DIY Effects

[LukeFRC]

[quote name='escholl' post='772303' date='Mar 11 2010, 11:52 PM']A larger input cap shouldn't affect the sound in a detrimental way, it will simply lower the cutoff frequency of the high pass filter that is effectively created by that cap -- in fact, as the pedal was designed for guitar, 0.1 uF is probably a good value to put in for bass, instead of the original. It is a good choice.

You've got the right idea that the 33k resistor affects the volume, however it works in the opposite way. So, if you wanted a louder volume, increase the value of that resistor. This is why when the connection to that resistor was broken, effectively raising the resistance very high, the gain was increased and the distortion occurred. By calculating a ratio of the input resistor (in this case 10k) to the feedback resistor (33k) the gain of the op-amp stage can be calculated, in this case the gain is roughly 3. If you want to increase it, you could try a 39k resistor in place of the 33k, for a gain of roughly 4, or a 47k resistor, for a gain of about 5. You could also try, say, a 47k pot in series with a 10k resistor, which would give you a variable output level.

In case you are wondering, the 6.8k resistor in series with the 0.01 uF cap is there to prevent that gain stage from amplifying too much high frequency noise above the usual audio spectrum, so that can stay as it is and does not need to be adjusted, although it could be if you felt like playing about with the high frequency response.

Also, if you are curious and did want a wet/dry mod, stick a 47k linear pot in place of where the 22k and 20k resistors are next to points A and D on the schematic. Not really needed though, I don't think.[/quote]

thanks!
Stuck a 47k resistor in, may make it smaller later as still a wee volume drop but it works a treat. I like the 0.1uF cap, makes it very bassey.

[LukeFRC]

so stuck a 100k resistor in the output op-amp and the volumes seem to match.
I'm really not sure what I've made here, the 0.1 cap on the input makes a massive massive difference.
It doesn't seem to have a massive amount of the top end shimmeryness that chorus seems to have, it's a lot deeper. Close to sounding like one of those lesley rotating speaker, yet with more stuff going on. I'm going to play with it and see what I think.

[url="http://www.diystompboxes.com/smfforum/index.php?topic=67908.0"]This thread is somone one else with the same problem making it work for bass and addressing it differently...[/url]


EDIT: wee play again. I do like it. As it has more bottom end it comes accross as more subtle. It doesn't 'shimmer' much and doesn't sound great on a guitar but it sounds good. Live and in the mix I'm think it possibly is a good sound.
I wonder... heres an idea.... is the chorus bit of the circuit very good with low end? If I put in a cap smaller that the 1uF in the feed from the op amp to the chorus bit of the circuit would it let give me a more trebly wet sound with the better bottom end i already have? Prob wont do it mind just interested.

Radansey: that A/B box is older than me!


EDIT No. 2: here's some mod's on a small clone [url="http://moosapotamus.net/THINGS/wavy.htm"]http://moosapotamus.net/THINGS/wavy.htm[/url]

Edited March 13, 2010 by LukeFRC

[escholl]

[quote name='LukeFRC' post='773321' date='Mar 13 2010, 01:21 AM']EDIT: wee play again. I do like it. As it has more bottom end it comes accross as more subtle. It doesn't 'shimmer' much and doesn't sound great on a guitar but it sounds good. Live and in the mix I'm think it possibly is a good sound.
I wonder... heres an idea.... is the chorus bit of the circuit very good with low end? If I put in a cap smaller that the 1uF in the feed from the op amp to the chorus bit of the circuit would it let give me a more trebly wet sound with the better bottom end i already have? Prob wont do it mind just interested.[/quote]

Try changing the 1uF cap going out of the first gain stage into the effect part of the circuit to something smaller, 0.22uF or 0.33uF perhaps. This won't give you more treble, but it will put less bass through the effect circuitry, and might clean up the sound a bit. Try the 0.33uF to start, if you feel up to it.

I've also just had a thought -- check the connections around the IC1a, make sure those components are all right on the board and there's no loose connections. Most people seem to complain the pedal has too much of a bass roll-off, as you've not found that to be the case but instead have found not enough treble, if may be that the pre-emphasis filtering network is not working correctly for some reason. This is just speculation though.

What I usually do in situations like this is, find all the mods you can, and try the ones you like the sound of. Then try some new ones, and just play about a bit -- it helps here if you know what you're doing though

[LukeFRC]

[quote name='escholl' post='773501' date='Mar 13 2010, 11:21 AM']Try changing the 1uF cap going out of the first gain stage into the effect part of the circuit to something smaller, 0.22uF or 0.33uF perhaps. This won't give you more treble, but it will put less bass through the effect circuitry, and might clean up the sound a bit. Try the 0.33uF to start, if you feel up to it.

