Engineering help on Amplifier Design

[LukeCurd]

I am NOT an Electrical Engineer but I have a elementary understanding of electronics.
The amplifier I want to play is not being made by anyone.

I have my head spinning reading every article I can find on amp circuits. In the end I have found I need some help.

Anyone wish to go down the rabbit hole with me?

 

[steve_k]

Vapor Ware?

 

[LukeCurd]

More like a non master volume high gain plexi head with switchable tone stacks.

 

[maddnotez]

Why no master? Just curious. One channel?

 

[jerrydyer]

More like a non master volume high gain plexi head with switchable tone stacks.

peice of cake. are you going to build it or commision someone to do so?
thanks

 

[LukeCurd]

More like a non master volume high gain plexi head with switchable tone stacks.

peice of cake. are you going to build it or commision someone to do so?
thanks

I a willing to commision anyone for working design. I have contacted to Bogner,Friedman, Suhr, Diezel, Peters, Splawn, Germino, 3 monkeys and metro amps. They all told me that a 1 off build to my specs would cost more trouble than its worth. These amp builders are too busy selling their own designs to even mod amps anymore.

My basic premise is make something unique that works for my playing style.

I have narrowed down what I want to achieve but not sure how to best design it.

I love the sound of a parallel 1st gain stage, plexi style where I can dial in how dark or bright the amp is. On a standard bassman/plexistyle tone stack I run the dark gain around 6 and the bright gain on 4.5. Bass 4 Mids 6 Treble 5 presence 4.

I want to run it non master volume with 4 gain stages and a switchable mid eq tone stack shift like the old ampeg's if possible.

v1a bright
v1b dark
v2a gain stage
v2b gain stage
v3a gain stage
v3b cathode follower
v4 phase inverter

I also want to run higher plate voltages, Odd filtering and such. I don't want a clean channel, effects loop or any switching.

Come to think of it I don't even need the switchable tone stack. Depends on how it would complicate the design for my grasp. The old ampeg's run a 6k11 tube for the active tone stack which has three parts split into 3 mid frequency centers. I found the 350hz and 1000hz centers made good shifts. Above that this mids sounded very thin but you could do cool stuff like shift the mids in the mix. Cool Idea but would rather mod a old ampeg for that type of sound.

So the MAIN reason I want it to be non master volume is I think it will sound better for me. I love those style amps, Old Univox,Musicman,Hiwatt,Ampeg, the list goes on for old power house amps that will split your wig. Some of that mojo was running the amp wide open. For me that's the Sound!

 

[maddnotez]

Sounds like a great idea..

 

[jerrydyer]

you want two seperate inputs both running paralel gain stages so you can blend both. sort of like a dual non master plexi. I think it would be cool to do that and than also seperate tone stacks. you could then just a/b the front. not sure why you want the additional gain though without a control wedged in there somewhere. you can have that without installing a MV. or you do one input paralele and then have another gain stage on tap, and footswitchable, with its own volume. but then it becomes nec to use a MV to equlize the final volumes of both channels.

 

[LukeCurd]

I will also up the stakes and say I wan't to run fixed resisters in the tone stack rather than potentiometers. If I keep my settings the same why not? Might sound cool. Just not sure how to do it.

Imagine a amp, GTR In, Spkr out, AC power in. That's it. Just plug in and play the damn thing!

 

[mrTapp]

More like a non master volume high gain plexi head with switchable tone stacks.

peice of cake. are you going to build it or commision someone to do so?
thanks

I a willing to commision anyone for working design. I have contacted to Bogner,Friedman, Suhr, Diezel, Peters, Splawn, Germino, 3 monkeys and metro amps. They all told me that a 1 off build to my specs would cost more trouble than its worth. These amp builders are too busy selling their own designs to even mod amps anymore.

My basic premise is make something unique that works for my playing style.

I have narrowed down what I want to achieve but not sure how to best design it.

I love the sound of a parallel 1st gain stage, plexi style where I can dial in how dark or bright the amp is. On a standard bassman/plexistyle tone stack I run the dark gain around 6 and the bright gain on 4.5. Bass 4 Mids 6 Treble 5 presence 4.

