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Re: Reverb power supply

Posted: Sat May 16, 2020 9:06 am
by eatyourguitar
220uf good for about 200mA. if you don't have regulators but you have big ass NPN PNP you can make a pass transistor that works like a regulator. personally I would solve this with 2000uF caps a 1/2 watt resistors 0.1 Ohms or something. maybe even two stage RC low pass filter 1000uF each. I have all kinds of chokes but those are more expensive than regulators. if you salvage chokes then that would be the only cheap way.

Re: Reverb power supply

Posted: Sat May 16, 2020 10:29 am
by crochambeau
eatyourguitar wrote:220uf good for about 200mA.
Plenty of current for a TL072, unless the previously linked schematic is not involved.

Re: Reverb power supply

Posted: Sat May 16, 2020 2:08 pm
by Ben79
Thanks guys, I think I'll probably use a couple of regulators - I've just looked them up and see that there is a special kind for the negative rail.

That schem is, I think, just chopped from a Marshall amp so I'm wondering if it can function unmodified as a standalone unit....

Looking at it, do you think the input and output are ok as they are ie. guitar signal friendly at the input and amp friendly at the out?

There's no provision for any mixing control in the schem.....any ideas for something simple to solve this? Could it be as simple as replacing the ground at the 5k pot with the dry signal, maybe through a simple booster to match the levels?

Re: Reverb power supply

Posted: Sat May 16, 2020 8:24 pm
by eatyourguitar
yes LM317T LM337T. I lifted it from the MFOS design which is pretty close to the texas instruments datasheet. here is a picture of my LM317 LM337 supply. you don't really need the trimmer if you want to save $2. ham people build these on copper clad. there are many low budget hacks. don't short the heatsinks to each other.

https://eatyourguitar.myshopify.com/col ... -bus-board

Re: Reverb power supply

Posted: Sun May 24, 2020 6:07 am
by Ben79
Here's a little demo of the reverb....

https://soundcloud.com/momsazombie/aflicker


Re: Reverb power supply

Posted: Sun May 24, 2020 7:53 pm
by eatyourguitar
I love the way you jam. the reverb works good then.

Re: Reverb power supply

Posted: Sun May 24, 2020 11:40 pm
by crochambeau
Yeah, that sounds nice!

Re: Reverb power supply

Posted: Tue May 26, 2020 12:47 pm
by Ben79
I'm stoked with it. Still haven't got the 10k pot for the fuzz yet but I'll post a pic or two once it's all buttoned up....maybe do a demo of the fuzz too.