Power Amps.

[pinkphiloyd]

I've studied Merlin's pre-amp book extensively.  I've also found several great free online resources over the years discussing pre-amps and tones stacks, so I feel like I have a pretty good handle on that stuff.  Information on power amps seems to be a little harder to come by.  I understand the basics, the "big picture", if you will, but I'd like to get into being able to design my own.  I'm thinking about pulling the trigger on the 'The Ultimate Tone' books, but I thought I'd ask if anybody can point to anything more appropriate that I might check out first.  The cheaper the better.  I have a lot of irons in the fire at the moment.

[eleventeen]

Without specifying particular sites, most, if not the overwhelming majority of push-pull output stages are modeled on the so-called "Williamson" circuit design. There are lots of sites that discuss this famous and widely used circuit. Maybe searching for same would be a good start.

[MakerDP]

You already have Merlin's book for phase inverter info.

The Ultimate Tone Vol 2 will help you with power amp design, both SE and PP. TUT vol 3 will also give you a lot of examples of what the more popular amps out there do, but is a little lighter on the theory.

[pinkphiloyd]

Excellent, thanks!

[PRR]

> the overwhelming majority of push-pull output stages are modeled on the so-called "Williamson" circuit design.

The Williamson is super-deluxe and generally over-the-top for guitar work.

> I'd like to get into being able to design my own.

Plagiarize, plagiarize, plagiarize. Copy, steal, clone. Both Tube Factory suggestions and commercial amplifiers. (Look at DIY amps, but remember the average DIY-er is not a mature and battle-scarred design veteran.)

Essentially everything worth doing has already been done. Don't sneer at this wealth of proven plans. If there is anything left to do, it will come out of the features and failings of what has come before.

A design on paper is not worth a cent. (The paper was, before you scribbled it.) If you want an amplifier, *build* an amplifier. Remember solder goes both ways, on and off, so it does not have to be perfect the first time. Keep your iron warm.

[TIMBO]

I have very little technical knowledge when it comes to design an amp and as PRR said its already been done and when it is all said and done its very subjective.

Try not to get too bogged down into all the BLAH BLAH BLAH as it does get confusing.

You tube is the best place to start to find the sound you like, then research the amp, BORROW their circuit, heat up your iron and build your amp.

This process WILL get you hooked and wanting to build more, cause ALL amp sound different. Then after tireless years of searching for your ULTIMATE amp you will have a good idea of what you want and it will probably turn out to the one you look at on you tube way back when.

[kagliostro]

If I can suggest you a book

Guitar Amplifier Power Amps, by Richard Kuehnel

http://www.ampbooks.com/mobile/books/power-amps/

Also if may be difficult it is really a must

Franco

[MakerDP]

,

Essentially everything worth doing has already been done. Don't sneer at this wealth of proven plans. If there is anything left to do, it will come out of the features and failings of what has come before.

A design on paper is not worth a cent. (The paper was, before you scribbled it.) If you want an amplifier, *build* an amplifier.

Sorry gotta call B.S. there.

If you want to learn how to *build* an amplifier then build amplifiers. If you want to learn how to *design* amplifiers then read, experiment, read, try something else, read some more, build some more. There are MOST DEFINITELY new ideas to be found out there.

[pinkphiloyd]

If I can suggest you a book

Guitar Amplifier Power Amps, by Richard Kuehnel

http://www.ampbooks.com/mobile/books/power-amps/

Also if may be difficult it is really a must

Franco

 

I've built numerous amps at this point.  I've tweaked existing and designed my own pre-amps.  But to this point I've only been able to copy power amps.  And that's not really good enough for me; the learning is the fun part.  Even if it only leads to minor tweaking of existing designs to get a little closer to what I'm looking for.

[MakerDP]

I've built numerous amps at this point.  I've tweaked existing and designed my own pre-amps.  But to this point I've only been able to copy power amps.  And that's not really good enough for me; the learning is the fun part.  Even if it only leads to minor tweaking of existing designs to get a little closer to what I'm looking for.

Sounds like you are on the right track! Now go design the new "game changer!" And if you never end up finding it, have fun with the process. You'll learn a heck of a lot more than the average person who just copies existing designs from this or any other site. 

TUT volume 3 is good for learning how to tweak existing designs. KOC goes through a good number of existing well-known amps, discusses their shortcomings and then offers improved designs and layouts for them. Quite a few of those improvements are in the power amp sections.

