Capacitor replacement in passive basses

[Muppet]

The 'web is full of stuff about using orange drop caps or traditional paper in oil rather than the ones that come as standard in, say, Fenders.

Has anyone spent any time swapping tone capacitors out for replacements and has it really made any noticeable difference at all to tone?

cheers

Steve

[Grangur]

I once put a switch on a bass to switch between 0.1 and 0.047 capacitors. Both were orange drop caps. I didn't notice any real difference between the 2.
As I understand it, the difference will mainly be in the amount you need to turn the pot to achieve a reduction in the treble with the filtering.

I guess if you were to attach an oscilloscope to the circuit, the difference in the waveform may be considerable, but IMHO, it's not a biggie.

That said, I mostly keep the tone wound right open. So if I built a bass I possibly wouldn't have a tone control at all. So maybe I'm not the person to ask.

[4stringslow]

Interesting question. I've never tried it but I wouldn't expect changing the type of capacitor to a make a difference if both type have the same actual capacitance value.

The passive tone control is a simple one-pole filter and as far as the design of it's characteristics is concerned it is the value of the capacitor (and the resistor) that is used to calculate this. The type of capacitor is not factored into the design calculation.

Because of this, I suspect this sort of thing strays into the area of 'golden ears' and the placebo effect.

[rmorris]

worth a read through...


[url="http://www.gibson.com/News-Lifestyle/Features/en-us/Orange-Drops-Busting-Tone-Control-Capacitor-Myths.aspx"]http://www.gibson.com/News-Lifestyle/Features/en-us/Orange-Drops-Busting-Tone-Control-Capacitor-Myths.aspx[/url]

[4stringslow]

Good article. The point about different capacitor types having different value tolerances is a good one. I stand by my previous comment that different capacitor types will make no difference providing their values are the same but of course if a particular capacitor type has a very wide tolerance (and up to 80% is not uncommon for some types) then a replacement with nominally the same value might in fact have a very different value, which might well have an effect on the tone. But this effect would not be a result of the type of capacitor, only because of the different value.

Likewise, different capacitor types have different temperature characteristics causing their value to change under different conditions. Again, this could theoretically give rise to tone changes but would a result of the value changes rather than the actual type per se.

So, by all means experiment with different capacitors to get the tone you like best, but be careful when drawing conclusions about what is creating that tone - at least not without a lot of fancy test equipment that can properly analyse what's going on in the overall circuit.

[Muppet]

I'm only using my ears rather than fancy equipment but I tried this last night. I used a 0.047uf PIO against the stock ceramic disc 0.05 and I'm buggered if I can tell any difference once you bring leads and amps and stuff in to the equation!

[Hobbayne]

Limelight use a [size=4][font=arial,helvetica,sans-serif]Sprague cap in their vintage relic basses. I personally havent noticed much difference soundwise. [size=4][font=arial,helvetica,sans-serif] [/font][/size][/font][/size]
https://www.talkbass.com/threads/sprague-orange-drop-capacitors-worth-it.465558/

[blisters on my fingers]

From Gibson [url="http://store.gibson.com/historic-spec-bumble-bee-capacitors-two-pack/"]http://store.gibson....itors-two-pack [/url]a mere $129.99 !!

From Strings Direct [url="http://www.stringsdirect.co.uk/parts-c4/potentiometers-c109/gibson-gibson-historic-bumble-bee-capacitors-2-pack-p5287"]http://www.stringsdi...rs-2-pack-p5287 [/url]a bargain £64.99 including free delivery. Wow... we have it made over here

What you are actually getting for your money [url="http://www.mylespaul.com/forums/historics-reissues/118027-historic-gibson-faux-bumblebee-caps.html"]http://www.mylespaul...lebee-caps.html[/url]

This thread was "old news" in 2010 but still rumbling (bumbling)? on four years later.

A selection of different value caps, some wire and a couple of alligator clips will cost next to nothing, and there are Youtube videos showing just how easy it is to try it. Could well be worth a couple of hours experimenting and improving your sound to your satisfaction

Of course the obligatory smoke and mirrors, snake oil and bollocks will cost, after all that's what Mojo is all about

All I get from the mylespaul thread is the value of the capacitor affects the tone control to a greater or lesser degree. Try a few out, pick the one you think sounds the best

That's it ?

[rmorris]

[quote name='4stringslow' timestamp='1468226689' post='3089298']
Good article. The point about different capacitor types having different value tolerances is a good one. I stand by my previous comment that different capacitor types will make no difference providing their values are the same but of course if a particular capacitor type has a very wide tolerance (and up to 80% is not uncommon for some types) then a replacement with nominally the same value might in fact have a very different value, which might well have an effect on the tone. But this effect would not be a result of the type of capacitor, only because of the different value.

Likewise, different capacitor types have different temperature characteristics causing their value to change under different conditions. Again, this could theoretically give rise to tone changes but would a result of the value changes rather than the actual type per se.

So, by all means experiment with different capacitors to get the tone you like best, but be careful when drawing conclusions about what is creating that tone - at least not without a lot of fancy test equipment that can properly analyse what's going on in the overall circuit.
[/quote]

Yes - it's sort of obvious to avoid wide tolerance caps.
Apart from temperature dependencies, different types of capacitor dielectric have different voltage coefficients.
ie the actual capacitance value varies with the voltage across the cap. Since an audio signal is, by definition, constantly changing this has an effect on the signal and gives rise to harmonics not in the original signal - ie distortion.
But to put this into perspective it's a relatively tiny effect in the context of a bass or guitar.
From past experience it might add a dB of distortion to a high quality audio signal eg 89dB cf 90dB.
So it seems technically interesting but not a real issue for a passive tone control.

