SOT: Attempt at "tubish" MOSFET amp

[Steben]

And so, the complexity grows and grows, until we have yet another solid state amp to ruin our tube-world. Lol, just kidding. I really like the idea though.

Any sample sound clips anytime soon?

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Jimbo

Well, even when just kidding, I kinda DO LIKE searching for non-tube electronics. Because let's be realistic: We don't need to search any more for tube electronics: we know everything.

Maybe one day one can say: wow! what a nice holy grail
sound! realizing that there's no tube sound at all.
The Fuzz face is the most known distortion device in the world: just try making a fuzz face sound with only tubes! Good luck I would say.
No univibes, no fuzz faces, no treble boosters, ...
That would be quite a step back.

[puretube]

:?:  :shock:  :!: ...

[petemoore]

When asked 'Tubes Or Transistors" I reply "I Gotta Have BOTH !"

[JimRayden]

And so, the complexity grows and grows, until we have yet another solid state amp to ruin our tube-world. Lol, just kidding. I really like the idea though.

Any sample sound clips anytime soon?

------------
Jimbo

Well, even when just kidding, I kinda DO LIKE searching for non-tube electronics. Because let's be realistic: We don't need to search any more for tube electronics: we know everything.

Maybe one day one can say: wow! what a nice holy grail
sound! realizing that there's no tube sound at all.
The Fuzz face is the most known distortion device in the world: just try making a fuzz face sound with only tubes! Good luck I would say.
No univibes, no fuzz faces, no treble boosters, ...
That would be quite a step back.

Yea, transistors totally rock the stompbox world. And actually the best digital devices out there have the exact copies of tube sounds. It's just... it's not the sound. To me, I like to know that my guitar signal goes through those big hot glass bottles and sound really really good. I don't have anything against transistor amps, maybe I'm just a lil' old-fashioned (although I was born well after the invention of transistor ). While I'm not too fond of transistor amps, there is one thing I can't stand - digital modelling amps. (You might think this is totally senseless but this is me.)
Well, you can give me a digital amp and tell me it's a tube amp and as long as I can't hear any difference, I'll be happy with it.
It's a psychological stuff. I love tubes. Tubes love me.

But yea, I think I'm going to build your amp once it's ready, and make an A/B test with my tube amp. Maybe I'll change my way of thinking.

Oh, and if it's possible, and if you haven't thought of that yet, maybe you could add an OT to it. Or at least an OT simulator.

----------
Jimbo

[brett]

Hi.

I love tubes.  Tubes love me.  

Me too.  That's why I'm aiming for a GOOD, tube-like, cheap solid state amp.  FETs and MOSFETs are the closest things we have in solid state to valves.  In fact, their operation is quite analogous to valves, so I don't see why we can't get some reasonably valve-sounding amps if we use them.  (Though someone hear might explain that I'm misguided).  

The other advantages are that it is low-cost and low-voltage.  I costed the parts for my MOSFET design last night, and I think this would cost no more than $80 (AUD, =$US50) as a head, including the cost of a plugpack ($20) and cheap case ($15).  Anyway, it's Friday, and a long weekend (Labour day), so I'll do my best to put this thing together, see how it sounds and get back to you all.

thanks for the comments.

[Steben]

And so, the complexity grows and grows, until we have yet another solid state amp to ruin our tube-world. Lol, just kidding. I really like the idea though.

Any sample sound clips anytime soon?

------------
Jimbo

Well, even when just kidding, I kinda DO LIKE searching for non-tube electronics. Because let's be realistic: We don't need to search any more for tube electronics: we know everything.

Maybe one day one can say: wow! what a nice holy grail
sound! realizing that there's no tube sound at all.
The Fuzz face is the most known distortion device in the world: just try making a fuzz face sound with only tubes! Good luck I would say.
No univibes, no fuzz faces, no treble boosters, ...
That would be quite a step back.

Yea, transistors totally rock the stompbox world. And actually the best digital devices out there have the exact copies of tube sounds. It's just... it's not the sound. To me, I like to know that my guitar signal goes through those big hot glass bottles and sound really really good. I don't have anything against transistor amps, maybe I'm just a lil' old-fashioned (although I was born well after the invention of transistor ). While I'm not too fond of transistor amps, there is one thing I can't stand - digital modelling amps. (You might think this is totally senseless but this is me.)
Well, you can give me a digital amp and tell me it's a tube amp and as long as I can't hear any difference, I'll be happy with it.
It's a psychological stuff. I love tubes. Tubes love me.

But yea, I think I'm going to build your amp once it's ready, and make an A/B test with my tube amp. Maybe I'll change my way of thinking.

Oh, and if it's possible, and if you haven't thought of that yet, maybe you could add an OT to it. Or at least an OT simulator.