[jjasilli]

,

Essentially everything worth doing has already been done. Don't sneer at this wealth of proven plans. If there is anything left to do, it will come out of the features and failings of what has come before.

A design on paper is not worth a cent. (The paper was, before you scribbled it.) If you want an amplifier, *build* an amplifier.

Sorry gotta call B.S. there.

If you want to learn how to *build* an amplifier then build amplifiers. If you want to learn how to *design* amplifiers then read, experiment, read, try something else, read some more, build some more. There are MOST DEFINITELY new ideas to be found out there.

+1 to PRR.  I've said basically the same myself.  There's lots of variation, but it's all been done already -- a long time ago.

[MakerDP]

+1 to PRR.  I've said basically the same myself.  There's lots of variation, but it's all been done already -- a long time ago.

Well that certainly makes it true then...

[Willabe]

There's been a whole lot of people who worked on tube amps for decades, it's already been done.

[MakerDP]

While there has been a lot of clones, IMO, there are a lot of challenges out there.  The down side is there are not many affordable tubes that are new design.

Yup. This field is not like micro-electronics where you can create the next million-dollar kick-starter funded mass-produced techno-marvel with a $35 Arduino and $35 in parts from Radio Shack over the course of a weekend.

In addition to the MUCH higher cost to tinker with designs, add in the deadly voltages that tend to scare your average hobbiest away and the fact that there isn't really millions of dollars to be made which scares large-scale industrial research away.

Is this field STALLED... yes I think it is to an extent for the reasons stated above among others.

Is this field EXHAUSTED... abso-frikken-lutely NOT.

[shooter]

physics departments and electrical engineering departments

In order to find new, I think you gotta come up with new physics or new engineering, to paraphrase PRR, not gonna happen.  I've been toying with the idea of Ic's controlling cathode I in a PA, A micro controller as a variable modulation source, but every time I get out the pieces, I get this twitch, thinking why would anyone want to mix perfectly good technologies together for some sub-par device.
Become the best "your amp here" builder, folks with guitars will notice.

[PRR]

> Is this field STALLED...
> Is this field EXHAUSTED...

We have FORGOTTEN much that has already been done.

Read AUDIO magazine 1948-on. And that's only a fraction of what was going on in power amps (not the best work either).

But I suspect, for most electric guitar work, there is a real magic in the simple design of a high-class pentode radio output stage with a trace of NFB. As you get into fancier plans it becomes "too sterile", you may as well use transistors and lose the weight.

[PRR]

> Ic's controlling cathode I in a PA

MusicMan used Silicon driving the cathodes of big bottles.

They were useful in their day. They were cleaner ("a new sound!") than traditional tubes, in a period when transistor power amps were fragile.

[John]

http://forum.allaboutcircuits.com/


If you want to swim in the ocean of electronic circuits of all kinds.

[jjasilli]

I was reading an old copy of guitar player magazine, and Sampedro of Crazyhorse was talking about an all tube recording studio.  A few posts on building 2"recording equipment would be nice.  I haven't two inch recording equipment since my days as a substitute dj at KTEC in Socorro NM.  (The equipment was on loan from KQEO 830 AM in Albuquerque.)   Then somewhere in one of the old books is an all tube equalizer (16 points).   Haven't seen any posts on all tube equalizers.  While there has been a lot of clones, IMO, there are a lot of challenges out there.  The down side is there are not many affordable tubes that are new design.  Some of the KT tubes of high wattage are an obvious exception.  (Tubes are less than $$$$).  Keep up the good work forum dudes and dudettes.

Definitely take up PRR on his advice to review the old electronic magazines from the '40's - 70's.  There's lots of stuff posted free online.  PRR also posted this awhile back in the Amp Tools section.  I'm in hiatus after reading about a dozen monthly magazine's from the '50's, until I get a chance to make a spreadsheet to cross-reference the articles I like.  It's a wealth of great info, and thanks again to PRR fro posting this.

[shooter]

MusicMan used Silicon driving the cathodes

  I was hoping PRR and the author of Ecclesiastes was wrong
Are they one in the same

[Willabe]

Look at a Music Man schemo and in a couple of Kevin O'Connor's TUT books he goes into SS cathode drive. 

[Ed_Chambley]

Just experiment and have fun.  I will say every time I think of something "new" I eventually find it has been done.  I have a new idea going and having loads of fun with a Zenith Giant with an added shelf holding 2 additional amps.

