.15uf caps instead of .1uf?

Started by Hupla, August 31, 2009, 09:07:37 AM

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Hupla

Ok so I've been gathering parts to mod my DS-1 and over the last month I've been waiting for the place I ordered from to get .1uf caps in and they still aren't in.
Anyway, They offered me .15uf caps instead and I'm wondering will this make a huge difference?

Im guessing not alot but I just want a second opinion.
Completed builds: BSIAB2
Pedals to build: Dr.Boogey, TS-808

JKowalski

They shouldn't make much of a difference.

Hupla

Hopefully it would be for better not worse ha.
Completed builds: BSIAB2
Pedals to build: Dr.Boogey, TS-808

Hupla

Im just after looking at the schematic and .1uf caps are replacing .047uf caps. They look like they are all input caps to different stages so Im guessing there will be more bass response.
Completed builds: BSIAB2
Pedals to build: Dr.Boogey, TS-808

frequencycentral

If you use two .15uF caps in series that'll give you 0.075uF. Another option.
http://www.frequencycentral.co.uk/

Questo è il fiore del partigiano morto per la libertà!

liquids

and if you use the new .15uF in series with the .047uf in ther, you'll have .1uf, another option!  Or you can paralell the .047 caps with another .047 cap...another .1uF option! 

I'd probably just find a supplier with a consistent stock of this, the cap value I go through the most....

Ahhhhhhhhh too many choices!     :D
Breadboard it!

jrod

Maybe the tolerance is such that the cap is really .1uF?

CynicalMan

Quote from: liquids on August 31, 2009, 01:04:05 PM
and if you use the new .15uF in series with the .047uf in ther, you'll have .1uf, another option!  Or you can paralell the .047 caps with another .047 cap...another .1uF option! 

I'd probably just find a supplier with a consistent stock of this, the cap value I go through the most....

Ahhhhhhhhh too many choices!     :D

ummmm... 0.15u in series with 0.047u is about 0.036u
a .15u in series with a .33u is .103125u

MikeH

In any distortion/od/fuzz/booster you build it won't make any difference at all.  When you get into effects that use LFOs, like tremolos and phasers, or that use clock chips, like flangers, choruses and delays, it will matter but only in certain instances.  And even then it won't matter that much.
"Sounds like a Fab Metal to me." -DougH

BAARON

If the mod in question is the Keeley mod (which I strongly suspect, due to your lust for 0.1µF caps), 0.15µF caps will most likely have no audible difference as compared to the 0.1µF caps, and perhaps even compared to the default caps Boss uses.  If you take a look at the math, the vast majority of the 0.047µF caps that get replaced in Keeley's mod are already allowing the full range of the guitar through, and using the 0.1µF caps just extends the range even farther below the lowest notes of the instrument.

I would suggest that changing C2, C5, C9, C12, C13, and C14 to the values and types detailed in the Keeley mod will have practically no audible effect on the signal, as most of them change the corner frequencies from things like 3.4 Hz to 1.6 Hz, which is about 3 octaves below what the human ear can distinguish as a musical pitch (and 5 octaves lower than your guitar can play)...  Changing C3 to 0.1µF will make a subtle difference (-1.5db on a low E instead of -3db with almost no difference above open G) but the pedal produces so much distortion (and the transistor treble boost before the op-amp mangles your bass response so much) that you might not even notice it anyway.

NOTE: changing C12 to 0.15µF would affect the voicing of the tone control, so don't use a 0.15µF for that.  It will make the "dark" side of the tone knob slightly darker yet.  As it is already a 0.1µF cap in the actual pedal and Keeley is just changing it for their "we upgrade all your caps and resistorz!!!!!!" marketing, it might not even be worth replacing with a slightly fancier type of capacitor.  All you will be changing is the type of the capacitor, and it's just a tone control, so I seriously doubt it would make an audible difference.
B. Aaron Ennis
If somebody makes a mistake, help them understand what went wrong.  Show them how to do it right.  Be helpful.  Don't just say "you're wrong, moron."

liquids

Quote from: MikeH on August 31, 2009, 04:07:32 PM
In any distortion/od/fuzz/booster you build it won't make any difference at all.  When you get into effects that use LFOs, like tremolos and phasers, or that use clock chips, like flangers, choruses and delays, it will matter but only in certain instances.  And even then it won't matter that much.

Baarons information is much more useful, talking about what is happening in a specific circuit.

To those who don't know better, to say changing the input cap never makes any difference in a gain pedal and it only sometimes make a tiny difference in an LFO, etc, is a vast over-generalization. 
Breadboard it!

MikeH

Quote from: liquids on September 01, 2009, 09:26:58 AM
Quote from: MikeH on August 31, 2009, 04:07:32 PM
In any distortion/od/fuzz/booster you build it won't make any difference at all.  When you get into effects that use LFOs, like tremolos and phasers, or that use clock chips, like flangers, choruses and delays, it will matter but only in certain instances.  And even then it won't matter that much.

Baarons information is much more useful, talking about what is happening in a specific circuit.

