Carvin AP-6 pickup used on early Mosrite?

[Dnepr]

I think Bob has duplicated construction of the AP-6 very closely and his winding on the present version measures in the mid 8's (correct me if I'm wrong here)

MIne are 8.45 and 8.54.

The unique sound is rather a combination of the hollow/semi-hollow body and the AP-6. You don't get the big "Goink" Maphis sound on a solid body guitar.

I agree with that. I mounted mine on my R.C. Allen archtop as an experiment and the sound was very close...
These pickups are hi-fidelity, and very bright. That tends to be a little off-putting to your average "modern" guitarist. Read: many of my friends and clients do not like the sound.
Every little nuance comes through, so you have to adjust your playing to suit . Matched with the right strings they are unbeatable as far as I'm concerned.

[Mr. Bill]

Terry:
Thanks for posting these photos, I'd never seen the insides of one of these before.

These look similar to the insides of a Mosrite and they look like they are based on the Gibson P-90. The Carvins even have the two small cover mounting screws located between the polepieces.

The magnets look to be Alnico 5's. The only unanswered question is what wire gauge was used? If the coil measures 3-4K in dc resistance, that would lead me to guess that they used a larger gauge wire than either Gibson or Mosrite, as the coil form appears to be fully wound. Maybe something like 40 gauge?

Just my 2 cents.

[Deke Dickerson]

Hey guys,

I've been out of town a couple days so I missed this thread. I'll pitch in my two cents about Carvin AP-6 pickups....

I believe that the main thing that produces the "tone" so identifiable with the Carvins is their brutal simplicity. Carvins are like the Model T of pickups, but that's not a bad thing in my book.

The main thing that is different about them from a P-90 or similar pickup is that the pickup is mounted only to the TOP of a flimsy plastic cover, it doesn't have a plate on the bottom anchored into the guitar like a P-90. Therefore, like a Strat pickup that's mounted only to the pickguard and not the guitar, there is a lot of resonance. It's a much different attack than a pickup that is screwed into the wood of a guitar. That's the secret of the Carvin pickup sound if you ask me. It's just hanging there off the plastic cover by two little bitty screws and that's it.

The other thing is the pickups were originally wound with NO BOBBIN OR COIL FORM, they were put on a jig and wound with coated wire. When they were taken off the jig, it was just a loose bunch of wire that they put MASKING TAPE around (see Terry's photos). That's it. No mojo like the Fender or Gibson bobbin material and coil form. As simple as can be.

Terry has mentioned the odd difference in the pickup impedence. I have four original Carvin pickups (white cover versions) and they measure right around 6.5 K ohms. Terry has four original Carvin pickups, made later, with black pickup covers, that all measure much lower, 3.8 to 4.6. That's pretty weird, but I have a feeling that whoever was winding these pickups probably made a batch one day that were all one ohm rating (number of turns) and the next time they went to make a batch they were different. That's just my guess.

The point is that the pickups all kind of sound the same, and I think personally the secret is that they are suspended only from the plastic pickup cover and don't have a bottom plate.

I sure do like the way they sound, but the Clapton/Page/Beck guys might not dig 'em at all....

Deke

[Deke Dickerson]

Oh, and just noticed Mr. Bill's post--the wire used on Carvin pickups is like fine angel hair--extremely thin and fragile wire, supposedly 46 or 48 gauge wire. They didn't do much strengthening when it comes off the coil either, it's not uncommon to find a Carvin pickup where the wire has been broken leading off the pickup....

Deke

[Veenture]

Reading these interesting facts / insights / ideas always stimulate further thinking -with me at least. Thanks guys for sharing with us here!

About guitar amplification in general, I would think that the basic idea when Gyro Gearloose started inventing pickups and putting them under the strings of guitars, was to merely amplify the soundwaves produced by the strings. Nothing more, nothing less.

This is a fantastic invention in itself but the TONE thing was obviously discovered and appreciated at later stages during the development of the pickup when people started experimenting and refining them for purity of sound (and later even distorted sound!), output and so on.

And of course, tone is a matter of taste too. I like different tones for different moods...will always love 'that' FENDER tone but also that su-weeeet MOSRITE 'mid position' tone on the Ventures models and others...