I can say this tho.  Sometimes taking a EF86 Vox design and building it tubes up in a Marshall style headbox will give you a stable, cool running, best sounding Celestion Blue screaming 15 watter.  Then there are those who want a Fender clean for chords and channel switching to a Marshall for leads.

Maybe tubes have all be run to the point where this is not new, but combining ideas is KEWL, especially when your fellow players check it out.  A great sense of pride.

Then there are those who are artistic and make the most beautiful completed amps and cabinets. 

Thank goodness for simple circuits that sound great.

[Ken Moon]

A good place to start is to just build a nice simple experimenter amp, then you can compare what you read to actual voltages/currents and how they sound to your ears.

A great tube to experiment with is the 6L6, which is a tough tube that is compatible with a wide range of preamp designs and power amp variations, and doesn't suffer from blocking distortion problems that are so easy to accidentally create when using EL84s and 6V6s.

Get a transformer set that will support the 6L6. A 275-0-275 or 300-0-300 with at least 200mA (like the 270HX/272HX from Hammond or an equivalent Edcor) will be perfect, or you can get a replacement PT from almost any 40 to 60 watt Fender, Ampeg or other amp with 6L6s or EL34s. It's nice to get an OT with 4, 8 and 16 ohm secondaries,  so you can use just about any combination of speakers. A 50 watt OT with a primary impedance of 4k2 would be great for the 415V B+ on the Pignose shown below, but anything between 4k and 5k would work.

Get a BUNCH of 5 to 10W power resistors (I like the Vishay Mills resistors, available in 7 watt and 12 watt versions, and some 20uF, 40uF and 47uF filter caps (F&T makes nice radial versions). The power resistors are to dial in the B+ voltages at each node.

Build a straightforward one-channel amp (I think the Pignose G40V is a really great one to start with), using this schematic and board layout, but use a simpler RC-filtered power supply with a 2-diode full-wave rectifier (the G40V schematic shows the voltages to aim at for each node): Of course, you can just copy the pignose power supply if you want, but it's overly complicated for this simple amp IMO.

To help you design a simple RC-filtered  power supply. Merlin's preamp book and web site show you how to vary the voltages at each node by changing resistor values, and how to ensure adequate filtering using a simple formula to choose capacitor values. If you want to experiment with "sag", simply leave a spot for an extra resistor right after the reservoir cap, in series with the string of RC filters.




The biggest things you can control are screen voltage vs. plate voltage, fixed bias vs. cathode bias and amount of NFB (including the choice of no NFB). Do a little reading on this and other forums on how to implement a switchable fixed bias vs cathode bias (it's easy) and NFB disconnect switch (also super easy).

Now you can read all the old amp books (I bought several tube amp textbooks that go back to as far as 1935), and study the popular guitar amps (also make sure you have the power tube datasheets), and actually try things for yourself. A cheap one-channel scope (from eBay, whether Tek, Kiethley, BK Precision, Tenma, etc) is super handy to see waveforms - just make sure it comes with a high-voltage 1kV probe.

You can read stuff for the rest of your life,but building/reading/tweaking will teach you so much more. Of course I could be all wrong, but that's what worked for me 

[pinkphiloyd]

The biggest things you can control are screen voltage vs. plate voltage, fixed bias vs. cathode bias and amount of NFB (including the choice of no NFB).

I've actually been thinking the last couple of days about putting together some type of prototyping/experimenting board.

I actually feel like I have a solid beginning understanding of the biasing methods and their effects, as well as negative feedback.  It's the screens that have really thrown a wrench in things for me, but I've re-read some material I already had over the last couple of days (as well as a couple of EXCELLENT threads that I found right here on this board) and the whole power amp subject is already starting to make much, much more sense.  I still have a long, long way to go, obviously, but I at least feel like I have my feet under me now.

[vibrolax]

Another reference that is hi-fi oriented, but still interesting in the breadth and depth of its treatment is "Valve Amplifiers" by Morgan Jones
Here is a link to a 631 page pdf someone has made of it:

http://www.pearl-hifi.com/06_Lit_Archive/14_Books_Tech_Papers/Jones_Morgan/Valve%20Amplifiers%203rd%20Ed/Valve_Amplifiers_3rd_Ed.pdf

I have Merlin's Preamp book as well as Kevin O'Connor's TUT3.

