Capacitors for Guitar

[sumgai]

Ah, I see my name has been invoked. (Chris, I'll get you for this! ;D)

Todd, as I see it, you're looking to reduce power supply ripple (hum) to its lowest level, yet you want to have sag. If I'm wrong, correct me soonest, but I'm gonna go on that assumption.

As noted above, these two criteria are mutually opposed. You can have sag (a form of compression), and you can have quiet, but finding the Holy Sweet Spot between the two is as much of an experiment as it is a defined calculation.

As I see your thinking process, you would like to use a resistor in series to act as a current limiter, in an effort to imitate signal compression. To put it bluntly, that doesn't work, and we'll dissect the reasons for that in the next several paragraphs.

To start out simply, a resistor can only drop more voltage as the current through it increases - it's not dependent on any other factor. Mr. Ohm wouldn't have a law named after him, were this not true. If the load wants 2 amps, and 2 amps (or more) are available from the power supply, then 2 amps will flow through the resistor, and the appropriate voltage drop will take place. Note that the only reduction that took place was in the voltage allowed to pass beyond the resistor - the current flow was unaffected. This is because a power amplifier stage requires, and consumes, current, not voltage. For all practical purposes, the voltage supply is fixed, and that reduces only as the current demand goes up, should there be some other component within the circuit that is also consuming power (voltage or current, doesn't matter).

In a tube amp, the filter caps can be pretty small, and still get rid of nearly all hum. But that yields a long time constant, and a high current demand will significantly impact the discharge rate. Again, the current outflow will remain the same, it's the delivered voltage that will be reduced (until the caps go down below the RC time-constant value). Contrast that with a solid-state power amp, where much higher capacitance values are needed to achieve the same reduction of hum (lower operating voltage is why this is so). Now the time-constant is so high that it's nearly impossible to demand enough current to cause the caps to start discharging below the rated voltage. Merely adding a low-value resistor to either kind of circuit will not have an appreciable affect on the time constant, so the same results will be noted as above.

See what I mean..... it's a never-ending battle, designing for an acceptable compromise between all the (known) factors. In short, a resistor can't act as a current limiter where the power demand varies significantly. The classic illustration of an LED using a resistor as a current limiter is slighly misleading - that LED places a steady demand on the supply, and the supply is already heavily regulated by other means. Here, a high value resistor is used to drop the available voltage, which in turn limits the current seen by the LED. We can thank one of Kirchhoff's Laws for this one.

In closing, it is my opinion that sag can be imitated, or modeled, in many ways, and some of them are so close to the original as to be virtually indistinguishable. But they aren't cheap, yet. As time goes on, the technology will get better, and cheaper, mark my words. But a simple resistor........... why doesn't every transistor amp maker use one, if it works as claimed by some folks? After all, they are cheap! ;D

End of discussion for today, got to go do some meat-space stuff. HTH!


sumgai

[toddw]

I see what you are saying Sumgai. I was only going to emulate the Sag induced by the internal resistance of the tube rectifier. Not from the cap depleting.

But I mentioned before, Matchless says the Spitfire is biased near class A. Actually, they pretend it is class A, and at low power I guess that's as true as it is in a Vox 15 watt. So why would increasing the filter cap size really matter here except in improving hum rejection. Won't this amp have a fairly consistant current draw?

BTW, this is where I read about the 100ohm resistor: www.aikenamps.com/ Under tech info, advanced, what is sag . . .

I like his reference articles, even I can understand them.

Todd

[sumgai]

Todd,

toddw said:

I see what you are saying Sumgai. I was only going to emulate the Sag induced by the internal resistance of the tube rectifier. Not from the cap depleting.

.......................

BTW, this is where I read about the 100ohm resistor: www.aikenamps.com/ Under tech info, advanced, what is sag . . .

I like his reference articles, even I can understand them.

