#1
The title is kinda self explanatory. I'm a bass player who loves fx, but hates the lack of options when buying true, made for (or even works for) bass effects pedals. I have no experience building or modding pedals, but really want to learn and thought this might be a good place to start. So I have a few questions:
What exactly is the difference between guitar and bass fx (I mean physical diffeneces, not "they're made for lower frequencies.")?

and

How could I change between the two?
Quote by C0_0kie
guitar solo - "meh, every song got one"
bass solo - "OMGZ0R U IS PRO MENZ"


Quote by lucertia.
fapfapfapfapfapfap


burgerburgerburgerburger


Quote by DeAd-RiP
Sir I would like to sex your bass.
#2
Basses put out a higher voltage than guitars. A guitar's amplitude peaks at about 100mV. Basses, if I remember correctly, peak at about 500mV-1V.

The reason some pedals (even guitar amps) can't be used for basses is because the higher amplitude can over-load the pedal/guitar amp. Some pedals, however, can safely be used with a bass (flangers and wahs are the only ones I know of).

For your first project, you could get a Crybaby Original and replace the sweep cap with a .068-ish cap. Viola! You now have a Crybaby Bass Wah. That's the only difference between the Originals and Bass Wahs, btw. So doing this saves you a big chunk of money.
#4
Would that work with a q-zone? It's a cool concept and almost the same wiring as a crybaby (I think). Plus, I already have (or will have. should arrive in the mail any day now) a Morley PWB. Though that would be a cool one to mod like that also. It works for bass (Cliff Burton used it), but it sounds like it saps a lot of low end.
Quote by C0_0kie
guitar solo - "meh, every song got one"
bass solo - "OMGZ0R U IS PRO MENZ"


Quote by lucertia.
fapfapfapfapfapfap


burgerburgerburgerburger


Quote by DeAd-RiP
Sir I would like to sex your bass.
#7
so where can I get sweep caps?
Quote by C0_0kie
guitar solo - "meh, every song got one"
bass solo - "OMGZ0R U IS PRO MENZ"


Quote by lucertia.
fapfapfapfapfapfap


burgerburgerburgerburger


Quote by DeAd-RiP
Sir I would like to sex your bass.
#8
I mean the cap on the emitter of Q2, before the resistor. I always called it the sweep cap.

edit: smallbearelec.com sells them. Look for a poly film .068mF

edit2: Here. http://www.smallbearelec.com/Detail.bok?no=163

Choose .068 from the drop-down menu.
Last edited by Invader Jim at Sep 7, 2008,
#9
so is that all I need to do? to convert between guitar and bass pedals? change the sweep cap and possibly the input and output jacks (if it's not a wah? BTW, what kind of jacks should I use?)
Quote by C0_0kie
guitar solo - "meh, every song got one"
bass solo - "OMGZ0R U IS PRO MENZ"


Quote by lucertia.
fapfapfapfapfapfap


burgerburgerburgerburger


Quote by DeAd-RiP
Sir I would like to sex your bass.
#10
A 'sweep cap' is just a capacitor. I call it a sweep cap because it determines the sweep range of a wah pedal. For a Crybaby-style wah pedal: yes, this is all you have to do. Just change that one cap.

You don't replace the jacks... Jacks are jacks. Makes no difference as long as it fits...

I'm not too familiar with bass FX and stuhf. It may not be this simple on all pedals. It's not just a "If it works here, it'll work on this too" kind of thing.
#11
I think I'm doing the mod on the Morley PWB. Also, I found schematics for the PWB and the PWA (as far as I can tell, the closest thing to a made-for-bass equivalent). Imageshack is being a b**** so I'll just post links:

PWB: http://www.schematicheaven.com/effects.htm

PWA: http://www.morleypedals.com/downloads.html

Edit: oh wait... I forgot to say what to do with the links... I was hoping that might help you guys figure out what I need to change
Quote by C0_0kie
guitar solo - "meh, every song got one"
bass solo - "OMGZ0R U IS PRO MENZ"


