Melxowtone Mods List/Instructions
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Mel x
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Melxowtone Mods List/Instructions
Do you still have this Eric? (as an email or whatever)
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crowquill
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Re: Melxowtone Mods List/Instructions
Just in case you didn't see the response over at HC - or for anyone here who's interested:
THE MODS
For those not familiar with electronics, this may seem daunting. Most of these mods are very simple though. For those of you who are familiar with pedal building you will recognise the circuit as a simple diode shunt to ground clipper. In fact, it has it's basis almost identical to the common Electra Distortion circuit, but set for more gain!!!! RAWR!! And nasty ceramic caps for intensity. That said, I have a thing for the simple self biased transistor circuit, and a little secret: there is a some sort of variation of it, in every Mellowtone pedal (dirt/gain pedals anyways, obviously). Don't tell anyone!
1. I WANT A DC JACK!
First, I highly recommend you just purchase a 1 Spot battery clip converter:
http://www.gearhounds.com/index.asp?...ROD&ProdID=349
They are cheap, require no work on the pedal, and won't void the warranty.
Or just put the pedal first in chain, and unplug the input cable when not in use. But if you really must install a power jack... follow these steps:
A) I will refer to this illustration of powerjack wiring from good ol' Beavis Audio
http://www.beavisaudio.com/techpages/StompboxWiring/
B) You will need to drill a hole somewhere in the enclosure, and mount the power jack. Orient the power jack so it appears as illustrated on the Beavis Audio site.
C) There are red and black wires from the battery clip which connect to 9v + and 9v -. Desolder these wires.
D) Solder the red battery clip wire to the far right lug of the DC jack as illustrated @ Beavis. Solder the black wire to the far left lug (in actuality you may leave the black wire in it's original location on the input jack, if you like, but for sake of matching it up to the Beavis illustration we will move it).
E) Solder a new wire from the far left lug of the DC Jack to the lug on the input jack marked "9v -" in the gutshot photo.
F) Solder a new wire from the location marked "9v +" in the gutshot photo to the center lug of the DC Jack. Be careful not to create any solder bridges on the circuit board. The wire should ONLY connect to the end of the 47k resistor (the one that is laying down flat).
G) DONE!
2. IT'S TOO DARK/WARM SOUNDING!
You can modify the tonality of the pedal by altering the input capacitor. The stock value is .1uF/100nF. For those not familiar, larger input caps = more bass and smaller input caps = less bass. Now, we don't have to remove and replace this cap on the board. We can place a second capacitor in series. Caps in series reduce the capacitance. So for this mod, you will want another capacitor- .1uf will get your a more neutral sound, .047uf should make it a bit brighter, .022uf should be quite bright, and based on my experience even smaller values will get you into some serious treble territory. I recommend trying .1uf and .047uf. This mod is easily reversable so it won't hurt to try out both.
A) Desolder the red wire marked "input" in the gutshot photo. Make sure that the resistor that attaches to this same lug of the switch stays attached (it's a pulldown resistor to prevent switchpops).
B) Solder one end of your capacitor to the switch lug. Clip the lead of the cap sorta short to keep things tidy and so it can't accidentally short on anything.
C) Solder the other end (again, clip it shorter to make it tidy) to the red input wire.
D) Done!
3. I WANT LESS GAIN!
This pedal is set to maximum gain in it's stock setting. If you want to try it with less gain, then this mod will work very similar to the input cap mod. You will need a resistor, values between 1k and 4.7k are pretty good. Try a few, to experiment.
A) Desolder the red wire from the input jack ground lug marked "Gain Ground".
B) Solder one end of the resistor to this input jack ground lug. Clip the lead shorter to keep things tidy. Make sure that the other resistor that attaches to this lug (the pulldown resistor) remains attached.
C) Solder the other end to the "gain ground" wire, again clip the lead shorter to keep things tidy.
D) Done!
