DIYstompboxes.com

DIY Stompboxes => Building your own stompbox => Topic started by: Aharon on April 07, 2007, 04:13:22 PM

Title: Resistor and cap type,audible diference?
Post by: Aharon on April 07, 2007, 04:13:22 PM
Have you found that using all 1% resistors and "quality" caps makes and audible diference in your projects?
Thanks
Aharon.
Title: Re: Resistor and cap type,audible diference?
Post by: markm on April 07, 2007, 05:08:55 PM
I don't, others do.
Try it!  :)
Title: Re: Resistor and cap type,audible diference?
Post by: JimRayden on April 07, 2007, 06:02:42 PM
Me neither, but I haven't done a proper a/b test yet.

---------
Jimbo
Title: Re: Resistor and cap type,audible diference?
Post by: RaceDriver205 on April 08, 2007, 05:16:18 AM
If you remove the antenna from your car, you'll get better acceleration  ;)
Title: Re: Resistor and cap type,audible diference?
Post by: aron on April 08, 2007, 05:50:37 AM
Do a test with capacitors. First try all of a certain type (ceramics for example), then try all film capacitors and make your own decision. Measure your capacitor values and try and get them as close as possible when doing the test.
Title: Re: Resistor and cap type,audible diference?
Post by: Paul Perry (Frostwave) on April 08, 2007, 09:11:46 AM
If there is a difference, it will depend very much on where the component is, in a particular circuit.
What I mean is, there are certain points in certain circuits where the various imperfections of components - and no component is 'ideal' - may matter.
Title: Re: Resistor and cap type,audible diference?
Post by: MKB on April 08, 2007, 09:45:13 AM
In my experience, the simpler a circuit is, the bigger difference a particular capacitor dielectric or resistor type makes.  One of the things you pay for when you buy a Fulltone or Z. Vex effect is the careful optimization of component types.  In one Fulltone pedal (a well known modification of a Voodoo labs Overdrive pedal), some of the magic is in the use of "lower quality" dielectric ceramic and tantalum signal caps, the same pedal with different part types (i.e. say mylar or polypropylene film) caps in the same locations will sound different, and not as good.  Although changing the part construction is mostly in the last 10% or so of tweaking.  Fuller took a mediocre pedal, tweaked and modified it a bit, and made it exceptional; and part of this magic was good ears working with part types.

So, working with resistor types and capacitor formulations is another parameter you can tweak in order to get the sound you want.  It should not be ignored as it does make a difference.  But "better", i.e. more high tech and expensive, does not necessarily mean better tone.
Title: Re: Resistor and cap type,audible diference?
Post by: R.G. on April 08, 2007, 10:16:45 AM
Also, run - do not walk - away from anyone who is trying to sell you something that sounds magically better because it uses solid-gold/vintage/pure/yada/yada parts.

In my prior job, we referred to this kind of thing as an intelligence test.
Title: Re: Resistor and cap type,audible diference?
Post by: petemoore on April 08, 2007, 12:15:45 PM
  Here's some...application recommendations...
  Before buying expensive fancies for SB usages...
  To sort of illustrate what the order of buying 'fancies' might be
  'excellent' cables for the signal path connections?
  What is the source [quality Magnetic pickup?]?
  ____________
  *except for 'brownie wafer' capacitors...I don't use, and believe the mojo tales on the subject [testing was done]...
  ____________
  It's the entire chain. It is a chain, if it works as a chain.
  how strong is the chain? As strong as the weakest link.
  For 'extreme strength' testing of a link in a chain, every other link must be...extremely strong.
  That said, all the modern board components tested are..very very strong, I can't say the same for cables, I don't know the strength of each link you are using.
 
   
Title: Re: Resistor and cap type,audible diference?
Post by: Aharon on April 08, 2007, 12:25:07 PM
Quote from: R.G. on April 08, 2007, 10:16:45 AM
Also, run - do not walk - away from anyone who is trying to sell you something that sounds magically better because it uses solid-gold/vintage/pure/yada/yada parts.

In my prior job, we referred to this kind of thing as an intelligence test.


