looking for a diy guitar amp.

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
It looks to me as if the circuit you posted will work OK. But half the fun is building it and trying it out, most of the parts are cheap enough that you can always 'upgrade' your design if not satisfied.

I like the idea of breaking it up into three sections, pre-amp, power-amp and power supply. You can test each one.

Whatever amp you build, if you know the power level you are looking for (e.g. 60W) then start by making a good power supply. You likely won't have to make any changes to it and it would work with different amplifier options. The link you were given above to ESP is a good place to start looking for a power supply design.

Then you can add the power amplifer. You could select from many options on this Forum such as DX amplifier if you want to build out of discrete components, but the suggestion of a chip-amp is also very good as it is a simple approach.

Then focus your fun on the pre-amp part, the most interesting part for different sounds.

Edit: if the distortions/effects really gets you interesting in doing more:
http://www.montagar.com/~patj/gindex.htm

Good luck.
 
You can buy ready made amplifier modules at many places.

If you buy it ready made then you know it has been built, tested and aligned professionally.

Even ebay has a wide range of amp modules from MOSFET to valve to hybrids.

Having said that you can get great satisfaction from building your from scratch. The problems start when it doesnt work because you made a mistake or you have a built one that doesnt work anyway !

I design and build my own but I have 30+ years experience.
I thoroughly test mine out on prototype board long before I go anywhere near a PCB.
 
Guitars needs a very heavy duty amplifier

they will play sustaining tones and distortions...this sucks a lot from the supply that must be huge... also huge heatsinks to the power amplifier and several output pairs... double or tripple them.

All amplifiers can do the job, you will need to increase (at least double) the output transistor quantity, double the heatsink size, double the transformer power, double the condensers and double the rectifier.

Also install big heatsinks to the drivers and be happy!

Also do not bother with distortions of other specifications...as you will use it distorting..if the amplifier produces some by itself will give you some nice colouration that may result you building a champion amplifier and your friends will try to have one alike yours.

Music reproduction (not heavy metal or heavy rock..a special style of music) is average.... guitar will sustain clipping for long, long time...normal amplifiers, from the box..will burn!

Build a Dx Amplifier... increase the things i told and you will have a nice powerfull amplifier, perfect for guitars and will survive your childrens and may be playing while your granchildrens grown up.

Maybe Rodd Elliot (ESP pages) have something good..but i have not tested... i cannot say yes or no....mine is guaranteed... and a DIY for free stuff..tested by by noisy daugther that plays guitar plugged into a Dx Amplifier, the standard one.

If you're knew into the forum...here you have the Dx Amplifier...made to be reliable even when monsters use it... (guaranteed for music as standard)... tested together guitar too, and survived without any modification...but they are needed for long time shows.

http://users.tpg.com.au/users/gerskine/dxamp/
 
If you are going to go onward from a schematic only, I suggest you take a look at the commercial designs instead. The Internet is full of such schematics.

Make a small list of amps you like and take a look at their circuitry to see what does what. You will have a much better understanding of what kind of an amp/circuit you need.


Edit: I have built the 60W guitar amp in question. In short: Stay away from it. Old-fashioned design that sounds terrible and doesn't work right without tweaking.

Rod Elliot's power amp is a somewhat good design but the preamp is not worth a dime unless you want to play with pristine clean sounds only - which turn into obnoxious buzz when the preamp gets overdriven.

To this day I haven't found DIY examples of solid-state guitar amps that could rival most of the commercial designs. Prepare to build some mighty complex stuff if you want the amp to sound good.
 
kostaz8 said:
All of you told me about some great sites to look for.But what amp of all these do you suggest to build?


teemuk said:
Rod Elliot's power amp is a somewhat good design but the preamp is not worth a dime unless you want to play with pristine clean sounds only - which turn into obnoxious buzz when the preamp gets overdriven.

As I said, not everybody likes 'fuzz' created by back-to-back diodes, but Rod Elliott's design is well documented, robust and proven. You can get PCBs from him, and support will be easy to get. This recommends it to a beginner. It has a useful tone stack and the clean sound is ideal for use with an external tone shaper such as the SansAmp or the cheaper Behringer V-amp

w

Promises, promises...
 