Another hi-fi reference I've followed for over 10 years is John Broskie's TubeCad journal: http://tubecad.com/
If anyone is thinking about new topologies for tube and tube/silicon hybrids, it's Broskie.

Jon

[HotBluePlates]

Essentially everything worth doing has already been done. Don't sneer at this wealth of proven plans. If there is anything left to do, it will come out of the features and failings of what has come before.

... If you want to learn how to *design* amplifiers then read, experiment, read, try something else, read some more, build some more. There are MOST DEFINITELY new ideas to be found out there.

Yes, designing is an added layer of understanding what is being built. So you're right, and there are some clever trick which are not commonly done which can be employed.

But PRR is right also. Post any clever plan you feel is a new breakthrough; I bet money one of us can find a published (or patented) design which does the same thing.

> Ic's controlling cathode I in a PA

MusicMan used Silicon driving the cathodes of big bottles.

And there's PRR doing exactly what I suggested. Extra explanation: MusicMan used transistors to receive the preamp drive signal, and they in turn drove the output tubes which were operated in grounded-grid configuration. That is, the grid was tied to the bias supply, and the transistors drove the output tube cathodes. You could even look at that as a transistor output stage with tubes providing high voltage-swing capability to the output stage.

There was a guy who previously visited this forum who built an inverted output stage out of curiosity; that's one where the drive voltage from the preamp is applied to the output tube plates, and the speaker output is taken from the grids of the tubes. Mostly, I think he did it because the mode of operation was described in an old magazine, and he wanted to satisfy his curiosity about how it performed.

The easy ways of using tubes have already been done and the sensible plans are the ones that are the most-copied. The unusual variations are born out of a real or perceived shortfall in the "usual plan" under certain circumstances, and almost universally pay enormous costs in terms of efficiency, cost, and/or weight to obtain marginal improvements of the perceived shortfall.

Eve up to the early-mid 90's, there were tube audio magazines where EE's came up with some wild gain blocks; but they might use 3-4 triodes which as a group delivered a voltage gain of ~20, but the overall gain block was optimized for low distortion and low output impedance, or with no capacitors anywhere in the circuit. Perhaps not useful in a guitar amp but maybe useful in hi-fi audio where the designer was trying to squeeze out the last 1-2% of performance at any cost.

I've found as soon as I think I've come up with a "new idea," after time and research someone already did it and much more 50-60 years ago when tubes were old-hat.

[Ritchie200]

Sorry gotta call B.S. there.

There are MOST DEFINITELY new ideas to be found out there.

I'll tell you what, I'll let you hold YOUR breath until you find those "MOST DEFINITELY new ideas".  I'm sure your experimental budget, equipment, and personal design acumen rivals that of Fender, Marshall, McIntosh, etc, etc.?  Oh and I'm sure your experimental budget, equipment, and documentation (Oh that's right, you don't need 80+ years of rubbish - sorry, my bad) rivals that of the original tube manufacturers like GE, Mullard, Tung-Sol, Telefunken, etc., etc.?  After you make your groundbreaking discoveries, you can post them here.  While you slowly turn a dusky blue, we can then post vintage documentation to "certainly make it true".  Hopefully you will still be in an upright position to read it.

Jim

[DummyLoad]

OK, what i haven't seen: but it probably does exist...maybe in a galaxy far, far away, on alderaan... 

SS high volt-high, high-current op-amps used for cathode drive class AB with both op-amps also used as the phase inverter, driving a grounded grid, fixed bias, UL power amp stage comprised of 6550/KT88. 4 tubes 200W, with SS reliability.

think music man with op-amps instead of discrete/op-amp drive w/ UL instead of of pentode mode.

music man used 2 op-amps as the phase inverter each op-amp drove the discrete cathode driver section of each output phase.

--pete

[jojokeo]

Pete, now you're going to get Jimbo going on his Major & 88's? 

Ed & other's (myself included) are all saying same thing, get that iron out and build to your heart's fancy. Not saying to "copy" at all. But just freaking build whatever you can think of. Maybe build whatever makerDP can think of? I know this, that if anyone tried to build what PRR can think of - he wouldn't be done in 40 or 50 years lol. Anyway, what's the big deal here? Cascading 8 preamp tubes until your guitar tone is completely non-existent? No touch sensitivity, no cleaning up with the guitar Vol knob? The true beauty is finding the zone between doing just enough of what's needed with the idea that keeping things simple is truly best. Best for tone and best for reliability. Best for a lot of reasons. Complicated doesn't make it better for guitar amps. There is a point where two laws come into play. Murphy's law and the law of diminishing returns. By no means am I trying to dissuade anyone from trying to discover how to harness fusion inside a tube amp but how much time and money does a person have to devote to this objective which at the outset is marked by 3/4 of a century of those that have tried before him including some pretty stout players and manufacturers and inventors like Jim mentions?