I'm aware of that but I was talking more like plate resistors in tube amps where carbon comps are noisier than metal or 1/2 watts having more residual (shot?)noise than 1W.........along those lines,not audiofool crap,I'm talking stuff that you can actually measure.
Title: Re: Resistor and cap type,audible diference?
Post by: mac on April 08, 2007, 01:04:42 PM
Talking about pedals, I can't find any difference between std resistors and metal films, ie, rangemaster. But I hear differences between ceramic, poly and electro caps; but some say this could be because of the deviation from the supposed value. I do not have a capacitor tester, but in every project I breadboard it is always the same tonal change... :icon_exclaim:

mac
Title: Re: Resistor and cap type,audible diference?
Post by: dxm1 on April 08, 2007, 01:29:24 PM
I don't know why, but I have found that using polystyrene caps for the 470pF C5 in the BSIAB2 _does_ make an audible difference. I've made about a half dozen of these as gifts for friends, and all agree that at gig volumes, units with these caps sound "better". I can't hear the difference at bench levels, but I trust the ears of others. So far, everyone has returned their unit for this "upgrade". Foolish mojo? I dunno...
Title: Re: Resistor and cap type,audible diference?
Post by: mac on April 08, 2007, 03:46:02 PM
I hear the difference at room levels.

If you breadboard a fuzz face with a 2.2uf poly, ceramics, tantalum and electro, and put a switch to quickly swap the caps you'll hear how different they sound even with a ss amp at low volumes.  A good amp will make it more noticeable.
Sometime ago, to be sure that I was not sensing deviations due to tolerance, I put a 2.2uf poly and bought a dozen of 2.2uf electros and even 3.3uf and 1uf, just to statistically compensate. Even the 3.3uf nor 2 or 3 parallel 1uf sounded as good as the poly. My mother who is 74, supposidly some ear loss, could hear the difference as well. She does not like electros... and if "la mamma" says so, it's ok for me  :icon_mrgreen:

mac
Title: Re: Resistor and cap type,audible diference?
Post by: R.G. on April 08, 2007, 03:51:29 PM
Remember that electros may have tolerances of +80%, -20%. You really can't flip electros in and expect them to statistically average.

You simply must measure the capacitances and do a blind test to see if you can even guess when the capacitors have changed, let alone which is better at a rate better than random guessing. Humans are BAD at being impartial, even with themselves.
Title: Re: Resistor and cap type,audible diference?
Post by: mac on April 09, 2007, 01:54:56 PM
QuoteRemember that electros may have tolerances of +80%, -20%. You really can't flip electros in and expect them to statistically average.
You simply must measure the capacitances and do a blind test to see if you can even guess when the capacitors have changed, let alone which is better at a rate better than random guessing. Humans are BAD at being impartial, even with themselves.

Yes, I'm aware of all that, that's why I tried with different 3.3uf. In the absence of a cap meter it may give a hint. I should have said "statistically".  :icon_redface:
And more, sometimes one can have some prejudice about electros that can make ourselves be certain that they are terrible caps. And I guess that this is my case. Guilty as charged. Electros suffer from aging, bad high frew response...
The best way to do a test is like you said, measuring the caps. And let someone change the caps while you're playing. And do not spend a lot of time to decide because of ear fatigue.
And who made the cap also matters.

How can I explain it better? A +/-100% tolerance of an electro will cause some increase/reduction in the bass response, always talking about the FF input cap. This will be the main effect. What I'm trying to describe is a change in the fuzziness at high drive levels. IMHO the polys makes the signal more crystal, more alive. Hard to find the words in english.

Anyway i'm going to buy a a cap meter...  :icon_mrgreen:

*****************

I've been reading  about caps, mainly dielectric properties and which cap fits in some projects and which not. But no one related to stompboxes and distorting a signal like we do.

RG, does the dielectric may/may not alter the signal to audible levels? What can you say about different dielectrics?
Is it possibly that when the voltage changes so fast, the induced polaritazion in the dielectric could react slow enough to be audible?

mac
Title: Re: Resistor and cap type,audible diference?
Post by: Gus on April 09, 2007, 03:00:57 PM
Do what Aron posted and if you can record the results.