----------
Jimbo

Jim, I'm not questioning Tube amps (at certainly not power amps)!  :wink: I was simply argueing that solid state design is the one to be thinked through and redesigned in order to achieve even newer tones, not just tube emulating.
Tube amps are what they are since half a rock century: the best in simple tone. By the way: this IS stompbox world and although it's funny to see some experiments: Tubes do not belong in small metal cases.

[puretube]

I`m allowed to break rules, and love to bring stompboxes back to their sound roots  

[JimRayden]

I never said anything wrong with solid-stateness either. As soon as you get the amp ready and tested, I'll build it. If it sounds good, I'm gonna stick it into a cab and buy a celestion for it. And start using it for home practice. And then apologize to the gods of solid-stateness, for I have had the wrong impression of them.

Oh, and Steben, I think exactly the same. Transistors are good for making new tones, etc. But most of it can be done with tubes also. For example take a look at puretube's work, wich I admire.

-----------
Jimbo

[puretube]

thanx for the flattery, Jimbo  

upon popular demand I`ve re-opened my sites...

[JimRayden]

I just found this ol' thread again. I've been thinking about this project. Are there any threads of this one completed? I'd sure like to hear that.


---------
Jimbo

[squidsquad]

I've been intrigued by this schem for a couple years....wishing someone might try a build & give a review.  It sure looks cool to me...might be a bit beyond my skills...but not TOO far.

http://www.redcircuits.com/Page52.htm

[brett]

Hi.
The schematic above is for a fairly conventional small amp.  Circuits such as this have been largely replaced by single-chip devices.  Although they're no without their problems (such as thermal shutdown mid-riff), they are probably the way to go for smallish SS amps (5 to 10W) where tone isn't a big factor.
I'm still looking at using a MOSFET as a voltage follower in a small class A amp.  Progress is slow because there's too many other things on...
cheers

[Steben]

I guess a non-FET design won't do the job. If you get distortion from the preamplifier (in this case the two JFETs) why not use a IC-pcwer amp indeed.

I really think the design of a MOSFET-including power amp is still usefull.

[Nasse]

http://www.elektor-electronics.co.uk/Default.aspx?tabid=28&art=50483

Did anybody try this one???

The schem looks like high power Jack Orman minibooster

[Ge_Whiz]

The Elektor design is well up my 'to-do' list, but will take a little design time since I discovered that it would cost me £25 to get the PCB from Elektor (including postage). NO WAY!  :evil:

[Threefish]

Hey Squidsquad,
I was looking into that design as well, and emailed the designer about it. He put me on to an Australian company who are marketing it. For what it's worth, go to their site :
[url]http://www.ledeaudio.com/audio_kits.html
and scroll down until you see "10w guitar amp". They don't seem to have any sound samples though, or any more info than the designer's site.

[octafish]

Just thought I'd give this a bump and ask brett if there was any progress?

[mac]

Cant see the schematic "404 Not Found"... Anyway...

If I had to build a mosfet/fet amp I will follow http://runoffgroove.com ideas ( eighteen, professor tweed ).
I'll bet to a 2 or 3 mosfet/fet preamp and then the power amp in A or AB config, just like any tube amp.
See http://www.18watt.com . I'll just adapt this simply design to be used with mosfets/fets.
No ICs or silicons transistors.

But I'll use high voltage, 100V at least... And I'll buy a good death insurance... just in case
Why? Imagine a photo of the signal into a tube at 110V. Then resize it down to 9 - 30V, as in any IC or transistor. You'll loose the fine details.

mac

http://www.geocities.com/guitarfxs

[Jaicen_solo]

I think you're on the right lines there.
What I want to see is a super simple mosfet power amp mated to one of those runoffgroove 'emulators' or better still a Plexi front end.
Or even have a multi channel input stage, with a doctor tweed and a Plexi. That would be brilliant if you ask me. 1/2 watt would be just fine through a 1x12. Also, i'd like it to run off 18-24v so as not to kill me for being careless.
Got that? Ok, go make me one

[JimRayden]

But I'll use high voltage, 100V at least... And I'll buy a good death insurance... just in case
Why? Imagine a photo of the signal into a tube at 110V. Then resize it down to 9 - 30V, as in any IC or transistor. You'll loose the fine details.

mac

http://www.geocities.com/guitarfxs

That doesn't make any electronical sense to me. You have no idea how tiny the fine details can go if they do exist in your signal. If you have an analogue signal, you'll have to take it down to electron sizes -in both voltage and frequency- if you want actual blur in your sound. Well that's my vew at least. It's the actual clipping process that we're after, the preservation of it is simple.

Though correct me if I'm wrong.

---------------
Jimbo