[Ritchie200]

These aren't the years of designs and spec sheets you are looking for.  Move along.

Jim

[pinkphiloyd]

Jesus, I wasn't trying to start a war.  I just wanted to know how to cook up a decent sounding output section!  Or tweak an existing one.

[Ed_Chambley]

Pete, now you're going to get Jimbo going on his Major & 88's? 

Ed & other's (myself included) are all saying same thing, get that iron out and build to your heart's fancy. Not saying to "copy" at all. But just freaking build whatever you can think of. Maybe build whatever makerDP can think of? I know this, that if anyone tried to build what PRR can think of - he wouldn't be done in 40 or 50 years lol. Anyway, what's the big deal here? Cascading 8 preamp tubes until your guitar tone is completely non-existent? No touch sensitivity, no cleaning up with the guitar Vol knob? The true beauty is finding the zone between doing just enough of what's needed with the idea that keeping things simple is truly best. Best for tone and best for reliability. Best for a lot of reasons. Complicated doesn't make it better for guitar amps. There is a point where two laws come into play. Murphy's law and the law of diminishing returns. By no means am I trying to dissuade anyone from trying to discover how to harness fusion inside a tube amp but how much time and money does a person have to devote to this objective which at the outset is marked by 3/4 of a century of those that have tried before him including some pretty stout players and manufacturers and inventors like Jim mentions?

Plus it is much easier to make a breadboard for building effects.

[Ed_Chambley]

Jesus, I wasn't trying to start a war.  I just wanted to know how to cook up a decent sounding output section!  Or tweak an existing one.

It's all good.  I love to experiment with power sections.  Actually more than preamps.  Right now I am making a Dual Output Transformer power section.  My plan is 4, 6v6 tubes switchable to 2.  Choke input and will be about 20 watts or 10 watts.  I really like the tone of low voltage 6V6.  I also have experimented with lowering the grid voltage and for a blues amp it is really great.

HBP told me this was a good way to get some sag and have less heat in the chassis.  Yes, there are plenty of tweaks and things you can do.  All others are saying is it probably has already been done.

Even if it has been done doesn't mean I cannot do it and even tho it has been done I haven't heard it and most of all some tweaks add a "feel" to an amp which IMO is what inspires me to play.

[pinkphiloyd]

Yes, there are plenty of tweaks and things you can do.  All others are saying is it probably has already been done.

Ha ha, I figured out as soon as I got into this hobby and started trying to tweak my first simple mosfet booster that there was nothing new under the sun.  I just want to learn all I can.

[jojokeo]

Plus it is much easier to make a breadboard for building effects.

Whachu talkin' 'bout Willis?! 
I like your earlier post about marrying your fav amp section(s) together. This is where things get really fun!

pinkphiloyd (nice name BTW) - You just can't buy an amp out there with these attributes unless you can either do it yourself or pay bucks to get somebody to do it that can and will have time for you. But those guys are hard to come by. Unless you frequent forums like this one and make friends with the right people. Many folks on this website can't do that...but are learning.

I don't know your experience level but most have problems even copying a schematic and building an amp without issues in the first place. Just look at all the threads which proves this. Then once you get familiar and past this stage usually amps begin to be built as Ed described and really is where ideas come from for many of the boutique-r's out there. But trying to come up with something that nobody's ever done before? Wow, that's a lot of hubris and/or ignorance to even think possible? No offense intended at all. It's just daunting to think that after all the decades that "you" would be this chosen one? Now you or someone could maybe come up with an idea of putting together some various parts of designs together for a final outcome that hasn't maybe been tried and be successful? But still - the parts or pieces have been done before to make the whole. Does this qualify it to be considered a break-through? In the end does the net result - if successful - make it good for guitar playing or not?

Putting this idea in another perspective - if everyone on this or any other forum tried to put all of the collective "brains" together, and it's been tried, there still isn't a new widget or way that's been discovered in this regard that I'm aware of?

