DIY low power guitar amp

[Domin]

Hi! I found some videos of Noisy Cricket amp and i like it but i wanted something louder...is there some chip (3-5W) that sounds similar to LM386 when overdriven?

[tonyharker]

If you add a push-pull output stage to the noisy cricket as here https://joefreeman.weebly.com/lm386transistor-amplifier.html then you should get about 4 watts into 4 ohms.

[Domin]

And LM386 with variable gain and some chip? Can that LM386 with gain on max overload and destroy another chip?

Push-pull stage doesnt look bad but will it work with same values with 9V?

[iainpunk]

And LM386 with variable gain and some chip? Can that LM386 with gain on max overload and destroy another chip?

no, most if not all power amp chips have input impedance high enough that no significant current will go in its input, essentially ensuring it won't get fried also, check the Acapulco Gold pedal

Push-pull stage doesnt look bad but will it work with same values with 9V?

yes, same values are alright

cheers

[Clint Eastwood]

And LM386 with variable gain and some chip? Can that LM386 with gain on max overload and destroy another chip?

Push-pull stage doesnt look bad but will it work with same values with 9V?

With 9 volts, adding the transistors is not going to get you much more power. Certainly not 3 to 4 watts.

[Domin]

And you mentioned EQD Acapulco gold...i made a copy of it, is there any way to make into a 0,5w amp? Just take out volume pot, put bigger cap and after cap speaker?

[GibsonGM]

I don't think so, Domin.    You must increase the supply voltage within the rating of the 386 to obtain more output power.  You can find that by looking up the data sheet for the model 386 chip you are using..some are 12v, some are 18v. Most existing designs are getting 'the most out of it' that they can.   You can add more GAIN to the 2nd stage with a cap across pins 1 & 8, but that will only cause more distortion. 

Mind that if you ask the 386 to dissipate more than it is rated for (also in the data sheet), it will burn up.
(LM386N) 1.25W
(LM386M) 0.73W
(LM386MM-1) 0.595W

That is why they are using the slave transistors to provide more output power in the above circuit.   If you like the 386 sound, you can use that as the input for a 'chip amp', too, running at a higher voltage to obtain more output power! 

[Domin]

I was thinking about that the second stage wont have enough gain...Here is problem to get the LM386-N4 so i use normal LM386-N1)...You mean LM386 as an preamp into another amp? I was thinking about LM380 or TDA7052

[GibsonGM]

There are a few others who really use the 386 often like this - they may see this and give you better advice.  You could search for "LM386 preamp" on here and in a search engine for more info on other designs.   I know 'pinkjimiphoton' has played with these quite a bit.   I don't care for them too much, I can never make much of use of them that is stable.

Yes, my thought was use the 386 for a preamp, into one of the TDA amp chips...because if you can get the 386 sounding right, it can make a good clipped sound (as I mentioned, those other designs).     They're not made for more than what we usually do with them - a low level driver for 'indicators' or toys...

There are VERY many posts about LM386 on here using the "search" function. You can learn more about good, and not good, uses for the 386.
Example of one:
https://www.diystompboxes.com/smfforum/index.php?topic=126501.msg1209858#msg1209858

[Domin]

Thanks a lot

[Domin]

I came up with this idea too...DAM Dark Meathead into TDA7052 with buffer between it

[marcelomd]

May I suggest a cheap TPA3118  module? It's 60W, very small and very clean.
You can put anything in front and not worry about power.

[Domin]

60w is too much, i live in flat and i can even hear neighbors talking :/ So i need something with low power and compensate it with bigger speaker...but i would like to crank 60w to max

[marcelomd]

Actually it's 60W with 24V into a 4 Ohm speaker (or was it 2?). You can use a smaller supply.

I use it with a 24V PSU into a 16Ohm Celestion. I think it does a bit more than 15W cranked.

[GibsonGM]

The beauty of a module, whether it is 60W or 15W (power supply dependent!), is that you can play with many preamps and adjust until you get what you want!