I've also just had a thought -- check the connections around the IC1a, make sure those components are all right on the board and there's no loose connections. Most people seem to complain the pedal has too much of a bass roll-off, as you've not found that to be the case but instead have found not enough treble, if may be that the pre-emphasis filtering network is not working correctly for some reason. This is just speculation though.

What I usually do in situations like this is, find all the mods you can, and try the ones you like the sound of. Then try some new ones, and just play about a bit -- it helps here if you know what you're doing though [/quote]

It did have too much bass roll off. The 0.1 cap at the start sorted that though. If I get a chance to go to the shop on monday I may stick a 0.33uF. To be honest it sounds good so I'm not too bothered.



As another note, If anyone is using the breadboard big muff plan that was posted up here a few pages back it has some interesting differences (mistakes?) in the bottom right section. Look up a schematic and swap around two sets of resistors and caps.


EDIT: tried it all again, and yes will try that 0.33uF cap....or maybe reduce the 0.1 cap at the start to 0.066 or something.
EDIT 2: Put the 0.033 back in. Not as bassy but sounds fine. I think I may just leave it! Want to get these all finished!

Edited March 13, 2010 by LukeFRC

[LukeFRC]

umm help... made a big muff pi, everything looks like it should be working but it's not....

l[url="http://www.aronnelson.com/gallery/main.php/v/Gila_Crisis/Big_Muff/BMP.gif.html?g2_imageViewsIndex=1"]ayout: [/url]

possible problem with the transistors? using an audio probe nothing seems to get through the first transistor! any help would be great!

Transistor....BC239C

battery 8.25v
c - b = 6.12v
b - e = 0.47v
c - e = 5.86v

[LukeFRC]

ok those voltages may be useless, ill try get better ones for each pin relative to input...

[LukeFRC]

C= 0.21
B= 6.43
E = 5.33

which looks wrong to me!

EDIT 2: arrggh I give up. starting again with another layout that makes more sense and is a wee bit different but at least i know someone else has got it working!


EDIT 3: one day later and half a dismantled effect..... ahh the transistor to ground resistor being 390,000 ohms not 390 ohms may have something to do with that!

Edited March 16, 2010 by LukeFRC

[JackLondon]

Right, I haven't been here a long time,

2 Pedals are done :

First off we have a Tycobrahe Octavia

Here's the beggining of the cable spaghetti :

[attachment=45030:H_Inside.JPG]

Here we have everything soldered and ready to fire up :

[attachment=45031:H_Finished.JPG]

The front of the box, don't comment on the name as it was not my idea

[attachment=45033:H_Front.JPG]

It sounds very nice and can go from slightly overdriven to full on fuzz sound, the second footswitch is to switch the octave on/off


The second pedal is a simple looper, I won't bore you with the insides as everyone knows there's nothing exciting going on in there

[attachment=45036:L_Finished.JPG]


Tomorrow we have a booster pedal and possibly another fuzz. Stay tuned

[mancunianfox]

How do you do those labels Jack, they look all kinds of awesome!

[JackLondon]

[quote name='mancunianfox' post='778907' date='Mar 18 2010, 05:51 PM']How do you do those labels Jack, they look all kinds of awesome![/quote]

Fairly simple yet time consuming

This is how I do it :

1. Make a design wth the positions of all the knobs, switches, LED etc. I do it on MS Word and it works fine, I use a picture as a background, then add all the text on top and then position the hardware.

2. Print off the design, cut out, stick it to the box using masking tape and put all the hardware where it should be on top of the sheet to see how much space I'll have, if a pot or a switch needs moving I go back to the design, re-do it and then print it off again.

3. If the design is good I then punch the dots where the center of everything is to make the drilling easy, drill the holes and put the design on the box again, look under the light to see if the holes are centered. At this point it's also very good to know what sort of clear coat you'll be using, if it's water based that's fine, if it isn't then every area of the decal that is white will be transparent. If you want whie you can use water based clear coat or paint the top of the box white.

4. If all of the above is done I then print off the decal on this paper : [url="http://www.inkandmedialtd.co.uk/acatalog/Inkjet_Waterslide_Decal_Paper.html"]http://www.inkandmedialtd.co.uk/acatalog/I...ecal_Paper.html[/url] you are best off printing a couple in one go, if you're clever you can fit 3 x bb and 2 x b decal on one sheet so you can have 40 labels for £14, not bad.