Jesus, I wasn't trying to start a war.  I just wanted to know how to cook up a decent sounding output section!  Or tweak an existing one.

HBP told me...

HBP is a wealth of helpful information with a terrific way to explain the very technical in a layman's sort of way easy to understand. Many posters on this thread bring some heavyweight cred & experience which is wise to take heed... all except that Jimbo guy 

[Ed_Chambley]

Plus it is much easier to make a breadboard for building effects.

Whachu talkin' 'bout Willis?! 

What I am sayin' is transistors missing a leg stubbed in place of a diode can make a pleasant change.  What Willis means is he likes a bunch of different tones, even a lot that do not come from tubes as blasphemous as that may be.

OOPS, I forgot I don't mess with no pedals unless I do not like the way the sound.

[pinkphiloyd]

But trying to come up with something that nobody's ever done before? Wow, that's a lot of hubris and/or ignorance to even think possible?

I never, ever, suggested anything even remotely close to this.  Quite the opposite, in fact.

[jojokeo]

My bad pink - again no offense intended, somewhere along the line the thread's direction seemed to turn in this direction and jumped the shark maybe?

[MakerDP]

But trying to come up with something that nobody's ever done before? Wow, that's a lot of hubris and/or ignorance to even think possible?

I never, ever, suggested anything even remotely close to this.  Quite the opposite, in fact.

If you need help debugging an amp circuit or understanding how something works you can get some great information here. There is a ton of knowledge here.

However, this forum is most definitely NOT the place to go for innovators. Most people here are stuck in the past... Arrogance abounds as you can see. This is a place for copy-cats... not that there's anything wrong with that. We all gotta start someplace and most people are perfectly content to stay there which is ok.
There is absolutely NOTHING wrong with starting with a good foundation and building on what others have done before but if you want advice from people who won't try to shit on your dreams of becoming the next great amp designer do yourself a favor and go somewhere else.

[jojokeo]

But trying to come up with something that nobody's ever done before? Wow, that's a lot of hubris and/or ignorance to even think possible?

I never, ever, suggested anything even remotely close to this.  Quite the opposite, in fact.

If you need help debugging an amp circuit or understanding how something works you can get some great information here. There is a ton of knowledge here.

However, this forum is most definitely NOT the place to go for innovators. Most people here are stuck in the past... Arrogance abounds as you can see. This is a place for copy-cats... not that there's anything wrong with that. We all gotta start someplace and most people are perfectly content to stay there which is ok.
There is absolutely NOTHING wrong with starting with a good foundation and building on what others have done before but if you want advice from people who won't try to shit on your dreams of becoming the next great amp designer do yourself a favor and go somewhere else.

Now I know why and where this "shark" came from!

[pinkphiloyd]

My bad pink - again no offense intended, somewhere along the line the thread's direction seemed to turn in this direction and jumped the shark maybe?

I frequent many, many forums.  It happens.  No worries.

[pinkphiloyd]

I've been doing some googling this morning without much success.

I read somewhere awhile back, at least I think I did, that the difference in response of EL84's regarding fixed vs. cathode biasing was negligible compared to other tube types.  Anybody care to explain why this is or point to a link?  I'm not finding much at the moment. 

[John]

But trying to come up with something that nobody's ever done before? Wow, that's a lot of hubris and/or ignorance to even think possible?

I never, ever, suggested anything even remotely close to this.  Quite the opposite, in fact.

If you need help debugging an amp circuit or understanding how something works you can get some great information here. There is a ton of knowledge here.

However, this forum is most definitely NOT the place to go for innovators. Most people here are stuck in the past... Arrogance abounds as you can see. This is a place for copy-cats... not that there's anything wrong with that. We all gotta start someplace and most people are perfectly content to stay there which is ok.
There is absolutely NOTHING wrong with starting with a good foundation and building on what others have done before but if you want advice from people who won't try to shit on your dreams of becoming the next great amp designer do yourself a favor and go somewhere else.

I disagree. There's been quite a few innovators here that have come up with exceptional circuits and amps. Tubenit in particular designs an amp to get *his* sound, not someone else's.


To design a new killer amp circuit, I'd think first you have to design a new killer tube that behaves differently than all the rest. Or better yet, a new killer transistor that finally emulates a tube exactly.