Todd

Please note that I say nothing disparaging about Randall Aiken. Indeed, his writing style is very appealing, even to me. However, his lack of a classical engineering education shows in many of his articles, and this particular topic is about medium on the scale of "someone wasn't paying attention in class that day". Let's recap:

If a vacuum tube rectifier is used, sag is generated because of the internal resistance of the tube. Unlike a solid-state rectifier, a tube rectifier exhibits a fair amount of voltage drop which varies with the amount of current passing through the tube. In a class AB amplifier, the current drawn from the power supply is much greater at full power output than it is at idle. This large change in current demand causes the voltage drop across the tube rectifier to increase, which lowers the available plate supply voltage to the output tubes. This lowering of the supply voltage lowers the output power slightly in opposition to the larger input signal, making it act like a compressor. The lowered supply voltage also tends to decrease the available headroom, increasing clipping and changing the operating point of the tube dynamically. This type of sag can be emulated artificially in an amplifier with a solid-state rectifier by adding a series resistance, typically around 100 ohms or so..

Errrrr, Mr. Aiken........ point of order, sir? Have you forgotten that tubes in general, and specifically rectifier tubes, are heat-dependent devices, and as such they are not linear-response devices?

The fact is, a resistor is pretty much the only electrical component (outside of a switch) that responds in a perfectly linear fashion, regardless of input. No tube can make that claim, no matter how much the manufacturer might wish it to be otherwise. That inherent trait of the tube is what makes sag (the rectifier kind) possible, otherwise, it'd just be a uniform voltage drop across the board, no matter what the signal looked like. (He spoke of transients and such, which was valid, as far as he took it.) Uniformity is the name of the game for a resistor - if it were otherwise, every electrical circuit ever seen by mankind would be out to lunch.

In point of fact, every component in that amplifier contributes somewhat to the artifact we know as sag (or squish, for some folks), but for the output stage in particular, it's the output transformer, the load on that transformer (tubes and speakers), the filter stage(s), the rectifier, and the power transformer. We need to consider more than simple delivery and consumption of amperage, we must also take into account (in no particular order): heat; magnetic reaction; eddy current(s); frequency; stray capacitance(s); leakage (intended and otherwise); physical realities such as the quality of the parts themselves, and the assembly of those parts; intermodulation from proximity; the feedback loop (if existant); the list goes on and on.......... hell, I've probably forgotten at least half of the stuff I should be including here.

Long story short, it's easy to see for one's self what the real story is - a simple resistor and some breadboard time will either prove or disprove the merits of my ramblings.

HTH


sumgai

[sumgai]

toddw said:

I mentioned before, Matchless says the Spitfire is biased near class A. Actually, they pretend it is class A, and at low power I guess that's as true as it is in a Vox 15 watt.

There's the classic definition of what defines each class of operation, and there are the "local variations", if you will.

I'm not in a position to judge the merits of whatever Matchless has done, but I can tell you this - if a tube is biased at idle, and that adjustment is not set so that the tube is conducting the full available current, then it is not truly in Class A mode. However, a tube may be driven into Class A (presumably from Class AB) when the input signal is so large that it raises the bias voltage enough to change the tube's response characteristics. This holds true no matter what the rated output power might be, low, high or otherwise, and for both fixed and cathode bias.


BTW, I see that Aiken's article on biasing hasn't been updated in something like seven (7) years. Even Aspen Pittman has come back around to the engineering viewpoint, in that time. Ever read the inside flap of a Groove Tubes box, the one that mentions biasing? ;D

<diatribe mode>
It's a given that when one biases an amplifier, one must take into account several factors. The least important of those is the manufacturer's ratings, particularly the current draw at both maximum output and at idle. Why do I say this? Because those are guidelines, determined after looking at a small number of examples off the assembly line, but simple manufacturing tolerances throw the numbers right out the window.

