Polepiece effects on tone

[hewo]

the amp is an infinitesimal load because of the impedance miss match, you can throw lows into high impedance, not vice versa.

so when you say amp is a load, yes, infinitesmally.

the 800 ohm coil impedance sounds not to standard, it must be a new venture that not too many folks adapt into. how do you generate bass with only 800 ohms impedance? sounds like the opposing spectrum of the barcus berry hotdots that required specialized electronics interface for the amp.

[David Schwab]

You don't think an amp qualifies as a load?

For crying out loud....

I said:

You don't need the load of the volume pot to get an output, and this can be demonstrated by the fact that you can wire the pickup directly to the output jack. The pickup will always be feeding a load as long as you have it plugged into an amp.

You were talking about the pickup needing the volume pot as a load to produce a signal. That's incorrect. I said you don't need a volume pot... the amp was a load. Go back and read it again.

You said:

To get a useable output we need to put a resistor across the leads to act as a "load".

Come on, that's just wrong. There's lots of input stages that don't have a resistor to ground... FET's and op amps can have pretty much infinite input impedance. A unity gain buffer (voltage follower) made from an op amp doesn't need, or even have, a resistor at the front end. It draws no current from the source and presents no load.

Also... if you don't plug the pickup into anything, what difference does it make as to whether or not it's producing a signal? That's like the old question "if a tree falls in the woods and there's no one to hear it, does it make a sound?"

My personal opinion is I don't want my instrument to sound different depending on what front end it's plugged into. So I like to keep the pickups isolated from the amp, and that's what you achieve with a buffer.

If they "worked fine", you wouldn't need a preamp.

That's your opinion. What works well for one person is another person's crap. Do you not understand the concept of low impedance pickups? They work better than high impedance pickups if you are looking for a wide and flat frequency response, and you aren't going to get that with a lot of windings. I guess there's a lot of active pickups on the market because they don't work well, right? Also as I mentioned low impedance microphones work even though they are about 100 Ohms. I don't need a preamp if I plug into a low impedance input, like a mixer. But as I said we have standardized on high-z gear. Les Paul also wound low impedance pickups for his personal guitars.

I understand, you're suffering from the "big fish in a little pond" syndrome. You're used to wowing your customers with your techno-babble, but I'm not one of your customers. At this point you have so little credibility, I wouldn't even accept an apology.

Excuse me? I have no clue what you're talking about or even why I would need to apologize to you. I'm not suffering from anything at all. You don't know me, so that statement is invalid.

Credibility? Let's look at that word... "the quality of being trusted and believed in." I have instruments and pickups I designed and made that anyone can look at and listen to. So if I say I build basses and pickups and they play and sound great (subjective of course...) I can back that up. That makes me credible. That's known as integrity. Talk is cheap. What do you do? Have something to show us?

I don't make a living doing this stuff anymore, so I really don't care. I'm not trying to prove anything at all. But I've been doing it for a long time and know a thing or two, as do others here, and I'm only here to share what I know and help people out if they need it. Why are you here? To make yourself look good?

This is a public forum for discussions about pickups and such, and you came here with the attitude that you were teaching the pickup makers something we don't know. You can voice your opinion on anything, and I can agree or disagree if I choose. I was pointing out that some of your post wasn't quite correct.

...but that tends to confuse musicians.

You apparently wanted to come off like some expert and don't like being corrected.

I don't need to "wow" anyone with anything. I was stating facts, not conjecture. I build and play basses and guitars and make pickups and electronics for them in my spare time. I have customers I have had for the past 20 years because they like my work. If someone is interested in what I'm doing it's because they like what they hear and see, and has nothing to do with "techno babble" ... I'm using the same "techno babble" that you might find someone like Rick Turner using by the way ... but I guess you know more than he does right? Actually you were spewing a lot of "techno babble" yourself, were you not?

Do you even know who Rick Turner is? He's the guy who pretty much invented "active" pickups and boutique basses by winding 1500 turns of 40GA wire around a magnet and then used a preamp to bring it back up to line level. And not only do these pickups "work fine" they are well known for the clear tone and sell on very expensive Alembic basses.