To those who don't know better, to say changing the input cap never makes any difference in a gain pedal and it only sometimes make a tiny difference in an LFO, etc, is a vast over-generalization. 

Maybe it's just me, but i will never hear any difference between a .1u and a .15u input cap, in any distortion/od etc.
"Sounds like a Fab Metal to me." -DougH

BAARON

Quote from: MikeH on September 02, 2009, 10:40:49 AM
Quote from: liquids on September 01, 2009, 09:26:58 AM
Quote from: MikeH on August 31, 2009, 04:07:32 PM
In any distortion/od/fuzz/booster you build it won't make any difference at all.  When you get into effects that use LFOs, like tremolos and phasers, or that use clock chips, like flangers, choruses and delays, it will matter but only in certain instances.  And even then it won't matter that much.

Baarons information is much more useful, talking about what is happening in a specific circuit.

To those who don't know better, to say changing the input cap never makes any difference in a gain pedal and it only sometimes make a tiny difference in an LFO, etc, is a vast over-generalization. 

Maybe it's just me, but i will never hear any difference between a .1u and a .15u input cap, in any distortion/od etc.

Depends on the context of the cap.  If it's next to a 470k or 1M biasing resistor, the corner frequency is a couple octaves below human hearing and you certainly won't hear a difference.  But keep in mind that increasing or decreasing the cap or resistor in an RC filter by a ratio of 3:2 (i.e., .1 to .15) results in the frequency being shifted by a perfect fifth, so if it were paired with a small resistor (4k7-10k, for example) to form an RC network in the middle of the guitar's range rather than several octaves below it, you could be shifting the corner frequency nearly all the way from the open G to the high E (or vice versa), which could be noticeable.  (Specifically, bass frequencies would be +1.5 db louder with the larger cap.)  Subtle, but probably audible.
B. Aaron Ennis
If somebody makes a mistake, help them understand what went wrong.  Show them how to do it right.  Be helpful.  Don't just say "you're wrong, moron."

Hupla

Thanks to everyone for all the replies.

Quote from: BAARON on September 01, 2009, 01:03:15 AM
If the mod in question is the Keeley mod (which I strongly suspect, due to your lust for 0.1µF caps), 0.15µF caps will most likely have no audible difference as compared to the 0.1µF caps, and perhaps even compared to the default caps Boss uses.  If you take a look at the math, the vast majority of the 0.047µF caps that get replaced in Keeley's mod are already allowing the full range of the guitar through, and using the 0.1µF caps just extends the range even farther below the lowest notes of the instrument.

I would suggest that changing C2, C5, C9, C12, C13, and C14 to the values and types detailed in the Keeley mod will have practically no audible effect on the signal, as most of them change the corner frequencies from things like 3.4 Hz to 1.6 Hz, which is about 3 octaves below what the human ear can distinguish as a musical pitch (and 5 octaves lower than your guitar can play)...  Changing C3 to 0.1µF will make a subtle difference (-1.5db on a low E instead of -3db with almost no difference above open G) but the pedal produces so much distortion (and the transistor treble boost before the op-amp mangles your bass response so much) that you might not even notice it anyway.

NOTE: changing C12 to 0.15µF would affect the voicing of the tone control, so don't use a 0.15µF for that.  It will make the "dark" side of the tone knob slightly darker yet.  As it is already a 0.1µF cap in the actual pedal and Keeley is just changing it for their "we upgrade all your caps and resistorz!!!!!!" marketing, it might not even be worth replacing with a slightly fancier type of capacitor.  All you will be changing is the type of the capacitor, and it's just a tone control, so I seriously doubt it would make an audible difference.

Yeah it is the Keeley mod. Ill keep in mind what you said about the C12 cap. I wouldn't mind trying it out and seeing but it might just be too much hassle.

What do you mean exactly by corner frequencies?
Completed builds: BSIAB2
Pedals to build: Dr.Boogey, TS-808

BAARON

RC filters roll off high frequencies ("low pass") or low frequencies ("high pass") at a rate of -6 db per octave past the corner frequency.  The "corner frequency" itself is calculated from the resistor and capacitor in question (http://www.muzique.com/schem/filter.htm) and is the point at which there is -3 db of attenuation (after which you will experience a full -6 db per octave).

Keep in mind that the corner frequency is not where the filter will Start rolling off frequencies: it's the point where there's already a complete -3 db cut.  The filter will start rolling off frequencies at about a power of 10 away from the corner frequency (high-pass begins rolling off about 10x the corner frequency, low-pass starts rolling off about 1/10 the corner frequency).

Here's a picture so you can see what I mean.
http://www.soundonsound.com/sos/sep99/images/synthfig3b.gif
B. Aaron Ennis
If somebody makes a mistake, help them understand what went wrong.  Show them how to do it right.  Be helpful.  Don't just say "you're wrong, moron."

Hupla

Ok so I finished the mod. Its all working now. The mod does give some really nice fat lead tones but when playing it with power chords for rhythm playing it just sounds too bassy and fuzzy.

So far I cant find any good heavily distorted tones on it. Boosting lead pedal me thinks. lol
Completed builds: BSIAB2
Pedals to build: Dr.Boogey, TS-808