5. Let the decal dry for about 1 hour and cut it out using a very sharp blade.
5a. At this point you have to decide how intense you want the colours to be, if you want them as they apper on the label straight from the print I suggest painting the top of the box white ( 1 coat is enough ) because if the box is dark the colours will darken once the decal is dry.

6. Wash the box thoroughly with washing up liquid and immediately dry with paper towels, avoid touch the box with your fingers ( they are greasy )

7. Put the decal in to a bowl of water, leave it for 1 minute, pick it out and apply to the box, don't rush as they are easy to rip. Whilst the decal is wet you can move it about to give you perfect fit but be quick. Once you have a perfect position use a credit card to get rid of all air bubbles so it's nice and flat. Leave the decal to dry on the box overnight, if you have some paper not sticking on the very edge of the label don't worry it will after next step.

8. Now it's time to apply clear coat and I strongly recommend doing it to protect the decal. First of all put on your face mask, this stuff smells like mad and if you're doing it indoors open all available windows to allow proper ventilation. I use either water based or normal chemical clear coat. I have put 3 coats on each box with 2 day gaps between coats ( It's not paint and it doesn't dry so quickly ) and leave it for 7 days after the last coat, if you use chemical based clear coat then I would recommend leaving it for good 12-14 days as this stuff takes ages to dry even in very warm conditions. Try to stay away from the box, I know it will be tempting to touch it and it will feel very dry to your hand but trust me it isn't, at this moment patience is a must and if you don't have anything to do go and play on yer bass!!!!!

[color="#FF0000"]Important[/color] If you're using a white box, be very careful with your clear coat as it might dry tobacco yellow if you're not careful enough. do very thin coats, not heavy and keep the box away from sources of heat, normal room temperature is fine.

9. Once it's dry I wait until the last possible moment to touch the box, I get everything ready, put the sockets, switches and LEDs in and then use a very soft camping mat that you can buy in poundland for a quid, works a treat and protects the box while you're moving it around during assembly.

10. If you so far haven't swore gazzilion of times, had to re-do the whole thing or made a very small chip then give yourself a pat on the back because you were miles better than me.


Alternatively if you can't be bothered then feel free to PM me and I might do it for you if your quick enough


Simples


Cheers
Jack

[mancunianfox]

Cheers for that. Done painting and clear coating but not decals yet. Will be giving this a go...very detailed description. Those LED bezels are nice as well. Suprised you don't see those on more boutique offerings really.

[JackLondon]

Yeah those LED bezel are really cool, I know Max (Silent Fly) puts very nice ones on his boxes and yes it is surprising that other manufacturers don't put them on considering that they are only about 50p! Good luck with the decals and if you need any help give me a shout

Cheers
Jack

[LukeFRC]

I like the octavia. how do you fasten the board insidde the enclosure?

I am so tired of this big muff... it works up to the 3.9nF cap in the tone curcuit and also the whole signal seems a wee bit clean!

[JackLondon]

I'm using those plastic standoffs that are dirt cheap but do the trick! I have some metal ones in case a pcb can be grounded through enclosure!

[LukeFRC]

success! It worked momenterally! something to do with the pots..... the curcuit seems fine now phase two of problem solving!


Edit 1: ah i have two lin and one audio pots rather than the other way around, that probably makes a difference

Edited March 19, 2010 by LukeFRC

[JackLondon]

Instalment number 2 as promised

Here we have a simple signal booster, the first pic of the inside :

[attachment=45179:T_Wiring.JPG]

2nd Pic of the finished product, front of the box, I couldn't help naming it properly in relation to guitarists

[attachment=45180:T_Front.JPG]



2nd on the list is a clone of Fuzz Face, it has a full on fuzz sound, it will require a bit more tweaking with the variable resistor but that's when there's not many people around.

Checking again how it will all fit :

[attachment=45181:FF_Check.JPG]

Everything wired up, waiting for transistors

[attachment=45182:FF_Wiring.JPG]

The front of the box, I really like this one the most

[attachment=45183:FF_Front2.JPG]



So far so good with the building in general, however I am not happy with my wiring and especially that I have another 3 effects to build that will have a lot more wires and it includes the small clone chorus with stereo mod I need to work on getting all those wires neat and tidy, I was thinking of putting 4 cable tie bases and feed all the wires through there, might be a bit tricky but should work I reckon. Any tips or ideas on this ?