Maybe I can come off a bit brusque or blunt, but to tell you the truth there's so many "internet experts" on these forums that say such crazy things (like active pickups are active because they use electro-magnets!) that I find myself getting impatient. I'm a friendly person and the internet does not convey such things easily. But I didn't even say anything to you to warrant you getting yourself worked up over.

I'm not here looking for acceptance and don't need to have any credibility. I'm not trying to prove anything, but I like giving people info if that helps. I don't pretend to know everything, but I know what I know, and the more I learn the less I know! But we can learn something new everyday. You have to be open to it however.

[Just Bob]

For crying out loud....

Well, you have to admit the guy has a pretty nice picture of a tube next to his name. That must count for something. And, despite his apparent lack of expertise, he does make up for it with his depth of conviction. If people had to be right, we wouldn't have politicians and where would we be then??

[David Schwab]

Well, you have to admit the guy has a pretty nice picture of a tube next to his name. That must count for something. And, despite his apparent lack of expertise, he does make up for it with his depth of conviction. If people had to be right, we wouldn't have politicians and where would we be then??

It's a nice picture of a tube too. Maybe I need to smile in my picture...

Hey, I'm just wondering why he got so bent out of shape in the first place...

OK.. back to winding 1000 Ohm pickups....

[Glass Snuff]

I was trying to simplify things in an attempt to explain something. It seems to me the fact that your "pedantic" reply wasn't well received should not be confusing, but then again, if you possessed that level of understanding you wouldn't have posted in the first place.

Sorry to hear you're no longer making basses. However, that should in no way impune your expertise.

Yes, I'm a newbie here, but I've been around the internet since before there was a WWW, which means long before there were forums such as this. I can, I think, reliably predict people's reactions to me. A few will be thankful for my input and seek my help, but most of you will think I'm an asshole.

[David Schwab]

I was trying to simplify things in an attempt to explain something. It seems to me the fact that your "pedantic" reply wasn't well received should not be confusing, but then again, if you possessed that level of understanding you wouldn't have posted in the first place.

Who was it not well received by besides yourself? I was also trying to clarify some thing that maybe some people don't understand well. NightWinder was busting my chops, but I guess the last time I went on a rant gave me a bad rep!

Sorry to hear you're no longer making basses. However, that should in no way impune your expertise.

I didn't say I'm no longer involved in lutherie, I said I don't make a living at it anymore. I have a "regular" day job, like some other people here do, and I do lutherie on the side. I have a family to support, and making guitars and pickups doesn't always pay the bills. Neither does playing music, but I do that too. In the end they all contribute to an income, but I meant making basses, et al, is not my sole livelihood. I actually just started my business back up after a long hiatus... so If I start to do more basses than graphics, then that statement will change.

Yes, I'm a newbie here, but I've been around the internet since before there was a WWW, which means long before there were forums such as this. I can, I think, reliably predict people's reactions to me. A few will be thankful for my input and seek my help, but most of you will think I'm an asshole.

I wasn't trying to start anything with you, and I didn't insult you or say you don't know anything. I was just correcting a couple of points that were probably due to you simplifying things, which is fine. I was trying to contribute to your info, not dis you. A volume pot can be one persons tone shaping bliss and another person's mud maker. All depends on what your after. What I'm doing is probably very different from what other's are doing here pickup wise. But we can all find bits of info that can help us from time to time.

We are all assholes here from time to time... it's the nature of creative people!

[Glass Snuff]

Well said, Dave. Not sure exactly what tipped the scales, but suddenly I feel like I've been baiting you, and I apologise for that.

[David Schwab]

Thank you.

Back to talking about wires....

[Steve Conner]

You guys all forgot about the most important factor in pickup tone! The resonance between the inductance of the pickup and the capacitance of the guitar cord (plus any caps in your tone pot) creates a 2-pole low-pass filter with a resonant peak. The size and location of the peak depends on how hot the pickup is wound, and how long your guitar cord is, as well as its capacitance per foot. It also depends on your volume and tone pot settings in a complicated way.

Cranking the tone control to minimum tends to lower the frequency of the resonance drastically and make the peak bigger. With really hot wound pickups it can honk almost like a parked wah-wah. These hot pickups will probably have the peak in the midrange even with both knobs up full.

The volume pot damps the resonance, both by its resistance to ground at full volume, and by its isolating the pickup from the cable capacitance at part volume. A bright cap lessens the damping. The input impedance of the amp damps it too.

