neikeel]

I had not been involved with this thread until now, I winced slightly when it became clear quite early on that Papawoofer was asking certain questions extending beyond his previous experience and knowledge. I did not post a reply as I was sensitive to making similar comments to those made by the others which might come across as patronising which is not desirable in the General Beginners Section of one of the best fora I have come across.

Most people come here and start by the paint/build by numbers and need clear instructions. Others have electronics experience but no familiarity of valve amp layouts, particularly Marshalls with their oddities and 'deliberate' but serendiptous mistakes

Papawoofer has progressed beyond the first step and can walk safely and quite sensibly asked for help and was advised accordingly by posters here. They were not to know how experienced he was or was not but the questions asked suggested caution and safety is important to us all even those that drink and smoke and do other wreckless activities .

I think more stuff on the Wiki is an excellent idea and I keep meaning to do an introduction on the principles of how a Marshall does what it does and why, from input jack to speaker jack, keeping it simple (as that is what I am in this environment) etc explaining how/why a triode works, what a tone stack does, how the volume/tone contols work how the transformers and output valves work. I have been asked these questions a few times and my texts are old and very generic (my fathers old electrical engineering text books) to refer to.

All stuff that many of us take for granted but would be useful in the wiki, giving references to the relevant texts.

I just need a sabbatical from work/family and gigs

Good luck with the build Papawoofer I have been very pleased with my first 2 in 1 and am working (when I get time) on my next version and have the sketches for my next after that

[flemingmras]

I had not been involved with this thread until now, I winced slightly when it became clear quite early on that Papawoofer was asking certain questions extending beyond his previous experience and knowledge. I did not post a reply as I was sensitive to making similar comments to those made by the others which might come across as patronising which is not desirable in the General Beginners Section of one of the best fora I have come across.

Most people come here and start by the paint/build by numbers and need clear instructions. Others have electronics experience but no familiarity of valve amp layouts, particularly Marshalls with their oddities and 'deliberate' but serendiptous mistakes

Papawoofer has progressed beyond the first step and can walk safely and quite sensibly asked for help and was advised accordingly by posters here. They were not to know how experienced he was or was not but the questions asked suggested caution and safety is important to us all even those that drink and smoke and do other wreckless activities .

I think more stuff on the Wiki is an excellent idea and I keep meaning to do an introduction on the principles of how a Marshall does what it does and why, from input jack to speaker jack, keeping it simple (as that is what I am in this environment) etc explaining how/why a triode works, what a tone stack does, how the volume/tone contols work how the transformers and output valves work. I have been asked these questions a few times and my texts are old and very generic (my fathers old electrical engineering text books) to refer to.

All stuff that many of us take for granted but would be useful in the wiki, giving references to the relevant texts.

I just need a sabbatical from work/family and gigs

Good luck with the build Papawoofer I have been very pleased with my first 2 in 1 and am working (when I get time) on my next version and have the sketches for my next after that

I've already started on the power supply section. Check it out.

http://metroamp.com/wiki/index.php/Cate ... y_Circuits" onclick="window.open(this.href);return false;

I figured this would be the most important part of the amp since the power supply is ultimately where the power fed to your speakers comes from.

http://metroamp.com/wiki/index.php/Cate ... y_Circuits" onclick="window.open(this.href);return false;

Now in regards to this thread I'm gonna have to side with Larry on this one. Papawoofer already did his "paint by numbers" build on his first one. By the second one, especially if he's planning to do this one different, he should be expressing a desire to learn how the thing works, not another "paint by numbers" way to build it. And yes, the voltage divider is the basic of basic of electronics (simple series circuits). After all, a pot is nothing more than a variable voltage divider. When you rotate it, the resistance between the center terminal and one outside terminal decreases while it increases between the center terminal and the opposite outside terminal. By starting with two resistors in series that equal 1MEG ohm when added together, by increasing one and decreasing the other while using two values that still add up to 1M ohm, you're doing exactly the same thing you'd be doing with a volume pot, but with fixed resistors.

Most of the people here that I've seen that have done multiple builds usually do their first one "paint by numbers" style, then by their second one and every one after that, they start catching on and asking questions about how things work rather than wanting a "paint by numbers" method for every build. I think that was the point that Larry was trying to make.

[neikeel]

Most of the people here that I've seen that have done multiple builds usually do their first one "paint by numbers" style, then by their second one and every one after that, they start catching on and asking questions about how things work rather than wanting a "paint by numbers" method for every build. I think that was the point that Larry was trying to make.

I think we all agree then

[papawoofer]

ya know, Larry I dont care if you believe me or not, and you have totally convinced me that I have no business being here or buying products that I will hurt myself with. Friday I will make my final purchase (I have gone this far cant stop now that will definately piss the wife off , hope I dont kill myself though) and very soon I will make my final post, in tribute to George who has brought the DIY spirit to the masses or at least to me, he has really made a dream come true for me and I am forever grateful. Thanks to you guys who have submitted kind and helpful posts. Maybe someday there will be a "Before Beginners" section.

[novosibir]

Amen!