[printer2]

https://www.ebay.ca/itm/284565336707?_trkparms=ispr%3D1&hash=item42416a7283:g:s~8AAOSwZ3JeaJ~5&amdata=enc%3AAQAGAAACkPYe5NmHp%252B2JMhMi7yxGiTJkPrKr5t53CooMSQt2orsSwcmzw5CLtzTE60FqHcnq2CVCm%252Fg0gzQvA63rRnLGuNiKJJYYH5zdI5GovpMNe9Hysmdd6z1AI0VzhrH%252FpadtKV5TsZUI22IeeIh9Yi9z7CsHqWjXhwKQDEWPHdA0hfrZwrjW%252F6I6S7xknhEvn6i9ffMYjn0QF8OF4iMGSxoaqUUyTulEhrvZPPPrz3Vsp3XrrSlLNJz9RQZqoI3M1fmJDHVVfV%252FmrFgu%252BOomyc5aaSvTw5oIuLDXYuKtSOeyrbUR3Ta0GxlZCDm829mNXZX7M8gnZsGQFlTAPl1KTXC3Ms2QF3I8fys6hu2m%252FwP4xSlKcGDrO0xK3Xqdp2%252B8Jx3QaOiSiy83p%252B3hAfsI5CyE9Hb0iRA%252FbMfpj1z3rB4SJr8gx9mKRROhfSktPPb1s8twhdJPrLYkU6oEKUAKCi7SuBIKYSzP5kaTDq1A6QdA0X1f9QyF%252BAnUQ873MIi97OtopmvoCc89JQ1%252BI35%252FgOg5a7u7hGFg08N3Axj1BYc36IM%252Fa1QlGIknN18qAGMIrcKW6zTtrsRkkArHBOdHOzxaQ85UVECn7nLsrD%252BNSYLhu8LONb%252Bi%252BThi%252F8TL068qczJy2Tgw%252FABgmN%252BJf91gu64ljBUeYCp5lKGBhAqCDIxtK%252BTnThQx%252BDI8sPJpC3OJ5okXlD5WVH9NcPuqqYBy3Rbu9ZuU56M2BGw%252F7torbw%252Bx%252F7eqySP5QQ6tNfyeSEaNHIq7ArxJGBvnGbw%252FPna%252BEdh0VsvLlhK3rv5XtphvnbBcn4U4pnA6LjQttmu2AmVqVFBPw5GhJ7sF8OF6sAlw0vKURvUS6OM9LPYJGv4mZ0gn7L7K%7Cclp%3A2334524%7Ctkp%3ABFBMxIeF991f

As an example. Just need a volume control and use a pedal for preamp.

[GibsonGM]

I've used TDA2030's for a few different things - they work well.  You can buy them separately to DIY, or a module like you showed, printer2.   If you buy them as 'parts', be careful as there are quite a few fakes out there, it seems.  (Use a well-reviewed seller)

[anotherjim]

This topic keeps coming up, but as PRR always tells us, a proper 12" open back guitar speaker is plenty loud with 1W power and if you can hear neighbours speak they will probably hear you. Amp power really doesn't mean much in terms of loudness without planning the speaker and cab. A repurposed hi-fi speaker is less sensitive and needs more power and if 1W isn't loud enough you need to go to 10w to double that loudness. 2W power is only +3dB above 1W.

[Domin]

I have 20w bass amp with 8" and on 4/10 its loud enough, so with guitar i wont need that much power for sure and for practice and diy is 1w or 3w ok And what about those BS Fly 103 extension cabs? If i just plug preamp? It use some sort of PAM poweramp

[GibsonGM]

It might sound nutty, but if you have a bass amp with an 8" speaker, couldn't you use that for guitar as well? I mean, you might need an eq pedal or something to get what you want, but -      I used to record using a friend's Peavey bass amp because it had EQ - sounded great, and it had bigger speakers. Didn't make any difference that I could hear at low volume levels.

Otherwise - maybe build a couple of 386 circuits to see what they can do, and learn their limitations.  If you need more level, then try a power amp module.  1W, 3W is fine for practicing alone.    Can you post a link to the BS Fly extension cab?