Jump to content
Why become a member? ×

Capacitors, ceramic or poly?


Recommended Posts

[quote name='Dom in Somerset' post='898088' date='Jul 18 2010, 02:50 PM']I'm about to order the electrics for my latest project, I know nothing about the subject, happy to follow a wiring diagram.
CH guitars do wiring kits for certain basses and guitars, they do two for Jazz bass, one with a ceramic capacitor one with poly- what difference does it make (if any?)[/quote]


Let me know how you get on, I am going to have a go with this in a few weeks!

Link to comment
Share on other sites

Ceramic are you traditional guitar type. I don't know which "poly" ones they are referring to but....
Polyester caps are general, all purpose cheap jobs.
Polystyrene are very accurate caps used in test equipment etc.. susceptible to solvents etc.
Polypropylene are caps best suited to high quality audio applications.
Polycarbonate again good for audio and have good temperature handling qualities.

Edited by Ou7shined
Link to comment
Share on other sites

I would definitely not go with ceramic. Polyester film (which is what these likely are) may be relatively inexpensive but they're also good for audio, and are the ones most commonly used in decent quality audio circuits along with polystyrene, polypropylene, and metallised polyester.

Link to comment
Share on other sites

Ceramic capacitors are designed to be used for supply decoupling, where you want to remove any high frequency noise on a supply line, they were never designed to pass quality audio. The best choice for audio is polypropylene, you will get most values you need for guitar use in a polyprop capacitor.

Link to comment
Share on other sites

Isn't someone going to say 'if you want it to sound like a Jazz bass you'll need to use similar components and so use ceramic'?

The OP has a good question, like you I know nothing about this sort of thing. How about asking the supplier people to see why they offer the choice and what they recommend for your use?

Capacitors are certainly important to hi-fi enthusiasts, how important they are for guitars, others are already advising.

Link to comment
Share on other sites

How many people crank down the tone control (passive bass) to remove some of the top end? That's all the cap will do, there's subtle frequency response differences in different manufacture method caps, that you can detect with an oscilloscope but I'll be darned if I can hear any difference when I'm bashing out Jam numbers in a pub gig.

There, I've said it. 90% baloney spoken about the benefits of sprague orange drop caps and overpriced nos components. All you're doing is cutting out a bit of the treble.

[ducks for cover]

Link to comment
Share on other sites

[quote name='BanditSid' post='898336' date='Jul 18 2010, 08:00 PM']Ceramic capacitors are designed to be used for supply decoupling, where you want to remove any high frequency noise on a supply line, they were never designed to pass quality audio. The best choice for audio is polypropylene, you will get most values you need for guitar use in a polyprop capacitor.[/quote]

What a load of crap.

Either will be fine.

Link to comment
Share on other sites

Basschat is great in that it caters well for both sets of demographic; those that think it doesn't make a difference and those that do.
Most of the latter school speak sense from the theoretical point of view, now the real issue is one of [i]significance[/i]. Does it make a significant difference to the human ear.
Be interested to hear your field test.

I spent an afternoon once fitting a P-bass with a 3-way switch that brought in a range of different value (and type) caps on my tone knob.
I found no difference whatsoever (in my ears) to the tonal quality as I backed off the treble - it all sounded muddy once it got past 1/2 way. In theory it should have changed the amount of treble cut-off as well as influencing the ramp of the pot, but I'm pretty sure you'd only really see this with an oscilloscope or spectrum analyser. It all sounded really mushy so I went back to playing my EBMM Stingray. :)

Link to comment
Share on other sites

Just changed the stock Jap ceramic for a high voltage Sprague Orange Drop poly and wow, the poly one is so much bigger. And orangeyer.

Early Gibsons and Fenders (50s - 60s) used 400v caps as they were left over from amp builds. Apparantly.