4. I WANT AN EXTERNAL VOLUME KNOB!
Ok, you will ned a potentiometer, I recommened 100k Audio Taper, 16mm will be easier for you to fit in. You certainly could go to a ton of trouble to try and desolder the volume trimpot and attach the new volume pot by wires to the circuit board, but I can pretty much say ti will get very ugly fast. Instead what we will do is set the trimpot to maximum volume, and jsut add a new 2nd volume control externally. You will also need your knob of choice.
A) Desolder the wire marked "output".
B) If you are looking at a potentiometer from the bottom (shaft facing down), and you have the lugs pointing downward, they are numbered left to right - 3 2 1. If you need clarification google it!
C) Solder the red output wire to lug 3.
D) Solder a new wire from lug 2 on the pot to the lug on the stomp switch marked "output"
E) Solder wire from lug 1 of the pot to a ground point... you can use the ground lug on either jack.
F) Done!
5. I WANT A GAIN KNOB!
Easy. This works exactly like mod 3, for less gain, except you will use a pot instead of a resistor. I think a 5k pot will work best. 10k is probably more range than nescessary. 2k would be alright.... 1k would have very little range, but hey, if you have one on hand it cant hurt to use it. Basically you will solder the 'gain ground' wire to lug 3 of the pot. Solder lugs 2 and 1 of the pot (you can just crimp them together and make sure they are bonded by solder) with a new wire to the 'gain ground' lug of the input jack. DONE!
6. TONE CONTROL?!
If you do add an external volume control, you can also add a simple lowpass filter type tone control. I suppose there are all sorts of values of parts that work, but in the case of this pedal, I suggest a 50k pot and a .022uF capacitor as the parts you will need. You crimp and solder lugs 3 and 2 of the tone pot and solder a wire from them to lug 3 of the volume pot. Then you solder one end of the .022uF capacitor to lug 1 of the tone pot, and the other end of the cap to lug 1 of the volume pot. That should take care of it!
Email me if you have any questions or concerns doing the mods!
Bless!
-Eric
THE MODS
For those not familiar with electronics, this may seem daunting. Most of these mods are very simple though. For those of you who are familiar with pedal building you will recognise the circuit as a simple diode shunt to ground clipper. In fact, it has it's basis almost identical to the common Electra Distortion circuit, but set for more gain!!!! RAWR!! And nasty ceramic caps for intensity. That said, I have a thing for the simple self biased transistor circuit, and a little secret: there is a some sort of variation of it, in every Mellowtone pedal (dirt/gain pedals anyways, obviously). Don't tell anyone!
1. I WANT A DC JACK!
First, I highly recommend you just purchase a 1 Spot battery clip converter:
http://www.gearhounds.com/index.asp?...ROD&ProdID=349
They are cheap, require no work on the pedal, and won't void the warranty.
Or just put the pedal first in chain, and unplug the input cable when not in use. But if you really must install a power jack... follow these steps:
A) I will refer to this illustration of powerjack wiring from good ol' Beavis Audio
http://www.beavisaudio.com/techpages/StompboxWiring/
B) You will need to drill a hole somewhere in the enclosure, and mount the power jack. Orient the power jack so it appears as illustrated on the Beavis Audio site.
C) There are red and black wires from the battery clip which connect to 9v + and 9v -. Desolder these wires.
D) Solder the red battery clip wire to the far right lug of the DC jack as illustrated @ Beavis. Solder the black wire to the far left lug (in actuality you may leave the black wire in it's original location on the input jack, if you like, but for sake of matching it up to the Beavis illustration we will move it).
E) Solder a new wire from the far left lug of the DC Jack to the lug on the input jack marked "9v -" in the gutshot photo.
F) Solder a new wire from the location marked "9v +" in the gutshot photo to the center lug of the DC Jack. Be careful not to create any solder bridges on the circuit board. The wire should ONLY connect to the end of the 47k resistor (the one that is laying down flat).
G) DONE!