Safety is another concern. Hogwash, I say. (Hark! Do I hear an Unkl-gram wafting its way hither? : That safety is for the life of the tube, not for the tone a player wishes to derive from using said tube. A mentor from my early days, passed away now, imbued me with the simple maxim of: "It ain't about what the book says, it's about what the customer wants. If he wants to blow up a pair of tubes every week, that's his business, and you have no right to interfere with his wants - it's his money. If that's the way to get the tone he wants, so be it. Who are you to pee in his Cheerios?" (Emphasis my mentor's, not mine.)

And so I go today. UnODir^© (Richard Marcinko, 1998), I bias a tube amp with a signal generator, a 'scope and a dummy load. I use 2KHz, and tune for the least cross-over distortion. But if the owner is right beside me, we use that only as a starting point, and I then hook it all up, and tell him to play. I adjust until he's happy with the tone he's getting, and only then do I present him with the bill. Most importantly, I don't go back and put a meter on anything - the owner is happy, so the job is done, period. (Except for the clean-up, of course.)

I guess that when push comes to shove, who's calling the shots here - a page in the tube handbook that says "Maximum 20mA bias current", or the magic mojo of toneful bliss that doesn't even know about the handbook? Or to be really crass about it, until the handbook has a bigger wallet than my customer, then I know who's driving my go-kart! ;D
</diatribe mode>

HTH too.


sumgai

[sumgai]

toddw said:

But I mentioned before, Matchless says the Spitfire is biased near class A. Actually, they pretend it is class A, and at low power I guess that's as true as it is in a Vox 15 watt. So why would increasing the filter cap size really matter here except in improving hum rejection. Won't this amp have a fairly consistant current draw?

In a Class A tube amp, the current drawn by the tube is constant, so there should be little visible charge-discharge cycling of the filter caps. Increasing their size to reduce hum even further is plausible, but I suspect there's a point of diminishing returns.

In the olden days, costs were part and parcel of any design decision, but filter caps weren't so expensive as to dissuade designers from using an appropriate value to get the job done. The values derived way back then (about 85 years ago) have proven true even unto today. The reason being, there will always be a small amount of ripple (hum that gets through the filter stage), no amount of capacitance can get rid of it all. The only thing to determine now is, how much hum is too much? And what's the cost of reducing it below the threshold that only 1% of the listening public might be able to hear?

Of course, even in a Class A tube design, there are still other stages of amplification to consider, when designing the power supply. In some cases, too much filtration may not be a good thing for the preamp circuits (or any effects circuits, for that matter).

Yet another design compromise, sigh. I need a "tears hair out by the roots" smilie. ;D

HTH (three)


sumgai

[toddw]

*JDL*
Goodness, don't tear out your hair over this. I'd hate to be responsible for your going bald.

My thinking on this topic is close to:

1) You can't control all the variables.
and
2) It's all good.
and of course
3) The more you know and understand, the better your chance of accomplishing your goal.

So yeah, I can see that a resistor is more linear. So even though it won't be the same, next amp I build I'll toss one in with a switch and a few silicone diodes, and see how it sounds versus a tube rectifier. Working on a guitar right now, so it may be a while, and my guess is rule 2 will apply.

Todd

[ChrisK]

However, a tube may be driven into Class A (presumably from Class AB) when the input signal is so large that it raises the bias voltage enough to change the tube's response characteristics.

I don't think that a tube can be driven into class A operation from class B (other than for half of a cycle ;D).

Class B operation infers bias at a point where the quiescent (idle) current is minimized. Overdriving at this point only caused clipping at the positive excursions by each tube as it runs out of gain or headroom (which is like aboot twice the excursion available in class A). (We can't drive them further into cutoff since they go there half-cycle naturally - Off is Off.)

Class A operation infers bias at a point where the quiescent (idle) current is at full (or nearly full) average current. Overdriving at this point can cause plate excursions into the regions normally inhabited by class B, certainly at cutoff (the cliff nearby), and in clipping (low ceilings).

"Class A operation is a linear mode ensured by the mid-point plate current bias point. It's two well-behaved kids on a see-saw.

Class B is a linear mode ensured by bias topology and (output) transformer." It's two teenagers on a see-saw.