Stay tuned for more coming next week once another batch of enclosures is ready

Cheers
Jack

[Simo]

After being inspired by all the DIY effects pedal builds I've seen on here and on other forums lately I decided to give it a try myself... although it's a guitar pedal I'm afraid I was looking for an overdrive pedal to give my Blackstar HT-5 a little more gain, so I ended up going for a Tube Screamer replica, 'Das Screamer' from Music Ding in Germany...

[url="http://www.musikding.de/product_info.php/info/p1618_The-Screamer---Overdrive-kit.html"]http://www.musikding.de/product_info.php/i...rdrive-kit.html[/url]

I'm going to make a start wiring it up this week when I find some time. As you can see, the artwork is done oh, and in case anyone was wondering where the name came from, then click here... [url="http://www.youtube.com/watch?v=ElTgT35fZWs"]http://www.youtube.com/watch?v=ElTgT35fZWs[/url]

'Arm' and 'Disarm' is for the switch, which switches between symmetrical and asymetrical diode clipping, 'Jihad' is the for the led and the on/off switch is in the centre of the bomb.

Edited March 20, 2010 by Simo

[JackLondon]

Nice one Don't get carried away though, it's a very grabbing hobby and I think you'll have enough of other things to do

[Simo]

haha, yeah you're not wrong there

[escholl]

[quote name='LukeFRC' post='775583' date='Mar 15 2010, 07:36 PM']C= 0.21
B= 6.43
E = 5.33

which looks wrong to me!

EDIT 2: arrggh I give up. starting again with another layout that makes more sense and is a wee bit different but at least i know someone else has got it working!


EDIT 3: one day later and half a dismantled effect..... ahh the transistor to ground resistor being 390,000 ohms not 390 ohms may have something to do with that![/quote]

Sorry, I've not been about -- did you get it working in the end?

[LukeFRC]

eventually! turned out that the resistors were wrong and there was a loose connection in the sustain pot.
It works. not exactly amazing, i think i may have wired some pots backwards but its good enough, i only need one one or two sounds from it.

[LukeFRC]

ta-dah!

It's not perfect. the sustain knob is backwards for the muff part, the chorus has a massive volume drop and i blew 2 LEDs...but it works!



and yes its a mess inside, and yes my soldering iron did have an argument with one of the jack sockets!

Edited March 21, 2010 by LukeFRC

[escholl]

[quote name='LukeFRC' post='782049' date='Mar 21 2010, 08:23 PM']and yes its a mess inside, and yes my soldering iron did have an argument with one of the jack sockets![/quote]

That's what the case is for -- so no one can see!

Soldering is a lot like learning an instrument. You never feel like you're getting any better at it, until you look back at one of your old projects and have that moment of "wow, i am so much better now!"

Also, my suggestion for next time would be to try some wire looms, as seen in the photo attached. It doesn't really matter, but it just makes things look neater

[LukeFRC]

I think next time I will be putting them one effect per box! Way way too many different leads. I don't really mind too much about the mess.

The volume drop in the chorus confuses me, I had stuck a different larger resistor on the out op amp to compensate, stuck it in and its very quiet. Upped it again (destroyed the contacts on the PCB in the process ) and its still too quiet. Im loosing signal somewhere, I may check it over to try find the problem. My guess would be a loose connection.

Soldering is a funny one. I was using maplins Lead free silver solder for most of this. I ran out and the local electronics shop sold me some 60/40 tin lead alloy stuff- totally different melting point, so therefore tottaly different technique. Going from the trumpet to the french horn maybe

[bobbass4k]

[quote name='LukeFRC' post='782249' date='Mar 21 2010, 11:17 PM']I think next time I will be putting them one effect per box! Way way too many different leads. I don't really mind too much about the mess.

The volume drop in the chorus confuses me, I had stuck a different larger resistor on the out op amp to compensate, stuck it in and its very quiet. Upped it again (destroyed the contacts on the PCB in the process ) and its still too quiet. Im loosing signal somewhere, I may check it over to try find the problem. My guess would be a loose connection.

Soldering is a funny one. I was using maplins Lead free silver solder for most of this. I ran out and the local electronics shop sold me some 60/40 tin lead alloy stuff- totally different melting point, so therefore tottaly different technique. Going from the trumpet to the french horn maybe[/quote]

People are worried about dying early so lead based solder has become quite a taboo. Personally i don't mind losing 5 years off my life if it gives me better solder joints. I can't stand lead free stuff, doesn't melt consistently and goes grainy for no reason.

I have far too many opinions on solder