2. IT'S TOO DARK/WARM SOUNDING!
You can modify the tonality of the pedal by altering the input capacitor. The stock value is .1uF/100nF. For those not familiar, larger input caps = more bass and smaller input caps = less bass. Now, we don't have to remove and replace this cap on the board. We can place a second capacitor in series. Caps in series reduce the capacitance. So for this mod, you will want another capacitor- .1uf will get your a more neutral sound, .047uf should make it a bit brighter, .022uf should be quite bright, and based on my experience even smaller values will get you into some serious treble territory. I recommend trying .1uf and .047uf. This mod is easily reversable so it won't hurt to try out both.
A) Desolder the red wire marked "input" in the gutshot photo. Make sure that the resistor that attaches to this same lug of the switch stays attached (it's a pulldown resistor to prevent switchpops).
B) Solder one end of your capacitor to the switch lug. Clip the lead of the cap sorta short to keep things tidy and so it can't accidentally short on anything.
C) Solder the other end (again, clip it shorter to make it tidy) to the red input wire.
D) Done!
3. I WANT LESS GAIN!
This pedal is set to maximum gain in it's stock setting. If you want to try it with less gain, then this mod will work very similar to the input cap mod. You will need a resistor, values between 1k and 4.7k are pretty good. Try a few, to experiment.
A) Desolder the red wire from the input jack ground lug marked "Gain Ground".
B) Solder one end of the resistor to this input jack ground lug. Clip the lead shorter to keep things tidy. Make sure that the other resistor that attaches to this lug (the pulldown resistor) remains attached.
C) Solder the other end to the "gain ground" wire, again clip the lead shorter to keep things tidy.
D) Done!
4. I WANT AN EXTERNAL VOLUME KNOB!
Ok, you will ned a potentiometer, I recommened 100k Audio Taper, 16mm will be easier for you to fit in. You certainly could go to a ton of trouble to try and desolder the volume trimpot and attach the new volume pot by wires to the circuit board, but I can pretty much say ti will get very ugly fast. Instead what we will do is set the trimpot to maximum volume, and jsut add a new 2nd volume control externally. You will also need your knob of choice.
A) Desolder the wire marked "output".
B) If you are looking at a potentiometer from the bottom (shaft facing down), and you have the lugs pointing downward, they are numbered left to right - 3 2 1. If you need clarification google it!
C) Solder the red output wire to lug 3.
D) Solder a new wire from lug 2 on the pot to the lug on the stomp switch marked "output"
E) Solder wire from lug 1 of the pot to a ground point... you can use the ground lug on either jack.
F) Done!
5. I WANT A GAIN KNOB!
Easy. This works exactly like mod 3, for less gain, except you will use a pot instead of a resistor. I think a 5k pot will work best. 10k is probably more range than nescessary. 2k would be alright.... 1k would have very little range, but hey, if you have one on hand it cant hurt to use it. Basically you will solder the 'gain ground' wire to lug 3 of the pot. Solder lugs 2 and 1 of the pot (you can just crimp them together and make sure they are bonded by solder) with a new wire to the 'gain ground' lug of the input jack. DONE!
6. TONE CONTROL?!
If you do add an external volume control, you can also add a simple lowpass filter type tone control. I suppose there are all sorts of values of parts that work, but in the case of this pedal, I suggest a 50k pot and a .022uF capacitor as the parts you will need. You crimp and solder lugs 3 and 2 of the tone pot and solder a wire from them to lug 3 of the volume pot. Then you solder one end of the .022uF capacitor to lug 1 of the tone pot, and the other end of the cap to lug 1 of the volume pot. That should take care of it!
Email me if you have any questions or concerns doing the mods!
Bless!
-Eric
Last edited by crowquill on Tue Jun 16, 2009 11:07 am, edited 1 time in total.
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veteransdaypoppy
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Re: Melxowtone Mods List/Instructions
bummer. I thought this might be a thread explaining how to turn yer Electra Distortion into a Melxowtone. 
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Mel x
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Re: Melxowtone Mods List/Instructions
cheers crowquill 