[ahpook]

You need to be fitting condensors, not capacitors if you're after [i]real[/i] vintage tone.

[rmorris]

[quote name='ahpook' timestamp='1468411404' post='3090739']
You need to be fitting condensors, not capacitors if you're after [i]real[/i] vintage tone.


[/quote]

yeah - with 'authentic vintage analogue dielectric'

[Zombie1965]

The type of cap will make a very small difference in your tone, hardly noticeable. The value you chose will determine how much high end is preserved and how much difference there is between fully open and fully closed.

Orange drops are used plentifully because they are a good fit size wise in the control cavity, reliable and cost effective.

Pio caps can sound a tiny bit better, but they also dry out and age over time, changing the tone as they do so, have a much shorter lifespan. And they are much more expensive.

[ahpook]

[quote name='rmorris' timestamp='1468413136' post='3090757']
yeah - with 'authentic vintage analogue dielectric'
[/quote]

I think it all went downhill after they stopped fitting Leyden jars....

[4stringslow]

[discreet]

Got an orange Sprague Pacer 0.1uF cap in my Road Worn Precision, it has definitely made [i]some [/i]difference. Which you really only hear as you roll off the tone control, i.e. it seems to cut more treble so you get a slightly more vintage, velvety tone than the stock cap. It has a different value than the original.

Edited July 13, 2016 by discreet

[Muppet]

[quote name='discreet' timestamp='1468448040' post='3091068']
Got an orange Sprague Pacer 0.1uF cap in my Road Worn Precision, it has definitely made [i]some [/i]difference. Which you really only hear as you roll off the tone control, i.e. it seems to cut more treble so you get a slightly more vintage, velvety tone than the stock cap. It has a different value than the original.
[/quote]

That's interesting! Did you choose this value and type to intentionally to get this more vintage tone or was it for some other reason?

I ask because I'd like to be able to say caps of a certain value and type have certain properties. Sure I could audition loads to find the one that sounded right (and really I should do that) but I may never get there...

Steve

[4stringslow]

Is the tone control on the bass really that important in these days of amps with multi-band tone controls?

Why roll off anything within the bass when it can be done within the amp, and with a great deal more control?

[rmorris]

[quote name='4stringslow' timestamp='1468482860' post='3091161']
Is the tone control on the bass really that important in these days of amps with multi-band tone controls?

Why roll off anything within the bass when it can be done within the amp, and with a great deal more control?
[/quote]

+1

I used to have a fretless Westone Thunder which did benefit from knocking off treble clank but apart from that little use of passive tone knob.

[Oopsdabassist]

I tend to adjust my tone 'on the fly' dependant on song requirements using the bass tone knob. Adjustments at the amp are done at setup for a gig to get the sound for the room.

Whatever the caps are that KiOgon uses on his looms, they are fine by me, installed one of his looms in my P at the weekend and it sings to me now!!

[discreet]

[quote name='Muppet' timestamp='1468479190' post='3091137']
That's interesting! Did you choose this value and type to intentionally to get this more vintage tone or was it for some other reason?
[/quote]

I was having the electrics replaced because of a dodgy volume pot and John recommended the Sprague Pacer, which works very well. I wouldn't say it's necessarily better than the stock cap, but it IS different. I take the points about doing all your EQ work from the amp, but it is useful to have a fundamental tone option at your fingertips which can be very quickly changed between songs and even during songs.

When I had an active it was convenient to have EQ options on the bass, but I don't like actives, so the passive treble-cut is what you get!

[bobbass4k]

As that Gibson article says, the majority of any perceived differences can probably be attributed to tolerance/temperature response differences, an old cheap ceramic with a -20/+80% tolerance could easily be twice it's supposed value, and over twice the actual value of another identical one.

With PIO specifically, I believe they were commonly used in the "vintage (60's/70's)" era because they were the best high voltage option available at the time and so were used in amplifiers, and so they put them in tone sections of guitars/basses because it's just what they had around. Like most of these things, the motivations at the time were nothing to do with tonal quality and everything to do with expediency/cost...

[discreet]

Well there you go. It's basically another subject in a long list of subjects that we get bogged down in, rather than simply play our basses.

[4stringslow]

[quote name='discreet' timestamp='1468495749' post='3091301']
I take the points about doing all your EQ work from the amp, but it is useful to have a fundamental tone option at your fingertips which can be very quickly changed between songs and even during songs.
[/quote]

Fair point.

[FinnDave]

Our guitarist often tries to persuade me that I must change the capacitors in my basses 'to let the tone out'. I always play with tone and volume control on the bass fully open, so surely I am by-passing the cap anyway?

He also believes that guitars and basses sound 'better' with the on board volume turned down to about half way, so I take these ides with a pinch of salt. Don't get me wrong, great guy, just got one or two odd ideas!

[NancyJohnson]

[quote name='FinnDave' timestamp='1473580477' post='3131269']
Our guitarist often tries to persuade me that I must change the capacitors in my basses 'to let the tone out'. I always play with tone and volume control on the bass fully open, so surely I am by-passing the cap anyway?

He also believes that guitars and basses sound 'better' with the on board volume turned down to about half way, so I take these ides with a pinch of salt. Don't get me wrong, great guy, just got one or two odd ideas!
[/quote]

I'm 100% with you on the first point. My old Precision went through various wiring configurations, one time the pickup was just wired into the volume pot, on another straight into the jack socket.

On point #2, concur. What is all this turning down malarkey about? Are we not men? Heh.