Remember, all ""vintage""tube amp designs were aiming for accurate reproduction of the sound of the instrument, not the sound that we like to hear in our heads.


If you have hum issues, you might want to mind the filament circuit and its "bias voltages".

[sumgai]

Well Chris, awhile ago I was of the same mindset as you just wrote, but some time back, perhaps the middle of last year, you and The Unkster rode my butt pretty hard when I said pretty much the same thing.

I seem to recall that I lost that one, although I think I did so without too much rancor....... I hope.

At this point, I'm just gonna go downstairs, pack the truck with gear, and go play gee-tar with some friends, at a local open mic session. I'll think about this some more, tonight or tomorrow...... or when the cat stops purring, or when it stops raining, or whenever.

Mañana! ;D


sumgai

[toddw]

Enjoy your jam session Sumgai.

I'll keep watching this thread to learn more. I didn't have the guts to try and argue the point Chris stated. My understanding is far less complete than either of you two.
Todd

[ChrisK]

I guess that I'm saying that Class A operation of a particular tube is a subset of Class AB/B. If you overdrive a Class A stage, it may/will enter into Class AB and then B territory.

Class A is where, by design, the drive does not cause excursions into cutoff or plate current compression.

Class B is where the idle bias current causes the plate current to be nearly/in to cutoff for no drive signal. When driven, each tube in a push-pull topology conducts for 180 degrees only, which is combined in the output transformer. As a result, this has the lowest idle currents and hence, the best efficiency.

Class AB is a kinder drive overlap compromise between the two, for best signal combining in the output transformer and lower idle current.


Class A can occur in both single-ended and push-pull topologies. Conduction is 360 degrees.

Class AB is intended for push-pull. Conduction is greater than 180 degrees, but less than 360 degrees.

Class B better be used in push-pull (or non-audio applications). Conduction is 180 degrees.

Class C is an RF power amp. Conduction is less than 180 degrees.

Class D is digital audio PWM signal reconstruction in the output load. Conduction is 100 percent, some of the time. ;D

[andy]

Another change of tack here-

Is there a 'classic' tone cap for a precision bass? I have a vintage-ish pickup with Alnico magents and a 10.5Kohm resistance to put in, and may just re-wire the entire circuit. For a one-off, and for such a cheap component it is worth putting in the extra to get a top one, but what, if any might that be? I realise that the difference may not be earth shattering, but if there is a choice, I have a rosewood 'board and alder body, so a 60's type of thing may make more sense than a 50's one.

[malhomme]

sumgai said:

A more appropriate question might be, what value cap should you put back in there? Ah, but here we have an opportunity to do some true-blue, dyed in the wool, mad scientist-style experimenting. ;

sumgai

Hello.
I am a newbie but I'd like to share a recent experience.
I have a Steinberger converted to passive Pup.
The guitar has a 0.22 cap in it (nothing strange there) but it an orange cap.
It sounds VERY different than other guitar I have; first, it doesn't roll off the same way. It feels like the cut frequency is slightly moving, then it feels like as well as cutting high frequency, it beefs up medium...

Have you all
1) any idea what I am talking about
2 explanations ?

That makes me want to have the same behaviour in every guitar, since it makes for a very musical effect....

[sumgai]

mal,

Yes, what you've said is indeed familiar. The 0.22µf cap is normal - for an active circuit. I'd expect that in order to maintain a near-normal guitar-playing experience, you should change the value down to something on the order of 0.033 or 0.022µf, give or take a bit. Of course, your ears are the best judge of what you personally want to hear, but there's the more-or-less normal starting point for you.

As for the phenomenon of the cutoff point seeming to move as you rotate the tone control, I confess to being a bit surprised, as the response curve is the same for your cap (0.22µf) as for any other cap value, large or small. However, stranger things have happened, so it's only fair to say that your mileage is definitely varying from mine! ;D

HTH



sumgai

[stratomaster]

Here's a pic of the tone cap in my 2003 American Strat. Can you tell me what the value is? The pots are 250K.
Thanks,

[sumgai]

stratomaster,

That's not stock, whatever it is!