I want to run it non master volume with 4 gain stages and a switchable mid eq tone stack shift like the old ampeg's if possible.

v1a bright
v1b dark
v2a gain stage
v2b gain stage
v3a gain stage
v3b cathode follower
v4 phase inverter

I also want to run higher plate voltages, Odd filtering and such. I don't want a clean channel, effects loop or any switching.

Come to think of it I don't even need the switchable tone stack. Depends on how it would complicate the design for my grasp. The old ampeg's run a 6k11 tube for the active tone stack which has three parts split into 3 mid frequency centers. I found the 350hz and 1000hz centers made good shifts. Above that this mids sounded very thin but you could do cool stuff like shift the mids in the mix. Cool Idea but would rather mod a old ampeg for that type of sound.

So the MAIN reason I want it to be non master volume is I think it will sound better for me. I love those style amps, Old Univox,Musicman,Hiwatt,Ampeg, the list goes on for old power house amps that will split your wig. Some of that mojo was running the amp wide open. For me that's the Sound!

Cool!!

Sounds almost like my next build i´m planning.

I will have selectable Bright/Dark/Parallell input stage...2 tone stacks.
But mine will have master and effect loop, and a preshape control.

/Hasse

 

[LukeCurd]

you want two seperate inputs both running paralel gain stages so you can blend both. sort of like a dual non master plexi. I think it would be cool to do that and than also seperate tone stacks. you could then just a/b the front. not sure why you want the additional gain though without a control wedged in there somewhere. you can have that without installing a MV. or you do one input paralele and then have another gain stage on tap, and footswitchable, with its own volume. but then it becomes nec to use a MV to equlize the final volumes of both channels.

Since my channel masters, gains, and master volume are all at 4-6 depending It just makes sense to have one knob to do all the work.

For instance when I plug into a high gain amp I run the pre on 4 and the master on 4. Gain is tight and articulate. I want more gain I turn the amp to 6. I get more poweramp and preamp gain at the same time. I don't have to adjust 2 knobs at the same time.

I also want a amp that is loud! My ampeg V4 6ca7's was loud, The Metro JTM-45 100 with kt-66 was loud, The best marshall I have ever heard was LOUD! MY OD-100,Uberschall, etc would all get the room pumping.

Played a splawn quickrod and bogner xtc the other day. They both suffered from the same problems, flip off the half power switch, flip off the bright, turn depth off, turn solo off, bypass effects loop, Run channel masters on full, loop on full, master volume at noon along with gain. Lots of damn work just to play a amp.

Then I roll up the guitar volume to start playing, Dial in the presence to taste and all of a sudden the amp comes alive.

I just want something simple to operate!

 

[LukeCurd]

More like a non master volume high gain plexi head with switchable tone stacks.

peice of cake. are you going to build it or commision someone to do so?
thanks

I a willing to commision anyone for working design. I have contacted to Bogner,Friedman, Suhr, Diezel, Peters, Splawn, Germino, 3 monkeys and metro amps. They all told me that a 1 off build to my specs would cost more trouble than its worth. These amp builders are too busy selling their own designs to even mod amps anymore.

My basic premise is make something unique that works for my playing style.

I have narrowed down what I want to achieve but not sure how to best design it.

I love the sound of a parallel 1st gain stage, plexi style where I can dial in how dark or bright the amp is. On a standard bassman/plexistyle tone stack I run the dark gain around 6 and the bright gain on 4.5. Bass 4 Mids 6 Treble 5 presence 4.

I want to run it non master volume with 4 gain stages and a switchable mid eq tone stack shift like the old ampeg's if possible.

v1a bright
v1b dark
v2a gain stage
v2b gain stage
v3a gain stage
v3b cathode follower
v4 phase inverter

I also want to run higher plate voltages, Odd filtering and such. I don't want a clean channel, effects loop or any switching.

Come to think of it I don't even need the switchable tone stack. Depends on how it would complicate the design for my grasp. The old ampeg's run a 6k11 tube for the active tone stack which has three parts split into 3 mid frequency centers. I found the 350hz and 1000hz centers made good shifts. Above that this mids sounded very thin but you could do cool stuff like shift the mids in the mix. Cool Idea but would rather mod a old ampeg for that type of sound.

