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Les Paul Jr P90 from 1955

When I was contacted about repairing a Les Paul Jr P90 from 1955 I was naturally very keen.

P90’s are very interesting pickups. They have a single wide flat coil usually of around 10,000 turns of AWG 42 wire but the really fascinating aspect is the magnets. They have 2 bar magnets underneath the pickup (a PAF just has one) causing a much wider magnetic field than other single coil pickups.

To put it simply – P90’s hear more string than other pickups. Hearing more string gives a fuller, fatter sound and that distinctive woody P90 tone. Not everyone likes them but those of us that do absolutely love them.

I make my own version of the P90 called the ‘Sassy’. It’s a full fat version of the P90 with alnico 5 magnets with all the warmth and plenty of grunt that you find in the old Gibsons.

So I’m always interested to have a good look at a genuine vintage pickup especially from a Les Paul Jr P90 from 1955. I’m a big fan of the Juniors.

P90 Les Paul Junior 1955.

The pickup was sent to me because it wasn’t working and both the customer and myself suspected it might need a re-wind but I never jump to conclusions. It could be just a dry joint on one of the hookup wires – always worth checking.

1955 P90 pickup underneath

As you can see the hook up wires look a bit scruffy so I re-solder and test, remove the wires and test, remove the tape and test – still nothing. The next step is to start removing a few layers of the winding wire just in case there’s a break. There was no obvious break. The problem was deeper inside the pickup – this one is a re-wind.

vintage guitar pickup. P90 1955

Now, I talked about magnets earlier, take a look at these two. Firstly they’re wonky. Some amazing Gibson vintage tonal secret or just being a bit sloppy in the factory? Probably the latter.

But for me the most interesting part is they’re rough cast alnico 2. For this era I was expecting Alnico 5.

Alnico rough cast P90

Alnico 2 have a smoother, purer sound than the more powerful rougher sounding alnico 5’s.

So after I re-wound this lovely old pickup I started experimenting. I started winding P90’s with Alnico 2 magnets and from that was born a new pickup set in my range – the “Cool 90″.

Vintage P90 plain enamel wire

It’s cleaner than the Sassy, less grunty but still full and fat sounding.

Ideas can come from anywhere. It reminds me of the quote from Picasso – “Inspiration exists, but it has to find you working”

Gibson P90 vintage no cover
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Here’s the ‘Sassy” –

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‘68 Telecaster Bridge Pickup

Fender Telecasterbridge pickup from 1968

I repair quite a few old pickups and thought you might be interested in this ‘68 Telecaster Bridge Pickup.

‘68 Telecaster Bridge Pickup

As you can see it’s looking pretty tired. I quite like seeing pickups like this – it’s clearly given great service for decades. This is just wear and tear and the sign of a happy life and although it isn’t working now there’s no reason why it can’t be made good for a few more decades.

guitar pickup

One of the first things I noticed is the black tape. Underneath it is the original waxed protective string. I’m not sure why someone added that.

old guitar pickup
Tele pickup bridge plate

The plate underneath has aged fantastically but as you can see the earth wire is missing from it. I re-solder the connections just in case there is a dry joint but the pickup is still dead.

broken pickup

I suspect this is the fault- the top plate has warped over time and the corrosion has got in and damaged the windings. That top plate looks like a skateboard deck – it should be flat! This pickup is going to need a re-wind.

'68 Tele date

With the back plate off you can clearly see the date.

guitar pickup corrosion

And here it is, this is the problem. With the windings cut away you can clearly see that the corrosion on the pole piece has spread into the winding. There’s a bit of wax in there too from when it was potted originally.

So here’s the plan. I need to flatten that top plate back. Then clean up the pole pieces. I need to do something about the corrosion. And finally re-wind the pickup to original spec. And most importantly make it look like nothing ever happened.

pickup lacquer

Cleaning the poles is easy, then I flatten the top plate and glue it in place with super glue. Originally it was just a push fit. Then I treat the rust with some anti rust stuff. Here you can see it masked off so I can give the poles a couple of coats of lacquer.

Tele pickup

Next I wrap the poles with thin tape. I want to protect the windings from future corrosion. I want this pickup to play hard for another 50 years.

Telecaster Bridge Pickup

Then it’s re-winding and wax potting and finally replacing the original string.

Of course, I forget to take a photo of it with the string on.

If you need any pickup repairs please contact me through the website or give me a call 021912678

‘68 Telecaster Bridge Pickup

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Gretsch FilterTron – a look inside

The Gretsch FilterTron is something rather special. Originally designed in 1954/5 by Ray Butts for guitarist Chet Atkins who wasn’t satisfied by the DynaSonic pickup he was using. It has become a classic but often misunderstood pickup.

It has left a distinct mark on the sound of Rock’n’Roll. It’s the sound of Malcolm Young, Brian Setzer, Billy Duffy and plenty more. That unmistakable ‘Clank’ on the attack of the note is the essence of the FilterTron.

I started playing guitar because of the sound of A FilterTron. Listen to Malcolm Young on the intro to “Jailbreak” – that’s what I’m talking about.

But you don’t only find FilterTrons in Gretches, there’s the rather cool Fender Cabronita Telecaster.

So how does it make that distinctive sound? What makes it so different from a PAF?

Here’s a vintage Gretsch FilterTron from 1961, let’s take a look under the hood.

Gretsch FilterTron

With the cover off it looks quite different from a PAF. There are 2 rows of adjustable poles and they’re bigger than on a Gibson. The top of the bobbins are rather neatly hidden by a thin plate.