I guess that's why folks like active pickups, because they want their instrument to sound the same no matter whether they use a 10 foot cord or a 50 foot one. An active buffer built into the guitar can present a very low load capacitance, and presumably give the hottest humbucker a bright top end. (unless self capacitance of the coils limits it)

I never got the point of active pickups on bass, unless it's to sneak some extra EQ past sound guys who insist on taking a DI from the input of your amp. ;-)

IMO. YMMV.

[Glass Snuff]

Really, I think one of the Moderators should split this thread off at post #7 and title it "The effects of pots, etc," or something. We haven't mentioned polepieces in a long time.

(and then delete THIS post, which will no longer make sense)

[David Schwab]

I never got the point of active pickups on bass, unless it's to sneak some extra EQ past sound guys who insist on taking a DI from the input of your amp. ;-)

Here's my take on the subject.

I think there's two schools when it comes to bass players. One is the hi-tech bunch, started by Alembic, and its many followers (that would include me) and the other would be the vintage bunch.

The hi-tech bunch want ultra hi-fi pickups and electronics, and generally use a wide range tone with extended top end.

The vintage bunch like old school tone and often use flat wounds and tube amps.

So if you look at the time line... back when the P-Bass was king (mis 70's), DiMarzio came out with the Model P, which gave more highs and output. The next step in that evolution was Hi-A pickups and then the EMG-P. These were all designed to give a wider range tone from the bass.

Back when I started playing, most people played a P-Bass... I played a Rick... I grew up with, and love the Motown bass tone, but I was looking for a very modern bright tone... so I was always tinkering with my basses.

Being that bass amps pretty much sucked up until fairly recently, a lot of bass players were always looking for more accurate sound, and went so far as using things like Crown power amps and a custom hi-fi speaker setup.

I think a lot of bass players are fascinated with hi-tech gear, because bass players always had less choices... we get the corner in the music store, and the back of the catalogs! Fewer choices of amps, strings, pickups, etc. That's changed over the years of course, but I still see that fascination with things like 11+ string basses and on board electronics. And you can see that guitar players seems to be more into vintage styled gear, while basses tend to look more "futuristic." Look how many more headless Steinberger basses you saw compared to guitars back in the 80's.

So the way I got into making pickups was I was building basses, and decided to use EMG's, since I had been using them in my Ibanez 5 string. I started not liking the tone of the EMG's because they sound too processed.. they seem to have their own EQ curve and sound compressed. I wanted the most transparent sound, so I started trying different pickup designs.

It's very different from what you expect from guitar pickups... in a guitar you want that interaction and resonant peaks. In a bass you want a more clear smooth tone ... less peaky. I figure if you start with more frequencies and a clean tone, you can dirty it up later.

For me, when I'm playing something like a Fender bass, I'm always trying to get more tone out of it.

I use very little EQ at my amp, and some times I plug directly into the PA. Lately I've been bypassing the preamp on my amp entirely and plugging into the effect return.

[Steve Conner]

Hi David, that's very interesting! I started out as a guitarist, but my only experience with gigging is on bass. (I wanted into the band bad enough that I offered to play bass to get the gig.) I always liked listening to funk and Motown stuff, so my tone of choice would be to fart through an underpowered tube amp and 2x15" cab. I like how a tube amp adds a bit of grind and excitement when you play harder.

Having said that, with the kinds of gigs we play, I usually end up going through someone else's bass rig anyway. And, I'm also a big Stanley Clarke fan, but I know he belongs to the Alembic school, so go figure.

The bass I use is the old budget model Peavey Cirrus with passive electronics and two pickups of goodness knows what kind. They just look like plastic oblongs with no visible pole pieces, and I never did figure out how they worked. (Having read this thread, I guess now they might just be a coil wound round a bar magnet.) I'd love to try the big-ass humbucker that comes fitted to the Music Man Stingray, but it'd never fit without serious routing.

I tinkered with a few things, like wiring the pickups in series, but the output got way too hot and made the front end distort on every amp I tried it with. In the end I wired it like a guitar, with a 3-way LP style pickup selector switch and a single volume and tone.