Looks to me like either 0.02 or 0.025µf, tough to tell.

If it sounds good, continue to use it. If not, your replacement cap should start at 0.022. Plan on going up or down one or two steps until you find the value that gives you the best tone.

HTH



sumgai

[maxa]

I have (uh.. had, before I went Nuts ;D ) quite a similar looking capacitor in my 2000 American Strat.

Your cap says
iC
.1K
250S

Mine says (can't take a pic, my cam cannot focus that close )
iC MSR
.022K250H

Now, I have some reason to believe that your cap is .1µf/100nf, as opposed to .022µf/22nf what was stock in my strat . "K" is the cap tolerance, +/- 10%. 250 would probably be the voltage, since caps are only made with certain increments.

That's quite large for a tone, I prefer using .022µf and a 500k log pot in my HSH strat (even with coil splits), since a .047µf cut too much upper mids, in my opinion. I'd guess a .1µ would cut them even more, making the guitar very muddy when turning the tone down. Of course, another man's mud is another man's Ultimate Tone.

------

Now to a question that's been in my mind for a while:

To cut a long story short, I've been thinking about a strat which would have a "neck-humbucker" (neck & middle in series) and a hot bridge single coil, and a tone only in bridge position. 3-way switch would be enough.

When the cap is disconnected, that is, going from bridge position to middle; will there be a "pop" or "crack", as I read in some thread here on GuitarNuts? With DC, the cap discharges, but I've no idea about AC...

Edit: I tested this with my HSH strat, and everything seems to working fine, no tone cut for the neck pickup, just the way I like it

[tommymodder]

I just carried out a mod to have the strats second tone work for the bridge as well. I couldn't get hold of a cap with as lower value as the one posted on guitarnuts. However I put it in anyway 0.033 uf i believe it is the result is that I do have a tone control for the bridge its just more subtle than the other two are.
It sounds really cool.

I was wondering if I had have used a lower value cap would I have more tone to dial in? At the mo it seems to give me a nice tone without sapping the highs and getting muddy. I like it even though I did it wrong... I just wanna know could it be better?

[D2o]

Jul 21, 2008 13:11:56 GMT -5 tommymodder said:

I just carried out a mod to have the strats second tone work for the bridge as well. I couldn't get hold of a cap with as lower value as the one posted on guitarnuts. However I put it in anyway 0.033 uf i believe it is the result is that I do have a tone control for the bridge its just more subtle than the other two are.
It sounds really cool.

I was wondering if I had have used a lower value cap would I have more tone to dial in? At the mo it seems to give me a nice tone without sapping the highs and getting muddy. I like it even though I did it wrong... I just wanna know could it be better?

Hi tommy, and WELCOME! to GN2!

Lower values allow more treble through (0.022 would be bright, and used in single coil pickup like in a Stratocastor)
Higher values allow less treble through (0.047 would be a little darker, and used in dual coil (Humbuckers) like in a Les Paul)

Could it be better? Tone is one of those subjective things, and I think your opinion must count for something here, right?

At 0.033, it sounds like you have a good compromise that has worked out pretty well for you - that's the main thing.

DD

[duendeyerbero]

What happens with the voltage of the capacitor? Does it have an effect on the sound? And can I use ANY voltage? I was buying capacitors and the guy asked me: "Which woltage do you need?" I was like ......Just give me 2 of every kind you have! jaja. Thanks for the help.

[simes]

Let’s see if I can get this straight.

The lower the cap value, the more treble it lets through, right? However, most people seem to recommend a 0.022 cap for SC’s – which are already bright – and a 0.033 or 0.047 cap for HB’s – which are already dark. Should this not be the other way round? Would it not be more logical to tame the ear-splitting highs of an SC with a higher value cap and emphasise the highs of an HB with a lower value one? I notice that GFS recommends this, i.e. 0.047 for SC’s and 0.022 for HB’s.