Quote by lucertia.
fapfapfapfapfapfap


burgerburgerburgerburger


Quote by DeAd-RiP
Sir I would like to sex your bass.
Last edited by kugelspot at Sep 8, 2008,
#12
this doesn't fix that guitar pedals generally cut out a lot of the lower frequencies (guitar doesn't use them much, and it mostly just muddies up the sound), however, with bass, you won't be heard, ever.
#14
ya, but how would I change the voltages on the morley?
Quote by C0_0kie
guitar solo - "meh, every song got one"
bass solo - "OMGZ0R U IS PRO MENZ"


Quote by lucertia.
fapfapfapfapfapfap


burgerburgerburgerburger


Quote by DeAd-RiP
Sir I would like to sex your bass.
#16
The high output voltage only really applies to active bass pickups. Passive ones have a low output, just like guitar pickups. A guitar pickup can have a high output too, if it's active or highly wound.

For years, the only pedals bass players could use were guitar ones - distortion, wah, everything. A big muff doesn't break if you put a bass through it, nor does a volume pedal/phaser/any pedal.

In my experience of pedals, the main problem is that guitar pedals filter out the bass frequencies.
In the bass chat:

<Jon> take the quote of me out your sig plx
<Jon> i hate seeing what i said around lol


Leader of the Bass Militia PM to join!



And now on BANDCAMP!


Officially the funniest member of the Bass Forum.
#17
^ I dunno... my Crybaby squeals like a dying rooster with a bass plugged into it.
#18
Quote by Nutter_101
the main problem is that guitar pedals filter out the bass frequencies.


That was the whole point of the mod
Quote by C0_0kie
guitar solo - "meh, every song got one"
bass solo - "OMGZ0R U IS PRO MENZ"


Quote by lucertia.
fapfapfapfapfapfap


burgerburgerburgerburger


Quote by DeAd-RiP
Sir I would like to sex your bass.
#19
Sorry I just noticed Nutter's post

Quote by Nutter_101
The high output voltage only really applies to active bass pickups.


But I use an active bass.

Quote by Nutter_101
In my experience of pedals, the main problem is that guitar pedals filter out the bass frequencies.


How do I fix that
Quote by C0_0kie
guitar solo - "meh, every song got one"
bass solo - "OMGZ0R U IS PRO MENZ"


Quote by lucertia.
fapfapfapfapfapfap


burgerburgerburgerburger


Quote by DeAd-RiP
Sir I would like to sex your bass.
#20
Depends on the pedal. All I know is that somewhere in there is a high-pass filter. Change it to a low-pass filter. Something like that. Just look at a schem of a pedal you wanna mod, locate the high-pass filter(s) and change them to low-pass.

I'm pretty sure that's about it, but apparently I'm not as smart as I thought.
#21
On simple boosters and such the only filter is the input filter... all you really need to do is deal with them. The output cap is strictly for blocking DC and should not affect sound.

On other pedals look for resistors and caps either in series or in parallel. These are either high or low pass filters.

You don't need to change a high pass filter to low pass all you need to do is adjust how much highs are going through. aka not as much for bass.
#22
how do I change that?
Quote by C0_0kie
guitar solo - "meh, every song got one"
bass solo - "OMGZ0R U IS PRO MENZ"


Quote by lucertia.
fapfapfapfapfapfap


burgerburgerburgerburger


Quote by DeAd-RiP
Sir I would like to sex your bass.
#23
The pedal came in the mail a couple days ago. I've been fooling around with it (it's hard to not make it sound like ass when used with a bass, really affirming that I need to do this mod, BTW), and, though I was already aware of this before getting the pedal, the range of the sweep kinda... sucks. How can I extend it while keeping the same basic tone? Cause I really like the tone (If it didn't cut so much low end), but I really have to move it to make any difference in my sound.
Quote by C0_0kie
guitar solo - "meh, every song got one"
bass solo - "OMGZ0R U IS PRO MENZ"