  Name the tracks something other than a,b,1,2,3 etc things like tree, cat, dog.  letters or numbers seem to "want" to be put in order IMO.

Let them sit a few days and let someone hear them (don't tell them what the test is about) and give their feedback

Caps are cheap.  Make up your own mind.

There is Physics behind some of the sound.

Go to the sencore site and download the PDF for the LC103 meter read the ceramic test section.

Some of us have been posting about caps in effects for years old ampage days.
Title: Re: Resistor and cap type,audible diference?
Post by: BMF Effects on April 09, 2007, 03:18:01 PM
Resistors - One day I built three Red Llamas. One with carbon films, one with carbon comps and one with metal films. All resistors were measured within 2% of the required value. I could not hear an appreciable difference between the three in either tone or noise. I also built two LPB-1's, one with carbon comps and one with metal films. There's was a touch (almost imperceptible) more clarity and less noise in the metal film loaded one.

Capacitors - I prefer the brown Panasonic ECQ-B series caps over the Xicon/green chiclet ones. I think they sound a little warmer. I could also be hearing what I want to hear.

Electrolytics - Never compared brands so I can't comment. It never occurred to me to try. Electrolytics are electrolytics if you ask me.
Title: Re: Resistor and cap type,audible diference?
Post by: RaceDriver205 on April 09, 2007, 08:01:20 PM
Im sorry, Im holding this capacitor up to my ear and I can't hear anything  ???
Title: Re: Resistor and cap type,audible diference?
Post by: shadowmaster on April 10, 2007, 07:36:21 AM
Eric Johnson can determine what type of battery is in his overdrive pedal just by the sound of it.
Title: Re: Resistor and cap type,audible diference?
Post by: BMF Effects on April 10, 2007, 08:18:53 AM
Quote from: RaceDriver205 on April 09, 2007, 08:01:20 PM
Im sorry, Im holding this capacitor up to my ear and I can't hear anything  ???

Did you try the other ear?  :icon_mrgreen:
Title: Re: Resistor and cap type,audible diference?
Post by: R.G. on April 10, 2007, 08:29:45 AM
QuoteEric Johnson can determine what type of battery is in his overdrive pedal just by the sound of it.
... or so he says...  ;)

I've learned it's not smart to bet either that someone can or can't do something until you have a lot more info about it.  Uri Geller can bend spoons, too.
Title: Re: Resistor and cap type,audible diference?
Post by: MKB on April 10, 2007, 09:03:59 AM
I can clearly hear the difference with some Duracell 9V's and other brands in my wireless monitor pack; you get a Duracell every now and then that dies after 5 minutes of use instead of several hours.  Makes everything get quiet fast, and the first set sucks... 8)

Eric Johnson also claims he has to remove the bottom plate screw in his Fuzz Face and hold it on with a rubber band in order for it to sound right.  I could buy the battery claim a lot easier than the bottom plate screw claim.  Batteries have internal impedances that vary according to discharge level, at leat there is some sort of explanation for that.
Title: Re: Resistor and cap type,audible diference?
Post by: Mark Hammer on April 10, 2007, 10:13:31 AM
1)  What gets reported as some recording artist's preference and basis for preference is not always guaranteed to be a 100% accurate reflection of reality.  The aforementioned capability to detect battery differences likely refers to aging batteries, and the "screw thing" may well have something to do with keeping some things from contacting other things in a pinch.  Of course, maybe Keith Richards really DID snort his dad's ashes with cocaine.....

2) The qualifier of biased perception and the need for blind A/B testing is something that still needs emphasizing.  I point that out not to undermine the claims of those who "hear things" with component-type differences, but rather to be able to depend on, and use, the observations made.  Sometimes, component-type changes DO make a difference, and many times they don't.  For my part, it is just as much waste to dismiss any claims as preposterous with a wave of the hand as it it would be to accept them all.  Rigorous comparison is what lets you separate the wheat from the chaff.  Even that, in itself, is not the true goal.  The reason one needs to nail down when heard differences truly emerge from component type and not from component tolerances or bias or poor testing conditions is because it allows you to know what matters and why, and that is what lets you improve other things based on sound theory.  Which leads us to...