Edited by johnnylager
Link to comment
Share on other sites

[quote name='Al Heeley' post='902935' date='Jul 23 2010, 10:46 AM']Basschat is great in that it caters well for both sets of demographic; those that think it doesn't make a difference and those that do.
Most of the latter school speak sense from the theoretical point of view, now the real issue is one of [i]significance[/i]. Does it make a significant difference to the human ear.[/quote]
Well, in [i]theory[/i], a ceramic cap approximates a near perfect form of capacitance, having almost no inductance and a low ESR. In practice, however, you would be hard pressed to find any low-mid to high end audio equipment, professional or otherwise, that uses them regularly in the audio signal path -- and even then, in the case of older equipment, they will often be C0G or NP0 (high stability, generally 1% tolerance).

Now, I'm the last person who's going to say you need a particular brand of capacitor to sound a certain way (12 quid for a paper in oil? hmm maybe not...) but in my experience, working on and listening to audio equipment, if it were me I would choose not to have ceramics in the signal path. There are simply better sounding alternatives. The only reason they were likely used in the original basses and guitars is because they are, in fact, so cheap.

Having said that, I am a man of science, and without having done my own measurements am somewhat uncomfortable with the idea that any benefits could merely be merely psychological. Just because an entire industry is behind an idea, doesn't mean it's true -- just look at the fallacy that is "breaking in" speakers, not to mention the new "neo tone". :rolleyes: I want to believe there's no difference with caps, but I keep hearing one. *shrug* :)

Link to comment
Share on other sites

I'll go along with escholl with 2 comments. If you've ever heard a Fender Telecaster, Fender-Rhodes piano, even a Fender Precision bass guitar ('course you have!), you'll come to the conclusion the designer/champion behind these instruments was a genius and knew a bit about sound. If he wanted to cut treble and a ceramic cap did it in the wrong way then I'm convinced he'd have used something else.

I suppose someone might be able to tell the sonic difference, if there is one, but would it actually be better?

Secondly, I have no experience from which to pull, but I thought the breaking in of speakers was to make allowances in performance expectation for the improvement in suppleness of the suspension, settling of the cone etc. The Barefaced man appears to believe speakers improve significantly after some use, he appears to know a bit too and is likely to have had the opportunity for that experience. It's also said that amps improve as they warm up, my Audiolab hifi amp definitely does so, definitely warmer, deeper bass. Can't explain it though.

Link to comment
Share on other sites

[quote name='escholl' post='903237' date='Jul 23 2010, 02:31 PM']Having said that, I am a man of science, and without having done my own measurements am somewhat uncomfortable with the idea that any benefits could merely be merely psychological. Just because an entire industry is behind an idea, doesn't mean it's true -- just look at the fallacy that is "breaking in" speakers[/quote]

Not wishing to derail this thread but speaker break-in is very real and easily measurable. I've experienced it, in VERY obvious fashion, with a Deltalite 2510 II. Note that Eminence (and other manufacturers) specify their speakers after 'conditioning' to account for this phenomenon. Makes me wonder about judging pristine new cabs in shops.

Re caps, I seriously doubt I could hear/care about the difference, but would be interested to A/B and see!

Link to comment
Share on other sites

I took a Naim pre-amp (an old third-hand 80s one guys, I'm not made of money :) ) in for repair and they replaced some of the capacitors with Tantalum ones. What are the benefits of using Tantalum? I've done the obligatory look-up and see how they get them to work by sintering powder of different grades, just curious as to their properties compared with other capacitor types.

Link to comment
Share on other sites

[quote name='LawrenceH' post='908052' date='Jul 28 2010, 12:00 PM']Not wishing to derail this thread but speaker break-in is very real and easily measurable.[/quote]
This, of course, depends on how you define speaker break-in.

Link to comment
Share on other sites

[quote name='ShergoldSnickers' post='908173' date='Jul 28 2010, 01:36 PM']I took a Naim pre-amp (an old third-hand 80s one guys, I'm not made of money :) ) in for repair and they replaced some of the capacitors with Tantalum ones. What are the benefits of using Tantalum? I've done the obligatory look-up and see how they get them to work by sintering powder of different grades, just curious as to their properties compared with other capacitor types.[/quote]
Tant caps have high tolerance (accurate value) and are (mostly) polar so cannot always be used to replace standard non-polar types. They can blow quite easily of you get them too hot whilst soldering or if you have the polarity the wrong way round.
Cheap ceramic caps can be +/- 10% of the printed value, which tbh makes little diff on a bass guitar tone pot.

