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Tone Pot Capacitors question

#21
Old Garage-Bander said:
+1
If you like the fancy caps that's fine with me.
If you think the fancy caps sound better that's fine with me too.
But if you want to convince me that the fancy caps have "better" tone, you'll need to bring me a lot of data points to back it up.
Click to expand...

Film caps are more predictable than ceramics caps. I have designed and characterized many signal processing circuits with both. If using ceramic caps, you need to be aware of the dielectric grade and voltage rating of the part. Cheaper grade ceramic caps CAN have a wide part to part initial capacitance tolerance and they can also have non linear responses to voltage, meaning their capacitance can change as a function of the applied voltage. I have seen ceramic caps from different manufacturers that are supposed to be equivalent behave differently. The world is a non linear place and ceramic capacitors are not the most linear of devices. In contrast, film caps are more precise. If you are not a circuit designer worried about saving $0.50 per unit sold and you have access to a film cap, use it.

That said, yes tone controls on guitars are crude circuits that operate at low voltages. If your ceramic cap is behaving close to its rated value and the voltage impacts are negligible, you will not notice any difference when you swap it out for an orange drop. But if 100 people swap caps and don't pay attention to the ceramic specification, some percentage of them may get a different frequency response from what is expected. In other words if you care enough about your tone to swap out caps, why not use a film cap?
 
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#24
fermata said:
The Truth about Tone Capacitors | Atlantic Quality Design, Inc. Musical Products
TL;DR "The data and sound clips above show clearly that for tone capacitors of close measured capacitance value there is no difference in tone."
Click to expand...
And what’s the deal with calling them tone capacitors?
It’s not like there is normally more than one cap in there.
We have to call the tone pot a tone pot to differentiate it from the volume pot.
So what’s the deal with tone pots?
They don’t generate tones.
And without the tone pot, they aren’t much good.
Maybe if we just called them the cap people would’t think that a $6 one sounds better than a 10 cent one?;)
 
#25
(It's his video. Speaking of which, Rob, let us know when your passive tone control video is out!)
Click to expand...

Did some more filming today. It's turning into a bit of an epic. Have shot some frequency sweeps etc, but decided to also record some audio comparisons. Should be finished later this week...

As for different "sounding" caps of the same capacitance, well I can't really hear a difference. (FWIW, I'm a pro player, with music degree, lots of studio time blah blah blah, so I like to think I've got good ears I suppose...) But honestly, if you do a mod that makes you feel good about your bass, and makes you want to go and pick it up and play... makes it feel like that bass is a friend, then go for it I reckon. Music is an emotional thing, right? Mojo, relics, patina, old-school, it's all cool stuff. The lighting and decor in a recording studio doesn't effect the recording equipment, but a studio with a cool vibe will pull better sounding takes out of musos...
 
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#26
RobbieK said:
Did some more filming today. It's turning into a bit of an epic. Have shot some frequency sweeps etc, but decided to also record some audio comparisons. Should be finished later this week...

As for different "sounding" caps of the same capacitance, well I can't really hear a difference. (FWIW, I'm a pro player, with music degree, lots of studio time blah blah blah, so I like to think I've got good ears I suppose...) But honestly, if you do a mod that makes you feel good about your bass, and makes you want to go and pick it up and play... makes it feel like that bass is a friend, then go for it I reckon. Music is an emotional thing, right? Mojo, relics, patina, old-school, it's all cool stuff. The lighting and decor in a recording studio doesn't effect the recording equipment, but a studio with a cool vibe will pull better sounding takes out of musos...
Click to expand...

Yep. I've posted many times about choosing caps mainly for their color in some cases (Purple Drops, anyone?), and I wasn't being facetious at all. Recently I've been working a lot with passive tone controls for a customer who mainly builds Jazz Bass variants, looking forward to checking out your new vid.
 
#27
Surely the tone of the capicitance can't be the same for:
polyester, ceramic, paper in oil, Sprague orange drop, Mullard tropical fish, etc.

Oh yes it is; the difference is the value and tolerance of the cap.
Also interested in the video; pretty amazing the differences is design changes of an LCR ciruit for a MI.
 
#29
Ringhammer said:
Can I enterpret this preference (.022 for Jazz / .047 for P-bass) to the fact that there are 2 pickups being controlled by one pot in a Jazz while only one pickup is on the tone pot of a typical P-bass?
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Typically there is only one tone pot so only one tone cap.
It gets difficult to have tone pots that don't interact on a passive bass.
Active could be a different story.
0.47 is typical for a passive bass, regardless of jazz or P. Think about a P/J with just one tone pot.
You can put in whatever size tone cap that pleases you.
The type of pick ups and values of the pots may affect how the tone control works/what value you use.
Nothing wrong with experimenting though.
 
#32
saabfender said:
I’m not a doctor nor do I play one on TV.
Click to expand...
tonedr.jpg
 
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#34
Killed_by_Death said:
The values are generally 0.047 uF (47 nF) & 0.022 uF (22 nF).

I try to avoid using leading decimal points & go with nanoFarads (nF).
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I'm the opposite; two units: pf and uf is good enough for me. If you get too many prefix values involved it becomes more confusing and a greater chance for errors in conversion calculations. Practical unit ranges for me are 1 to 1000pf, .001 uf to 100,000 uf, followed by farads, although these were only a theoretical value until recent times when a 1 farad capacitor became a practical reality.

I only started seeing nanofarads being used in the 1980's.
Millifarads, centifarads, etc. never caught on as practical units. In the old days, pf were referred to as uuf, micro-micro farads.
 
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#36
I only started seeing nanofarads being used in the 1980's.
Click to expand...

Yeah I think that's true. Old valve amp schematics will always have decimal places of micro farads, but modern schematics will usually use nanos.

I think if you are into audio electronics, you just have to get used to all three - picos, nanos, and micros. And get used to swapping between them. It's the way of the world...
 
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#38
Recently put a .1 uF cap in my SCPB to carve out some highs but it seemed to wipe out the mids and the character too so I went back to the .047 uF and decided to let the tone controls on the bass amp do the carving. YMMV
 
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