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Hoffman Amps Forum image Author Topic: filtertron build  (Read 8411 times)

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Offline Toxophilite

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filtertron build
« on: January 14, 2016, 12:10:30 am »
I just wound up a filtertron (grestch style low impedance humbucker)  using a kit from antique electronics supply and some magnet wire I bought off of ebay and it sounds pretty nice. I'm trying it in the bridge position of one of my arch tops to thicken it up a little.
pictures to follow

Offline Toxophilite

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Re: filtertron build
« Reply #1 on: January 14, 2016, 12:49:57 am »
Here it is next to a 60s hilotron

Offline EL34

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Re: filtertron build
« Reply #2 on: January 14, 2016, 11:23:25 am »
Cool, how did you count the windings and keep them wound nice and neat?

Offline Toxophilite

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Re: filtertron build
« Reply #3 on: January 14, 2016, 03:00:18 pm »
Thanks
I wish the winding count was my idea but I found it on the net


I'm not going into production so I made a temporary makeshift setup however one could easily use this same basic idea if one built a few permanent features. there's many examples on the internet, people use sewing machines too!


I'm using my cordless drill as a winder, the chuck has a short length of bamboo skewer taped to it which essentially makes it a cam
(as you can see I'm big in to masking tape for temporary things)


There's a pair of copper contacts(salvaged from an organ) set up above the chuck so that when the 'cam' comes around it hits and closes the contacts


the contacts are wired to the left click button on an old mouse


the calculator is open on my computer desktop 


I type in 1+ and then put the cursor on the equals button


If you have the contacts pretty close to each other and mounted close to the drills chuck then it can count accurately even at faster speeds
the bobbin is mounted on an old medicine bottle :icon_biggrin:
Things are lined up and a simple guide is fashioned from pliable wire to keep the wire from leaving the bobbin (^%$%6 annoying!)


A easy to use 'speed control was fashioned from two sticks(got this idea from the bowyers bible in the section on building your own spinning wheel from a hand drill)


Here's a picture of the whole makeshift deal. When in doubt or when something gets loose I just applied more tape :icon_biggrin:


Old Gretsch pickups are fairly loosely wound and I hand fed the wire onto the bobbin essentially making them 'scatterwound' . That seems to work just fine


However when I rewound my first hilotron pickup with 44 guage(THIN) wire I was able to get a very tight and even wind on it




Hilotrons have about 3000 windings and filtertrons have about 2000 per coil


for the photo I just loosely stuck a hilotron bobbin in the drills chuck as I'm actually about to dismantle the unit(makes it hard to drill anything!! :icon_biggrin: )



« Last Edit: January 14, 2016, 03:03:10 pm by Toxophilite »

Offline Ed_Chambley

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Re: filtertron build
« Reply #4 on: January 14, 2016, 04:03:05 pm »
Cool idea.  What is the nail polish remover for?

Did it turn out to have a nice gritty tone?

Offline Toxophilite

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Re: filtertron build
« Reply #5 on: January 14, 2016, 04:49:02 pm »
The nail polish remover is my drink of choice when winding pickups :icon_biggrin:



seriously though
I had used some two sided tape to mount the pickup rings/surrounds/bezels on my guitar. I was using the  nail polish remover to remove the residue when I swapped a new pickup in.


I find the idea of tone rather subjective, However I will tell you what I experienced from last night's rehearsal and you can come to your own conclusions
I still have to monkey with the individual pole pieces a bit to get the balance perfect between the two pickups
I was playing clean stuff(and I mean CLEAN!) and distorted stuff which I use pedals for (MXR dist+ and a boss super overdrive)
I need to use a large variety of sounds.


This filtertron is wound to 4.5k that's two approx 2.25 k coils in series
That's within the range of the older ones
(gretsch single coil hilotrons are typically 2.8 - 3.4K)


As expected the humbucking filtertron sounded 'thicker' than the single coil hilotron which I used to have in the bridge position, but still quite bright, maybe a little less extreme highs and lows , more mids,  but still very clear and even. Certainly brighter than a normal high output humbucker which I tend to find kind of muddy sounding though a lot of musicians I like use them.


This is all pretty well par for gretsch filtertrons. People claim the sound to be somewhere between a single coil and a regular humbucker.

I use the middle position alot! and for cleans I think I prefer the two single coils together
Though the humbucker still sounded great in this application (very clean and clear, yet thicker) I just like the single coils better., That's opinion.


However i thought it sounded really good through the distortion pedals, for lack of an adequate technical language I would say it was a little more growly and single notes were fatter. In this regard I would say it surpassed the single coil hilotron














« Last Edit: January 14, 2016, 04:51:24 pm by Toxophilite »

Offline sluckey

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Re: filtertron build
« Reply #6 on: January 14, 2016, 07:34:43 pm »
I would have thought the nail polish remover was used to strip the varnish coating from the magnet wire?
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline Willabe

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Re: filtertron build
« Reply #7 on: January 14, 2016, 08:06:28 pm »
Isn't nail polish remover acetone? That's strong stuff, I wouldn't use that on a guitar finish.  :help:

Offline Toxophilite

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Re: filtertron build
« Reply #8 on: January 14, 2016, 08:20:20 pm »
Hey with the right mixer the stuff ain't bad drinkin' :icon_biggrin:


I use 600 grit to strip the enamel from the wire ends, but using the nail polish remover is another good idea

Offline Toxophilite

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Re: filtertron build
« Reply #9 on: January 14, 2016, 08:29:56 pm »
yes acetone
When I worked at Larivee buffing the high end acoustics we used acetone regularly to clean up little problems,  with a quick wipe of course, we didn't pour the stuff on
This guitar has a bulletproof plastic finish which seems to not mind at all (I tested it in a non visible area first)
Also this particular bottle was left open for quite a while so it's as strong as normal


I wouldn't recommend others use it. For eg; the finish on my old Gretsch will respond poorly to water cleaning or standard martin guitar polish! I remember when I was taking a luthier course and an expert on french polishing came in . I had my gretsch in , fixing the headstock :icon_biggrin:  and he insisted on using it as a test guitar despite my protests. He was older and 'wiser' ,a teacher!, and I was very young, needless to say it all went wrong and he kind of mumbled some excuse about some finishes and passed my guitar back to me with a smudged mark on the finish. Hilarious!.....well now it is

Offline Willabe

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Re: filtertron build
« Reply #10 on: January 14, 2016, 08:49:16 pm »
When I worked at Larivee buffing the high end acoustics we used acetone regularly to clean up little problems,  with a quick wipe of course, we didn't pour the stuff on

Ok, I stand corrected. Larivee knows way more than I do about guitar finishes.   

Offline Toxophilite

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Re: filtertron build
« Reply #11 on: January 14, 2016, 09:00:25 pm »
I'm not recommending it however! Don't go acetone-ing your guitars!!..besides this is a pickup thread
Disregard all NON-pickup information!! :icon_biggrin:

Offline Willabe

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Re: filtertron build
« Reply #12 on: January 14, 2016, 09:14:24 pm »
I'm not recommending it however! Don't go acetone-ing your guitars!!..besides this is a pickup thread
Disregard all NON-pickup information!! :icon_biggrin:

Ok!  :laugh:

 


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