So the MAIN reason I want it to be non master volume is I think it will sound better for me. I love those style amps, Old Univox,Musicman,Hiwatt,Ampeg, the list goes on for old power house amps that will split your wig. Some of that mojo was running the amp wide open. For me that's the Sound!

Cool!!

Sounds almost like my next build i´m planning.

I will have selectable Bright/Dark/Parallell input stage...2 tone stacks.
But mine will have master and effect loop, and a preshape control.

/Hasse

Right on, How far along in the planing stages are you? Are you going Pre or post phase inverter master volume? I heard post robs tone and compresses the signal.

 

[mrTapp]

Right on, How far along in the planing stages are you? Are you going Pre or post phase inverter master volume? I heard post robs tone and compresses the signal.

Planning ready, but I have another new amp design to be finished first....
This Plexi is number 2 in my que.

It will have pre master!

/Hasse

 

[lespaul3013]

I will also up the stakes and say I wan't to run fixed resisters in the tone stack rather than potentiometers. If I keep my settings the same why not? Might sound cool. Just not sure how to do it.

Imagine a amp, GTR In, Spkr out, AC power in. That's it. Just plug in and play the damn thing!

I wouldn't ever do that personally...changing guits, speakers, cabs, etc. will almost always warrant a little bit of knob twisting for me - plus, different rooms call for different settings...you catch my drift. I would think twice about that.

Maybe instead of B, M, T...put a single tone knob on there? (I know nothing technical about amps so I don't even know if that's possible...just thinking out loud )

 

[LukeCurd]

bizup

 

[JamesPeters]

I a willing to commision anyone for working design. I have contacted to Bogner,Friedman, Suhr, Diezel, Peters, Splawn, Germino, 3 monkeys and metro amps. They all told me that a 1 off build to my specs would cost more trouble than its worth. These amp builders are too busy selling their own designs to even mod amps anymore.

Hi Luke,

Our conversations involved a few custom ideas, none of which were what you're mentioning on this thread. The amp-related ones (not counting your cabinet idea) were of two different camps: one was for your guitarist friend, and involved several possible things (including my giving suggestions for rigs in general whether I made them or not, from AxeFx to plugins to mods to a JCM800 by another tech); the other idea was for a single channel amp (one of my own designs) for you, but with everything stripped--including basic cosmetics--so that it could be made for lower prices than my standard models (which I declined, because I won't do custom work for less than my standard models' prices).

I try to be open minded when it comes to custom amp design requests, spending a lot of my "free time" talking on the phone with people about them, usually to discover that most of these people aren't willing to pay my standard prices let alone anything higher. I keep an open mind regardless because I want to give everyone the benefit of the doubt.

I hope you don't mind my clearing this up.

As for the idea of switchable tone stacks which are "pre-set", I'd have to warn that it's going to be very specific to your rig in particular, and to the room you're using it in. It might prove to be frustrating if anything about your rig changes--including the strings you use--and involve multiple modifications over time to compensate. I could recommend something which would involve lower cost, something easier to have accomplished by most techs, and involve more flexibility: getting a good effects loop installed, then using EQs in the loop to your liking. You can use whatever EQ device you prefer, including some which would involve switching presets if you want. It would involve having EQ effects external to the amp when you want its basic EQ changed on the fly, but what's an EQ pedal or two.

 

[LukeCurd]

I a willing to commision anyone for working design. I have contacted to Bogner,Friedman, Suhr, Diezel, Peters, Splawn, Germino, 3 monkeys and metro amps. They all told me that a 1 off build to my specs would cost more trouble than its worth. These amp builders are too busy selling their own designs to even mod amps anymore.

Hi Luke,

Our conversations involved a few custom ideas, none of which were what you're mentioning on this thread. The amp-related ones (not counting your cabinet idea) were of two different camps: one was for your guitarist friend, and involved several possible things (including my giving suggestions for rigs in general whether I made them or not, from AxeFx to plugins to mods to a JCM800 by another tech); the other idea was for a single channel amp (one of my own designs) for you, but with everything stripped--including basic cosmetics--so that it could be made for lower prices than my standard models (which I declined, because I won't do custom work for less than my standard models' prices).