Quote by lucertia.
fapfapfapfapfapfap


burgerburgerburgerburger


Quote by DeAd-RiP
Sir I would like to sex your bass.
#24
Quote by kugelspot
The pedal came in the mail a couple days ago. I've been fooling around with it (it's hard to not make it sound like ass when used with a bass, really affirming that I need to do this mod, BTW), and, though I was already aware of this before getting the pedal, the range of the sweep kinda... sucks. How can I extend it while keeping the same basic tone? Cause I really like the tone (If it didn't cut so much low end), but I really have to move it to make any difference in my sound.


Do the mod. See what happens then.

I dont think you can add much sweep unless you wanna rebuild the whole thing.
#25
Quote by Final !mpact
I dont think you can add much sweep unless you wanna rebuild the whole thing.


Is that because of the no-pots-light-sensing-thing? I was afraid of that
Quote by C0_0kie
guitar solo - "meh, every song got one"
bass solo - "OMGZ0R U IS PRO MENZ"


Quote by lucertia.
fapfapfapfapfapfap


burgerburgerburgerburger


Quote by DeAd-RiP
Sir I would like to sex your bass.
#26
Quote by Invader Jim
Basses put out a higher voltage than guitars. A guitar's amplitude peaks at about 100mV. Basses, if I remember correctly, peak at about 500mV-1V.

The reason some pedals (even guitar amps) can't be used for basses is because the higher amplitude can over-load the pedal/guitar amp. Some pedals, however, can safely be used with a bass (flangers and wahs are the only ones I know of).

For your first project, you could get a Crybaby Original and replace the sweep cap with a .068-ish cap. Viola! You now have a Crybaby Bass Wah. That's the only difference between the Originals and Bass Wahs, btw. So doing this saves you a big chunk of money.

Seriously? then what about super-high power (X2n, Invader, etc) pickups? shouldn't they put out a ton of power? I think the X2n puts out around 500mV. I don't know about the Invader and similar though.
Current Gear:
LTD MH-400 with Gotoh GE1996T (EMG 85/60)
PRS SE Custom 24 (Suhr SSH+/SSV)
Ibanez RG3120 Prestige (Dimarzio Titans)
Squier Vintage Modified 70s Jazz V
Audient iD22 interface
Peavey Revalver 4, UAD Friedman BE100/DS40
Adam S3A monitors
Quote by Anonden
You CAN play anything with anything....but some guitars sound right for some things, and not for others. Single coils sound retarded for metal, though those who are apeshit about harpsichord probably beg to differ.
#28
^ and thats relevent how?
Quote by C0_0kie
guitar solo - "meh, every song got one"
bass solo - "OMGZ0R U IS PRO MENZ"


Quote by lucertia.
fapfapfapfapfapfap


burgerburgerburgerburger


Quote by DeAd-RiP
Sir I would like to sex your bass.
#30
Two things.

1) To get that crybaby sounding good all you need to do is put in that .068uf cap. That's really it.

2) Basses don't always put out more SIGNAL/VOLTAGE than your average guitar. Most passive bass pickups are of the same output as a passive guitar pickups. Most active bass pickups are of the same output as an active guitar pickup.

That being said, most effects will work regardless of signal level, but depending on the effect, there is always a way to deal with that if it becomes a problem. Op-Amp based overdrives and distortions can be modified to have less gain thru adjusting a feedback resistor. Transistor based effects (fuzzes, boosters, and this also works for most compressors, even those which are based on opamps), are even simpler. A simple input trimpot should allow you to control the signal level going into those pedals, (this works best with pedals that are already sensitive to a volume knob adjustment).
Fender MIM Stratocaster
Ibanez TS-9 Tube Screamer
Fulltone OCD
Dallas-Arbiter Wah Baby
Home-Built Germanium Fuzz Face
MXR Carbon Copy Analog Delay
2 Fender Blues Juniors
Last edited by SRVStrat808 at Sep 17, 2008,