Guitar Amp

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The ultimate amp depends very much on what you want the amp for, and within catagories it certainly is still a matter of taste.

I myself am not very familiar with solid state kit amps available, I suspect there are some fine ones. Tube amp kits abound, and probably the most popular one is to clone the Fender Deluxe or "5E3."

Kits are good for the novice because they come with everything you need. Or at least they do if you buy a complete kit. You won't get it half built and realize you never ordered some part. Many of them come with premade chassis ready for your build on the interior. Transformers already selected, etc etc.

Of course you can build from scratch, find or make your own chassis, buy transformers and other parts from suppliers of your choice. But you want easy to build, so I'd steer you towards a kit. Explore kits, as some come with more detailed instructions than others. Kits come in everything from just the electronic parts, complete chassis kits, or complete amplifiers with cabinet and speaker. Kits come in the very basic like the Fender Champ, up to fairly complex, like Twin Reverb.

Kits are not really a way to save money, they are not cheap parts discounters. A kit can cost you about as much as an amp ready made, but you get the satisfaction of building it and learning something. Some kits cost more than others, and some of that difference is in the parts. Off the top of my head, some kit purveyors are TedWeber, Mission amps, Mojo, and many others.

There are web sites devoted to building guitar amps, the AX84 site is popular and covers a number of proven designs, and hosting forums full of people who have built them or are building them.
 
Hey!

What is the ultimate diy guitar amp now? The amp should have a clean/warm sound and be easy to build. It can be tube or solid-state...

Ty for your response and help.

Well, it just seems to me the "ultimate" guitar amp project would be a D inspired Over Drive Special ; based loosely on the Fender Twin... Not sure how easy to build as a "DIY", but I'm thinking of doing one of these as my next project...

I would build a Fender Twin, and that is supposed to get you like 90% there....

-g
 
Hi axl666, I thought from your name you may be going toward the deathmetal side..
But if you're looking from clean to warm sound, and easier tube build would probably be a Class A type low watts, I would look at early Fender Champ types or similar. Plenty of kits and parts available to support it. Don't know if you have experience with high voltage stuff so be sure you know what you are doing with tube amps circuits first..

My ultimate build (I hope one day) will be something like Trainwreck Nancy, she is all nice manners til you crank her up, and then she is downright dirty.

The ultimate build is one that works, and also ends up sounding the way you want, after much much fiddling around with it.
 
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I made this schematic, please check it. I work with electronic every day, but never designed an amp. So i am quite new on audio electronics.

I have an GT-10 multi effect so i need a good clean amp. I wil use NE5534, OPA132, AD823 or AD744 for the preamp. Any suggestions for the power amp?


Sorry for the late reply.
 
(OK. Typing too much makes the session expire, and the text to be lost when clicking "Preview". Lesson learned 'till I forget again.)

First, I recommend you a good read on audio amplifying. Begin with small signal (preamps), and leave power for later. You really can get a working amp, but it can sound horrible, wasting your efforts. Besides that, you have to know what you're doing before dealing with power stuff, because devices and fingers burn.

Now on the circuit:
The first two opamps will latch at one of the power rails as long as the amp is on. Unless you reversed their inputs :rolleyes:.
What are you trying to do with the first three opamps? They seem overkill for this section (buffer and gain control).
The connection between the two first two opamps inputs doesn't look sane, specially for lower frequencies.
The equalizer will probably have quite less effect than intended, specially when cutting frequencies, due to the summing at the end.
Do you really need so many eq bands? What do you expect to have below, say, 60Hz? Did you calculate the overlap between bands?
The excess devices and some resistor values point to noise and low input Z (not for the GT-10, but for when you bypass it for dry signal, which is useful sometimes).
Besides, your drawing doesn't tell whether crossing lines are connected or not. We can guess, but we really shouldn't.

After you understand all those preamp points, study about guitar signal processing, which is a whole different beast - specially when it comes to tone and linearity. Remember to read about "tone stack" at some point (don't begin by it).