I try to be open minded when it comes to custom amp design requests, spending a lot of my "free time" talking on the phone with people about them, usually to discover that most of these people aren't willing to pay my standard prices let alone anything higher. I keep an open mind regardless because I want to give everyone the benefit of the doubt.

I hope you don't mind my clearing this up.

As for the idea of switchable tone stacks which are "pre-set", I'd have to warn that it's going to be very specific to your rig in particular, and to the room you're using it in. It might prove to be frustrating if anything about your rig changes--including the strings you use--and involve multiple modifications over time to compensate. I could recommend something which would involve lower cost, something easier to have accomplished by most techs, and involve more flexibility: getting a good effects loop installed, then using EQs in the loop to your liking. You can use whatever EQ device you prefer, including some which would involve switching presets if you want. It would involve having EQ effects external to the amp when you want its basic EQ changed on the fly, but what's an EQ pedal or two.

Well after talking to my buddy bryan more about his rig and pulling out the chassis I got to thinking the 2204 style amps are perfect for his style of playing. He likes them a little hotter than stock but nothing more than a good pedal will do.

In my research for him, I have read and researched more about circuits then when I last spoke with you. Once I discovered how many variables are involved I got even more excited with possibilities. That kinda took me off the amp market a little bit.

After doing more reading I found out how LITTLE I know. I am qualified to repair amplifiers but not design one from scratch.

So I got back on the amp market, demoed some more amps and have found all the amps I like the sound of have:
Low Impedence Plexi Style Output Transformer 1-3k vs Fender style is more around 5-8k?
Heybor transformers tend to sound beefy to my ears.
How much Negative Feedback & Filtering in the power stage effects how the Feel and Sound of the Power Section.
Tend to run plate voltage in the 480-540 range.
And run very different preamps.

I don't see thats different than me saying I enjoy driving a Rear Wheel Drive, V8, Manual Transmission Car is it?

I enjoyed our conversations on the phone as I thought you did. We discussed various topics as you said. I hope you don't feel like you wasted your time. If I made 100k a year and could afford one of your amps I would buy 3 no questions asked. I have all the faith in the world you build a quality amplifier. I didn't mean to lump you in with the other guys I mentioned. I was just trying to expand on my point that I have talked to a bunch of amp builders about various design ideas.

My tastes change from month to month. Some days I don't want to play high gain at all and I think Rock is just cheesy and I listen to some coltrain and get blown away.

It depends, Its a ongoing tone chase with me.

No hard feelings,

Luke

 

[MississippiMetal]

My tastes change from month to month.

Which is exactly why I wouldn't be breaking my neck to help you design anything, and likely why the other builders aren't either. Nobody wants to build or help you build something that you may hate a month after you get it just because you can't decide what you want.

 

[glip22]

Why did I just read this thread

 

[JamesPeters]

Luke,

I also enjoyed our phone calls. I however wanted to clear up what you said in that post, so people don't get the wrong idea about me. As I'd mentioned to you even in our first phone conversation, it's not so much about getting a sale as it is about helping you get what you really want (since I'll get sales anyway, and I'd rather not sell an amp to someone who doesn't really want it). I thought your friend's amp was a good fit for him already, so you'll recall how in the end I was trying to steer you toward getting it re-capped (and possibly having a new loop added) by a local tech. So I have no hard feelings about that.

About what you've learned you like in an amp--those things, out of context, don't say much. For instance, if a Fender amp uses an OT with a higher impedance: if the amp uses 6L6, a higher impedance is a better match than the lower impedance a Marshall OT (with EL34) would have; it's about keeping it an apples-to-apples comparison, since those two tube types generally work in their "normal ranges" (with a relatively similar power amp design) if the output impedance is appropriate. Also if you've found the amps you like use a B+ of a certain range, perhaps it's due to other things and not so much the B+ level. Maybe you just like old Marshall amps. Don't get distracted by technical details, when you know what amps you like anyway.