[dubtrub]

I'm curious if maybe the tone on the Maphis recordings are due to the microphonics of the pickups? I've been playing on Artie's single pickup Mosrite guitar and that thing is extremely microphonic. With the volume set at a medium level, you can knock on the body or neck and it will amplify quite loudly through the amp. Other than that, the guitar has a beautiful sound.

My thinking is, those early Mosrite and Carvin pickup's were hand wound probably with only a motor driving the bobbin but the string tension and string guiding may have been provided simply by thumb and finger pressure. By having an uneven coil wrap with varying tension would make a loose coil which would make them microphonic. Actually all the very early Mosrites I played have that extremely microphonic effect but the later factory wound pups are not nearly as much. Other than microphonic, the earlier pups sound better to my ears.

[Deke Dickerson]

The way I understand those Carvin pickups were made, the key ingredient was the COATED wire. It was coated with lacquer and that's the only reason the thing held together supported only by masking tape!

They supposedly had some sort of wood form they would wind the pickups on, then they would remove the loose coil from the form--bare wire!!--and wrap the bare wire coil with masking tape, then mount it to the cover with only two pickup screws from the top.

As far as microphonics go, they vary. I haven't had too much problem with most of them, and the reissues seem pretty good too. All are SLIGHTLY microphonic but they don't "howl." I have one Carvin pickup, though, that howls with feedback when it's mounted to a guitar, it works but the microphonics are amplified 100%. Not sure what would cause that.

I don't necessarily think that the MICROPHONICS have anything to do with the tone, but I do think that the RESONANCE has a lot to do with the tone--i.e. what I was talking about with the coils only supported by the two screws mounting in the pickup cover from the top, and not having a metal plate underneath them.

Deke

[oipunkguy]

very interesting, very. thanks everyone.

[Curtis Novak]

Hey Deke,
Yeah I have restored a number of pickups like these they are way cool. It took me a few tries to successfully wind a no bobbin coil. Airline and Harmony also did these types. It is tricky getting the coil off the jig without losing its from, and breaking one of the wires.
They do have a way cool tone. As for potting this tricky. What most people do not realize it is not the coil that is the source of the microphonics, but rather rigid parts that resonate against one another. If you have ever played a Juice Harp you get a great tone with the metal frame pressed against your lips, but if that metal frame touches your teeth you get an awful buzz. That buzz when you have 2 rigid materials allowed to have loose contact and the coil attached to them. So as the coil gets amplified it causes them to resonate which excites the coil more creating the feedback loop. So yeah when someone pots a pickup it does fix the microphonic problem because it fuses all the rigid parts together with the potting material so they all resonate as a unit and not independently. The problem is when you pot the whole pickup you also drastically change the resonance of the coil b/c it too is all glued together. Think back to the Juice Harp if you dipped the whole harp in a plasti coat it will no linger buzz your teeth, but you will loose MUCH of its twang. The better method it to fuse all the parts together with potting material, hot glue or some such. Over the years I have taken apart so many pickups and you would be surprised how many GREAT sounding pickups has such loose wraps that were almost falling off the bobbin. They were quiet b/c all the parts were secured. Fender is actually some of the ONLY pickups that were potted.

curtis

The way I understand those Carvin pickups were made, the key ingredient was the COATED wire. It was coated with lacquer and that's the only reason the thing held together supported only by masking tape!

They supposedly had some sort of wood form they would wind the pickups on, then they would remove the loose coil from the form--bare wire!!--and wrap the bare wire coil with masking tape, then mount it to the cover with only two pickup screws from the top.

As far as microphonics go, they vary. I haven't had too much problem with most of them, and the reissues seem pretty good too. All are SLIGHTLY microphonic but they don't "howl." I have one Carvin pickup, though, that howls with feedback when it's mounted to a guitar, it works but the microphonics are amplified 100%. Not sure what would cause that.

I don't necessarily think that the MICROPHONICS have anything to do with the tone, but I do think that the RESONANCE has a lot to do with the tone--i.e. what I was talking about with the coils only supported by the two screws mounting in the pickup cover from the top, and not having a metal plate underneath them.

Deke