Another thing. I notice on the original GN site that in the “bridge tone pot” mod, that the mod is proposed for two reasons: 1. because there is no bridge tone pot on a standard Strat, and having one would be cool (OK, I get this), and 2. because using the same cap in parallel with two tone pots isn’t cool, and if we put in a separate cap for the bridge tone pot then we can remedy this.
What is the problem with the shared cap? How does it affect the sound? Or is it just assumed than any self-respecting GNer will want different value caps for neck and bridge tone?
In the light of all this, I’m rather confused. Now that I’ve got some nice pickups, am engaged in a hardtail conversion and am awaiting arrival of a valve amp kit, I feel I pretty much have the set-up I need, and that it would be a shame not to overhaul little things like caps and pots.
I have three SC-sized rails HB’s, one at the bridge that sounds like an HB, and cooler SC-sounding ones at the middle and neck. I have 500K pots. I forget what cap is currently in the guitar, but I have a spare 0.022 and a spare 0.047 hanging around. I could even bring myself to shell out a Euro or two for some more caps if necessary.

What to do?

[newey]

Simes-

Earlier in this thread, Sumgai noted:

Quote:

I've read that the lower the capacitance, the higher the "cutoff frequency" at witch the cap starts to roll off.

This is correct.

Quote:

Would 0.5 be to muddy?

I personally think so, but then again, I don't have your ears, so don't listen to me!

I think D2o's statement above is incorrect. A cap doesn't really "let more treble through"- think of a frequency curve, and of differing points along that curve where a given cap value begins to have some effect.

It's actually a more complex interaction than that, even, as the cap is part of a network- the pots and pickups also play a role here, too.

Your view of things is therefore essentially correct, but we fall into traps of language when we speak imprecisely. Again, think of the freq curve. It's not like the cap is a bouncer at the barroom door.

[simes]

Jul 7, 2009 5:42:13 GMT -5 newey said:

A cap doesn't really "let more treble through"- think of a frequency curve, and of differing points along that curve where a given cap value begins to have some effect.

It's actually a more complex interaction than that, even, as the cap is part of a network- the pots and pickups also play a role here, too.

Your view of things is therefore essentially correct, but we fall into traps of language when we speak imprecisely. Again, think of the freq curve. It's not like the cap is a bouncer at the barroom door.

OK, so presumably the sound would be exactly the same regardless of the cap value if the tone pots are on full.

To be honest, I hardly ever use the tone pots, and when I do it's just to back off the treble a little if things get a little shrill.

I wonder, then, whether it's worth worrying about at all (in my case).

[D2o]

Jul 7, 2009 7:48:15 GMT -5 simes said:

OK, so presumably the sound would be exactly the same regardless of the cap value if the tone pots are on full.

To be honest, I hardly ever use the tone pots, and when I do it's just to back off the treble a little if things get a little shrill.

I wonder, then, whether it's worth worrying about at all (in my case).

Newey is correct about D2o being incorrect with the language.

Sometimes D2o is a bit of a kylehead.

Nevertheless, I do not agree with your presumption that the overall tone will be unaffected, regardless of the cap value, with the tone pot fully opened.

They are still part of the circuit and you should stay within the typical parameters, suited to your application.

D2o

[simes]

Back to my original question, then.

What would you recommend for a SSH guitar with 500K pots? The main consideration apart from the set-up is that I never use the middle PU alone, and would therefore probably opt for bridge and neck tone pots. 0.022? 0.047? Shared cap? Two different values?

[D2o]

Tone is in the ear of the beholder!

Funny that you mention shared cap, though, as you could have more than one option - have a look at ChrisK's "Free Woman Tone".

If you wanted to keep it simple, I would just stick with the 0.022uF cap, as usual.

D2o

[sumgai]

To recapitulate:

A cap doesn't so much as cut off the highs as it prevents the lows from coming through. In order to get more of the lows, we need to have a larger value of capacitor.