Best regards,
Emerson
 
Agree with Emerson that there is a lot (too many) opamp stages for what is needed. If you already plan on using the multi-effects at front end, then I expect most of the sound shaping you would want done by that. You said clean, so you need just a simple buffered preamp in, maybe with adjustable gain, a tone stack or eq stage and then out to your power amp (maybe through another op amp stage, depend on tone stack's output). The power amp could be a simple push-pull type with transistors. I have no idea what your rail voltage is from the drawing, and that is a big factor in determining the headroom and how clean it stays before clipping point.

I would back up a bit here, because this started out about what would be the best/ultimate DIY guitar amp that should also be easy to build. Now we are talking about design of it? That is a totally different thing. IMO if you are designing something to sound good but relatively easy build for a new DIYer, then I think that the above circuit would fall short on that criteria. 2 op amp stages running on single rail 18 V or so would easily provide a very decent pre-amp with a passive tonestack between.
 
Hi Axl666, Sorry if I came across as critical to your design along with my advice. The guitar preamp needs to do only a couple of basic things. In general terms 1st stage should be a buffer of some sort, if you go with op amp (OP1)for that it would need to be setup as unity gain follower or could also do it with a jfet or mosfet .That takes care of the high impedance source from a guitar (if you plug directly in).
2nd stage should provide gain, and with op amp set up as a non inverting amp, calculate a gain factor about 100 to get you well into line level. You can put a pot in the amp circuit to vary gain like you have on OP2, but right now I can't figure out what your intention was on that 2nd stage gain circuit, can you please give a clarification there?
I would a simple tone stack after 2nd stage(you could add the graphic eq in later)

Power amps section: Design is typically done based on what load, wattage and power supply capacity is specified. Then you design from the power amp output back to the input line level.

Best regards, shanx
 
I made this schematic, please check it. I work with electronic every day, but never designed an amp. .....


Not to be insulting but really your best bet is to copy an amp you like. I really don't like op amps and there is a reason people use vacuum tubes.

A common beginner mistake is to assume you will only build one amp. So you build the "dream amp" as your first attempt. Bad Idea. Build a small tube based practice amp first and keep it 100% "stock" in the signal path. From what you say you might like a Fender Champ. I'd use a Webber 8" ALNICO "signature series" speaker and buy the "classic tone" transformer set from triode electronics. This combination is a true classic. Take care with layout, use coax wires and modern grounding elevated heaters. I built one and it just blows away the new Fender Champ 600. And it's dead quiet too.

Then you build the next amp. Maybe this time a Fender twin reverb. It is a much more complex circuit and physically larger amp. Again, like with the Champ the key is QUALITY speakers and quality transformers. Spend as much as you can on those parts

Bottom line, just a few items
(1) Build a small "practice" amp first
(2) Copy a proven design (until you have build a half dozen or more amps)
(3) Use quality parts where it counts (speaker and output transformers)
 
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Bottom line, just a few items
(1) Build a small "practice" amp first
(2) Copy a proven design (until you have build a half dozen or more amps)
(3) Use quality parts where it counts (speaker and output transformers)

Great tips, but just to add my 2 cents regarding tube choice. I recently try swapping tubes in my cousin's Vibro Champ, and I found that a new JJ 6V6 and a Svetlana or Electro-Harmonix 12AX7 (in the pre-amp socket, not the vibro socket) made a huge difference. The sound opened way up with rich lows and great mids and highs. For reference I also tried Sovtek 6V6, Sovtek and Chinese 12AX7's. The Chinese 12AX7 has a lot of gain which gives more overdrive but it was a bit muddy compared to the Svetlana or E-H, and the Sovtek's were cold with no bottom end.
 
I have built anax84.com P1 AX84.com - The Cooperative Tube Guitar Amp Project fir a friend that plays blues and jazz, as a combo with a Jensen P12 R. Only thing I did different was replace the 12AX7 with a 12AT7,

He fell in love with it immediately.

I had a P1 also. Used it for a while then modified it to the "HO" for more gain.

A P1 is notunlike a Fender Chan=mp exept that the Fender uses negative feed back and NFB greatly changes the amp's tone. The parts list and schematics ar very close. Different people would like one or the other. I have both

The Fender design with a little reverb added makes an "easy on the ears" tone that I prefer for practice. My HO is much more aggressive tone, is "touch sensitive and all that.

All that is different from a P1 to Champs is some resistors and other minor things but it makes a difference. This is why I said to copy a design. It will take a while before you can predict the tone of something you design.
 
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