Simple and well-supported (assuming you buy his PCB) - that's about it.

But to be frank, the preamp of Rod's amp is weaker than most preamps you can find from commercial "practice amps" of 10 - 20W range. Most of those at least have "semi-individual" overdrive and clean channels with some dedicated voicing on each. And that tonestack circuit is about as standard as it can get. Nothing in that design is a feature that would be really worth of mentioning. Basic, cheapie practice amps (i.e. such as this http://www.drtube.com/schematics/marshall/8020.pdf) easily beat it 10-0. And that is not even an achievement. Both are still horrible.

Back-to-back diode clipping can work wonderfully but it requires careful filtering pre and post. That's where all the tone comes from. Rod's preamp, on the other hand, has a bandwidth comparable to a HiFi amp (e.g. -3dB bass rolloff at about 40 Hz). Bandwidth like that is ridiculous and will guarantee buzzy and muddy clipping tones. Sorry to say it, the whole design is a pathetic example of a guitar preamp. The circuit can only do decent cleans - and that is something 99% of all those simple practice amp preamps can do as well.

And what's the point of that? Most of those preamp -type pedals (such as the aforementioned SansAmp) can interface directly to power amp. It somewhat makes using other, "clean" preamps kind of moot unless those preamps have features and effects like chorus, reverb, FX loop, graphic EQ etc. Those that the other preamp lacks. ...Then again, you hardly find that stuff from simple designs.

I still feel that the best choice - although not the easiest one - is to build one of those commercial circuits that have a bunch of useful features and prove to be muc more enjoyable in the long run. Yes, those circuits tend to be complex but that's the price you got to pay.
 
teemuk

'Simple' and 'well-supported' are attributes which you belittle too readily.

'standard' - yes, BEFORE 'non-standard' most people like to have 'standard'. When we have explored standard, THEN we move on.

teemuk said:
Both are still horrible.

You have said a lot of negative things, but have not made a single positive recommendation. Which circuit do you suggest?

w
 
Like I wrote earlier: There are plenty of schematics of commercial guitar amps that can be found from the Internet. Most of them beat the simple DIY designs.

There is no best circuit and none of us can have a slight idea what original poster is looking for.

He doesn’t specify any features he is looking for, or any output power range, or any idea of “tone” the amp should have (e.g. references to certain amps, bands or guitarists or something along those lines). “I want to build a guitar amp” doesn’t give much to work with so throwing around ideas and personal preferences is a bit vain, don’t you think?

What comes to topic, based on my own experiences, I simply can’t recommend any of the preamp designs presented in this thread. However, since you are interested, if it was up to me, I would likely go on building something along the lines of either Gallien-Krueger’s ML250, Hughes & Kettner’s Vortex 80 or Pearce’s G1R - at least partially. They are proven, versatile circuits which have characteristics I like. Personally, I like to cook my own designs, though.

As an additional note, Runoffgroove.com’s pedal designs seem to be fairly popular choices for preamp for DIY projects. Most of the threads like this seem to escalate into recommending them and a Gainclone.
 
Kostasz8,

The aficionado's for guitar amps invariably build something with vacuum tubes. This is because they produce the 'right' kind of distortion. Sooner or later most guitarists want to try a tube amp.

I would give this option serious consideration.

I don't know if you have any interest in tubes ? You have to follow adequate safety precautions when constructing them because high voltages are required. But construction need not be very complicated, in fact in many cases you don't even need a pcb to build one. If this is of interest, you might post your enquiry into the tubes forum instead of this one. Some links that might whet your appetite:

http://ax84.com/ (you can buy kits, or pre-cut chasis etc.)
http://www.frontiernet.net/~jff/ (the moonlight amp looks like a good DIY option)

In terms of finding what kind of amplifier you want, I'd go and ask some guitarists (my apologies if you are already an expert). Or get a book such as
"Guitar Amplifier Handbook - Understanding Tube Amplifiers and Getting Great Sounds" by Dave Hunter (there are a few used on Amazon.com)

and don't knock the cheap Chinese imports. If you search around on the web you might find a nice tube amp for very little cash and it could be a good starting point for some home-modifications if ready built or a kit.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.