That said, let's look at how a tone circuit is wired into a guitar.... Oh, hey, looky here, it's wired in parallel with the outgoing signal. That means that some of the signal, the highs in fact, are going to have a very easy time of getting to ground (the signal return), whereas the lows will have a much tougher time of getting to ground - the cap's value isn't large enough, so they'll have to take the "harder" road of going through the amplifier's first stage in order to get back to ground (the signal return). (And it needn't be an amplifier, it could as easily be an effects unit of some sort.) The end result is that as the tone pot is turned down, we hear a tone that's less bright, and hopefully that's what we wanted.

Now that could end it right there, but I'm feeling my oats today, so.....

Discussion:

When you think about it, a lot of our discussions have been "bent" by that language thing, because we aren't applying component theory in our circuits in the most direct way - we're actually applying them in sometimes obtuse ways, even sometimes in outright "impossible" ways. When we do that, the circuit behaves as we desire, but the description then becomes bizarre. EE's have this all worked out, and short-cutted to a fare-thee-well, but laypersons have to muddle through it. Do that often enough and it becomes second nature, but doing it only once in a great while makes for Excedrin headache #6.

Now, the net effect for simes' purpose is this: If you insert a capacitor of, say, 0.022µf along with a pot of, say, 500KΩ, you'll have a pretty bright combination to start with. The beauty here is, you can reduce that brightness by simply turning the pot down from maximum (10) until it reaches a point that sounds good to your ears.

What happens if you use different values? Using a lower-valued pot, you don't get as much brightness to start with. The tonality is approximately the same as what you'd get with a 500KΩ pot that is turned down to 5 or 7-8 (linear and audio tapers, respectively).

Inserting a higher valued capacitor such as 0.033µf unit instead will not tend to reduce the highs quite so much at the tone pot's maximum (compared to the 0.022µf part), but when the pot is rotated downwards, the effect of killing some of the highs is more noticible. Going ever higher in value, the effect becomes drastic, comparitively speaking. At 0.047µf, it can be so dull as to be unusable, at least for some folks.


The upshot is as advertised - season to taste! Rather than linking to past posts/threads, lemme say this: When starting out, remember what your axe sounded like before you hacked into it.... Was it shrill? Was it dull? Was it just right? If the last of those three descriptions seems closest, then leave the bleeping components alone! If it was one of the first two, then deal with it accordingly, as noted above. The easiest thing to replace is a cap, so mess with that (them) first. If you can't get what you want here, then start in with the pot(s).

A shared cap is mixing a pair of signals that you might not otherwise want mixed. In the case of a Master Tone, it can't be helped, and is usually acceptable. However, you can sometimes get some interesting tones by having one pickup running full-out mixed with another pickup whose tone control is "dialed back" somewhat. This latter possibility is why we Nutz like to advocate for separate caps - we can do it, so why not? After all, it's not like we're saving more than a dime, and another 2 minutes of soldering time, eh?

I trust that puts paid to the topic, no?

HTH



sumgai

[newey]

I trust that puts paid to the topic, no?

Not quite. A graph is worth a thousand . . .

ChrisK's The Passive High Cut Tone Control

[ashcatlt]

And you can make your own graphs, too.

Playing with that a little bit reinforces a point that we've heard around here before. Until the tone pot is turned down a ways, the tone cap itself has only very subtle impact on the overall tone. It's mostly the cable capacitance that dumps the high end when the knob is up over 5-6 or so.

I say, choose your tone cap to give you the desired "0 tone" and look to other factors (like pickup choice, pot value) for the "10 (or 8) tone".

[sumgai]

ash,

Jul 7, 2009 23:45:44 GMT -5 ashcatlt said:

I say, choose your tone cap to give you the desired "0 tone" and look to other factors (like pickup choice, pot value) for the "10 (or 8) tone".

That's an excellent way to put it. Kinda makes me wish I'd said that! ;D




sumgai

[flateric]

You can say it next time, Sumgai.