The hi-techest bass I ever owned was a Hohner 5-string with the Steinberger headless system. I wired it so I could switch between active and passive in case the battery ran out, so I got to compare the effect of the active circuitry. The only thing that really stood out to me was the treble boost that gave more of a piano-type sound on high notes instead of a monkey hoot.

In a vain attempt to stay on topic (maybe a mod should split us?) did anyone see the Duncan Parallel Distortion humbucker? Each pole piece is two rectangular prongs made of thick sheet steel. I've no idea what that's supposed to do.

[David Schwab]

Hi David, that's very interesting! I started out as a guitarist, but my only experience with gigging is on bass. (I wanted into the band bad enough that I offered to play bass to get the gig.) I always liked listening to funk and Motown stuff, so my tone of choice would be to fart through an underpowered tube amp and 2x15" cab. I like how a tube amp adds a bit of grind and excitement when you play harder.

I like that tone too, but I don't want that to be my only tone I get. I'm a big Jack Bruce fan... He was pivotal in how I play bass. My first big bass amp was a Peavey "Bass" ... their first model. It had a wonderful distortion feature that nailed that Jack Bruce/Felix Pappalardi/Tim Bogert tone, and that's why I bought it.

These days I use an old Blue Tube pedal that has a 12AX7 in it when I want some grind. I think it was from having too many under powered amps over the years that makes me crave clean headroom! I have a Mesa 400+ rig that I stopped using because it would get too crunchy when I dug in. Maybe I just play too loud? My first real bass amp was an Ampeg B-15n... lovely sounding amp, but totally unsuitable for gigging with a drummer! I stay away from tube amps these days, they just feel and sound too mushy. Great for guitar though.

Having said that, with the kinds of gigs we play, I usually end up going through someone else's bass rig anyway. And, I'm also a big Stanley Clarke fan, but I know he belongs to the Alembic school, so go figure.

I'm a big Stanley fan too. It was trying to get that Alembic tone that drove me to mod my 1972 RIC 4001 bass to death, and later what made me decide to build my own bass... I just wasn't finding what I wanted--that I could afford-- in commercial basses. Same holds true for pickups.

The bass I use is the old budget model Peavey Cirrus with passive electronics and two pickups of goodness knows what kind. They just look like plastic oblongs with no visible pole pieces, and I never did figure out how they worked. (Having read this thread, I guess now they might just be a coil wound round a bar magnet.) I'd love to try the big-ass humbucker that comes fitted to the Music Man Stingray, but it'd never fit without serious routing.

Jeff Berlin played a Peavey Palladium for a while. I'm not familiar with either bass, but he got a great tone out of that bass. There's might be poles under the cover... it's hard to say what's inside a closed cover pickup. Look at EMG.. inside their soap bar pickups they have stacked Jazz pickups, split P pickups, and standard humbuckers. The Peavey might use steel blade poles... I don't think too many pickup makers wind right on the magnet.

I tinkered with a few things, like wiring the pickups in series, but the output got way too hot and made the front end distort on every amp I tried it with. In the end I wired it like a guitar, with a 3-way LP style pickup selector switch and a single volume and tone.

One of the easiest ways to get more tones is to add a preamp. I have a stacked bass/treble setup, and I'm always changing my settings from song to song, along with mixing my two pickups. I think having two volumes is better than a switch on a bass.

The hi-techest bass I ever owned was a Hohner 5-string with the Steinberger headless system. I wired it so I could switch between active and passive in case the battery ran out, so I got to compare the effect of the active circuitry. The only thing that really stood out to me was the treble boost that gave more of a piano-type sound on high notes instead of a monkey hoot.

If all depends on the pickups and the preamp. It souldn't really alter the tone that much when the tone controls are set flat, besides what effect buffering the pickups has.

In a vain attempt to stay on topic (maybe a mod should split us?) did anyone see the Duncan Parallel Distortion humbucker? Each pole piece is two rectangular prongs made of thick sheet steel. I've no idea what that's supposed to do.

It's the same concept as a Fender bass pickup. Fender first had a single pole under each string, and the attack of the string sometimes made the amps at the time break up. So they switched to two magnets on either side as a way to soften the attack.

I remember reading that Duncan did this for tremolo users, and I think it was so when you do a dive bomb, the string wont smack right on top of the pole. Also the string hight is changing as you press your bar in, so I supposed this was to try and even that out.