3) We get into this debate intermittently, and rarely does the qualifier of where get brought into the discussion.  Would I expect metal film resistors to have some impact on sonic quality if they were used in the voltage divider that supplies the Vref?  Not much, and certainly MUCH less than if we were talking about the input resistor to an op-amp set for a gain of 200.  Would I expect the type of capacitor used to set the gain of a transistor via the emitter-ground path to be as influential as a cap directly in the signal path?  Not really.  Both of those proclamations may well be naive on my part, but the fact remains that whenever we discuss component type/composition, we are broaching the potential for sonic differences, and nothing more.  What has to be asked is "What sort of potential change at this point in the circuit would a change in these component parameters potentially have?".  Until that question gets addressed, it's all just voodoo handwaving, and our component claims are simply hierophanies.
Title: Re: Resistor and cap type,audible diference?
Post by: dirk on April 10, 2007, 11:57:50 AM
Carbon resistors change their resistance according to the voltage across it. You need a big voltage change to get a relatively small resistance change. So basically the only sane use, (add harmonics other than just noise) for a carbon resistor, is to use it with a tube as an anode load resistor.
Title: Re: Resistor and cap type,audible diference?
Post by: R.G. on April 10, 2007, 12:54:50 PM
Correct, Dirk.

See "Use of Carbon Comp Resistors for Magic Mojo",  22 March 2002, at GEO, http://www.geofex.com (http://www.geofex.com).
Title: Re: Resistor and cap type,audible diference?
Post by: analogmike on April 10, 2007, 01:38:50 PM
Quote from: BMF Effects on April 09, 2007, 03:18:01 PM

Electrolytics - Never compared brands so I can't comment. It never occurred to me to try. Electrolytics are electrolytics if you ask me.

Some are much better than others. I can hear the difference between 2 different models of 1uF caps of the same brand in our chorus pedal. Try to use the low inductance type for signal coupling caps or they can color your tone a bit (sometimes good, sometimes not). But we use the cheap big blue xicon in most places and find they sound awesome.

have fun!
Title: Re: Resistor and cap type,audible diference?
Post by: mac on April 10, 2007, 02:10:31 PM
... As my father used to say, "I don't believe in witches, but I married one!"  :icon_mrgreen:
Title: Re: Resistor and cap type,audible diference?
Post by: BMF Effects on April 10, 2007, 02:38:42 PM
Quote from: analogmike on April 10, 2007, 01:38:50 PM
Quote from: BMF Effects on April 09, 2007, 03:18:01 PM

Electrolytics - Never compared brands so I can't comment. It never occurred to me to try. Electrolytics are electrolytics if you ask me.

Some are much better than others. I can hear the difference between 2 different models of 1uF caps of the same brand in our chorus pedal. Try to use the low inductance type for signal coupling caps or they can color your tone a bit (sometimes good, sometimes not). But we use the cheap big blue xicon in most places and find they sound awesome.

have fun!

Re-reading that, I think I might have come across like a putz which was not my intention. Thanks to Mike for the schooling, I'll have to give it a try.
Title: Re: Resistor and cap type,audible diference?
Post by: RaceDriver205 on April 10, 2007, 07:27:11 PM
QuoteEric Johnson also claims he has to remove the bottom plate screw in his Fuzz Face and hold it on with a rubber band in order for it to sound right.
What a loon! Maybe when all you do all day since you were a kid is play guitar, it gets to you! :D
Title: Re: Resistor and cap type,audible diference?
Post by: STOMPmole on April 10, 2007, 08:51:27 PM
Quote from: shadowmaster on April 10, 2007, 07:36:21 AM
Eric Johnson can determine what type of battery is in his overdrive pedal just by the sound of it.

Too bad he couldn't hear that the tone of his last record sounded like it was recorded under a blanket.  ;D

I think that caps make a difference depending on their location in the circuit (and the complexity of it) as does resistor type...but that's just my personal opinion based on my own limited and biased observations.