[url="http://www.engineersedge.com/instrumentation/tantalum_capacitors.htm"]http://www.engineersedge.com/instrumentati..._capacitors.htm[/url]
Fascinating stuff indeed.

Edited by Al Heeley
Link to comment
Share on other sites

[quote name='4 Strings' post='907944' date='Jul 28 2010, 10:44 AM']I'll go along with escholl with 2 comments. If you've ever heard a Fender Telecaster, Fender-Rhodes piano, even a Fender Precision bass guitar ('course you have!), you'll come to the conclusion the designer/champion behind these instruments was a genius and knew a bit about sound. If he wanted to cut treble and a ceramic cap did it in the wrong way then I'm convinced he'd have used something else.

I suppose someone might be able to tell the sonic difference, if there is one, but would it actually be better?[/quote]
I don't know what the state of capacitor technology was in the 50's, but ceramic may have been his only viable choice at the time in terms of cost/performance, a tradition which likely carried on due to the very low-cost of ceramic caps. There is an interesting article [url="http://www.skguitar.com/SKGS/sk/CapTest/CapTest.htm"]here [/url]which seems to come to the conclusion the difference is present, but likely negligible. Personally, I would choose polyester/polypropylene, but that is likely just my prejudice from years of working with audio equipment.

[quote name='4 Strings' post='907944' date='Jul 28 2010, 10:44 AM']It's also said that amps improve as they warm up, my Audiolab hifi amp definitely does so, definitely warmer, deeper bass. Can't explain it though.[/quote]
As semiconductors conduct differently at different temperatures, the amps are biased for optimum performance at their approximate operating temperature, instead of room temperature. This is why they sound better as the amp heats up. :)

[quote name='LawrenceH' post='908052' date='Jul 28 2010, 12:00 PM']Not wishing to derail this thread but speaker break-in is very real and easily measurable. I've experienced it, in VERY obvious fashion, with a Deltalite 2510 II. Note that Eminence (and other manufacturers) specify their speakers after 'conditioning' to account for this phenomenon. Makes me wonder about judging pristine new cabs in shops.

Re caps, I seriously doubt I could hear/care about the difference, but would be interested to A/B and see![/quote]
The differences between a "broken in" speaker and one which is not, are in nearly all cases less than the difference between two of the same speakers -- that is to say the difference is less than the manufacturing tolerance for that speaker. If you are able to provide accurate and repeatable measurements to the contrary, than please do so, I would love to see it. However, all data that I have seen to date indicates "speaker break in" to be a psychoacoustic phenomenon, and more likely has to do with your ears getting used to the way that speaker sounds, or simply just the individual hearing what they expect to hear.

Edit: Slightly further research brought up mention of a paper published by David Clark and available through AES, which discusses measurable "speaker break-in" that occurs in the first few seconds of use, after an extended period of non-use. This is likely not the sort of "break-in" you were thinking of however. :rolleyes:

Edited by escholl
Link to comment
Share on other sites

[quote name='Al Heeley' post='908272' date='Jul 28 2010, 03:17 PM']Tant caps have high tolerance (accurate value) and are (mostly) polar so cannot always be used to replace standard non-polar types. They can blow quite easily of you get them too hot whilst soldering or if you have the polarity the wrong way round.
Cheap ceramic caps can be +/- 10% of the printed value, which tbh makes little diff on a bass guitar tone pot.

[url="http://www.engineersedge.com/instrumentation/tantalum_capacitors.htm"]http://www.engineersedge.com/instrumentati..._capacitors.htm[/url]
Fascinating stuff indeed.[/quote]
Excellent - thanks.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...