Filtertron with the cover off
Filtertron underneath
Gretsch FilterTron

Here’s where it gets really interesting. Those are very narrow bobbins and this one measures only 4.2KOhms. Not a lot of coil strength there but look what they’re sitting on. That is one fat magnet. It’s an Alnico V and literally twice the thickness of the Alnico 2 (usually) that you’d find in a PAF. So not only more powerful magnetic material but double the amount of it compared to a Gibson.

So that FilterTron sound consists of a weaker, thin sounding coil so lots of highs and twang from the windings and getting the aggression, attack and ‘clank’ from the powerful magnet.

This is the original FilterTron, the design didn’t change much through to the late 60’s although there are plenty of inconsistencies. They can have a dc resistance from 4KOhms up to 5KOhms.

By the 1970’s they had changed the design and really they just didn’t sound like Gretsch’s any more.


A lot of the modern ones are simply small humbuckers with cool looking covers and just miss the whole point of the FilterTron sound.

It’s all about those weak coils and that monster magnet.

Gretsch FilterTron
Mr Glyns Pickups

My own version of the FilterTron will be available soon.

Feel free to get in touch for pickup repairs or new pickups 021 912 678

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Yamaha SA30 pickup

Vintage Yamaha humbucker

This Yamaha SA30 pickup came to me for repair the other day and I decided to take some photos and share my thoughts on it with you.

Yamaha SA30 pickup - Mr Glyns Pickups

The Yamaha SA30 is becoming a bit of a legend and getting rather sought after. Gone are the days you could pick one up cheap – the word is out. Thank you internet 🥴.

If you don’t know about them here’s some info:

This pickup was sent to me with an intermittent fault. It would work if you tapped it but stop a minute later. That pointed towards it being an internal wiring fault rather than a broken coil, I needed to investigate.

Yamaha SA30 pickup - Mr Glyns Pickups
Yamaha SA30 pickup - Mr Glyns Pickups

With the cover off you can see the hook up wires – these were my number one suspects. Sure enough, there was a dry joint where one of them was soldered to the connectors on the base plate. Just to make sure I re- soldered all the joints and the pickup is fixed.

But that’s not the interesting part – look at those bobbins. They’re different sizes. They each measure in the 4.5 K Ohms range but they’re clearly wound with different gauge wire on each coil. These pickups are renowned for their clarity – so what’s going on?

The smaller coil on the left must be wound with thinner gauge wire and less of it than the one on the right. Thinner wire have a greater resistance for the same length.

The coil on the right looks like a conventional humbucker coil like an overwound PAF but the coil on the left would have a less full sound. It will have less bottom and lower mids and a lot less power. But that’s just the windings.

bobbins - Mr Glyns Pickups

Turn the pickup over and you can see a ceramic bar magnet but it’s how it connects to the poles that’s interesting. The bigger coil has a larger piece of steel coupling the poles to the magnet than the smaller coil. Measuring the strength of the magnetic field on the top of the poles the smaller coil is about 20% weaker. So this again gives the big coil an overwound PAF sound and the smaller coil still thinner.

 - Mr Glyns Pickups

So with the Yamaha SA30 pickup they’ve created that clarity by having one coil doing most of the work – 4.5k Ohms with a ceramic magnet has a bit more grunt than one half of a PAF. But the other coil on it’s own would have more of a weedy gold foil type sound. Then they’ve been combined in series as a humbucker. Smart stuff eh!

Feel free to contact me for pickup repairs or for a chat about my range of new pickups.

And here’s a great site for all things Yamaha SA, heaps of information here

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‘78 Musicman Stingray Bass pickup re-wind

Musicman Stingray bass pickup

The Musicman Stingray bass is for me one of the top 3 basses ever – the Precision, the Jazz and the Stingray cover pretty much everything between them. A big part of what makes the Stingray so good is the Musicman Stingray Bass pickup.

It has such a distinctive sound. Once you’re tuned into it you can hear it on so many recordings.

This pickup is from 1978 (they started in 1976) and was sent to me from a customer in Christchurch. I thought I’d show you around inside it – these are really interesting pickups.

Music Man Stingray bass pickup
‘78 Musicman Stingray Bass pickup

The Musicman Stingray Bass pickup is by the look of it a big fat humbucker but there’s more to it.

The magnets are big alnicoV’s, 3/8” diameter and 5/8” deep so a lot of the power and grunt comes from them. The 2 coils are wound with awg 42 wire and are around 4KOhms each (they vary). The poles on each coil have opposite polarity and the coils are wired out of phase electrically so they act as a humbucker. The really interesting part is the coils are wired in parallel, not in series like most humbuckers.

The sound of 2 coils in parallel is the sound of a Jazz bass with both pickups on or a Strat on switch position 2 or 4. It’s a very distinctive, clear tone with a very clear midrange and chimney bass.

So the distinctive Stingray sound comprises of fairly low powered coils in parallel to give plenty of clarity but with exceptionally fat magnets to give bass and grunty mids.

I haven’t mentioned the active circuit the signal goes through yet but that’s another story.

Music Man Stingray bass pickup, cover off
‘78 Musicman Stingray Bass pickup

As you can see, under the cover it looks very similar to ‘Fender’ pickups.

Music Man Stingray bass pickup
‘78 Musicman Stingray Bass pickup

One coil was open circuit so I cut the windings out. There was tape wrapped around the magnets to protect the coil. I left that in. I love the way they staggered the pole pieces but kept the magnets the same size.

Music Man Stingray bass pickup repair
pickup re-wind

The original winding wire is insulated with red poly. Unfortunately I only had Poly insulation in the natural colour – that’s my coil on the right.

Music Man Stingray bass pickup
MusicMan Stingray Pickup

And there she is, all ready to go back in to the bass.

If anyone has a faulty pickup just give me a call 021912678 or email

Take a look at my YouTube series “Mr Glyn Meets Your Maker” where I have chat with manufacturers of musical gear from around New Zealand