[kagliostro]

Do you mean something like this stuff ?

http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=1019936&url=http%3A%2F%2Fieeexplore.ieee.org%2Fiel5%2F16%2F21940%2F01019936.pdf%3Farnumber%3D1019936

K

[Ken Moon]

Another great source of amp info is the collection of articles written by Norman Crowhurst in the late ''50s and early '60s. Many are available online.

He had a very readable writing style, with practical info added, much like Merlin.

[VMS]

 but if you want advice from people who won't try to shit on your dreams of becoming the next great amp designer do yourself a favor and go somewhere else.

Sorry gotta call B.S. here.   

[kagliostro]

I repeat

consider to read the book of Richard Kuehnel

it worth the effort

Franco

[shooter]

Nice find Franco, I love nano tubes!  nixie tubes are cool also

[Ritchie200]

However, this forum is most definitely NOT the place to go for innovators. Most people here are stuck in the past... Arrogance abounds as you can see. This is a place for copy-cats... not that there's anything wrong with that. We all gotta start someplace and most people are perfectly content to stay there which is ok.
There is absolutely NOTHING wrong with starting with a good foundation and building on what others have done before but if you want advice from people who won't try to shit on your dreams of becoming the next great amp designer do yourself a favor and go somewhere else.

There is something abounding here for sure....  Nobody is pissing in your cornflakes of dreams except for you.

If you have spent any time and research on this site you would know that there are hundreds of new designs and schematics that the original designers have freely posted.  Many of those designs were collaborative efforts with fantastic input and past experiences shared.  Most of those have been from the dinosaur members you like to pass off as irrelevant.

If you have spent any time and research on this site you would know that there are many people who throw "new" ideas out and ask if they would work.  Again, those dinos will patiently explain how that design will melt the insides of the tube or be very non-musical and then show why - using all that old theory and those useless spec sheets and graphs.  Most people use it as a learning experience to help them on their next design.  We discuss and agree and disagree.  Up until now, I've never seen anyone asking those questions feel like their manhood has been threatened. 

If you have spent any time and research on this site you would know that the dinos come here and spend countless hours helping folks understand the theory, designs, and most important - all the little things they don't talk about in the books when you tweak this and that. Those dinos will forget more than most of us will learn.  The only thing abounding here is your sarcastic immature attitude.

We are working with components that have a very specific performance curve that is well documented along every combination of influences.  Over 80 years of manufacturing and design expertise has gone into that documentation.  However, since we don't have a clue around here, can I suggest some homework for you?  Do some research and give me a list of the "greatest amp designers" you know and would like to grow up to be some day.  Then give me a list of their "groundbreaking designs".  I will then show you the tried and true designs of yesteryear that they copied and tweaked and I don't know a fraction of what the Dino's know.  Not bad for a self confessed rookie.  Maybe the copycats on your list will grow up someday and become the innovator that you are.  Wish in one hand and crap in the other, see which one gets filled first.  With your charm I'm sure people will be waiting in line to help you achieve your dream. 

Have a nice day!   Back to our regularly scheduled program.
Jim

[PRR]

I just pissed-off someone on another forum, bad. This isn't my month. Sorry.

> ...NOT the place to go for innovators. Most people here are stuck in the past... Arrogance abounds

Pretty arrogant words.

I've followed all the fads since Tubes Ruled (before transistors became practical). Followed the idea-wars in RE&P, Audio, Wireless World, even tame PE. Experimentally anticipated some plans which became commercial (the MusicMan cathode-drive, the floating driver now used in many high-power transistor amps). If you go this way, it can be a lifetime of mental stimulation. I don't think it made the music better. That's usually about taking a simple plan (of whatEVER topology and technology) and refining it.

I can't think of any audience which applauded a clever amplifier detail.

Looking back, maybe I'd like to steer others away from the self-stimulation path and toward the productive path of Making Music. I sure am not the one to object to self-stimulation! But for folks with more talent than me, it is not the best use of their precious time.

In guitar-amps:

You need pentode power (triodes and UL are too polite to rock).

Align-grid tubes (6L6 6V6 6550 KT88) are different than slop-screen tubes (EL34 EL84) but the two types have been used interchangeably and in the right hands both do fine sound.

Speaker is often more important than amplifier. (So why aren't we discussing curvilinear versus ripple cones or voice-coil dimensions?)

NFB is a KEY tweak.

With these thoughts, you can rock-out an old Philco console radio or a Bogen factory announce amp, 6 or 8 snips.